TY - JOUR A1 - Amalfitano, Stefano A1 - Corno, Gianluca A1 - Eckert, Ester A1 - Fazi, Stefano A1 - Ninio, Shira A1 - Callieri, Cristiana A1 - Grossart, Hans-Peter A1 - Eckert, Werner T1 - Tracing particulate matter and associated microorganisms in freshwaters JF - Hydrobiologia : acta hydrobiologica, hydrographica, limnologica et protistologica N2 - Sediment resuspension represents a key process in all natural aquatic systems, owing to its role in nutrient cycling and transport of potential contaminants. Although suspended solids are generally accepted as an important quality parameter, current monitoring programs cover quantitative aspects only. Established methodologies do not provide information on origin, fate, and risks associated with uncontrolled inputs of solids in waters. Here we discuss the analytical approaches to assess the occurrence and ecological relevance of resuspended particulate matter in freshwaters, with a focus on the dynamics of associated contaminants and microorganisms. Triggered by the identification of specific physical-chemical traits and community structure of particle-associated microorganisms, recent findings suggest that a quantitative determination of microorganisms can be reasonably used to trace the origin of particulate matter by means of nucleic acid-based assays in different aquatic systems. KW - Total suspended solids KW - Resuspended particulate KW - Turbidity KW - Sediment traps KW - Particle-associated microorganisms KW - Pathogens Y1 - 2017 U6 - https://doi.org/10.1007/s10750-017-3260-x SN - 0018-8158 SN - 1573-5117 VL - 800 SP - 145 EP - 154 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Eckert, Ester M. A1 - Di Cesare, Andrea A1 - Kettner, Marie Therese A1 - Arias-Andres, Maria A1 - Fontaneto, Diego A1 - Grossart, Hans-Peter A1 - Corno, Gianluca T1 - Microplastics increase impact of treated wastewater on freshwater microbial community JF - Environmental pollution N2 - Plastic pollution is a major global concern with several million microplastic particles entering every day freshwater ecosystems via wastewater discharge. Microplastic particles stimulate biofilm formation (plastisphere) throughout the water column and have the potential to affect microbial community structure if they accumulate in pelagic waters, especially enhancing the proliferation of biohazardous bacteria. To test this scenario, we simulated the inflow of treated wastewater into a temperate lake using a continuous culture system with a gradient of concentration of microplastic particles. We followed the effect of microplastics on the microbial community structure and on the occurrence of integrase 1 (intl), a marker associated with mobile genetic elements known as a proxy for anthropogenic effects on the spread of antimicrobial resistance genes. The abundance of intl increased in the plastisphere with increasing microplastic particle concentration, but not in the water surrounding the microplastic particles. Likewise, the microbial community on microplastic was more similar to the original wastewater community with increasing microplastic concentrations. Our results show that microplastic particles indeed promote persistence of typical indicators of microbial anthropogenic pollution in natural waters, and substantiate that their removal from treated wastewater should be prioritised. (C) 2017 Elsevier Ltd. All rights reserved. KW - Microplastics KW - Anthropogenic pollution KW - Treated wastewater KW - Freshwater microbial communities KW - Integrase 1 KW - Biofilm Y1 - 2017 U6 - https://doi.org/10.1016/j.envpol.2017.11.070 SN - 0269-7491 SN - 1873-6424 VL - 234 SP - 495 EP - 502 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Corno, Gianluca A1 - Salka, Ivette A1 - Pohlmann, Kirsten A1 - Hall, Alex R. A1 - Grossart, Hans-Peter T1 - Interspecific interactions drive chitin and cellulose degradation by aquatic microorganisms JF - Aquatic microbial ecology : international journal N2 - Complex biopolymers (BPs) such as chitin and cellulose provide the majority of organic carbon in aquatic ecosystems, but the mechanisms by which communities of bacteria in natural systems exploit them are unclear. Previous degradation experiments in artificial systems predominantly used microcosms containing a single bacterial species, neglecting effects of interspecific interactions. By constructing simplified aquatic microbial communities, we tested how the addition of other bacterial species, of a nanoflagellate protist capable of consuming bacteria, or of both, affect utilization of BPs. Surprisingly, total abundance of resident bacteria in mixed communities increased upon addition of the protist. Concomitantly, bacteria shifted from free-living to aggregated morphotypes that seemed to promote utilization of BPs. In our model system, these interactions significantly increased productivity in terms of overall bacterial numbers and carbon transfer efficiency. This indicates that interactions on microbial aggregates may be crucial for chitin and cellulose degradation. We therefore suggest that interspecific microbial interactions must be considered when attempting to model the turnover of the vast pool of complex biopolymers in aquatic ecosystems. KW - Aggregation KW - Flagellate grazing KW - Ecological interactions KW - Microbial carbon transfer KW - Polymer degradation KW - System ecology Y1 - 2015 U6 - https://doi.org/10.3354/ame01765 SN - 0948-3055 SN - 1616-1564 VL - 76 IS - 1 SP - 27 EP - + PB - Institute of Mathematical Statistics CY - Oldendorf Luhe ER -