Scientific Reports Sci Rep 2045-2322 12 2019 9 1 Characterization of bacterial communities in wastewater with enhanced taxonomic resolution by full-length 16S rRNA sequencing Daniela Numberger Lars Ganzert http://orcid.org/0000-0001-9595-1041 Luca Zoccarato Kristin Mühldorfer Sascha Sauer Hans-Peter Grossart http://orcid.org/0000-0002-9141-0325 Alex D. Greenwood 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.

07 04 2019 9673 46015 1 10.1007/springer_crossmark_policy link.springer.com false 8 February 2019 21 June 2019 4 July 2019 The authors declare no competing interests. Leibniz-Gemeinschaft https://doi.org/10.13039/501100001664 SAS-2015-FZB-LFV https://creativecommons.org/licenses/by/4.0 https://creativecommons.org/licenses/by/4.0 10.1038/s41598-019-46015-z 20221217115512161 https://www.nature.com/articles/s41598-019-46015-z https://www.nature.com/articles/s41598-019-46015-z.pdf https://www.nature.com/articles/s41598-019-46015-z.pdf https://www.nature.com/articles/s41598-019-46015-z Sci. Total Environ. B D’Arcy 265 359 2001 10.1016/S0048-9697(00)00676-8 D’Arcy, B. & Frost, A. The role of best management practices in alleviating water quality problems associated with diffuse pollution. Sci. Total Environ. 265, 359–367 (2001). Int. Microbiol. Off. J. Span. Soc. Microbiol SL McLellan 18 141 2015 McLellan, S. L., Fisher, J. C. & Newton, R. J. The microbiome of urban waters. Int. Microbiol. 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