TY - JOUR A1 - Richter, Anja A1 - Possling, A. A1 - Malysheva, N. A1 - Yousef, K. P. A1 - Herbst, S. A1 - von Kleist, M. A1 - Hengge, R. T1 - Local c-di-GMP signaling in the control of synthesis of the E. coli biofilm exopolysaccharide pEtN-cellulose N2 - In many bacteria, the biofilm-promoting second messenger c-di-GMP is produced and degraded by multiple diguanylate cyclases (DGC) and phosphodiesterases (PDE), respectively. High target specificity of some of these enzymes has led to theoretical concepts of "local" c-di-GMP signaling. In Escherichia coli K-12, which has 12 DGCs and 13 PDEs, a single DGC, DgcC, is specifically required for the biosynthesis of the biofilm exopolysaccharide pEtN-cellulose without affecting the cellular c-di-GMP pool, but the mechanistic basis of this target specificity has remained obscure. DGC activity of membrane-associated DgcC, which is demonstrated in vitro in nanodiscs, is shown to be necessary and sufficient to specifically activate cellulose biosynthesis in vivo. DgcC and a particular PDE, PdeK (encoded right next to the cellulose operon), directly interact with cellulose synthase subunit BcsB and with each other, thus establishing physical proximity between cellulose synthase and a local source and sink of c-di-GMP. This arrangement provides a localized, yet open source of c-di-GMP right next to cellulose synthase subunit BcsA, which needs allosteric activation by c-di-GMP. Through mathematical modeling and simulation, we demonstrate that BcsA binding from the low cytosolic c-di-GMP pool in E. coli is negligible, whereas a single c-di-GMP molecule that is produced and released in direct proximity to cellulose synthase increases the probability of c-di-GMP binding to BcsA several hundred-fold. This local c-di-GMP signaling could provide a blueprint for target-specific second messenger signaling also in other bacteria where multiple second messenger producing and degrading enzymes exist. KW - Biofilm KW - Cellulose synthase KW - Bacterial second messenger KW - C-di-GMP PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-511214 DO - https://doi.org/10.1016/j.jmb.2020.06.006 SN - 0022-2836 VL - 432 IS - 16 SP - 4576 EP - 4595 PB - Elsevir Ltd. AN - OPUS4-51121 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, S. A1 - Herbst, Tristan A1 - Lenz, K. A1 - Wittstock, B. A1 - Bos, U. A1 - Sedlbauer, K. T1 - Recycling options for masonry - Identifying sustainable solutions N2 - Almost 15% of the average yearly waste accumulation in Germany originates from construction waste. It mainly comprises mineral materials such as concrete and different types of stonework, like lime-sandstone, red brick, aerated concrete and lightweight concrete. Due to the heterogeneous material composition, this kind of waste often ends up in landfill or can only be used for lower-level recycling. The AiF (German Federation of Industrial Research Association) funded the national research project "Sustainability Analysis for the Recycling of Masonry" in order to show different recycling opportunities for masonry as well as respective required technologies with regard to potential occurring mineral material mixtures. Technologies identified are for example such ones to break masonry into smaller grain sizes and technologies to separate the masonry into single material fractions. Furthermore, the project has the objective to assess the sustainability performance of various recycling options. These options and the related recycling routes are evaluated regarding environmental, economic and social aspects - all three pillars of sustainability - by using the methods of Life Cycle Assessment (LCA), Life Cycle Costing (LCC) and Life Cycle Working Environment (LCWE). The results are provided within a web-tool for operators of recycling facilities and for demolition companies. Its modular concept affords an individual sustainability assessment by several input options, like machine capacity, investment costs and achievable revenues. The tool enables the user to assess and compare different recycling opportunities concerning environmental, economic and social aspects in relation to identified material compositions and technologies applied. T2 - sb13 munich - Sustainable building conference CY - Munich, Germany DA - 24.04.2013 KW - Sustainability KW - LCA KW - LCC KW - LCWE KW - Recycling KW - Demolition material PY - 2013 SN - 978-3-8167-8965-9 SP - 387 EP - 388 PB - Fraunhofer IRB-Verl. AN - OPUS4-28639 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, S. A1 - Beck, T. A1 - Wittstock, B. A1 - Herbst, Tristan T1 - Sustainability assessment for the recycling of masonry N2 - In Germany, construction debris, road construction waste and excavated material amount to 60% of the total waste. The construction debris originates mainly from Building demolition and comprises of concrete and different types of masonry such as red brick, lime-sandstone, aerated concrete and lightweight concrete, but also other materials such as insulation material, gypsum, plaster, tiles, wood, Steel and plastics. Due to the large amount of building demolition material, the recycling of masonry to high-quality Recycling Products and closed-loop-recycling bears a high potential to reduce environmental impacts. Within the AiF (German Federation of Industrial Research Association) research Project “Sustainability Assessment for the Recycling of Masonry”, different recycling Technologies will be assessed with regard to their sustainability performance. All three pillars of sustainability - the ecological, the economic and the social pillar - will be considered, using the methods of Life Cycle Assessment (LCA), Life Cycle Costing (LCC) and Life Cycle Working Environment (LCWE). The assessment will be carried out for different Recycling technologies, for common ones but also for such technologies that are not yet in large scale application. The applicability of technologies depends on the type of the demolition material and on the purity of variety. One part of the research project is to develop a web-based tool for operators of recycling facilities and for demolition Companies to assess their recycling options. In most cases, demolished masonry has a very heterogeneous material composition, and therefore can only be used for lower-level recycling options or ends up in landfill. The aim of the project is to avoid landfilling and the downcycling of products and to achieve a higher recycling level. Closed-loop-recycling has priority. The main aspects of closed-loop-recycling are to change not the inherent properties of the recycled material and to recycle into the same or other product Systems. In the course of this, it is important to preserve the quality of the recycling material and to ensure a versatile use. To reach this target, different recycling technologies are identified and with the aid of the mentioned methods - LCA, LCC and LCWE - evaluated. In addition to predefined Processing routes, it is possible to assess individual recycling plants. A basic recyclingprinciple is defined to which further System modules can be added. The web-tool enables the user to identify different options - depending on the demolition material and its purity - and yields the sustainability assessment. Thus, the user gets Information about possibilities of the recycling of masonry and the environmental, economic and social Benefits compared to downcycling and landfill. T2 - SAM-6 - 6th International conference on society & materials CY - Leuven, Belgium DA - 30.05.2012 PY - 2012 SN - 1958-2897 SP - 1 EP - 7 AN - OPUS4-28644 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -