TY - JOUR A1 - Toepfer, I. A1 - Favet, J. A1 - Schulte, A. A1 - Schmölling, M. A1 - Butte, W. A1 - Triplett, E.W. A1 - Broughton, W.J. A1 - Gorbushina, Anna T1 - Pathogens as potential hitchhikers on intercontinental dust N2 - Desert dust seeds distant lands and waters with minerals as well as micro-organisms raising the question of whether this ancient phenomenon also spreads pathogens across the globe. Severe dust storms require strong winds blowing over land-masses that are largely devoid of vegetation, effectively limiting the scope for winds to raise pathogens into the air. Nevertheless, changing patterns of land-use, often driven by belligerency, result in refugees spreading to areas that were previously deemed barely habitable. With the help of the International Committee of the Red Cross, a number of sand/dust samples were collected from the Republic of Chad, some near refugee camps, others further removed from human influence. In parallel studies, we documented the micro-organisms present in these samples and used a number of the isolates here to test the effect of environmental constraints on their ability to survive intercontinental flight. We also added traditional pathogens to the palette of microbes and tested the effects of UV irradiation, desiccation and temperature on survival of both bacteria and fungi. A clear trend was obvious—those microbes that are coloured or able to form conidia or spores (in other words, those that are native to deserts) were well able to resist the imposed stresses. On the other hand, most pathogens were more sensitive to stresses than the environmental isolates. Toxin production in two species of Aspergillus was also investigated. Short-term desiccation (simulating environmental conditions during intercontinental travel) of sand amended with fungal spores containing sterigmatocystin leads to increased mycotoxin contents, but significant mycotoxin production was only possible under growth-permissive conditions, e.g. at higher humidity. It thus seems likely that an ever-decreasing fraction of the initial pathogen load survives as the dust recedes from its desert source and that those organisms that land on other continents are highly enriched in desert dwellers. KW - Chad KW - Desert sand KW - Sterigmatocystin KW - Aspergillus sydowii KW - A. versicolor PY - 2012 U6 - https://doi.org/10.1007/s10453-011-9230-2 SN - 0393-5965 SN - 1573-3025 VL - 28 IS - 2 SP - 221 EP - 231 PB - Springer Science + Business Media B.V. CY - Dordrecht [u.a.] AN - OPUS4-24814 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Giongo, A. A1 - Favet, J. A1 - Lapanje, A. A1 - Gano, K.A. A1 - Kennedy, S. A1 - Davis-Richardson, A.G. A1 - Brown, C. A1 - Beck, A. A1 - Farmerie, W.G. A1 - Cattaneo, A. A1 - Crabb, D.B. A1 - Aung, Y.-Y. A1 - Kort, R. A1 - Brumsack, H.-J. A1 - Schnetger, B. A1 - Broughton, William J. A1 - Gorbushina, Anna A1 - Triplett, E.W. T1 - Microbial hitchhikers on intercontinental dust: high-throughput sequencing to catalogue microbes in small sand samples N2 - Microbiological studies on the intercontinental transport of dust are confounded by the difficulty of obtaining sufficient material for analysis. Axenic samples of dust collected at high altitudes or historic specimens in museums are often so small and precious that the material can only be sacrificed when positive results are assured. With this in mind, we evaluated current methods and developed new ones in an attempt to catalogue all microbes present in small dust or sand samples. The methods used included classical microbiological approaches in which sand extracts were plated out on a variety of different media, polymerase chain reaction (PCR)-based amplification of 16S/18S rRNA sequences followed by construction of clone libraries, PCR amplification of 16S rRNA sequences followed by high-throughput sequencing (HtS) of the products and direct HtS of DNA extracted from the sand. A representative sand sample collected at Bahaï Wadi in the desert of the Republic of Chad was used. HtS with or without amplification showed the most promise and can be performed on ≤100 ng DNA. Since living microbes are often required, current best practices would involve geochemical and microscopic characterisation of the sample, followed by DNA isolation and direct HtS. Once the microbial content of the sample has been deciphered, growth conditions (including media) can be tailored to isolate the micro-organisms of interest. KW - Chad KW - Deserts KW - Eukaryota KW - 16S amplicons KW - Metagenomics PY - 2013 U6 - https://doi.org/10.1007/s10453-012-9264-0 SN - 0393-5965 SN - 1573-3025 VL - 29 IS - 1 SP - 71 EP - 84 PB - Springer Science + Business Media B.V. CY - Dordrecht [u.a.] AN - OPUS4-27687 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -