Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark.
Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
Appl Environ Microbiol. 2020 Apr 17;86(9). doi: 10.1128/AEM.03044-19.
Pathogenic bacteria in wastewater are generally considered to be efficiently removed in biological wastewater treatment plants. This understanding is almost solely based on culture-based control measures, and here we show, by applying culture-independent methods, that the removal of species in the genus was less effective than for many other abundant genera in the influent wastewater. was one of the most abundant genera in influent wastewater at 14 municipal wastewater treatment plants and was also abundant in the "clean" effluent from all the plants, reaching up to 30% of all bacteria as analyzed by 16S rRNA gene amplicon sequencing. Metagenomic analyses, culturing, genome sequencing of isolates, and visualization by fluorescent hybridization (FISH) confirmed the presence of the human-pathogenic and in both influent and effluent. The main reason for the high relative abundance in the effluent was probably that cells, compared to those of other abundant genera in the influent, did not flocculate and attach well to the activated sludge flocs, leaving a relatively large fraction dispersed in the water phase. The study shows there is an urgent need for new standardized culture-independent measurements of pathogens in effluent wastewaters, e.g., amplicon sequencing, and an investigation of the problem on a global scale to quantify the risk for humans and livestock. The genus was unexpectedly abundant in the effluent from 14 Danish wastewater treatment plants treating municipal wastewater, and the species included the human-pathogenic and Recent studies have shown that is common in wastewater worldwide, so the study indicates that discharge of members of the genus may be a global problem, and further studies are needed to quantify the risk and potentially minimize the discharge. The study also shows that culture-based analyses are insufficient for proper effluent quality control, and new standardized culture-independent measurements of effluent quality encompassing most pathogens should be considered.
废水中的病原细菌通常被认为在生物污水处理厂中能被有效去除。这种理解几乎完全基于基于培养的控制措施，而在这里，我们通过应用非培养方法表明，与许多其他在进水废水中丰富的属相比，属的去除效果较差。在 14 个市政污水处理厂的进水废水中，是最丰富的属之一，在所有这些工厂的“清洁”出水中也很丰富，通过 16S rRNA 基因扩增子测序分析，达到所有细菌的 30%。宏基因组分析、培养、分离株基因组测序以及荧光杂交（FISH）可视化证实了人和病原体在进水和出水中的存在。在出水中相对丰度高的主要原因可能是与进水中其他丰富属的细胞相比，细胞不易絮凝和附着在活性污泥絮体上，使相对较大的一部分分散在水相中。该研究表明，迫切需要对出水中的病原体进行新的标准化非培养测量，例如扩增子测序，并在全球范围内调查该问题，以量化对人类和牲畜的风险。属在处理市政废水的 14 个丹麦污水处理厂的出水中出人意料地丰富，其中包括人病原体和。最近的研究表明，在全球范围内，是废水的常见物种，因此该研究表明，属的成员的排放可能是一个全球性问题，需要进一步研究来量化风险并可能最小化排放。该研究还表明，基于培养的分析不足以进行适当的出水质量控制，应该考虑采用新的标准化非培养出水质量测量方法，涵盖大多数病原体。
