TY - CONF A1 - Seeger, Stefan T1 - Analysis of air pollutants in ambient and indoor aerosolsby TXRF - application examples N2 - Quantitative chemical analysis of airborne particulate matter (PM) is vital for the understanding of health effects in indoor and outdoor environments, as well as for enforcing air quality regulations. Typically, airborne particles are sampled over long time periods on filters, followed by lab-based analysis, e.g., with inductively coupled plasma mass spectrometry (ICP-MS). Within the EURAMET EMPIR AEROMET project, cascade impactor aerosol sampling was combined for the first time with on-site total reflection X-ray fluorescence (TXRF) spectroscopy to develop a tool for quantifying particle element compositions within short time intervals and even on-site. This makes variations of aerosol chemistry observable with time resolution of only a few hours and with good size resolution in the PM10 range. A proof of principles of this methodological approach and the comparison to standard methods within the scope of a field campaign will be presented. Secondly, aerosol sampling and TXRF analysis seems suitable for the quantification of elements in indoor aerosols as well and may provide an important enhancement of existing methods for the analysis of organic species in aerosols (such as sampling and TD-GC/MS). As an example, the TXRF analysis of particles emitted from laser printers under controlled conditions in an environmental test chamber will be presented. T2 - TXRF Journal ClubB CY - Online meeeting DA - 24.02.2022 KW - Aerosol KW - TXRF KW - Cascade impactor KW - ICP-MS KW - Particles KW - Air quality monitoring KW - Element mass concentration PY - 2022 AN - OPUS4-54418 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Cook, Jake Thomas T1 - Assessment of concrete bioreceptivity in algal biofilm green façade systems N2 - Algal biofilm façades are an alternative to traditional green façades which can help to improve biodiversity and air quality within cities. They present a low maintenance approach in which subaerial algae are grown directly on concrete substrates. The intrinsic bioreceptivity of the substrate is a critical factor in successful facade colonisation. Existing research has identified several environmental and material properties which influence concrete bioreceptivity, however a consensus has yet to be made on which properties are most influential and how the interaction between properties may promote algal biofilm growth under specific conditions. T2 - International Conference on Bio-Based Building Materials CY - Vienna, Austria DA - 21.06.2023 KW - Concrete KW - Façade KW - Bio-receptive KW - Extracellular polymeric substances KW - Fractional factorial PY - 2023 UR - https://www.rilem.net/agenda/5th-international-conference-on-bio-based-building-materials-1501 AN - OPUS4-58976 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fuentes, Elsa A1 - Prieto, Beatriz T1 - Effect of climate change on phototrophic biofilms colonizing granitic rocks and their biodeteriogenic activity. N2 - Material cultural heritage from NW of the Iberian Peninsula is linked to the use or presence of granite, whether in historical buildings, sculptures, archaeological sites or any other artistic manifestation. This resistant material has the ideal physical characteristics that favor its longevity, but, like any material exposed to the environment, it is susceptible to deterioration. To this respect, environmental changes due to climate change and global change may modify biological colonization-substrate interactions. The main objective of the present research was to analyse the effects of Climate Change, more specifically changes in water availability, increased temperature, increased CO2 concentrations and changes in UV-B radiation patterns, on the survival and biodeteriogenic activity of phototrophic biofilms on granite heritage and the consequences for the built heritage. Both field and laboratory work were carried out. Field studies were conducted on three rural churches to characterise the current biological colonization. A higher proportion of algae than cyanobacteria was identified, with the genera Trentepohlia and Desmococcus standing out among the former. The most common current fungi are lichenised fungi, but black fungal genera such as Catenulostroma, Rhinocladiella and Knufia were also identified. Bacterial genera related to the production of sphinganes, EPS, carotenoids and some causing the so-called pink discolouration are also present. The effect of climate change on the growth and physiological state of the organisms was analysed in the laboratory. For this purpose, mixed biofilms were developed in the laboratory and exposed to changing conditions of temperature, water availability, CO2 and UV-B. A reduction in growth was observed with increasing water restriction, although in the initial colonization process, rock bioreceptivity was shown to be a more important aspect in favoring anchorage and retention of organisms. Temperature was shown to have a growth-enhancing effect when water availability was low, whereas an increase in CO2 only resulted in increased growth under conditions of high-water availability. Increased UV-B produced a reduction in growth, especially at the highest dose (equivalent to the current dose of a west-facing wall in southern Portugal, which is considered as high), while little difference in the physiological state of the organisms was observed at the current doses in Galicia (considered as medium) and southern Ireland (considered as low). Clear changes in microbial composition were observed, with a trend towards increased or greater resistance of cyanobacteria to higher temperature, lower water availability and higher UV-B doses. In addition, all these changes in development, physiological and microbial composition had an effect on the predominant pigments, tending towards more yellowish-brownish colourations, and on the ability of the organisms to generate biodeterioration by affecting ion concentrations on water solutions by enhancing their consumption or adhesion which lead to granite deterioration. Future work should take into account the combination of a greater number of climatic parameters simultaneously and also the possible resistances associated with the nature of the SAB community studied. T2 - 19th International Biodeterioration and Biodegradation Symposium CY - Berlin, Germany DA - 09.09.2024 KW - Biofilm KW - Granite KW - Climate change KW - Biodeterioration KW - Cultural heritage PY - 2024 AN - OPUS4-62271 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Taghavi Kalajahi, Sara T1 - Pilot Study of a Laboratory- Based Microbiologically Influenced Corrosion (MIC) Test Using Microbiological Consortia Sampled from the Field N2 - Experts widely agree that the verification of microbiologically influenced corrosion (MIC) require the use of multiple lines of evidence (MLOE), including metallurgical, microbiological, operational/historical and environmental/chemical aspects. Existing standards related to MIC, such as NACE TM0106, TMO212 and TM0194, primarily aim to offer guidance on gathering such evidence. Working Group 5 of Euro-MIC COST action 20130 (Achieving standardization) proposed a laboratory-based approach that directly confirms the capability of the sampled consortium of microorganisms, obtained from the specific field location under investigation, to increase and/or alter the corrosion processes. It is necessary to verify this laboratory approach by conducting it in different laboratories, performed by different scientist. In the current study, the experiments based on the laboratory protocol of WG5 were conducted at Endures’s laboratory using environmental samples (sediment and seawater) from the North Sea. Metal coupons (carbon steel C1010) were exposed to sediment and seawater samples with varying microbial inoculums and controls over 150 days. Microbial identification, corrosion product analysis, and surface morphology assessments were conducted using molecular and microscopy techniques. The results indicate distinct microbial influences, particularly in treatments containing yeast, which fostered heightened anaerobic activity, notably by sulfate-reducing bacteria (SRB). Weight loss measurements and surface analysis revealed elevated corrosion rates and susceptibility to pitting corrosion in microbial inoculum treatments, with yeast presence exacerbating corrosion processes. Elemental analysis confirmed the presence of iron sulfide in corrosion byproducts, affirming SRB activity. The findings emphasize the importance of employing a MLOE approach and investigating pitting corrosion to better understand the impact of microorganisms on metal corrosion in the marine environments. This study contributes to advancing knowledge in the field and developing standardization: the lab-to-field transition for MIC testing. T2 - MIC-STANDS CY - Lisbon, Portugal DA - 24.07.2024 KW - Microbiologically influenced corrosion (MIC), Multiple lines of evidence (MLOE) KW - Marine Corrosion KW - Achieving standardization PY - 2024 AN - OPUS4-61979 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gorbushina, Anna T1 - Life on the rocks and other hard surfaces N2 - After their discovery on rock surfaces in cold and hot deserts, a polyphyletic group of ascomycetous black fungi was found to dominate a range of hostile environments – natural and man-made, from salterns to dishwashers, roofs and solar panels. Together with bacteria and algae they may establish subaerial biofilms and cause weathering of the surfaces they grow on. Their impressive survival abilities as well as their constitutive protective pigmentation and cluster-like microcolony organisation are similar in environmental isolates as well as in heat-tolerant opportunistic pathogens of animals and humans. We selected the rock-inhabiting fungus Knufia petricola (class Eurotiomycetes, order Chaetothyriales) that exhibits all the characteristics of microcolonial black fungi such as yeast-like cell growth, absence of reproductive structures and constitutive dihydroxynaphthalene (DHN) melanogenesis (Nai et al. 2013, Fungal Genet Biol). We developed protocols to efficiently generate and transform protoplasts resulting in stable homokaryotic transformants by targeting genes involved in pigment synthesis. The differences between the wild-type fungus and its melanin-deficient mutants were tested in geomicrobiological experiments and measured are now discussed in detail, with special accent on the possible effects of the mutation on EPS and other exuded substances. T2 - Departmental colloquium of the Tuscia University CY - Viterbo, Italy DA - 14.02.2020 KW - Ascomycetes KW - Fungal biofilms KW - Material surface colonisation KW - Genetics KW - Genomics KW - Extremophilic fungi PY - 2020 AN - OPUS4-50643 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Strzelczyk, Rebecca T1 - Constant emitting reference material for emissions test procedures N2 - Since nowadays people spend most of their time indoors, a healthy environment is essential. Volatile organic compounds (VOCs) emitted from furniture and building materials are reported to cause health complaints. Therefore, the usage of low emitting materials will improve the indoor air quality. Quantitative VOC emission testing is usually conducted in emission test chambers under specified controlled conditions as described in DIN 16000-9 and DIN EN 16516. For reasons of quality control/quality assurance (QC/QA) and for a better comparability of test results from different laboratories, suitable emission reference materials (ERM) are needed. Here, it is important to have a homogenous material with known emission rates over a specific time. Different approaches can be found in literature, inter alia polymer films loaded with the target compound to be released again, or a lacquer material to which a VOC mixture is added. After curing of the lacquer, the material can be loaded into a test chamber. Drawback of those approaches are their relatively fast decreasing emission profiles. For QC/QA purposes according to the test standards, VOC sources with constant emission profiles are desirable. The EU-funded research project MetrIAQ “Metrology for the determination of emissions of dangerous substances from building materials into indoor air” is working on a multi-component ERM with an envisaged instability of ≤ 10 % in the emission rate over at least 14 days. Within a doctoral thesis porous materials are impregnated with VOCs. Supercritical CO2 is used as solvent. Thus, the impregnated material does not contain any solvent that may show a measurable amount of emission in the emission test chamber. Furthermore, CO2 has the benefits to have a good availability and low costs. For the selection of porous materials several properties like the pore size, the surface, and the interaction with the components in the atmosphere need to be considered. The impregnation method is optimised while the different porous materials are tested. For the selection of porous materials the pores need to be large enough for the VOC molecules, further influence of the pore size is tested. T2 - Healthy Buildings CY - Aachen, Germany DA - 11.06.2023 KW - VOC KW - Emission KW - Quality assurance KW - Reference material PY - 2023 AN - OPUS4-59842 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bell, Jérémy A1 - Climent, Estela A1 - Gotor, Raúl A1 - Tobias, Charlie A1 - Martin-Sanchez, Pedro M. A1 - Rurack, Knut T1 - Dipstick coated with polystyrene-silica core-shell particles for the detection of microbiological fuel contamination N2 - Microbial contamination of fuels by fungi or bacteria poses risks such as corrosion and fuel system fouling, which can lead to critical problems in refineries and distribution systems and has a significant economic impact at every stage of the process. Many factors have been cited as being responsible for microbial growth, like the presence of water in the storage tanks. In fact, only 1 % water in a storage system is sufficient for the growth of microorganisms like bacteria or yeasts, as well as for the development of fungal biomass at the oil/water interface. This work presents a rapid test for the accurate determination of genomic DNA from aqueous fuel extracts. The detection is based on the use of polystyrene-mesoporous silica core-shell particles onto which modified fluorescent molecular beacons are covalently grafted. These beacons contain in the hairpin loop a target sequence highly conserved in all bacteria, corresponding to a fragment of the 16S ribosomal RNA subunit. The designed single-stranded molecular beacon contained fluorescein as an internal indicator and a quencher in its proximity when not hybridized. Upon hybridization in presence of the target sequence, the indicator and the quencher are spatially separated, resulting in fluorescence enhancement. To perform the assay the developed particles were deposited on different glass fibre strips to obtain a portable and sensitive rapid test. The assays showed that the presence of genomic DNA extracts from bacteria down to 50–70 μg L–1 induced a fluorescence response. The optical read-out was adapted for on-site monitoring by fitting a 3D-printed case to a conventional smartphone, taking advantages of the sensitivity of the CMOS detector. Such embedded assembly enabled the detection of genomic DNA in aqueous extracts down to the mg L–1 range and represents an interesting step toward on-site monitoring of fuel contamination. T2 - IMA 2023 CY - Chania, Greece DA - 18.09.2023 KW - Teststreifen KW - Test strip KW - Microbial KW - Mikrobiell KW - Smartphone KW - Particles KW - Partikeln PY - 2023 AN - OPUS4-58526 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schumacher, Julia A1 - Gorbushina, Anna T1 - Schwarze Pilze – Wüstenbesiedler finden neue Lebensräume N2 - Schwarze mikrokoloniale Pilze besiedeln zunehmend von Menschen geschaffene Habitate, wie schadstoffbelastete Böden, Statuen, Gebäudefassaden und Dächer. Sie verfärben und zersetzen die Oberflächen von anfälligen Materialien oder reduzieren die Lichtausbeute von Solaranlagen. Die Biologie dieser Pilze und ihre Relevanz für die Materialforschung stehen im Fokus unserer Studien an der Bundesanstalt für Materialforschung und -prüfung (BAM). Mit einer Kollektion schwarzer Pilze, die von Solaranlagen isoliert wurden, bringen wir klima- und materialrelevante Biodiversität in den Stammbaum des Lebens. Die Überlebensstrategien dieser Organismen versuchen wir mit molekularbiologischen und genetischen Untersuchungsansätzen zu entschlüsseln. KW - Pilze KW - Genetik KW - Diversität PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-541037 DO - https://doi.org/10.1007/s12268-021-1646-9 VL - 27 IS - 6 SP - 665 EP - 666 PB - Springer AN - OPUS4-54103 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schumacher, Julia T1 - CRISPR-Cas9 in der Materialforschung - Den gesteinsbesiedelnden Pilzen auf der Spur T1 - CRISPR-Cas9 in materials research - On the trail of rock-inhabiting fungi N2 - Das mikroskopische Leben auf exponierten Oberflächen ist genügsam und kooperativ. Gesteinsbesiedelnde schwarze Pilze, Grünalgen und Cyanobakterien unterstützen einander in der Eroberung von Felsen, Mauern, Denkmälern, Dächern, Fassaden und Sonnenkollektoren. Bedeutend sind die schwarzen Pilze als Gesteinszerstörer und Biofilmbildner. Ihre massiven Zellwände und ihr langsames Wachstum machen sie stresstolerant und fordern zugleich die experimentelle Forschung heraus. In der Materialforschung können Biofilme erwünscht oder unerwünscht sein. Biofilme auf Fassaden können das Innenstadtklima positiv beeinflussen, während sie auf einem Marmordenkmal unwillkommen sind. Ohne tieferes Verständnis der angepassten Mikroben ist weder ihre Bekämpfung noch ihre gezielte Förderung auf Materialien möglich. Hier treffen sich Genetik und Materialforschung: Die CRISPR-Cas9-Technologie ermöglicht es, die Genome der Pilze für funktionale Analysen zu editieren, um die Mechanismen der Materialbesiedlung und Materialschädigung zu entschlüsseln. N2 - Rock-inhabiting black fungi are adapted to the harsh life on rocks in deserts and release minerals from the rocks. The same adaptations enable these fungi to colonize man-made surfaces such as monuments, building facades and solar systems. Black fungi are often associated with phototrophic microorganisms. The slow growth and the melanized cell walls, which protect the fungi from extreme environmental infuences, render molecular biological and genetic engineering methods diffcult, which is why little is known about the biology of these fungi. Knufa petricola was selected to understand the processes of material colonization and damage with the help of adapted methods such as CRISPR-Cas9-mediated genome editing. KW - Knufia petricola KW - Schwarze Pilze KW - Bioflme KW - Genomeditierung KW - Pigmente KW - Multiplexing KW - Resistenzkassette KW - Transformanten KW - Knufia petricola KW - Black fungi KW - Biofilms KW - Pigments KW - Genome editing KW - Multiplexing KW - Resistance cassette KW - Transformants PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-620500 DO - https://doi.org/10.11576/biuz-7595 SN - 0045-205X SN - 1521-415X N1 - Volltext (PDF) in deutsch und englisch - Full text (PDF) in German and English VL - 54 SP - 41 EP - 50 PB - Verband Biologie, Biowissenschaften und Biomedizin in Deutschland (VBiO) CY - München AN - OPUS4-62050 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schumacher, Julia T1 - Schwarze Pilze: Robuste Multitalente für die Biotechnologie T1 - Black fungi: Robust all-rounders for biotechnology N2 - Knufia petricola ist ein gesteinsbesiedelnder Pilz aus der polyphyletischen Gruppe der schwarzen Pilze. Diese Pilze entwickelten außergewöhnliche – und bisher kaum erforschte – Fähigkeiten, in verschiedenen extremen Umgebungen zu gedeihen. Die Nutzung der genetischen Vielfalt des Genoms von schwarzen Pilzen und die Nutzung von K. petricola als alternativer Wirt für die Produktion von Enzymen und Sekundärmetaboliten eröffnen Perspektiven für die Nutzung dieser bislang wenig bekannten Pilze für biotechnologische Anwendungen. N2 - Knufia petricola is a rock-inhabiting fungus belonging to the polyphyletic group of black fungi. These fungi developed extraordinary – and so far hardly studied – capabilities to thrive in different extreme environments. Accessing the genetic diversity of black fungal genomes and using K. petricola as an alternative host for producing enzymes and secondary metabolites opens perspectives for utilizing these so far little recognized fungi for biotechnological applications. KW - Knufia petricola KW - Fungal pigments KW - Genetic engineering KW - Knufia petricola KW - Pilzpigmente KW - Gentechnik PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-628150 DO - https://doi.org/10.1007/s12268-025-2442-8 SN - 0947-0867 SN - 1868-6249 VL - 31 IS - 2 SP - 159 EP - 162 PB - Springer CY - Heidelberg AN - OPUS4-62815 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Abdallah, Khaled A1 - Stock, S. C. A1 - Heeger, Felix A1 - Koester, M. A1 - Nájera, F. A1 - Merino, C. A1 - Spielvogel, S. A1 - Gorbushina, Anna A1 - Kuzyakov, Y. A1 - Dippold, M. A. T1 - Nitrogen Gain and Loss Along an Ecosystem Sequence: From Semi-desert to Rainforest N2 - Plants and microorganisms, besides the climate, drive nitrogen (N) cycling in ecosystems. Our objective was to investigate N losses and N acquisition strategies along a unique ecosystem-sequence (ecosequence) ranging from arid shrubland through Mediterranean woodland to temperate rainforest. These ecosystems differ in mean annual precipitation, mean annual temperate, and vegetation cover, but developed on similar granitoid soil parent material, were addressed using a combination of molecular biology and soil biogeochemical tools. Soil N and carbon (C) contents, δ15N signatures, activities of N acquiring extracellular enzymes as well as the abundance of soil bacteria and fungi, and diazotrophs in bulk topsoil and rhizosphere were determined. Relative fungal abundance in the rhizosphere was higher under woodland and forest than under shrubland. This indicates toward plants' higher C investment into fungi in the Mediterranean and temperate rainforest sites than in the arid site. Fungi are likely to decompose lignified forest litter for efficient recycling of litter-derived N and further nutrients. Rhizosphere—a hotspot for the N fixation—was enriched in diazotrophs (factor 8 to 16 in comparison to bulk topsoil) emphasizing the general importance of root/microbe association in N cycle. These results show that the temperate rainforest is an N acquiring ecosystem, whereas N in the arid shrubland is strongly recycled. Simultaneously, the strongest 15N enrichment with decreasing N content with depth was detected in the Mediterranean woodland, indicating that N mineralization and loss is highest (and likely the fastest) in the woodland across the continental transect. Higher relative aminopeptidase activities in the woodland than in the forest enabled a fast N mineralization. Relative aminopeptidase activities were highest in the arid shrubland. The highest absolute chitinase activities were observed in the forest. This likely demonstrates that (a) plants and microorganisms in the arid shrubland invest largely into mobilization and reutilization of organically bound N by exoenzymes, and (b) that the ecosystem N nutrition shifts from a peptide-based N in the arid shrubland to a peptide- and chitin-based N nutrition in the temperate rainforest, where the high N demand is complemented by intensive N fixation in the rhizosphere. KW - Nitrogen KW - Rhizosphere KW - Microbial abundance KW - Natural abundance of 15N KW - Nitrogen fixation KW - Nitrogen uptake PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-543708 DO - https://doi.org/10.3389/fsoil.2022.817641 SN - 2673-8619 VL - 2 SP - 1 EP - 14 PB - Frontiers Media CY - Lausanne AN - OPUS4-54370 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Fuentes, Elsa A1 - Prieto, Beatriz A1 - Gorbushina, Anna T1 - Mixed model biofilm: interactions between algae, fungi and cyanobacteria and their effects on granite biodeterioration N2 - Granite, despite being one of the most widely used rocks for building material cultural heritage, is also one of the least studied. Previous works have shown that environmental parameters modulated by climate change will lead to changes in the microbial composition of biofilms grown on stone, but also to changes in the production of EPS, in the composition of pigments and, as a consequence, in the biodeterioration processes that this rock undergoes (Fuentes, 2023). Considering that the colonisation process is highly dynamic, small changes in climatic conditions can lead to the formation of different types of biofilms and diverse interactions between species. Knowing the contribution of the different organisms to the deterioration process is important both to anticipate the consequences that climate change will have on the deterioration of the granite, but also when addressing the processes of recolonization after cleaning, to ensure an improvement of the present situation. So, in order to continue my line of research on granite biodeterioration, the aim of this new project is to study the contribution of each type of organism (green algae, cyanobacteria and fungi) to the process of granite deterioration as well as the specific effect on each mineral, in addition to its role in the resilience and response of biofilms to environmental changes. With this main objective, the effect of the type of substrate on the composition of a model mixed biofilm formed by the fungus Knufia petricola, the algae Jaagichlorella sp. and the cyanobacterium Synechocystis sp. will be studied. The results obtained on granite will be compared with those obtained with other lithic types such as marble or limestone. Furthermore, it will be observed if the different ratios between organisms lead to changes in the capacity of these organisms to generate biodeterioration and to buffer climatic changes. Finally, the susceptibility of each mineral that makes up the granite - quartz, feldspars, micas - to biodeterioration mediated by each type of organism will be analysed. To address these questions, on the one hand, the response of the mixed biofilms as a whole will be evaluated by means of confocal microscopy, PAM, as well as the quantification of pigments and EPS, and on the other hand, the effect of these organisms on the deterioration of the substrates, through the use of SEM and TEM, which will allow the assessment of both the changes in porosity and the appearance of deterioration in the surface layers of the rock. This research will deepen the knowledge of the processes of granite deterioration, which have been limitedly studied in relation to microorganisms; but also aims to provide the scientific community with a model mixed biofilm to increase the reproducibility between experiments, one of the main limitations of this field of study. T2 - 19th International Biodeterioration and Biodegradation Symposium CY - Berlin, Germany DA - 09.09.2024 KW - Biofilm KW - Stone KW - Algae KW - Fungi KW - Cyanobacteria KW - Cultural heritage PY - 2024 AN - OPUS4-62272 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogel, Christian A1 - Urban, Klaus A1 - Ackerhans, C. A1 - Gorbushina, Anna T1 - Analysis of Carbon and Nitrogen from Atmospheric Sources by Bulk Deposition Sampling at various locations in Germany N2 - Atmospheric deposition of particulate matter is an important indicator of air pollution and a significant factor in material surface fouling. The elemental composition of this nutrient-containing dust depends largely on the exposure region and time as well as on climate. Therefore, in this paper we report an analysis of atmospheric pollutions with a self-made low-cost bulk deposition sampler directed at sampling deposition via air transport and rainfall. We used the device in diverse environments - thus comparing an urban region, an area surrounded by forest and an area mainly dominated by agriculture. The total organic carbon (TOC) and total nitrogen (TN) amounts were selected as indicator parameters and analyzed in a biweekly rhythm for three and a half and two years, respectively. The TOC value responded to particulate matter in the urban area, especially significant were the influences of the New Year's firework in urban and pollen in the rural forest area. In contrast, the TN value was more under the influence of the nitrogen emissions in the agriculture-dominated area. However, the TN value did not correlate with the NOx values in the urban area because the atmospheric nitrogen emissions in the city might originate from various emission sources. Summarizing, the TOC and TN values of the self-made low-cost bulk deposition sampler were in good agreement with environmental events of their immediate surrounding. Moreover, the selected containers and sampling procedures are universally applicable to monitor and analyze organic as well as inorganic parameters (e.g. metal ions) of atmospheric deposition. KW - Passive sampling KW - Biomonitoring KW - Air Analysis PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-609373 DO - https://doi.org/10.1016/j.envadv.2024.100583 SN - 2666-7657 VL - 17 SP - 1 EP - 9 PB - Elsevier Ltd. AN - OPUS4-60937 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gerrits, Ruben T1 - Genetic engineering of a black rock-inhabiting fungus shows its strengths and weaknesses  N2 - Environmental black fungi are known to inhabit anthropogenic habitats like marble monuments, solar panels, indoor walls and even washing machines. These pests are generally assumed to persist and grow in these environments due to their melanin production and oligotrophic lifestyle, respectively. We aimed to confirm these assumptions and to find methods to mitigate their substrate colonisation and deterioration by looking at their ability to produce melanin and take up iron, the latter being a general weakness of aerobes. This was done by means of selecting one species, Knufia petricola, and applying CRISPR/Cas9-mediated genome editing techniques. This showed that K. petricola produces one siderophore; deletion of its encoding gene showing no strong phenotypic effects. Deletion of the other iron uptake mechanism – reductive iron assimilation (RIA) – did however cause a strong growth deficiency at iron depleted conditions. Both together reveal that K. petricola has a weak siderophore and relies on RIA to acquire iron, reflecting a natural habitat free of competition for iron. This comes at a price: K. petricola but also other black fungi isolated from solar panels are extremely sensitive to mediocre iron chelators, offering us a mitigation strategy. Melanin, although adsorbing and reducing iron, did not have an observable effect on iron uptake. The pigment did however affect the fungal ability to withstand desiccation: pigment-deficient mutants were not able to withstand a prolonged incubation in a desiccator. This is a clear advantage in the colonisation of dry subaerial surfaces. T2 - 12th International Mycological Congress (IMC12) CY - Maastricht, Netherlands DA - 12.08.2024 KW - Iron uptake KW - Black fungi KW - Melanin PY - 2024 AN - OPUS4-62269 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schumacher, Julia T1 - The roles of DHN melanin and the stress-activated MAP kinase in the rock inhabitant Knufia petricola N2 - Black fungi/yeasts exhibit high stress tolerance, yeast‑like or meristematic growth, and constitutive 1,8-dihydroxynaphthalene (DHN) melanin formation. Due to their slow growth, robust cell walls and the lack of sexual cycles and genetic tools, the underlying mechanisms of their phenotypic traits have remained largely unexplored. Using recently developed genetic tools, it is now possible to manipulate the genome of the rock-inhabiting model fungus Knufia petricola. Thus, gene functions and the cell biology of black fungi can be studied using CRISPR/Cas9-based genome editing and live-cell imaging with genetically encoded fluorescent proteins. Here, we are addressing the question to which extent constitutive pigment formation (melanin and carotenoids) and responses mediated by the stress-activated mitogen-activated protein (MAP) kinase contribute to the observed extremotolerance of K. petricola. The mutations of pks1, phs1 and both genes result in melanin-free (pink), carotenoid-free (black) and pigment-free (white) strains, respectively. The other putative melanogenic genes were identified in the genome, deleted to confirm their involvement in DHN melanogenesis and co-expressed in Saccharomyces cerevisiae for reconstruction of the synthesis pathway. Sak1 encoding the stress-activated MAP kinase was deleted in the wild-type and different pigment-deficient backgrounds. Growth of the obtained single, double and triple deletion mutants was tested by droplet tests on media supplemented with different stress-inducing agents. The Δsak1 mutants show slightly reduced growth rates even without environmental pressure and are hypersensitive to different stresses: e.g. osmotic, oxidative, membrane, pH and heat stress. Melanin-free Δsak1 mutants are more sensitive than black Δsak1 mutants to some but not all stress conditions, suggesting that melanin and the SAK1 pathway have complementary roles in protecting K. petricola from stress. T2 - 16th European Conference on Fungal Genetics CY - Innsbruck, Austria DA - 05.03.2023 KW - Black fungus KW - Extremotolerance KW - Pigments PY - 2023 AN - OPUS4-57147 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Catanzaro, Ilaria T1 - Understanding the role of DHN melanin in Cryomyces antarcticus N2 - Cryomyces antarcticus – a cryptoendolithic black fungus endemic to Antarctica – is taxonomically classified in phylum Ascomycota, class Dothideomycetes incertae sedis. C. antarcticus has shown high capability to survive extreme environmental conditions like those found in space (ionizing radiation, vacuum, microgravity), thus fueling fundamental astrobiological questions like “searching for life beyond Earth” (Onofri et al. 2020, Extremophiles Astrobiol Model). Its extraordinary resilience has been attributed to the presence of thick, highly melanized cell walls, which may contain both DHN and DOPA melanins (Pacelli et al. 2020, Appl Microbiol Biotechnol). To better understand the contribution of DHN melanin to the overall resilience of C. antarcticus, we initially adopted chemicals e.g., tricyclazole to inhibit the DHN melanin synthetic pathway; however, these studies gave inconclusive results. Eventually, we decided to generate melanin-deficient mutants by genetic engineering. Using the genetic toolkit developed for the black fungus Knufia petricola (Voigt et al. 2020, Sci Rep; Erdmann et al. 2022, Front Fungal Biol), we designed a strategy for mutating the key enzyme (polyketide synthase)-encoding gene capks1 by transient delivery of Cas9 and capks1-specific sgRNA from AMA-containing plasmids and PCR-generated donor DNA i.e., resistance cassettes flanked by ~75-bp-long sequences homologous to capks1. For this, the melanin-PKS encoding ortholog was identified in the C. antarcticus CBS 116301 genome (mycocosm.jgi.doe.gov) and used to design primers for re-sequencing of the capks1 locus in the strain CCFEE 515. Transformation of C. antarcticus is challenging because of its very slow growth; we expect that 4-6 months are needed from obtaining enough biomass for cell wall lysis until transferring putatively resistant transformants for genotyping. Important parameters were evaluated: protoplasts can be generated, and they survive the transformation procedure, and suitable concentrations of selective agents have been identified. Nowadays, we are waiting for the first C. antarcticus mutants considered to be deficient in DHN melanogenesis. T2 - 16th European Conference on Fungal Genetics CY - Innsbruck, Austria DA - 05.03.2023 KW - Cryptoendolithic black fungus KW - DHN melanin KW - Astrobiology PY - 2023 AN - OPUS4-57145 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Werder, Julia T1 - Biofilme auf Gebäuden - Biorezeptivität statt Biofilme N2 - Der Vortrag erläutert das Konzept der Gebäudebegrünung mit Biofilmen. Beton wird dabei als künstliches Gestein betrachtet, dessen Besiedelbarkeit durch Mikroorganismen gezielt verbessert werden soll. Ein dreistufiges Testsystem – Laborversuche, simulierte Bewitterung und Freilandtests – analysiert, wie physikalische und chemische Substrateigenschaften das Wachstum beeinflussen. Ein definierter Algen‑Pilz‑Modellbiofilm dient zur reproduzierbaren Bewertung der Besiedlung, erfasst über PAM‑Fluorometrie. Die Ergebnisse zeigen, dass Rauheit, Textur und Porosität entscheidend für Anhaftung, Feuchteretention und Biofilmwachstum sind. Zudem wird deutlich, dass die Organismen hohe Stresstoleranz benötigen, um variierende Umweltbedingungen an realen Fassaden zu überstehen. Insgesamt belegt das Projekt das Potenzial biorezeptiver Betone als low‑tech‑Fassadenbegrünung mit ökologischem Mehrwert. T2 - Workshop Ökologische Campusentwicklung: Wasser und Vegetationsmanagement in Helmholtz-Zentren CY - Potsdam, Germany DA - 03.04.2025 KW - Biofilm KW - Fassade KW - Biorezeptivität KW - Low-tech Begrünung KW - Modellbiofilm PY - 2025 AN - OPUS4-65448 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stohl, Leonie A1 - Tonon, Chiara A1 - Cook, Jake A1 - Gorbushina, Anna A1 - Dehn, Frank A1 - von Werder, Julia A1 - Manninger, Tanja T1 - Understanding bioreceptivity of concrete: material design and characterization N2 - The climate crisis is driving an increasing demand for ecologically oriented concepts. In the building sector, this demand includes not only the use of environmentally friendly materials but also the greening of urban areas. One promising approach is the development of bioreceptive concrete façades, which support the growth of green biofilms directly on their surfaces. These innovative façades are anticipated to deliver benefits comparable to those of macroscopically greened façades, such as enhanced biodiversity and improved air quality, while offering the advantages of being more self-sustaining and stable systems once fully established. However, the development of bioreceptive concrete presents substantial challenges. Due to the interdisciplinarity and novelty of this field, standardized methods for material characterization and bioreceptivity assessment are currently lacking. This study proposes an approach for evaluating surface properties crucial for bioreceptivity, developed on differently structured samples of ultra-high-performance concrete (UHPC). Existing methods and standards from concrete technology are critically reviewed and, where necessary, modified to meet the unique requirements of measuring bioreceptive material properties. Special attention is given to the surface pH value and water retention characteristics, as these are essential for promoting microbial growth and ensuring the long-term stability of green biofilms. The observed surface characteristics vary according to the imprinted surface structures, offering a spectrum of material properties and enabling the evaluation of their impact on bioreceptivity. The findings presented form the foundation for subsequent laboratory weathering experiments, which will be discussed in a complementary publication. KW - Novel methods KW - Bioreceptivity testing PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-655023 DO - https://doi.org/10.1617/s11527-025-02863-y SN - 1359-5997 VL - 58 SP - 1 EP - 18 PB - Springer Science and Business Media LLC AN - OPUS4-65502 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gorbushina, Anna T1 - From rocks to riches: Knufia petricola as model and expression platform N2 - Black fungi belong to different classes of Ascomycota but evolved similar morpho-physiological adaptations such as yeast-like growth and constitutive melanin formation to colonize extreme competition-free environments. They are ubiquitously found on air-exposed surfaces, from ancient marble monuments to modern solar panels. The rock inhabitant Knufia petricola was chosen to become a model for these extremotolerant black fungi. Plasmid-based and ribonucleoprotein-based CRISPR/Cas9 techniques were introduced to precisely introduce one to multiple double strand breaks into the DNA to modify, replace or add sequences to the genome either using the available selection marker systems (hygR, natR, genR, baR, suR) or by marker-free approaches. Multiplexing is very efficient, allowing for four or more simultaneous genome editing events. The newly generated cloning vectors containing the Tet on construct for doxycycline-controlled gene expression, and the validated sites in the K. petricola genome for color-selectable (pks1, phs1, ade2) or neutral insertion (igr1 to 5) of expression constructs complete the reverse genetics toolbox. One or multiple endogenous or heterologous genes can be expressed on demand from different genomic loci or from a single construct by using 2A self-cleaving peptides. We thus can express genes from synthetic clusters in a non-pigmented background (Δpks1/Δphs1). The fact that K. petricola only produces few secondary metabolites (DHN melanin, carotenoids, mycosporines and a siderophore) and plant cell-wall degrading enzymes but is capable to take the burden of acetyl-CoA-consuming metabolism and protein secretion renders K. petricola a promising host for the expression of heterologous genes encoding high-end secondary metabolites and enzymes. T2 - 12th International Mycological Congress (IMC12) CY - Maastricht, Netherlands DA - 11.08.2024 KW - Fungus KW - Genetic engineering KW - Heterologous gene expression KW - Cell factory PY - 2024 AN - OPUS4-60838 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Breitenbach, Romy A1 - Gerrits, Ruben A1 - Dementyeva, Polina A1 - Knabe, Nicole A1 - Schumacher, Julia A1 - Feldmann, Ines A1 - Radnik, Jörg A1 - Ryo, M. A1 - Gorbushina, Anna T1 - Data for "The role of extracellular polymeric substances of fungal biofilms in mineral attachment and weathering" N2 - Data for the publication "The role of extracellular polymeric substances of fungal biofilms in mineral attachment and weathering" (https://doi.org/10.1038/s41529-022-00253-1). It includes: - The Summary of the EPS concentration, EPS sugar components and EPS linkages. - The Summary of the XPS analysis of freeze-dried biofilm samples of all strains. - The Summary of the pH, Mg, SI and Fe concentration, biomass and olivine dissolution rate for each time point of all dissolution experiments. KW - Biofilms PY - 2022 DO - https://doi.org/10.26272/opus4-54901 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-54901 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Catanzaro, Ilaria T1 - Generation of Cryomyces antarcticus mutants to explore the importance of DHN melanin for survival N2 - Cryomyces antarcticus, a cryptoendolithic melanized fungus endemic to Antarctica (phylum Ascomycota, class Dothideomycetes incertae sedis), has demonstrated high capability to survive extreme environmental conditions like those found in space (e.g., ionizing radiation, vacuum, microgravity), thus fueling fundamental astrobiological questions like “the search for life beyond Earth”. Its extraordinary resilience has been attributed to the presence of thick, highly melanized cell walls, which may contain both DHN and DOPA melanins. To better understand the contribution of DHN melanin to the overall resilience of C. antarcticus, we decided to generate melanin-deficient mutants by genetic engineering. For this, the melanin-PKS (polyketide synthase)- encoding ortholog was identified in the C. antarcticus CBS 116301 genome and used to design primers for re-sequencing of the capks1 locus in the strain CCFEE 515. Based on the genetic toolkit developed for the black fungus Knufia petricola, we designed a strategy for mutating capks1. Protoplasts of C. antarcticus CCFEE 515 were generated and co-transformed with a circular AMA-containing plasmid for expression and in-vivo assembly of Cas9 and two capks1-specific sgRNAs and a PCR-generated donor DNA i.e., a hygromycin resistance cassette flanked by ~75-bp-long sequences homologous to the capks1 locus. Transformation of C. antarcticus is challenging because of its very slow growth and uncertain gene copy number. It took six months from obtaining enough biomass for cell wall lysis to transferring the putatively resistant transformants for genotyping, but we eventually managed to generate three independent non-melanized (whitish) Δcapks1 mutants! We are now awaiting first complemented strains as ultimate genetic transformation control. They are considered to have a wild-type-like pigmentation due to the reintroduction of the wild-type capks1 into the Δcapks1 mutant. T2 - IUBMB Focused Meeting on Extremophilic Fungi (FUN-EX) CY - Ljubljana, Slovenia DA - 19.09.2023 KW - Black fungus KW - Genetics KW - UV tolerance KW - Melanin PY - 2023 AN - OPUS4-58458 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Schumacher, Julia ED - Scott, B. ED - Mesarich, C. T1 - Role of light in the life cycle of Botrytis cinerea N2 - The fungus Botrytis cinerea (Botryotinia fuckeliana) infects more than 500 plant species and causes a wide range of symptoms: soft rots, accompanied by collapse and water-soaking of tissues followed by the appearance of gray masses of conidia on leaves and soft fruits (gray mold), and spots that may turn brown to full-scale soft rotting on flower petals (Botrytis blight). In general, B. cinerea is responsible for severe economic losses that are either due to the damage of growing plants in the field or the rot of harvested fruits, flowers, and vegetables during storage under cold and humid conditions. B. cinerea has adapted to the plant host and its environment by evolving strategies to use plant tissues for proliferation in terms of a necrotrophic lifestyle, and to survive biotic stresses (host responses) as well as abiotic factors of the host’s environment such as sunlight and concomitant stresses. B. cinerea maintains a complex regulatory network of light-sensitive proteins and signal transduction pathways to use light for coordinating stress responses, virulence, and reproduction. Different light-controlled reproduction cycles enable B. cinerea to live in moderate climate zones by infecting and propagating in summer and resting in winter when green host tissues are unavailable. KW - Gray mold fungus KW - Plant pathogen KW - Light KW - Photoreceptors KW - Development PY - 2023 DO - https://doi.org/10.1007/978-3-031-16503-0_14 VL - 5 SP - 329 EP - 346 PB - Springer, Cham AN - OPUS4-56724 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gorbushina, Anna T1 - A genetic toolbox for exploring the life style of the rock-inhabiting black fungus Knufia petricola N2 - After their discovery on rock surfaces in cold and hot deserts, a polyphyletic group of ascomycetous black fungi was found to dominate a range of hostile environments – natural and man-made, from salterns to dishwashers, roofs and solar panels. Together with bacteria and algae they may establish subaerial biofilms and cause weathering of the surfaces they grow on. Their impressive survival abilities as well as their constitutive protective pigmentation and cluster-like microcolony organisation are similar in environmental isolates as well as in heat-tolerant opportunistic pathogens of animals and humans. The exact genetic properties that ensure their survival in extreme environments can be studied if some black fungi were amenable to genetic manipulations. We selected the rock-inhabiting fungus Knufia petricola (class Eurotiomycetes, order Chaetothyriales) that grows moderately in axenic culture and exhibits all the characteristics of microcolonial black fungi such as yeast-like cell growth, absence of reproductive structures and constitutive dihydroxynaphthalene (DHN) melanogenesis (Nai et al. 2013, Fungal Genet Biol). We developed protocols to efficiently generate and transform protoplasts resulting in stable homokaryotic transformants by targeting genes involved in pigment synthesis and expressing fluorescent reporter genes. Hence, endogenous and foreign genes can be expressed from episomal AMA1-containing plasmids and genome-integrated DNA constructs. Moderate rates of homologous recombination allow for both ectopic and targeted integrations. CRISPR-Cas9 was further validated as a strategy for obtaining selection marker-free mutants and silencing via RNA interference as an approach to study essential genes. Availability of this genetic toolbox and an annotated genome sequence of the strain A95 is paving the way for studying interactions of K. petricola with environmental stressors, material surfaces, soil matrices and phototrophic symbionts. T2 - European Conference on Fungal Genetics (ECFG15) CY - Rome, Italy DA - 17.02.2020 KW - black fungi KW - genomics KW - genetics PY - 2020 AN - OPUS4-50593 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schumacher, Julia T1 - Knufia petricola – a model for exploring the biology of black rock-inhabiting fungi N2 - Black fungi also called black yeasts, rock-inhabiting fungi or microcolonial fungi are a group of Ascomycetes [Eurotiomycetes, Arthoniomycetes and Dothideomycetes] that exhibit high stress tolerance, yeast‑like or meristematic growth, and constitutive 1,8-dihydroxynaphthalene (DHN) melanin formation. They dominate a range of hostile natural and man‑made environments – from desert rocks and salterns to dishwashers, roofs, and solar panels. Due to their slow growth and the lack of sexual cycles and genetic tools, the underlying mechanisms of black fungi’s phenotypic traits have remained largely unexplored. We consider the rock inhabitant K. petricola [Eurotiomycetes, Chaetothyriales] a suitable model for studying the phenotypic characteristics of black fungi. With K. petricola the regulation of pigment synthesis, general stress responses and the unusual modes of cell division can be dissected by advanced reverse and forward genetics approaches. The genome of K. petricola strain A95 was sequenced using a combination of short high quality Illumina reads and long PacBio reads. The final assembly consists of twelve contigs: five complete chromosomes and six contigs with one telomer each. Gene annotation supported by transcriptomics and proteomics data was manually curated. Recently, we developed a set of genetic tools to manipulate the genome for analyzing gene functions and studying the cell biology. This set includes CRISPR/Cas9-based genome editing and live-cell imaging using genetically encoded fluorescent proteins, as well as protocols for -omics approaches and for simulation of mineral weathering in the laboratory. Mutants defective in DHN melanogenesis, carotenogenesis or both processes are currently studied to elucidate the role of these protective pigments in tolerance of natural and man-made stresses, weathering of olivine, penetration of marble, and adhesion to surfaces. Further, the established protocols and knowledge gained from K. petricola form a starting point for making other extremotolerant black fungi accessible to genetic manipulation. T2 - 31st Fungal Genetics Conference CY - USA, CA, Pacific Grove DA - 15.03.2022 KW - Black fungi KW - Melanin KW - Genome editing PY - 2022 AN - OPUS4-54585 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dehkohneh, Abolfazl T1 - Effect of Carbon and Nitrogen on Growth of the Oligotrophic and Extremotolerant Fungus Knufia petricola N2 - Introduction: Rock-inhabiting black fungi are renowned for their constitutive melanin production, extremotolerance and ubiquitous colonization of oligotrophic, natural or anthropogenic subaerial surfaces, including marble monuments and solar panels. Knufia petricola is a model for these fungi as it is genetically amenable and has their typical characteristics. It is capable of colonizing and deteriorating minerals and produces extracellular polymeric substances that facilitate attachment. Objectives: The objective of this study is to understand how such an organism is able to grow in environments depleted of C and/or N. Method: K. petricola growth parameters (colony extension and thickness, biomass, CO2 respiration and carbon-use efficiency (CUE)) were analysed for different C to N ratios (C:N), changing both the C and N concentrations and sources. The study utilized a dual-scale approach, examining biofilm formation on agar (macroscale) and growth of a single cell into a microcolony in a microfluidic device (microscale). This methodology provided insights into the nutritional requirements and growth behaviours of K. petricola across different spatial scales. Findings: Our macroscale analysis indicated optimal growth at the C:N ratio of 60. The morphological analysis demonstrated that when nitrate is utilized as the N source, colonies tend to exhibit filamentous growth at their edges, especially when glucose is available as C source. In contrast, when ammonium is the N source, the colony surface appears smooth (Fig. 1A). Moreover, C or N depletion led to higher substrate penetration, mostly through filaments at the edge of the biofilm. Notably, the lowest carbon concentration yielded reduced biomass C:N ratio and the peak biomass C:N ratio was observed at the medium C:N ratio of 60, suggesting a potential correlation between C:N ratio and optimal growth (Fig. 1B). The CUE was however quite low, ca. 0.4-0.6, being lowest when C and N were limiting. Concurrently, microscale analyses of single cells revealed that increasing the C:N ratio from 0.6 to 60 caused (1) shorter cell cycles and (2) more branching, no branching formed without C and N (Fig. 1C). This led to a denser colony at optimal conditions and a rather extended morphology under C or N limitations. Conclusion: The findings demonstrate that the depletion of either carbon or nitrogen results in enhanced substrate penetration, predominantly through edge filaments. Notably, the optimal growth and peak biomass C:N ratio of 60 suggest both a correlation with and importance of the medium C:N ratio. Specifically, the lowest carbon input led to a reduced biomass C:N ratio, while the peak biomass C:N ratio was achieved at the medium C:N ratio of 60. T2 - FEMS MICRO conference CY - Milano, Italy DA - 14.07.2025 KW - Black fungi KW - Carbon-use efficiency KW - Polyextremotolerant KW - Oligotrophs KW - Rock-inhabiting fungi PY - 2025 AN - OPUS4-65038 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schumacher, Julia T1 - Many-sided DHN melanin – spotlight on its function in microcolonial black fungi N2 - Dihydroxynaphthalene (DHN) melanin is produced by different Ascomycetes via slightly differing biosynthetic routes. The polyketide synthases (PKS) release the heptaketide YWA1, the hexaketide AT4HN or the pentaketide T4HN. The first two products are deacetylated by ‘yellowish-green’ hydrolases to T4HN, and T4HN is further converted by a core set of enzymes to DHN. Final polymerization steps are accomplished by multicopper oxidases. DHN melanogenesis is often regulated in a spatial and temporal fashion resulting e.g. in melanized reproduction, survival and/or infection structures. Remarkable is the regulation of the DHN melanogenesis in the foliar plant pathogen Botrytis cinerea: it involves two differently expressed PKSs providing the precursor in conidia and sclerotia, respectively (Schumacher 2016, Mol Microbiol). In contrast, a polyphyletic group of Ascomycetes (microcolonial fungi/ black yeast) dwelling in hostile habitats such as bare rock surfaces in hot and cold deserts, exhibits constitutive melanogenesis. Here, DHN melanin builds a protective layer around all vegetative cells thus contributing to the survival of diverse environmental stresses even without specialized reproduction structures. As part of our continuing research on microcolonial rock-inhabiting fungi, we chose the genetically amenable Knufia petricola strain A95 (Nai et al. 2013, Fungal Genet Biol; Noack-Schönmann et al. 2014, AMB Express) for detailed studies. DHN-deficient mutants generated by targeted mutation of biosynthetic genes were studied with regard to the architecture of the cell wall and the EPS (extracellular polymeric substances) matrix, attachment to and weathering of olivine, as well as the tolerance to abiotic and biotic stresses. We will discuss the critical role of the outer cell surface (DHN melanin and EPS) in adhesion to the substrate and subsequent damage of the colonized surface. T2 - European Conference on Fungal Genetics (ECFG15) CY - Rome, Italy DA - 17.02.2020 KW - fungus KW - melanin KW - pigmentation PY - 2020 AN - OPUS4-50591 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gerrits, Ruben T1 - Fungal biofilms are supported by EPS and protective pigments in their substrate attachment and desiccation tolerance N2 - Rock-inhabiting fungi are known to colonise air-exposed substrates like minerals, photovoltaic panels building facades and monuments, withstanding the various stresses these extreme habitats are known for. Here we show how both colonisation and stress resistance are linked to the properties of the fungal cell surface. By deleting genes involved in the synthesis of melanin and carotenoid pigments of the model rock-inhabiting fungus Knufia petricola via CRISPR-Cas and comparing the behaviour of the gene-deletion mutants with the wild type (WT), we studied the role of these genes in mineral colonisation and stress sensitivity. The extracellular polymeric substances (EPS) of biofilms of the WT and mutants were extracted, quantified and chemically characterised. We observed that the absence of melanin affected the quantity and composition of the produced EPS: melanin-deficient mutants synthesised more EPS containing fewer pullulan-related glycosidic linkages. Moreover, in mineral dissolution experiments, these mutants showed a lower ability to colonise the mineral olivine. We hypothesise that not melanin, but the pullulan-related linkages enabled the melanin-producing strains to attach more strongly to the mineral. Moreover, ICP-OES analysis of the aqueous mineral-derived solutes showed that biofilms of the K. petricola mutants which could attach were able to dissolve the olivine faster than those that could not. The same mutants were also characterised by their sensitivity to desiccation stress: only the mutant deficient in both melanin and carotenoid synthesis was more sensitive to desiccation compared to the WT, indicating that a combination of both pigments is critical to withstand desiccation. Overall, these results show the critical role of the cell surface in the specific capacities of rock-inhabiting fungi. T2 - Biofilms 10 CY - Leipzig, Germany DA - 09.05.2022 KW - Bio-weathering KW - Desiccation KW - Fungal biofilms PY - 2022 AN - OPUS4-56675 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erdmann, Eileen T1 - A random mutagenesis approach to elucidate the biology of extremotolerant black fungi N2 - Microcolonial black fungi ubiquitously inhabit sun-exposed natural and man-made surfaces of our planet. To promote genetic studies, which are hindered by slow growth, lack of sexual cycles and transformation difficulties, CRISPR/Cas9-based genetic tools were implemented (Erdmann et al. 2022, Front Fungal Biol). Now efficient targeted mutagenesis of the rock inhabitant Knufia petricola (Eurotiomycetes/Chaetothyriales) - as a representative of the polyphyletic group of black fungi - enables the elucidation of extremotolerance, oligotrophism, unusual types of cell division, mineral weathering and symbiotic interactions. Still more progress on assigning functions to yet unknown genes can be expected if a forward genetics approach is available. We chose the two-component Activator/ Dissociation (Ac/Ds) transposon system from maize for generating a collection of insertional mutants by in-vivo mutagenesis of K. petricola. For the optimal use of this genetic tool, an inducible promoter for the expression of the Ac transposase (AcTPase) and by this the regulatable transposition of the resistance cassette-containing Ds transposon is desired. However, endogenous promoters for nitrate assimilation and galactose catabolism - often used in fungi for regulatable gene expression - are not inducible by their substrates in K. petricola suggesting that the regulatory networks for nutrient acquisition differ significantly in oligotrophic fungi. Therefore, the metabolism-independent Tet-on system was combined with the AcTPase coding sequence and subsequently transformed into Ds-carrying K. petricola strains. In total, four auxotrophic Ac|Ds starter strains containing the Ds transposon at different position of ade2 or ura3 were generated. The cultivation of these strains with doxycycline for induction of TET::Ac and subsequent selection of cells on ADE/URA-lacking media resulted in prototrophic colonies (revertants) for some but not all Ac|Ds strains. Currently, the transposition events in the obtained revertants are studied to validate the procedure. First amplicon sequencing of excision sites revealed footprint patterns, proving the transposon jumped. T2 - 16th European Conference on Fungal Genetics CY - Innsbruck, Austria DA - 05.03.2023 KW - Rock-inhabiting fungi KW - Foward genetics KW - In-vivo mutagenesis PY - 2023 AN - OPUS4-57144 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dehkohneh, Abolfazl T1 - Modelling biofilm formation and material colonisation for Knufia petricola N2 - Rock-inhabiting black fungi are adapted to survive extreme stresses such as radiation and lack of water and are thus able to colonise arid material surfaces like solar panels and marble monuments. Black fungi can typically grow as one of two cell types: depending on the environmental conditions, they are able to form yeast-like cells or hyphal filaments. Knufia petricola is one member of the rock-inhabiting black fungi which functions as a model reference species. As there is no mathematical model for biofilm formation of RIF, we are going to develop a model for K. petricola which describes fungal growth on the level of individual cells adn biofilm formation. T2 - Mini conference at University of Birmingham CY - Birmingham, UK DA - 05.10.2022 KW - Knufia petricola KW - Rock-inhabiting black fungi KW - individual-based modelling PY - 2022 AN - OPUS4-56697 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schumacher, Julia T1 - Versatile DHN melanin – spotlight on its function in microcolonial black fungi N2 - Dihydroxynaphthalene (DHN) melanin is produced by diverse Ascomycetes via slightly differing biosynthetic routes. The polyketide synthases (PKS) release the heptaketide YWA1, the hexaketide AT4HN or the pentaketide T4HN. The first two products are deacetylated by ‘yellowish-green’ hydrolases to T4HN, and T4HN is further converted by a core set of enzymes to DHN. Final polymerization steps are accomplished by multicopper oxidases. DHN melanogenesis is often regulated in a spatial and temporal fashion resulting e.g., in melanized reproduction and survival structures of the foliar plant pathogen Botrytis cinerea (Schumacher 2016, Mol Microbiol). In contrast, a polyphyletic group of Ascomycetes (microcolonial fungi/ black yeasts) dwelling in hostile habitats such as bare rock surfaces in hot and cold deserts, exhibits constitutive melanogenesis. Here, DHN melanin builds a protective layer around all vegetative cells thus contributing to the survival of diverse environmental stresses even without specialized reproduction structures. For studying the relevance of constitutive DHN melanogenesis for tolerance of abiotic and biotic stresses, adhesion to substrates and subsequent damage of colonized surfaces, the rock-inhabiting fungus Knufia petricola was chosen as gene functions in this fungus can be studied by CRISPR/Cas9-based genome editing. The putative melanogenic genes were identified in the genome of K. petricola, deleted to confirm their involvement in DHN melanogenesis and co-expressed in Saccharomyces cerevisiae for reconstruction of the synthesis pathway. Phenotypes of DHN-deficient mutants are studied. Here, we will discuss the role of the DHN melanin layer on the outer cell wall in tolerating UV irradiation. T2 - Annual conference 2023 of the Association for General and Applied Microbiology CY - Göttingen, Germany DA - 10.09.2023 KW - Pigment KW - UV radiation KW - Tolerance PY - 2023 AN - OPUS4-58425 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erdmann, Eileen T1 - In-vivo mutagenesis of the rock inhabitant Knufia petricola by a customized Ac/Ds transposon system N2 - Microcolonial black fungi ubiquitously inhabit sun-exposed natural and man-made surfaces of our planet. To promote genetic studies, CRISPR/Cas9-based genome editing was implemented in the rock-inhabiting fungus Knufia petricola (Eurotiomycetes/ Chaetothyriales). Now efficient targeted mutagenesis of K. petricola - as a representative of the polyphyletic group of black fungi - enables the elucidation of extremotolerance, oligotrophism, unusual types of cell division, mineral weathering and symbiotic interactions. Even more progress on assigning functions to yet unknown genes can be achieved by a forward genetics approach. We chose the two-component Activator/Dissociation (Ac/Ds) transposon system from maize for generating K. petricola insertional mutants by in-vivo mutagenesis. For the optimal use of this genetic tool, an inducible promoter i.e, from the metabolism-independent Tet-on system, was combined with the AcTPase-coding sequence enabling the regulatable transposition of the resistance cassette-containing Ds transposon. In total, six auxotrophic Ac/Ds starter strains containing the Ds transposon at different position of ade2, ura3 or ppt1 were generated. The cultivation of these strains with doxycycline for induction of TET::Ac and subsequent selection of cells on ADE/URA/LYS-lacking media resulted in prototrophic colonies (revertants) for most Ac/Ds strains. Amplicon sequencing of excision sites revealed characteristic footprint patterns, proving that the transposon jumped. For identifying unknown Ds re-insertions sites, the thermal asymmetric interlaced (TAIL)-PCR was successfully implemented. First identified Ds re-insertion sites suggest that the distribution pattern may depend on the excision site. Currently, transposition frequencies and genome-wide distribution of re-insertion sites are studied in different Ac/Ds starter strains to identify the best candidate for generating saturated mutant libraries. This transposon mutagenesis strategy is also interesting for studying other black fungi, because once the Ac and Ds components are integrated in the genome, the fungus ‘only’ needs to be cultivated for generating insertional mutants. T2 - IUBMB Focused Meeting on Extremophilic Fungi (FUN-EX) CY - Ljubljana, Slovenia DA - 19.09.2023 KW - Black fungi KW - Genetics KW - Transposon KW - Mutagenesis PY - 2023 AN - OPUS4-58427 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dehkohneh, Abolfazl T1 - Fungal biofilms on materials: describing and modelling growth of the black fungus Knufia petricola N2 - Fungi that grow as biofilms are associated with clinical settings as well as various cases of material fouling and material damage. Black fungi as biofilm formers have been rarely studied so far. Their conspicuous dark pigmentation, EPS production, adhesion capabilities and adaptations to stresses allow black fungi to develop biofilms on materials under harsh conditions. For example, rock-inhabiting black fungi withstand sun irradiation and dehydration and are therefore ubiquitous on arid surfaces like solar panels and marble monuments. To understand and control their ability to colonise and deteriorate materials, one should assess and model black fungi’s growth patterns. But so far, no mathematical model has been developed to describe their growth. Knufia petricola A95, representing rock-inhabiting fungi from Chaetothyriales, is genetically amenable and can serve as a model for biofilm studies in black fungi. The primary objective of this project is to develop a growth model for K. petricola A95 which will enable to define and predict material colonisation of black fungi. Dedicated experimental work with K. petricola will allow the quantitative assessment of the impact of environmental conditions (e.g. pH, nutrients, etc.) on the growth behaviour at the biofilm and single cells level. Data which will be used to validate and develop an individual-based model (based on the iDynoMICS modelling platform) that explains how fungal biofilms form, colonise materials, and cause deterioration. Thus far, research has been conducted on the impact of different concentrations and sources of major elements (e.g. C, N, …), as well as trace elements (e.g. Cu, Mg, …), on the colony shape and biomass of Knufia petricola A95 biofilms. To study the behaviour of single cells, the length of the cell cycle in different growth media has been determined via the combined use of microfluidic devices and confocal microscopy. T2 - IUBMB Focused Meeting on Extremophilic Fungi (FUN-EX) CY - Ljubljana, Slovenia DA - 19.09.2023 KW - Biofilm KW - Rock-inhabiting fungus KW - Mathematical modelling PY - 2023 AN - OPUS4-58438 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gerrits, Ruben T1 - The role of melanin in fungal mineral weathering and metal corrosion N2 - Melanins are organic pigments produced by most fungi. These organisms either fix these pigments in their cell wall or secrete them into their extracellular environment to protect themselves against an array of physicochemical stresses (e.g., UV irradiation, desiccation, ...). Melanin can adsorb metals like Fe. How this affects fungal uptake of Fe and deterioration of Fe-containing minerals and metals is however less known. To study this, we use the model fungi Knufia petricola A95, a rock-inhabiting fungus known to deteriorate minerals and have melanised cell walls, and Amorphotheca resinae, able to contaminate fuel tanks, secrete melanin and corrode metals. In K. petricola, we have deleted genes involved in melanin production and Fe uptake using CRISPR/Cas. Through comparison of the geochemical signatures of these gene deletion mutants with those of the wild type (WT), we explore the specific mineral/metal deterioration mechanisms of melanised fungi. Fe isotope signatures of the biomass of melanin- and Fe uptake-deficient mutants of K. petricola revealed that Fe adsorbed either directly onto melanin or after being reduced by Fe reductases. Importantly, once adsorbed to melanin, Fe could not be mobilised and taken up into the cell: both the WT and its melanin-deficient mutant, previously grown at Fe replete conditions, showed similar growth at Fe deficient conditions. Olivine dissolution experiments revealed that Fe oxidation inhibits dissolution. K. petricola was able to enhance dissolution when this inhibition is strongest (at pH 6) and prevented dissolution when this inhibition is weakest (at pH 4). The fungus therefore dissolves olivine by interacting with the oxidised Fe at the olivine surface. However, Fe uptake did not seem to be involved: mutants deficient in various Fe uptake mechanism dissolved olivine at the same rate as the WT. This indicates that Fe adsorption onto melanin might play a key role. This is also shown by K. petricola’s ability to enhance olivine dissolution even further if secreting a melanin precursor and A. resinae’s corrosion of carbon steel whilst secreting melanin. Combined, our results imply that the Fe adsorbed to melanin cannot be taken up but enables fungi to deteriorate Fe-containing substrates at a higher rate. T2 - Goldschmidt 2023 Conference CY - Lyon, Frankreich DA - 10.07.2023 KW - MIC KW - Bio-weathering KW - Olivine PY - 2023 AN - OPUS4-58523 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gorbushina, Anna T1 - Black fungi on technosphere surfaces: new niches for roof-inhabiting cousins N2 - Human-made systems, also called “build environment” or “technosphere”, sustain human comfort as well as our industrial activities. These systems have become particularly widespread since the Industrial Revolution, i.e., since the 17th century. At the same time, these technical systems – buildings, monuments, energy production, transformation and transmission, water purification and supply systems - serve as new habitats for living organisms. Life is ubiquitously present on our planet since a very long time: the Earth is 4.54 billion years old and microbial communities have played a key role on our planet for 3.7 billion years. Once human-made system appeared, microorganisms became an integral part of all types of technosphere infrastructure as well. Here we will illustrate biosphere-technosphere interactions using a specific example of the black fungi and their impact on the efficiency of solar (photovoltaic) panels. This expanding renewable infrastructure for electricity generation is growing on all continents - and create a specific, arid habitat for stress-tolerant black fungi. Black fungi were once discovered in hot and cold natural deserts – and now belong to the persistent colonisers of human-made deserts of solar parks. This new niche is evolving an impressive biodiversity. So far more than 60 isolates of black fungi belonging to Arthoniomycetes, Eurotiomycetes and Dothideomycetes were obtained from solar panels in Europe and Americas. Here we will present the analysis of this emerging anthropogenic biodiversity. Opportunities for future research in the field include quantification of the microbial load on technosphere surfaces – along with characterisation of the corresponding microbial diversity. The strategy of precise measurement and characterisation will enable us to reliably determine the beneficial and harmful functions that living microorganisms play in the functioning of energy-generating systems – and technosphere in general. T2 - IUBMB Focused Meeting on Extremophilic Fungi (FUN-EX) CY - Ljubljana, Slovenia DA - 19.09.2923 KW - Biosphere-technosphere interaction KW - Microbial communities KW - Solar parks PY - 2023 AN - OPUS4-58451 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - THES A1 - Erdmann, Eileen A. T1 - Genetic tools for targeted genome editing and random mutagenesis of the rock-inhabiting black fungus Knufia petricola N2 - Rock-inhabiting black fungi are ubiquitously found on sun-exposed natural and human-made surfaces. These stresstolerant biofilm-formers are known to force the deterioration of the colonized surfaces. Black fungi belong to different classes of Ascomycota (Arthoniomycetes, Eurotiomycetes, and Dothideomycetes) but evolved the same morpho-physiological adaptations such as strong melanized multilayered cell walls and slow yeast-like or meristematic growth to resist extreme environmental conditions. The rock-inhabitant Knufia petricola was chosen as representative of the polyphyletic group of black fungi for studying mineral weathering, biofilm formation, and interaction with phototrophic microbes. For understanding the molecular basis of these traits, the genetic information and its regulation must be explored. Thus, the genome was sequenced, first -omics datasets obtained and protocols for the transformation of protoplasts and CRISPR/Cas9-based genome editing were implemented to enable genetic studies. In scope of this work, the transformation protocol was optimized to improve the regeneration of K. petricola protoplasts. The successful implementation of multiplexed CRISPR/Cas9 and three additional selection marker systems (geneticin/nptII, glufosinate/bar, chlorimuron ethyl/sur) extended the existing strategies for targeted genome editing. While in the first promoter studies only constitutive promoters (PoliC, PgpdA) were identified as appropriate for expression of fluorescent reporter genes in K. petricola, the functionality of an inducible promoter (synthetic TET-on promoter system) could later be demonstrated. The identification and validation of defined genomic insertion sites enabled the neutral or color-based selection (igr1-5 or pks1, phs1, ade2) as well as the detection of correctly integrated expression constructs. Using the color-based transformant screening (black – pink/white/rose) accelerated the selection of transformants, especially for localization and protein-protein interaction studies (e.g., by studying bimolecular fluorescence complementation). Additionally, the fusion of two or three genes via the viral P2A motif was shown to allow the expression of multiple genes from a single expression cassette/integration site. Finally, the established tools enabled the implementation of a forward genetics tool (customized Ac/Ds transposon system) for regulatable in-vivo mutagenesis of K. petricola. The isolation and characterization of revertants/Ds reinsertion mutants demonstrated the functionality of the system which marks an important milestone for assigning functions to yet unknown species- and/or trait-specific genes. In sum, the genetic engineering toolbox is now fully equipped which paves the way for exploring the biology of K. petricola and other black fungi. KW - Microcolonial fungi KW - Genetic engineering KW - CRISPR/Cas9-mediated genome editing KW - DHN melanin KW - Transposon mutagenesis PY - 2024 SP - 1 EP - 231 CY - Berlin AN - OPUS4-62364 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gerrits, Ruben T1 - Genetic engineering of melanised fungi to study the role of melanin in mineral weathering and metal corrosion N2 - Melanins are organic, dark pigments produced by many organisms. Fungi either fix these pigments in their cell wall or secrete them into their environment to protect themselves against an array of physicochemical stresses (e.g., UV irradiation, desiccation, ...). However, melanins can also adsorb metals like iron and therefore might have a role in the fungal capacity to deteriorate iron-containing minerals and metals. To study this, we focus on the fungi Knufia petricola, a rock-inhabiting fungus with melanised cell walls which deteriorates minerals, and Amorphotheca resinae, a soil-borne fungus able to secrete melanin, degrade alkane-containing fuels, and corrode metals. The broader significance of this work lies in the mitigation of climate change via the negative emission technology enhanced rock weathering for the former to the mitigation of corrosion of biofuel infrastructure for the latter. Genes of K. petricola involved in melanin synthesis and iron uptake were deleted and down- and up- regulated to generate strains with a different melanin content and ability to take up iron. These strains and the wild type (WT) were exposed to a growth solution containing the iron-magnesium silicate olivine of which dissolution rates were obtained by measuring aqueous Mg concentrations using ICP-OES. Thus, the specific mineral deterioration mechanisms of melanised fungi were identified. Abiotically, these experiments showed that iron oxidation at the surface inhibits olivine dissolution. K. petricola was able to enhance dissolution when this abiotic inhibition is strongest (at pH 6) but prevented dissolution when this inhibition is weakest (at pH 4). The fungus therefore dissolves olivine by interacting with the oxidised iron at the olivine surface. Its iron uptake pathways do not seem to be involved as mutants deficient in iron uptake dissolved olivine at the same rate as the WT. The higher dissolution rates of a mutant which secretes a melanin precursor and the lower rates of a melanin-deficient mutant, however, indicate that the iron-adsorbing and -reducing capacities of melanin play a key role. This hypothesis is further supported by carbon steel corrosion experiments with six strains of A. resinae isolated from anthropogenic and natural environments. Their varying ability to secrete melanin correlated with their corrosion rates. We now plan to develop CRISPR/Cas9-mediated genome editing techniques for A. resinae to figure out whether this correlation is also a causation. In summary, our data show that the iron-binding capacity of melanins enables fungi to deteriorate iron-containing substrates at a higher rate. T2 - IBBS19 CY - Berlin, Germany DA - 09.09.2024 KW - Black fungi KW - Weathering KW - Corrosion PY - 2024 AN - OPUS4-61171 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dehkohneh, Abolfazl T1 - From microscale to macroscale: how environmental conditions impact the growth of the black fungus Knufia petricola N2 - Environmental, black fungi are known for their oligotrophic lifestyle and melanin production and ubiquitous colonisers of natural and anthropogenic subaerial surfaces like marble monuments, washing machine soap dispensers and solar panels. Even though their growth is generally unappreciated, prevention or inhibition thereof is still to be accomplished. We have chosen the black fungus Knufia petricola as a model species to study these organisms as it is genetically amenable, able to colonise and deteriorate minerals and produces extracellular polymeric substances allowing attachment. Our goal is simple: the quantitative description of its growth on various environmental conditions to create a mathematical model which could allow the development of a mitigation strategy. The conditions to be tested are the quantity and type of carbon and nitrogen sources, the pH and the presence of neighbouring colonies. The mathematical model is in development using the iDynoMiCS 2.0 platform. Our first results showed that the growth rate is negatively correlated to the colony forming units (i.e. the presence of a neighbouring colony). Although interesting with respect to mitigation, we therefore have chosen to track the growth of single colonies. On a macro-scale, the highest extension rates of colonies were at pH 5, 0.01M NO3, 0.01M NH4, 0.1M glucose, and 0.1M sucrose. Interesting are the similar rates in the range of 0.01M to 0.1M for carbon, and that CO2 production on similar conditions correlates well with these results. On a microscale, we have followed the growth of single cells using a custom-made microfluidic flow cell. Overall, first results show that medium containing more carbon not necessarily affected the growth rate but rather the quantity of branches produced by a single cell. This rapidly results in a more compact microcolony versus the more extended colonies on C-deficient media. This more profound knowledge on the growth of black fungi will allow to dissect their role in material deterioration and colonisation. T2 - International Biodeterioration & Biodegradation Society (IBBS) CY - Berlin, Germany DA - 09.09.2024 KW - Black fungi KW - Rock-inhabiting fungi KW - Fungal biofilm KW - Individual-based modelling PY - 2024 AN - OPUS4-62141 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nitsche, Sarah T1 - The role of the stress-activated MAP kinase SAK1 in Knufia petricola N2 - Mitogen-activated protein (MAP) kinases are highly conserved in animals, plants, and fungi and represent fundamental parts of signaling networks in eukaryotic cells. Black DHN (1,8-dihydroxynaphthalene) melanin and orange carotenoids are produced by many fungi in specific cell types/under certain conditions for protecting cells from abiotic and/or biotic stresses. Microcolonial black fungi constitutively produce DHN melanin, contain the conserved carotenogenic gene cluster, exhibit slow yeast-like growth and survive in extreme environments. Thus, the question arises to which extent pigment formation and responses mediated by the stress-activated MAP kinase module contribute to the observed extremotolerance. We address this question in the rock inhabitant Knufia petricola, the only representative of the extremotolerant black fungi that is genetically amendable. Here, the mutations of pks1, phs1 and both genes result in melanin-free (pink), carotenoid-free (black) and pigment-free (white) strains, respectively (Voigt Knabe et al. 2020, Sci Rep). The gene encoding the stress-activated MAP kinase was deleted in the wild-type and different pigment-deficient backgrounds. In addition, strains were generated that express a GFP-SAK1 fusion protein from the sak1 locus to follow the cytosolic/nuclear shuttling of SAK1 upon stress. Growth of the obtained single, double and triple deletion mutants was tested by dropping cell suspensions on solid media supplemented with different stress-inducing agents. The Δsak1 mutants show slightly reduced growth rates even under non-stress conditions and are hypersensitive to different stress conditions: reduced growth is observed on media inducing, for instance, osmotic, oxidative, membrane, and pH stress, and upon incubation at 30 °C (heat stress). Melanin-free Δsak1 mutants are more sensitive than black Δsak1 mutants to some but not all stress conditions, suggesting that melanin and the SAK1 pathway have complementary roles in protecting K. petricola from stress. T2 - VAAM Fachgruppentragung "Molecular Biology of Fungi" CY - Kaiserslautern, Germany DA - 07.09.2022 KW - Fungus KW - Extremotolerance KW - Signal transduction PY - 2022 AN - OPUS4-55677 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gerrits, Ruben T1 - Quantifying and modelling growth of a subaerial black fungus N2 - Environmental, black fungi are known for their oligotrophic lifestyle and melanin production and are ubiquitous colonisers of natural and anthropogenic subaerial surfaces like marble monuments, washing machine soap dispensers and solar panels. Even though their growth is generally unappreciated, prevention or inhibition thereof is still to be accomplished. We have chosen the genetically amenable, black fungus Knufia petricola as a model species to study these organisms. Our goal is simple: the quantitative description of its growth on various environmental conditions to create a mathematical model using the iDynoMiCS 2.0 platform which could allow the development of a mitigation strategy. The conditions to be tested are the quantity and type of carbon and nitrogen sources, the pH and the presence of neighbouring colonies. First results showed that colonies grown on agar have the highest extension rates at pH 5, 0.01M NO3 or NH4, and 0.1M glucose or sucrose. Interestingly, extension rates but also CO2 production was unaffected by an increase in the concentration of the C-source from 0.01M to 0.1M. On a microscale, we observed that medium containing more C resulted in a higher quantity of branches produced by a single cell and not in a higher single cell growth rate. This rapidly results in a more compact microcolony versus the more extended colonies on C-deficient media. We believe that such deeper knowledge on the growth of black fungi will help mitigate their material colonisation and deterioration. T2 - IMC12 CY - Maastricht, Netherlands DA - 09.08.2024 KW - Black fungi KW - Modelling KW - Carbon and nitrogen limitation PY - 2024 AN - OPUS4-61170 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Frelih, Milena T1 - Material-Microbiome Interactions N2 - Estimations show that the anthropogenic mass, the technosphere, already exceeds the biomass on Earth. Understanding the technosphere-environment interactions and their impacts is key to safe and healthy ecosystems and human societies. At BAM, we aim at promoting awareness for microorganisms living and evolving in contact with human-made materials and technical systems. We are creating datasets of biofilms on plastic and other anthropogenic materials and in the context of important technical challenges (e.g. microbially influenced corrosion or biocide-induced antimicrobial resistance). This enables us to identify and examine key organisms in the investigated systems that potentially harbor new, also industrially relevant, species and traits. Further, we explore material effects on aquatic microbial communities, aiming at the development and establishment of innovative and environmentally relevant methodologies. By using bioinformatic and molecular tools and interdisciplinary research, we enhance the understanding of material-microbiome interactions for a safe and sustainable future. T2 - NFDI4Microbiota Annual Conference CY - Cologne, Germany DA - 30.09.2025 KW - Microbiome KW - Microplastics KW - Black fungi KW - Nanoparticles PY - 2025 AN - OPUS4-64637 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schumacher, Julia T1 - Rock-EATING FUNGI - Genetic Dive into the Biology of the Microcolonial Black Fungus Knufia petricola N2 - Microcolonial black fungi are a group of ascomycetes that exhibit high stress tolerance, yeast‑like growth and constitutive melanin formation. They dominate a range of hostile natural and man‑made environments, from desert rocks and salterns to dishwashers, roofs and solar panels. Due to their slow growth and a lack of genetic tools, the underlying mechanisms of black fungi’s phenotypic traits have remained largely unexplored. We chose to address this gap by genetically engineering the rock‑inhabiting fungus Knufia petricola (Eurotiomycetes, Chaetothyriales), a species that exhibits all characteristics of black fungi. The state‑of‑the‑art genetic toolkit, together with the annotated genome sequence of strain A95, firmly established K. petricola as a model for exploring microcolonial black fungi. T2 - VAAM-Jahrestagung 2021 CY - Online meeting DA - 18.03.2021 KW - Fungus KW - Genetics KW - Marble PY - 2021 AN - OPUS4-52496 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schumacher, Julia T1 - Genetic engineering of black fungi: lessons learned from Knufia petricola N2 - The exponential rise in the number of fungal genomes sequenced by next-generation sequencing techniques makes it necessary to increase efforts to correctly annotate and assign gene functions. There are two possibilities to explore a genome and its gene functions. The hypothesis-based method proves the function of already existing gene/allele candidates by targeted mutagenesis - so called reverse genetics. The basis of forward genetics approaches is the random mutagenesis of the genome, followed by screening of obtained mutants for the phenotype of interest, and identification of the mutated genes in the respective mutants. This strategy is hypothesis-generating, means it is necessary to verify the relationship between the detected mutations and the observed phenotype by targeted mutagenesis of the identified gene. We developed a toolbox for editing the genome of the rock inhabitant Knufia petricola [Eurotiomycetes, Chaetothyriales] that allows the study of the phenotypic characteristics of black fungi such as the regulation of pigment synthesis, general stress responses, oligotrophy, and the unusual modes of cell division by advanced reverse and forward genetics approaches. The toolbox includes the annotated genome sequence of strain A95, efficient strategies for CRISPR/Cas9-based genome editing and live-cell imaging using genetically encoded fluorescent proteins, as well as protocols for -omics approaches and for simulation of mineral weathering. A forward genetics approach using transposon mutagenesis is currently developed for identifying essential genes. The established protocols and knowledge gained from K. petricola form a starting point for making other fungi from extreme environments accessible to genetic manipulation. T2 - IUBMB Focused Meeting on Extremophilic Fungi (FUN-EX) CY - Ljubljana, Slovenia DA - 19.09.2023 KW - Fungus KW - Extremotolerance KW - Genetics KW - Model organism PY - 2023 AN - OPUS4-58424 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gorbushina, Anna T1 - Biofilms in transition: from unwanted layer to material actor N2 - Biofilms on material surfaces have long been regarded as unwanted biological layers and deposits — a kind of living patina. As our knowledge of them is growing, their role is currently undergoing transformation, revealing surprising capacities for problem-solving and material alteration and design. Together, we can explore new perspectives on the interplay between vitality, materiality, and design, challenging conventional boundaries between nature, technology, and aesthetics. T2 - https://www.matters-of-activity.de/en/activities/17716/materials-and-materialities-critical-conversations-across-the-humanities-and-sciences CY - Berlin, Germany DA - 16.10.2025 KW - Reference organisms KW - Reproducible experiments KW - Model biofilms PY - 2025 AN - OPUS4-64495 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schumacher, Julia T1 - Photoperception in plant- and rock-associated black fungi N2 - Fungi that share light-flooded habitats with phototrophs may profit from their excess photosynthetic products. Sunlight-associated stresses are however multiple: high temperatures, UV radiation with associated DNA damage, accumulation of reactive oxygen species (ROS), desiccation and osmotic stresses. Ascomycota dominating light-flooded habitats accurately sense and respond to changes in light using it as a cue to coordinate growth, stress responses as well as to establish pathogenic or symbiotic relationships. Two species from two light-flooded habitats – phyllosphere and sun-exposed solid surfaces – were analysed for their photoreceptor distribution. In both habitats phototroph-associated and black [dihydroxynaphthalene (DHN) melanin-containing] fungi are prevalent. This diversity was sampled with the plant-associated fungus Botrytis cinerea (Leotiomycetes), while Knufia petricola (Eurotiomycetes) was included as a typical biofilm-former on sun-exposed solid surfaces e.g. rocks, building facades, roofs, and solar panels. The analysis has shown that genomes of black fungi contain more photoreceptors than animal pathogens and saprophytes such as Aspergillus nidulans and Neurospora crassa1,2. B. cinerea that causes the grey mould disease by infecting the above-ground parts of more than 200 dicots has a highly sophisticated photosensory and signalling system that helps to avoid light and to locate susceptible hosts1. Rock-inhabiting Dothideomycetes and Eurotiomycetes including Knufia petricola possess equal numbers of photoreceptors along with the same set of protective metabolites i.e. melanin, carotenoids and mycosporines2. This similarity between black fungi from plant and rock surfaces suggests that photoperception and -regulation are important for sun-stressed fungi that receive nutrients through cooperation with phototrophs. CRISPR/Cas9-based genetic tools for manipulating K. petricola were established3 and are currently used for elucidating the functions of the different photoreceptors in the biology of rock-inhabiting fungi. This work was supported by the grant SCHU 2833/4-1 from the German Research Foundation (DFG) and internal funds of the BAM. T2 - 19th Congress of the European Society for Photobiology CY - Online meeting DA - 30.08.2021 KW - Fungi KW - Light KW - Extreme environments PY - 2021 AN - OPUS4-53191 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schumacher, Julia T1 - Fungi in extreme habitats: Lessons from the microcolonial black fungus Knufia petricola N2 - Fungi that share light-flooded habitats with phototrophs may profit from their excess photosynthetic products. But to cope with sunlight-associated stresses [e.g. high temperatures, UV radiation with associated DNA damage, accumulation of reactive oxygen species (ROS), desiccation and osmotic stresses] it is important for fungi to accurately sense and respond to changes in light. The genomes of black [dihydroxynaphthalene (DHN) melanin-containing] fungi from phyllosphere and exposed solid surfaces contain multiple photoreceptors (PRs). The plant pathogen Botrytis cinerea (Leotiomycetes) has a highly sophisticated photosensory and signalling system that helps to avoid light and to locate susceptible hosts. Rock-inhabiting Dothideomycetes and Eurotiomycetes including Knufia petricola possess equal numbers of PRs along with the same set of protective pigments. This similarity between black fungi from plant and rock surfaces suggests that photoperception and -regulation are important for fungi that receive nutrients through cooperation with phototrophs. T2 - Gordon Research Conference "Cellular and Molecular Fungal Biology" CY - Holderness, NH, USA DA - 26.06.2022 KW - Light KW - Stress KW - Photoperception KW - Pigments PY - 2022 AN - OPUS4-55249 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schumacher, Julia T1 - Light-dependent development in Botrytis cinerea N2 - Sunlight is an important environmental factor is almost all ecosystems by being a source of energy, information, and stress. All organisms must protect themselves from the harmful effects of light such as UV radiation, ROS accumulation, heat, and desiccation. Finally, light qualities and quantities can be used for decision making, timing and as guide for directed growth when they are sensed and transduced into intracellular signals. Botrytis cinerea and other plant pathogens infecting the sun-exposed parts of the plant must cope with the high light conditions the host plant seeks. Further they experience an altered light spectrum (‘green gap’) when they colonize shaded parts of the plant; it is depleted for blue and red light that is absorbed by the plant chlorophyll and enriched for green and far-red light that is reflected or transmitted by the plant tissue. As these ambient light conditions trigger the shade avoidance response in the plant, the pathogens may trigger their own ‘shading response’ such as the upregulation of virulence determinants and inoculum production. B. cinerea maintains a highly sophisticated light signaling machinery that senses different light qualities to trigger a variety of responses, that are protection, morphogenesis, positive and negative tropisms, and entrainment. These characteristics render B. cinerea a valuable model to enlighten the role of light in parasitic fungus-plant interactions and beyond. The vegetative mycelium – the core of all infection and developmental programs – is not visibly pigmented and thus considered to be sensitive to biotic and abiotic stresses. However, the vegetative hyphae have a very limited half-life and are usually restricted to the invasive growth phase in which they are protected from light by the plant tissue. Fast colonization of host tissues and by this proper nutrient acquisition enables the rapid formation of long-lasting reproduction structures (melanized conidiophores with conidia, sclerotia) on the surfaces of rotted plant tissues. Depending on the light and temperature conditions, conidiation or sclerotial development is initiated. Taken together, B. cinerea uses light-regulated signaling networks to avoid light whenever possible; for example, by minimizing the half-life of sensitive cells that are hiding in plant tissues and by scheduling critical steps such as conidiogenesis, conidial germination and penetration of plant tissues for the night. T2 - BotrySclero2022 CY - Avignon, France DA - 13.06.2022 KW - Fungus KW - Light KW - Stress KW - Melanin PY - 2022 AN - OPUS4-55248 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Erdmann, Eileen T1 - Tools for Reverse and Forward Genetics in Knufia petricola N2 - Microcolonial black fungi are inhabitants of exposed natural and man-made surfaces in all climate zones. Genetic studies are hampered by slow growth, lacking sexual cycles and difficulties to transform these fungi. Recently, we implemented CRISPR/Cas9-based genetic tools enabling efficient targeted mutations of the rock inhabitant Knufia petricola (Eurotiomycetes/Chaetothyriales) for studying stress responses, the unusual types of cell division, mineral weathering and symbiotic interactions with phototrophic microbes (Voigt, Knabe et al. 2020, Sci Rep; Erdmann et al. 2022, Front Fungal Biol). To further explore the genome of this fungus as representative of the polyphyletic group of black fungi and to assign functions to yet unknown genes, a forward genetics approach is aimed. We chose the two-component Activator/ Dissociation (Ac/Ds) transposon system from maize for generating a collection of insertional mutants by in-vivo mutagenesis. For the optimal use of this genetic tool, an inducible promoter for the expression of the Ac transposase and by this the regulatable transposition of the resistance cassette-containing Ds transposon is requested. However, endogenous promoters for nitrate assimilation and galactose catabolism that are often used in fungi for regulatable gene expression are not inducible by their substrates in K. petricola suggesting that the regulatory networks for nutrient acquisition differ significantly in the oligotrophic black fungi. Therefore, the metabolism-independent Tet-on system was adopted and validated using a Ptet::gfp construct. No GFP fluorescence was detected in absence of the inducer doxycycline (DOX) while fluorescence intensities increased with increasing inducer concentrations. Consequently, the Tet-on system is suitable for regulatable expression of endogenous and foreign genes in K. petricola. T2 - VAAM Fachgruppentagung "Molecular Biology of Fungi" CY - Kaiserslautern, Germany DA - 07.09.2022 KW - Rock-inhabiting fungus KW - Genetic tools KW - Controllable gene expression PY - 2022 AN - OPUS4-55678 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schumacher, Julia T1 - DHN melanin synthesis in the rock inhabitant Knufia petricola N2 - DHN (1,8-dihydroxynaphthalene) melanin is produced by different Ascomycetes via slightly differing biosynthetic routes. The polyketide synthases (PKS) release the heptaketide YWA1, the hexaketide AT4HN or the pentaketide T4HN. The first two products are deacetylated by ‘yellowish-green’ hydrolases to T4HN, and T4HN is further converted by a core set of enzymes to DHN. Final polymerization steps are accomplished by multicopper oxidases (MCOs). The involved genes are tightly clustered, partially clustered or widely distributed in the genomes of DHN melanin-producing fungi. DHN melanogenesis is often regulated in a spatial and temporal fashion resulting e.g. in melanized reproduction, survival and/or infection structures. In contrast, a polyphyletic group of Ascomycetes (microcolonial fungi/ black yeast) dwelling in hostile habitats such as bare rock surfaces in hot and cold deserts, exhibits constitutive melanogenesis. Here, we report on the identification and functional characterization of the DHN melanogenic genes of Knufia petricola as a representative of the Chaetothyriales, the sister order of the Eurotiales. Orthologs for all melanogenic genes were identified in the genome of K. petricola A95, including one gene encoding the polyketide synthase (KpPKS1), two genes encoding ‘yellowish-green’ hydrolases (KpYGH1,2), two genes encoding THN reductases (KpTHR1,2) and one gene encoding a scytalone dehydratase (KpSDH1). Ten genes encoding MCOs were identified, all MCOs are predicted to be secreted. The genes are not clustered in the genome but are highly expressed. Gene functions are studied by generation of single, double, and multiple deletion mutants in K. petricola and by heterologous expression in Saccharomyces cerevisiae for reconstruction of the synthesis pathway. T2 - VAAM Fachgruppentagung "Molecular Biology of Fungi" CY - Kaiserslautern, Germany DA - 07.09.2022 KW - DHN melanin KW - Genetics KW - Biodegradation PY - 2022 AN - OPUS4-55676 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gerrits, Ruben T1 - Iron uptake by the rock-inhabiting fungus Knufia petricola N2 - Iron is arguably the most essential metal in living organisms. For rock-inhabiting fungi its acquisition might be unconventional as they (1) tend to inhabit iron-deficient, oxygen-rich surfaces like marble monuments and solar panels and (2) produce the black, iron-adsorbing pigment melanin. We used a range of analytical methods, ongoing mineral dissolution experiments and gene deletion mutants of the model rock-inhabiting fungus Knufia petricola to figure out the mechanisms and substrate deteriorating effects of iron uptake by these organisms. To study both siderophore-mediated and reductive iron assimilation (RIA), genes like sidC, encoding a putative siderophore synthetase and ftr1 and fet3 encoding the subunits of an iron permease-oxidase were deleted. At iron deficient conditions, growth of the wild type (WT) and ΔsidC mutant was similar, whereas growth of the Δftr1-fet3 mutant and the double mutant ΔsidC/Δftr1-fet3 was diminished and absent, respectively. We were not able to detect the siderophore of K. petricola and the WT and mutants were not able to grow at low concentrations of strong iron chelators. However, in a cross-feeding experiment, an overexpression strain of sidC allowed more growth of ΔsidC/Δftr1-fet3 on iron deficient medium than the WT, whereas the ΔsidC mutant could not do so at all. Compared to the WT, the sidC overexpression strain also withstood oxidative stress better and had a shorter lag time and higher growth rate. Combined, these results indicate that K. petricola relies more on RIA than siderophore-mediated uptake as it likely excretes low quantities of a primarily intracellular siderophore. Interestingly, Δftr1-fet3 had a higher iron content than the WT at iron deficient conditions. This difference disappeared upon deletion of melanin synthesis (Δpks1 vs. Δpks1/Δftr1-fet3): melanin-bound iron can likely not be used without RIA. K. petricola’s chelation incapacity implies a habitat free of competition for iron while offering us a mitigation strategy. T2 - ECFG16 CY - Innsbruck, Austria DA - 05.03.2023 KW - Siderophore KW - Melanin KW - Reductive iron assimilation PY - 2023 AN - OPUS4-57148 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dehkohneh, Abolfazl T1 - From microscale to macroscale: environmental conditions and growth patterns of the black fungus Knufia petricola N2 - Environmental, black fungi are known for their oligotrophic lifestyle and melanin production and ubiquitous colonisers of natural and anthropogenic subaerial surfaces like marble monuments, washing machine soap dispensers and solar panels. Even though their growth is generally unappreciated, prevention or inhibition thereof is still to be accomplished. We have chosen the black fungus Knufia petricola as a model species to study these organisms as it is genetically amenable, able to colonise and deteriorate minerals and produces extracellular polymeric substances allowing attachment. Our goal is simple: the quantitative description of its growth on various environmental conditions to create a mathematical model which could allow the development of a mitigation strategy. The conditions to be tested are the quantity and type of carbon and nitrogen sources, the pH and the presence of neighbouring colonies. The mathematical model is in development using the iDynoMiCS 2.0 platform. Our first results showed that the growth rate is negatively correlated to the colony forming units (i.e. the presence of a neighbouring colony). Although interesting with respect to mitigation, we therefore have chosen to track the growth of single colonies. On a macro-scale, the highest extension rates of colonies were at pH 5, 0.01M NO3, 0.01M NH4, 0.1M glucose, and 0.1M sucrose. Interesting are the similar rates in the range of 0.01M to 0.1M for carbon, and that CO2 production on similar conditions correlates well with these results. On a microscale, we have followed the growth of single cells using a custom-made microfluidic flow cell. Overall, first results show that medium containing more carbon not necessarily affected the growth rate but rather the quantity of branches produced by a single cell. This rapidly results in a more compact microcolony versus the more extended colonies on C-deficient media. This more profound knowledge on the growth of black fungi will allow to dissect their role in material deterioration and colonisation. T2 - CurvoBio 2024 CY - Warsaw, Poland DA - 28.08.2024 KW - Black fungi KW - Rock-inhabiting fungi KW - Fungal biofilm KW - Individual-based modelling KW - Biocorrosion PY - 2024 AN - OPUS4-62270 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -