@misc{BeisnerGrossartGasol2019, author = {Beisner, Beatrix E. and Grossart, Hans-Peter and Gasol, Josep M.}, title = {A guide to methods for estimating phago-mixotrophy in nanophytoplankton}, series = {Journal of plankton research}, volume = {41}, journal = {Journal of plankton research}, number = {2}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0142-7873}, doi = {10.1093/plankt/fbz008}, pages = {77 -- 89}, year = {2019}, abstract = {Growing attention to phytoplankton mixotrophy as a trophic strategy has led to significant revisions of traditional pelagic food web models and ecosystem functioning. Although some empirical estimates of mixotrophy do exist, a much broader set of in situ measurements are required to (i) identify which organisms are acting as mixotrophs in real time and to (ii) assess the contribution of their heterotrophy to biogeochemical cycling. Estimates are needed through time and across space to evaluate which environmental conditions or habitats favour mixotrophy: conditions still largely unknown. We review methodologies currently available to plankton ecologists to undertake estimates of plankton mixotrophy, in particular nanophytoplankton phago-mixotrophy. Methods are based largely on fluorescent or isotopic tracers, but also take advantage of genomics to identify phylotypes and function. We also suggest novel methods on the cusp of use for phago-mixotrophy assessment, including single-cell measurements improving our capacity to estimate mixotrophic activity and rates in wild plankton communities down to the single-cell level. Future methods will benefit from advances in nanotechnology, micromanipulation and microscopy combined with stable isotope and genomic methodologies. Improved estimates of mixotrophy will enable more reliable models to predict changes in food web structure and biogeochemical flows in a rapidly changing world.}, language = {en} } @misc{BlockDenfeldStockwelletal.2019, author = {Block, Benjamin D. and Denfeld, Blaize A. and Stockwell, Jason D. and Flaim, Giovanna and Grossart, Hans-Peter and Knoll, Lesley B. and Maier, Dominique B. and North, Rebecca L. and Rautio, Milla and Rusak, James A. and Sadro, Steve and Weyhenmeyer, Gesa A. and Bramburger, Andrew J. and Branstrator, Donn K. and Salonen, Kalevi and Hampton, Stephanie E.}, title = {The unique methodological challenges of winter limnology}, series = {Limnology and Oceanography: Methods}, volume = {17}, journal = {Limnology and Oceanography: Methods}, number = {1}, publisher = {Wiley}, address = {Hoboken}, issn = {1541-5856}, doi = {10.1002/lom3.10295}, pages = {42 -- 57}, year = {2019}, abstract = {Winter is an important season for many limnological processes, which can range from biogeochemical transformations to ecological interactions. Interest in the structure and function of lake ecosystems under ice is on the rise. Although limnologists working at polar latitudes have a long history of winter work, the required knowledge to successfully sample under winter conditions is not widely available and relatively few limnologists receive formal training. In particular, the deployment and operation of equipment in below 0 degrees C temperatures pose considerable logistical and methodological challenges, as do the safety risks of sampling during the ice-covered period. Here, we consolidate information on winter lake sampling and describe effective methods to measure physical, chemical, and biological variables in and under ice. We describe variation in snow and ice conditions and discuss implications for sampling logistics and safety. We outline commonly encountered methodological challenges and make recommendations for best practices to maximize safety and efficiency when sampling through ice or deploying instruments in ice-covered lakes. Application of such practices over a broad range of ice-covered lakes will contribute to a better understanding of the factors that regulate lakes during winter and how winter conditions affect the subsequent ice-free period.}, language = {en} } @article{CookLiCaietal.2019, author = {Cook, Katherine V. and Li, Chuang and Cai, Haiyuan and Krumholz, Lee R. and Hambright, K. David and Paerl, Hans W. and Steffen, Morgan M. and Wilson, Alan E. and Burford, Michele A. and Grossart, Hans-Peter and Hamilton, David P. and Jiang, Helong and Sukenik, Assaf and Latour, Delphine and Meyer, Elisabeth I. and Padisak, Judit and Qin, Boqiang and Zamor, Richard M. and Zhu, Guangwei}, title = {The global Microcystis interactome}, series = {Limnology and oceanography}, volume = {65}, journal = {Limnology and oceanography}, publisher = {Wiley}, address = {Hoboken}, issn = {0024-3590}, doi = {10.1002/lno.11361}, pages = {S194 -- S207}, year = {2019}, abstract = {Bacteria play key roles in the function and diversity of aquatic systems, but aside from study of specific bloom systems, little is known about the diversity or biogeography of bacteria associated with harmful cyanobacterial blooms (cyanoHABs). CyanoHAB species are known to shape bacterial community composition and to rely on functions provided by the associated bacteria, leading to the hypothesized cyanoHAB interactome, a coevolved community of synergistic and interacting bacteria species, each necessary for the success of the others. Here, we surveyed the microbiome associated with Microcystis aeruginosa during blooms in 12 lakes spanning four continents as an initial test of the hypothesized Microcystis interactome. We predicted that microbiome composition and functional potential would be similar across blooms globally. Our results, as revealed by 16S rRNA sequence similarity, indicate that M. aeruginosa is cosmopolitan in lakes across a 280 degrees longitudinal and 90 degrees latitudinal gradient. The microbiome communities were represented by a wide range of operational taxonomic units and relative abundances. Highly abundant taxa were more related and shared across most sites and did not vary with geographic distance, thus, like Microcystis, revealing no evidence for dispersal limitation. High phylogenetic relatedness, both within and across lakes, indicates that microbiome bacteria with similar functional potential were associated with all blooms. While Microcystis and the microbiome bacteria shared many genes, whole-community metagenomic analysis revealed a suite of biochemical pathways that could be considered complementary. Our results demonstrate a high degree of similarity across global Microcystis blooms, thereby providing initial support for the hypothesized Microcystis interactome.}, language = {en} } @article{GrossartMassanaMcMahonetal.2019, author = {Grossart, Hans-Peter and Massana, Ramon and McMahon, Katherine D. and Walsh, David A.}, title = {Linking metagenomics to aquatic microbial ecology and biogeochemical cycles}, series = {Limnology and oceanography}, volume = {65}, journal = {Limnology and oceanography}, publisher = {Wiley}, address = {Hoboken}, issn = {0024-3590}, doi = {10.1002/lno.11382}, pages = {S2 -- S20}, year = {2019}, abstract = {Microbial communities are essential components of aquatic ecosystems through their contribution to food web dynamics and biogeochemical processes. Aquatic microbial diversity is immense and a general challenge is to understand how metabolism and interactions of single organisms shape microbial community dynamics and ecosystem-scale biogeochemical transformations. Metagenomic approaches have developed rapidly, and proven to be powerful in linking microbial community dynamics to biogeochemical processes. In this review, we provide an overview of metagenomic approaches, followed by a discussion on some recent insights they have provided, including those in this special issue. These include the discovery of new taxa and metabolisms in aquatic microbiomes, insights into community assembly and functional ecology as well as evolutionary processes shaping microbial genomes and microbiomes, and the influence of human activities on aquatic microbiomes. Given that metagenomics can now be considered a mature technology where data generation and descriptive analyses are relatively routine and informative, we then discuss metagenomic-enabled research avenues to further link microbial dynamics to biogeochemical processes. These include the integration of metagenomics into well-designed ecological experiments, the use of metagenomics to inform and validate metabolic and biogeochemical models, and the pressing need for ecologically relevant model organisms and simple microbial systems to better interpret the taxonomic and functional information integrated in metagenomes. These research avenues will contribute to a more mechanistic and predictive understanding of links between microbial dynamics and biogeochemical cycles. Owing to rapid climate change and human impacts on aquatic ecosystems, the urgency of such an understanding has never been greater.}, language = {en} } @misc{GrossartVandenWyngaertKagamietal.2019, author = {Grossart, Hans-Peter and Van den Wyngaert, Silke and Kagami, Maiko and Wurzbacher, Christian and Cunliffe, Michael and Rojas-Jimenz, Keilor}, title = {Fungi in aquatic ecosystems}, series = {Nature reviews. Microbiology}, volume = {17}, journal = {Nature reviews. Microbiology}, number = {6}, publisher = {Nature Publ. Group}, address = {Basingstoke}, issn = {1740-1526}, doi = {10.1038/s41579-019-0175-8}, pages = {339 -- 354}, year = {2019}, abstract = {Fungi are phylogenetically and functionally diverse ubiquitous components of almost all ecosystems on Earth, including aquatic environments stretching from high montane lakes down to the deep ocean. Aquatic ecosystems, however, remain frequently overlooked as fungal habitats, although fungi potentially hold important roles for organic matter cycling and food web dynamics. Recent methodological improvements have facilitated a greater appreciation of the importance of fungi in many aquatic systems, yet a conceptual framework is still missing. In this Review, we conceptualize the spatiotemporal dimensions, diversity, functions and organismic interactions of fungi in structuring aquatic food webs. We focus on currently unexplored fungal diversity, highlighting poorly understood ecosystems, including emerging artificial aquatic habitats.}, language = {en} } @article{GuenthelDonisKirillinetal.2019, author = {G{\"u}nthel, Marco and Donis, Daphne and Kirillin, Georgiy and Ionescu, Danny and Bizic, Mina and McGinnis, Daniel F. and Grossart, Hans-Peter and Tang, Kam W.}, title = {Contribution of oxic methane production to surface methane emission in lakes and its global importance}, series = {Nature Communications}, volume = {10}, journal = {Nature Communications}, publisher = {Nature Publishing Group UK}, address = {London}, issn = {2041-1723}, doi = {10.1038/s41467-019-13320-0}, pages = {10}, year = {2019}, abstract = {Recent discovery of oxic methane production in sea and lake waters, as well as wetlands, demands re-thinking of the global methane cycle and re-assessment of the contribution of oxic waters to atmospheric methane emission. Here we analysed system-wide sources and sinks of surface-water methane in a temperate lake. Using a mass balance analysis, we show that internal methane production in well-oxygenated surface water is an important source for surface-water methane during the stratified period. Combining our results and literature reports, oxic methane contribution to emission follows a predictive function of littoral sediment area and surface mixed layer volume. The contribution of oxic methane source(s) is predicted to increase with lake size, accounting for the majority (>50\%) of surface methane emission for lakes with surface areas >1 km(2).}, language = {en} } @article{HegerBernardVerdierGessleretal.2019, author = {Heger, Tina and Bernard-Verdier, Maud and Gessler, Arthur and Greenwood, Alex D. and Grossart, Hans-Peter and Hilker, Monika and Keinath, Silvia and Kowarik, Ingo and K{\"u}ffer, Christoph and Marquard, Elisabeth and Mueller, Johannes and Niemeier, Stephanie and Onandia, Gabriela and Petermann, Jana S. and Rillig, Matthias C. and Rodel, Mark-Oliver and Saul, Wolf-Christian and Schittko, Conrad and Tockner, Klement and Joshi, Jasmin Radha and Jeschke, Jonathan M.}, title = {Towards an Integrative, Eco-Evolutionary Understanding of Ecological Novelty: Studying and Communicating Interlinked Effects of Global Change}, series = {Bioscience}, volume = {69}, journal = {Bioscience}, number = {11}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0006-3568}, doi = {10.1093/biosci/biz095}, pages = {888 -- 899}, year = {2019}, abstract = {Global change has complex eco-evolutionary consequences for organisms and ecosystems, but related concepts (e.g., novel ecosystems) do not cover their full range. Here we propose an umbrella concept of "ecological novelty" comprising (1) a site-specific and (2) an organism-centered, eco-evolutionary perspective. Under this umbrella, complementary options for studying and communicating effects of global change on organisms, ecosystems, and landscapes can be included in a toolbox. This allows researchers to address ecological novelty from different perspectives, e.g., by defining it based on (a) categorical or continuous measures, (b) reference conditions related to sites or organisms, and (c) types of human activities. We suggest striving for a descriptive, non-normative usage of the term "ecological novelty" in science. Normative evaluations and decisions about conservation policies or management are important, but require additional societal processes and engagement with multiple stakeholders.}, language = {en} } @article{KaylerPremkeGessleretal.2019, author = {Kayler, Zachary E. and Premke, Katrin and Gessler, Arthur and Gessner, Mark O. and Griebler, Christian and Hilt, Sabine and Klemedtsson, Leif and Kuzyakov, Yakov and Reichstein, Markus and Siemens, Jan and Totsche, Kai-Uwe and Tranvik, Lars and Wagner, Annekatrin and Weitere, Markus and Grossart, Hans-Peter}, title = {Integrating Aquatic and Terrestrial Perspectives to Improve Insights Into Organic Matter Cycling at the Landscape Scale}, series = {Frontiers in Earth Science}, volume = {7}, journal = {Frontiers in Earth Science}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {2296-6463}, doi = {10.3389/feart.2019.00127}, pages = {14}, year = {2019}, abstract = {Across a landscape, aquatic-terrestrial interfaces within and between ecosystems are hotspots of organic matter (OM) mineralization. These interfaces are characterized by sharp spatio-temporal changes in environmental conditions, which affect OM properties and thus control OM mineralization and other transformation processes. Consequently, the extent of OM movement at and across aquatic-terrestrial interfaces is crucial in determining OM turnover and carbon (C) cycling at the landscape scale. Here, we propose expanding current concepts in aquatic and terrestrial ecosystem sciences to comprehensively evaluate OM turnover at the landscape scale. We focus on three main concepts toward explaining OM turnover at the landscape scale: the landscape spatiotemporal context, OM turnover described by priming and ecological stoichiometry, and anthropogenic effects as a disruptor of natural OM transfer magnitudes and pathways. A conceptual framework is introduced that allows for discussing the disparities in spatial and temporal scales of OM transfer, changes in environmental conditions, ecosystem connectivity, and microbial-substrate interactions. The potential relevance of priming effects in both terrestrial and aquatic systems is addressed. For terrestrial systems, we hypothesize that the interplay between the influx of OM, its corresponding elemental composition, and the elemental demand of the microbial communities may alleviate spatial and metabolic thresholds. In comparison, substrate level OM dynamics may be substantially different in aquatic systems due to matrix effects that accentuate the role of abiotic conditions, substrate quality, and microbial community dynamics. We highlight the disproportionate impact anthropogenic activities can have on OM cycling across the landscape. This includes reversing natural OM flows through the landscape, disrupting ecosystem connectivity, and nutrient additions that cascade across the landscape. This knowledge is crucial for a better understanding of OM cycling in a landscape context, in particular since terrestrial and aquatic compartments may respond differently to the ongoing changes in climate, land use, and other anthropogenic interferences.}, language = {en} } @article{KettnerOberbeckmannLabrenzetal.2019, author = {Kettner, Marie Therese and Oberbeckmann, Sonja and Labrenz, Matthias and Grossart, Hans-Peter}, title = {The Eukaryotic Life on Microplastics in Brackish Ecosystems}, series = {Frontiers in Microbiology}, volume = {10}, journal = {Frontiers in Microbiology}, publisher = {Frontiers Media}, address = {Lausanne}, issn = {1664-302X}, doi = {10.3389/fmicb.2019.00538}, pages = {13}, year = {2019}, abstract = {Microplastics (MP) constitute a widespread contaminant all over the globe. Rivers and wastewater treatment plants (WWTP) transport annually several million tons of MP into freshwaters, estuaries and oceans, where they provide increasing artificial surfaces for microbial colonization. As knowledge on MP-attached communities is insufficient for brackish ecosystems, we conducted exposure experiments in the coastal Baltic Sea, an in-flowing river and a WWTP within the drainage basin. While reporting on prokaryotic and fungal communities from the same set-up previously, we focus here on the entire eukaryotic communities. Using high-throughput 18S rRNA gene sequencing, we analyzed the eukaryotes colonizing on two types of MP, polyethylene and polystyrene, and compared them to the ones in the surrounding water and on a natural surface (wood). More than 500 different taxa across almost all kingdoms of the eukaryotic tree of life were identified on MP, dominated by Alveolata, Metazoa, and Chloroplastida. The eukaryotic community composition on MP was significantly distinct from wood and the surrounding water, with overall lower diversity and the potentially harmful dinoflagellate Pfiesteria being enriched on MP. Co-occurrence networks, which include prokaryotic and eukaryotic taxa, hint at possibilities for dynamic microbial interactions on MP. This first report on total eukaryotic communities on MP in brackish environments highlights the complexity of MP-associated biofilms, potentially leading to altered microbial activities and hence changes in ecosystem functions.}, language = {en} } @misc{KettnerOberbeckmannLabrenzetal.2019, author = {Kettner, Marie Therese and Oberbeckmann, Sonja and Labrenz, Matthias and Grossart, Hans-Peter}, title = {The Eukaryotic Life on Microplastics in Brackish Ecosystems}, series = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe}, number = {741}, issn = {1866-8372}, doi = {10.25932/publishup-43499}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-434996}, pages = {10}, year = {2019}, abstract = {Microplastics (MP) constitute a widespread contaminant all over the globe. Rivers and wastewater treatment plants (WWTP) transport annually several million tons of MP into freshwaters, estuaries and oceans, where they provide increasing artificial surfaces for microbial colonization. As knowledge on MP-attached communities is insufficient for brackish ecosystems, we conducted exposure experiments in the coastal Baltic Sea, an in-flowing river and a WWTP within the drainage basin. While reporting on prokaryotic and fungal communities from the same set-up previously, we focus here on the entire eukaryotic communities. Using high-throughput 18S rRNA gene sequencing, we analyzed the eukaryotes colonizing on two types of MP, polyethylene and polystyrene, and compared them to the ones in the surrounding water and on a natural surface (wood). More than 500 different taxa across almost all kingdoms of the eukaryotic tree of life were identified on MP, dominated by Alveolata, Metazoa, and Chloroplastida. The eukaryotic community composition on MP was significantly distinct from wood and the surrounding water, with overall lower diversity and the potentially harmful dinoflagellate Pfiesteria being enriched on MP. Co-occurrence networks, which include prokaryotic and eukaryotic taxa, hint at possibilities for dynamic microbial interactions on MP. This first report on total eukaryotic communities on MP in brackish environments highlights the complexity of MP-associated biofilms, potentially leading to altered microbial activities and hence changes in ecosystem functions.}, language = {en} } @article{KolmakovaGladyshevFonvielleetal.2019, author = {Kolmakova, Olesya V. and Gladyshev, Michail I. and Fonvielle, Jeremy Andre and Ganzert, Lars and Hornick, Thomas and Grossart, Hans-Peter}, title = {Effects of zooplankton carcasses degradation on freshwater bacterial community composition and implications for carbon cycling}, series = {Environmental microbiology}, volume = {21}, journal = {Environmental microbiology}, number = {1}, publisher = {Wiley}, address = {Hoboken}, issn = {1462-2912}, doi = {10.1111/1462-2920.14418}, pages = {34 -- 49}, year = {2019}, abstract = {Non-predatory mortality of zooplankton provides an abundant, yet, little studied source of high quality labile organic matter (LOM) in aquatic ecosystems. Using laboratory microcosms, we followed the decomposition of organic carbon of fresh C-13-labelled Daphnia carcasses by natural bacterioplankton. The experimental setup comprised blank microcosms, that is, artificial lake water without any organic matter additions (B), and microcosms either amended with natural humic matter (H), fresh Daphnia carcasses (D) or both, that is, humic matter and Daphnia carcasses (HD). Most of the carcass carbon was consumed and respired by the bacterial community within 15 days of incubation. A shift in the bacterial community composition shaped by labile carcass carbon and by humic matter was observed. Nevertheless, we did not observe a quantitative change in humic matter degradation by heterotrophic bacteria in the presence of LOM derived from carcasses. However, carcasses were the main factor driving the bacterial community composition suggesting that the presence of large quantities of dead zooplankton might affect the carbon cycling in aquatic ecosystems. Our results imply that organic matter derived from zooplankton carcasses is efficiently remineralized by a highly specific bacterial community, but does not interfere with the bacterial turnover of more refractory humic matter.}, language = {en} } @article{LundgreenJaspersTravingetal.2019, author = {Lundgreen, Regitze B. C. and Jaspers, Cornelia and Traving, Sachia J. and Ayala, Daniel J. and Lombard, Fabien and Grossart, Hans-Peter and Nielsen, Torkel G. and Munk, Peter and Riemann, Lasse}, title = {Eukaryotic and cyanobacterial communities associated with marine snow particles in the oligotrophic Sargasso Sea}, series = {Scientific reports}, volume = {9}, journal = {Scientific reports}, publisher = {Nature Publ. Group}, address = {London}, issn = {2045-2322}, doi = {10.1038/s41598-019-45146-7}, pages = {12}, year = {2019}, abstract = {Marine snow aggregates represent heterogeneous agglomerates of dead and living organic matter. Composition is decisive for their sinking rates, and thereby for carbon flux to the deep sea. For oligotrophic oceans, information on aggregate composition is particularly sparse. To address this, the taxonomic composition of aggregates collected from the subtropical and oligotrophic Sargasso Sea (Atlantic Ocean) was characterized by 16S and 18S rRNA gene sequencing. Taxonomy assignment was aided by a collection of the contemporary plankton community consisting of 75 morphologically and genetically identified plankton specimens. The diverse rRNA gene reads of marine snow aggregates, not considering Trichodesmium puffs, were dominated by copepods (52\%), cnidarians (21\%), radiolarians (11\%), and alveolates (8\%), with sporadic contributions by cyanobacteria, suggesting a different aggregate composition than in eutrophic regions. Composition linked significantly with sampling location but not to any measured environmental parameters or plankton biomass composition. Nevertheless, indicator and network analyses identified key roles of a few rare taxa. This points to complex regulation of aggregate composition, conceivably affected by the environment and plankton characteristics. The extent to which this has implications for particle densities, and consequently for sinking rates and carbon sequestration in oligotrophic waters, needs further interrogation.}, language = {en} } @article{MasigolKhodaparastWoodhouseetal.2019, author = {Masigol, Hossein and Khodaparast, Seyed Akbar and Woodhouse, Jason Nicholas and Rojas Jim{\´e}nez, Keilor and Fonvielle, Jeremy Andre and Rezakhani, Forough and Mostowfizadeh-Ghalamfarsa, Reza and Neubauer, Darshan and Goldhammer, Tobias and Grossart, Hans-Peter}, title = {The contrasting roles of aquatic fungi and oomycetes in the degradation and transformation of polymeric organic matter}, series = {Limnology and oceanography}, volume = {64}, journal = {Limnology and oceanography}, number = {6}, publisher = {Wiley}, address = {Hoboken}, issn = {0024-3590}, pages = {2662 -- 2678}, year = {2019}, abstract = {Studies on the ecological role of fungi and, to a lesser extent, oomycetes, are receiving increasing attention, mainly due to their participation in the cycling of organic matter in aquatic ecosystems. To unravel their importance in humification processes, we isolated several strains of fungi and oomycetes from Anzali lagoon, Iran. We then performed taxonomic characterization by morphological and molecular methods, analyzed the ability to degrade several polymeric substrates, performed metabolic fingerprinting with Ecoplates, and determined the degradation of humic substances (HS) using liquid chromatography-organic carbon detection. Our analyses highlighted the capacity of aquatic fungi to better degrade a plethora of organic molecules, including complex polymers. Specifically, we were able to demonstrate not only the utilization of these complex polymers, but also the role of fungi in the production of HS. In contrast, oomycetes, despite some morphological and physiological similarities with aquatic fungi, exhibited a propensity toward opportunism, quickly benefitting from the availability of small organic molecules, while exhibiting sensitivity toward more complex polymers. Despite their contrasting roles, our study highlights the importance of both oomycetes and fungi in aquatic organic matter transformation and cycling with potential implications for the global carbon cycle.}, language = {en} } @misc{NumbergerDreierVullioudetal.2019, author = {Numberger, Daniela and Dreier, Carola and Vullioud, Colin and Gabriel, Guelsah and Greenwood, Alex D. and Grossart, Hans-Peter}, title = {Correction: Recovery of influenza A viruses from lake water and sediments by experimental inoculation (vol 14, e0216880, 2019)}, series = {PLoS one}, volume = {14}, journal = {PLoS one}, number = {6}, publisher = {PLoS}, address = {San Fransisco}, issn = {1932-6203}, doi = {10.1371/journal.pone.0218882}, pages = {1}, year = {2019}, language = {en} } @article{NumbergerDreierVullioudetal.2019, author = {Numberger, Daniela and Dreier, Carole and Vullioud, Colin and Gabriel, G{\"u}lsah and Greenwood, Alex D. and Grossart, Hans-Peter}, title = {Recovery of influenza a viruses from lake water and sediments by experimental inoculation}, series = {PLoS one}, volume = {14}, journal = {PLoS one}, number = {5}, publisher = {PLoS}, address = {San Fransisco}, issn = {1932-6203}, doi = {10.1371/journal.pone.0216880}, pages = {13}, year = {2019}, abstract = {Influenza A viruses (IAV) are zoonotic pathogens relevant to human, domestic animal and wildlife health. Many avian IAVs are transmitted among waterfowl via a faecal-oral-route. Therefore, environmental water where waterfowl congregate may play an important role in the ecology and epidemiology of avian IAV. Water and sediment may sustain and transmit virus among individuals or species. It is unclear at what concentrations waterborne viruses are infectious or remain detectable. To address this, we performed lake water and sediment dilution experiments with varying concentrations or infectious doses of four IAV strains from seal, turkey, duck and gull. To test for infectivity of the IAV strains in a concentration dependent manner, we applied cultivation to specific pathogen free (SPF) embryonated chicken eggs and Madin-Darby Canine Kidney (MDCK) cells. IAV recovery was more effective from embryonated chicken eggs than MDCK cells for freshwater lake dilutions, whereas, MDCK cells were more effective for viral recovery from sediment samples. Low infectious dose (1 PFU/200 mu L) was sufficient in most cases to detect and recover IAV from lake water dilutions. Sediment required higher initial infectious doses (>= 100 PFU/200 mu L).}, language = {en} } @article{NumbergerGanzertZoccaratoetal.2019, author = {Numberger, Daniela and Ganzert, Lars and Zoccarato, Luca and M{\"u}hldorfer, Kristin and Sauer, Sascha and Grossart, Hans-Peter and Greenwood, Alex D.}, title = {Characterization of bacterial communities in wastewater with enhanced taxonomic resolution by full-length 16S rRNA sequencing}, series = {Scientific reports}, volume = {9}, journal = {Scientific reports}, publisher = {Nature Publ. Group}, address = {London}, issn = {2045-2322}, doi = {10.1038/s41598-019-46015-z}, pages = {14}, year = {2019}, abstract = {Wastewater treatment is crucial to environmental hygiene in urban environments. However, wastewater treatment plants (WWTPs) collect chemicals, organic matter, and microorganisms including pathogens and multi-resistant bacteria from various sources which may be potentially released into the environment via WWTP effluent. To better understand microbial dynamics in WWTPs, we characterized and compared the bacterial community of the inflow and effluent of a WWTP in Berlin, Germany using full-length 16S rRNA gene sequences, which allowed for species level determination in many cases and generally resolved bacterial taxa. Significantly distinct bacterial communities were identified in the wastewater inflow and effluent samples. Dominant operational taxonomic units (OTUs) varied both temporally and spatially. Disease associated bacterial groups were efficiently reduced in their relative abundance from the effluent by the WWTP treatment process, except for Legionella and Leptospira species which demonstrated an increase in relative proportion from inflow to effluent. This indicates that WWTPs, while effective against enteric bacteria, may enrich and release other potentially pathogenic bacteria into the environment. The taxonomic resolution of full-length 16S rRNA genes allows for improved characterization of potential pathogenic taxa and other harmful bacteria which is required to reliably assess health risk.}, language = {en} } @article{NumbergerRiedelMcEwenetal.2019, author = {Numberger, Daniela and Riedel, Thomas and McEwen, Gayle and N{\"u}bel, Ulrich and Frentrup, Martinique and Schober, Isabel and Bunk, Boyke and Spr{\"o}er, Cathrin and Overmann, J{\"o}rg and Grossart, Hans-Peter and Greenwood, Alex D.}, title = {Genomic analysis of three Clostridioides difficile isolates from urban water sources}, series = {Anaerobe}, volume = {56}, journal = {Anaerobe}, publisher = {Elsevier}, address = {Oxford}, issn = {1075-9964}, doi = {10.1016/j.anaerobe.2019.01.002}, pages = {22 -- 26}, year = {2019}, abstract = {We investigated inflow of a wastewater treatment plant and sediment of an urban lake for the presence of Clostridioides difficile by cultivation and PCR. Among seven colonies we sequenced the complete genomes of three: two non-toxigenic isolates from wastewater and one toxigenic isolate from the urban lake. For all obtained isolates, a close genomic relationship with human-derived isolates was observed. (C) 2019 Elsevier Ltd. All rights reserved.}, language = {en} } @article{PerkinsGanzertRojasJimenezetal.2019, author = {Perkins, Anita K. and Ganzert, Lars and Rojas-Jimenez, Keilor and Fonvielle, Jeremy Andre and Hose, Grant C. and Grossart, Hans-Peter}, title = {Highly diverse fungal communities in carbon-rich aquifers of two contrasting lakes in Northeast Germany}, series = {Fungal ecology}, volume = {41}, journal = {Fungal ecology}, publisher = {Elsevier}, address = {Oxford}, issn = {1754-5048}, doi = {10.1016/j.funeco.2019.04.004}, pages = {116 -- 125}, year = {2019}, abstract = {Fungi are an important component of microbial communities and are well known for their ability to decompose refractory, highly polymeric organic matter. In soils and aquatic systems, fungi play an important role in carbon processing, however, their diversity, community structure and function as well as ecological role, particularly in groundwater, are poorly studied. The aim of this study was to examine the fungal community composition, diversity and function in groundwater from 16 boreholes located in the vicinity of two lakes in NE Germany that are characterized by contrasting trophic status. The analysis of 28S rRNA gene sequences amplified from the groundwater revealed high fungal diversity arid clear differences in community structure between the aquifers. Most sequences were assigned to Ascomycota and Basidiomycota, but members of Chytridiomycota, Cryptomycota, Zygomycota, Blastocladiomycota, Glomeromycota and Neocallimastigomycota were also detected. In addition, 27 species of fungi were successfully isolated from the groundwater samples and tested for their ability to decompose complex organic polymers - the predominant carbon source in the groundwater. Most isolates showed positive activities for at least one of the tested polymer types, with three strains, belonging to the genera Gibberella, Isaria and Cadophora, able to decompose all tested substrates. Our results highlight the high diversity of fungi in groundwater, and point to their important ecological role in breaking down highly polymeric organic matter in these isolated microbial habitats. (C) 2019 Elsevier Ltd and British Mycological Society. All rights reserved.}, language = {en} } @article{RojasJimenezRieckWurzbacheretal.2019, author = {Rojas-Jimenez, Keilor and Rieck, Angelika and Wurzbacher, Christian and J{\"u}rgens, Klaus and Labrenz, Matthias and Grossart, Hans-Peter}, title = {A Salinity Threshold Separating Fungal Communities in the Baltic Sea}, series = {Frontiers in Microbiology}, volume = {10}, journal = {Frontiers in Microbiology}, publisher = {Frontiers Media}, address = {Lausanne}, issn = {1664-302X}, doi = {10.3389/fmicb.2019.00680}, pages = {9}, year = {2019}, abstract = {Salinity is a significant factor for structuring microbial communities, but little is known for aquatic fungi, particularly in the pelagic zone of brackish ecosystems. In this study, we explored the diversity and composition of fungal communities following a progressive salinity decline (from 34 to 3 PSU) along three transects of ca. 2000 km in the Baltic Sea, the world's largest estuary. Based on 18S rRNA gene sequence analysis, we detected clear changes in fungal community composition along the salinity gradient and found significant differences in composition of fungal communities established above and below a critical value of 8 PSU. At salinities below this threshold, fungal communities resembled those from freshwater environments, with a greater abundance of Chytridiomycota, particularly of the orders Rhizophydiales, Lobulomycetales, and Gromochytriales. At salinities above 8 PSU, communities were more similar to those from marine environments and, depending on the season, were dominated by a strain of the LKM11 group (Cryptomycota) or by members of Ascomycota and Basidiomycota. Our results highlight salinity as an important environmental driver also for pelagic fungi, and thus should be taken into account to better understand fungal diversity and ecological function in the aquatic realm.}, language = {en} } @misc{RojasJimenezRieckWurzbacheretal.2019, author = {Rojas-Jimenez, Keilor and Rieck, Angelika and Wurzbacher, Christian and J{\"u}rgens, Klaus and Labrenz, Matthias and Grossart, Hans-Peter}, title = {A Salinity Threshold Separating Fungal Communities in the Baltic Sea}, series = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe}, number = {739}, issn = {1866-8372}, doi = {10.25932/publishup-43493}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-434937}, pages = {9}, year = {2019}, abstract = {Salinity is a significant factor for structuring microbial communities, but little is known for aquatic fungi, particularly in the pelagic zone of brackish ecosystems. In this study, we explored the diversity and composition of fungal communities following a progressive salinity decline (from 34 to 3 PSU) along three transects of ca. 2000 km in the Baltic Sea, the world's largest estuary. Based on 18S rRNA gene sequence analysis, we detected clear changes in fungal community composition along the salinity gradient and found significant differences in composition of fungal communities established above and below a critical value of 8 PSU. At salinities below this threshold, fungal communities resembled those from freshwater environments, with a greater abundance of Chytridiomycota, particularly of the orders Rhizophydiales, Lobulomycetales, and Gromochytriales. At salinities above 8 PSU, communities were more similar to those from marine environments and, depending on the season, were dominated by a strain of the LKM11 group (Cryptomycota) or by members of Ascomycota and Basidiomycota. Our results highlight salinity as an important environmental driver also for pelagic fungi, and thus should be taken into account to better understand fungal diversity and ecological function in the aquatic realm.}, language = {en} } @article{SchornSalmanCarvalhoLittmannetal.2019, author = {Schorn, Sina and Salman-Carvalho, Verena and Littmann, Sten and Ionescu, Danny and Grossart, Hans-Peter and Cypionka, Heribert}, title = {Cell architecture of the giant sulfur bacterium achromatium oxaliferum}, series = {FEMS Microbiology Ecology}, volume = {96}, journal = {FEMS Microbiology Ecology}, number = {2}, publisher = {Oxford University Press}, address = {Oxford}, issn = {1574-6941}, doi = {10.1093/femsec/fiz200}, pages = {1 -- 8}, year = {2019}, abstract = {Achromatium oxaliferum is a large sulfur bacterium easily recognized by large intracellular calcium carbonate bodies. Although these bodies often fill major parts of the cells' volume, their role and specific intracellular location are unclear. In this study, we used various microscopy and staining techniques to identify the cell compartment harboring the calcium carbonate bodies. We observed that Achromatium cells often lost their calcium carbonate bodies, either naturally or induced by treatments with diluted acids, ethanol, sodium bicarbonate and UV radiation which did not visibly affect the overall shape and motility of the cells (except for UV radiation). The water-soluble fluorescent dye fluorescein easily diffused into empty cavities remaining after calcium carbonate loss. Membranes (stained with Nile Red) formed a network stretching throughout the cell and surrounding empty or filled calcium carbonate cavities. The cytoplasm (stained with FITC and SYBR Green for nucleic acids) appeared highly condensed and showed spots of dissolved Ca2+ (stained with Fura-2). From our observations, we conclude that the calcium carbonate bodies are located in the periplasm, in extra-cytoplasmic pockets of the cytoplasmic membrane and are thus kept separate from the cell's cytoplasm. This periplasmic localization of the carbonate bodies might explain their dynamic formation and release upon environmental changes.}, language = {en} } @misc{SchornSalmanCarvalhoLittmannetal.2019, author = {Schorn, Sina and Salman-Carvalho, Verena and Littmann, Sten and Ionescu, Danny and Grossart, Hans-Peter and Cypionka, Heribert}, title = {Cell architecture of the giant sulfur bacterium achromatium oxaliferum}, series = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {2}, issn = {1866-8372}, doi = {10.25932/publishup-54993}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-549935}, pages = {10}, year = {2019}, abstract = {Achromatium oxaliferum is a large sulfur bacterium easily recognized by large intracellular calcium carbonate bodies. Although these bodies often fill major parts of the cells' volume, their role and specific intracellular location are unclear. In this study, we used various microscopy and staining techniques to identify the cell compartment harboring the calcium carbonate bodies. We observed that Achromatium cells often lost their calcium carbonate bodies, either naturally or induced by treatments with diluted acids, ethanol, sodium bicarbonate and UV radiation which did not visibly affect the overall shape and motility of the cells (except for UV radiation). The water-soluble fluorescent dye fluorescein easily diffused into empty cavities remaining after calcium carbonate loss. Membranes (stained with Nile Red) formed a network stretching throughout the cell and surrounding empty or filled calcium carbonate cavities. The cytoplasm (stained with FITC and SYBR Green for nucleic acids) appeared highly condensed and showed spots of dissolved Ca2+ (stained with Fura-2). From our observations, we conclude that the calcium carbonate bodies are located in the periplasm, in extra-cytoplasmic pockets of the cytoplasmic membrane and are thus kept separate from the cell's cytoplasm. This periplasmic localization of the carbonate bodies might explain their dynamic formation and release upon environmental changes.}, language = {en} } @article{StegerKimGanzertetal.2019, author = {Steger, Kristin and Kim, Amy Taeyen and Ganzert, Lars and Grossart, Hans-Peter and Smart, David R.}, title = {Floodplain soil and its bacterial composition are strongly affected by depth}, series = {FEMS microbiology ecology}, volume = {95}, journal = {FEMS microbiology ecology}, number = {3}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0168-6496}, doi = {10.1093/femsec/fiz014}, pages = {11}, year = {2019}, abstract = {We studied bacterial abundance and community structure of five soil cores using high-throughput sequencing of the 16S rRNA gene. Shifts in the soil bacterial composition were more pronounced within a vertical profile than across the landscape. Soil organic carbon (SOC) and nitrogen (N) concentrations decreased exponentially with soil depth and revealed a buried carbon-rich horizon between 0.8 and 1.3 m across all soil cores. This buried horizon was phylogenetically similar to its surrounding subsoils supporting the idea that the type of carbon, not necessarily the amount of carbon was driving the apparent similarities. In contrast to other studies, Nitrospirae was one of our major phyla with relatively high abundances throughout the soil profile except for the surface soil. Although depth is the major driver shaping soil bacterial community structure, positive correlations with SOC and N concentrations, however, were revealed with the bacterial abundance of Acidobacteria, one of the major, and Gemmatimonadetes, one of the minor phyla in our study. Our study showed that bacterial diversity in soils below 2.0 m can be still as high if not higher than in the above laying subsurface soil suggesting that various bacteria throughout the soil profile influence major biogeochemical processes in floodplain soils.}, language = {en} } @article{TangBackhausRiemannetal.2019, author = {Tang, Kam W. and Backhaus, Liv and Riemann, Lasse and Koski, Marja and Grossart, Hans-Peter and Munk, Peter and Nielsen, Torkel Gissel}, title = {Copepod carcasses in the subtropical convergence zone of the Sargasso Sea}, series = {Journal of plankton research}, volume = {41}, journal = {Journal of plankton research}, number = {4}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0142-7873}, doi = {10.1093/plankt/fbz038}, pages = {549 -- 560}, year = {2019}, abstract = {The oligotrophic subtropical gyre covers a vast area of the Atlantic Ocean. Decades of time-series monitoring have generated detailed temporal information about zooplankton species and abundances at fixed locations within the gyre, but their live/dead status is often omitted, especially in the dynamic subtropical convergence zone (STCZ) where the water column stratification pattern can change considerably across the front as warm and cold water masses converge. We conducted a detailed survey in the North Atlantic STCZ and showed that over 85\% of the copepods were typically concentrated in the upper 200 m. Copepod carcasses were present in all samples and their proportional numerical abundances increased with depth, reaching up to 91\% at 300-400 m. Overall, 14-19\% of the copepods within the upper 200 m were carcasses. Shipboard experiments showed that during carcass decomposition, microbial respiration increased, and the bacterial community associated with the carcasses diverged from that in the ambient water. Combining field and experimental data, we estimated that decomposing copepod carcasses constitute a negligible oxygen sink in the STCZ, but sinking carcasses may represent an overlooked portion of the passive carbon sinking flux and should be incorporated in future studies of carbon flux in this area.}, language = {en} } @article{TiegsCostelloIskenetal.2019, author = {Tiegs, Scott D. and Costello, David M. and Isken, Mark W. and Woodward, Guy and McIntyre, Peter B. and Gessner, Mark O. and Chauvet, Eric and Griffiths, Natalie A. and Flecker, Alex S. and Acuna, Vicenc and Albarino, Ricardo and Allen, Daniel C. and Alonso, Cecilia and Andino, Patricio and Arango, Clay and Aroviita, Jukka and Barbosa, Marcus V. M. and Barmuta, Leon A. and Baxter, Colden V. and Bell, Thomas D. C. and Bellinger, Brent and Boyero, Luz and Brown, Lee E. and Bruder, Andreas and Bruesewitz, Denise A. and Burdon, Francis J. and Callisto, Marcos and Canhoto, Cristina and Capps, Krista A. and Castillo, Maria M. and Clapcott, Joanne and Colas, Fanny and Colon-Gaud, Checo and Cornut, Julien and Crespo-Perez, Veronica and Cross, Wyatt F. and Culp, Joseph M. and Danger, Michael and Dangles, Olivier and de Eyto, Elvira and Derry, Alison M. and Diaz Villanueva, Veronica and Douglas, Michael M. and Elosegi, Arturo and Encalada, Andrea C. and Entrekin, Sally and Espinosa, Rodrigo and Ethaiya, Diana and Ferreira, Veronica and Ferriol, Carmen and Flanagan, Kyla M. and Fleituch, Tadeusz and Shah, Jennifer J. Follstad and Frainer, Andre and Friberg, Nikolai and Frost, Paul C. and Garcia, Erica A. and Lago, Liliana Garcia and Garcia Soto, Pavel Ernesto and Ghate, Sudeep and Giling, Darren P. and Gilmer, Alan and Goncalves, Jose Francisco and Gonzales, Rosario Karina and Graca, Manuel A. S. and Grace, Mike and Grossart, Hans-Peter and Guerold, Francois and Gulis, Vlad and Hepp, Luiz U. and Higgins, Scott and Hishi, Takuo and Huddart, Joseph and Hudson, John and Imberger, Samantha and Iniguez-Armijos, Carlos and Iwata, Tomoya and Janetski, David J. and Jennings, Eleanor and Kirkwood, Andrea E. and Koning, Aaron A. and Kosten, Sarian and Kuehn, Kevin A. and Laudon, Hjalmar and Leavitt, Peter R. and Lemes da Silva, Aurea L. and Leroux, Shawn J. and Leroy, Carri J. and Lisi, Peter J. and MacKenzie, Richard and Marcarelli, Amy M. and Masese, Frank O. and Mckie, Brendan G. and Oliveira Medeiros, Adriana and Meissner, Kristian and Milisa, Marko and Mishra, Shailendra and Miyake, Yo and Moerke, Ashley and Mombrikotb, Shorok and Mooney, Rob and Moulton, Tim and Muotka, Timo and Negishi, Junjiro N. and Neres-Lima, Vinicius and Nieminen, Mika L. and Nimptsch, Jorge and Ondruch, Jakub and Paavola, Riku and Pardo, Isabel and Patrick, Christopher J. and Peeters, Edwin T. H. M. and Pozo, Jesus and Pringle, Catherine and Prussian, Aaron and Quenta, Estefania and Quesada, Antonio and Reid, Brian and Richardson, John S. and Rigosi, Anna and Rincon, Jose and Risnoveanu, Geta and Robinson, Christopher T. and Rodriguez-Gallego, Lorena and Royer, Todd V. and Rusak, James A. and Santamans, Anna C. and Selmeczy, Geza B. and Simiyu, Gelas and Skuja, Agnija and Smykla, Jerzy and Sridhar, Kandikere R. and Sponseller, Ryan and Stoler, Aaron and Swan, Christopher M. and Szlag, David and Teixeira-de Mello, Franco and Tonkin, Jonathan D. and Uusheimo, Sari and Veach, Allison M. and Vilbaste, Sirje and Vought, Lena B. M. and Wang, Chiao-Ping and Webster, Jackson R. and Wilson, Paul B. and Woelfl, Stefan and Xenopoulos, Marguerite A. and Yates, Adam G. and Yoshimura, Chihiro and Yule, Catherine M. and Zhang, Yixin X. and Zwart, Jacob A.}, title = {Global patterns and drivers of ecosystem functioning in rivers and riparian zones}, series = {Science Advances}, volume = {5}, journal = {Science Advances}, number = {1}, publisher = {American Assoc. for the Advancement of Science}, address = {Washington}, issn = {2375-2548}, doi = {10.1126/sciadv.aav0486}, pages = {8}, year = {2019}, abstract = {River ecosystems receive and process vast quantities of terrestrial organic carbon, the fate of which depends strongly on microbial activity. Variation in and controls of processing rates, however, are poorly characterized at the global scale. In response, we used a peer-sourced research network and a highly standardized carbon processing assay to conduct a global-scale field experiment in greater than 1000 river and riparian sites. We found that Earth's biomes have distinct carbon processing signatures. Slow processing is evident across latitudes, whereas rapid rates are restricted to lower latitudes. Both the mean rate and variability decline with latitude, suggesting temperature constraints toward the poles and greater roles for other environmental drivers (e.g., nutrient loading) toward the equator. These results and data set the stage for unprecedented "next-generation biomonitoring" by establishing baselines to help quantify environmental impacts to the functioning of ecosystems at a global scale.}, language = {en} }