Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, MI, USA.
Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI, USA.
Microb Biotechnol. 2018 Nov;11(6):995-1007. doi: 10.1111/1751-7915.12870. Epub 2017 Oct 27.
In addition to removing organics and other nutrients, the microorganisms in wastewater treatment plants (WWTPs) biotransform many pharmaceuticals present in wastewater. The objective of this study was to examine the relationship between pharmaceutical biotransformation and biodiversity in WWTP bioreactor microbial communities and identify taxa and functional genes that were strongly associated with biotransformation. Dilution-to-extinction of an activated sludge microbial community was performed to establish cultures with a gradient of microbial biodiversity. Batch experiments were performed using the dilution cultures to determine biotransformation extents of several environmentally relevant pharmaceuticals. With this approach, because the communities were all established from the same original community, and using sequencing of the 16S rRNA and metatranscriptome, we identified candidate taxa and genes whose activity and transcript abundances associated with the extent of individual pharmaceutical biotransformation and were lost across the biodiversity gradient. Metabolic genes such as dehydrogenases, amidases and monooxygenases were significantly associated with pharmaceutical biotransformation, and five genera were identified whose activity significantly associated with pharmaceutical biotransformation. Understanding how biotransformation relates to biodiversity will inform the design of biological WWTPs for enhanced removal of chemicals that negatively impact environmental health.
除了去除有机物和其他营养物质外，废水处理厂 (WWTP) 中的微生物还会使废水中存在的许多药物发生生物转化。本研究的目的是研究 WWTP 生物反应器微生物群落中药物生物转化与生物多样性之间的关系，并确定与生物转化强烈相关的分类群和功能基因。通过对活性污泥微生物群落进行稀释至灭绝处理，建立了具有微生物生物多样性梯度的培养物。使用稀释培养物进行批量实验，以确定几种环境相关药物的生物转化程度。通过这种方法，由于群落均由相同的原始群落建立，并且使用 16S rRNA 和宏转录组测序，我们确定了候选分类群和基因，其活性和转录丰度与个别药物生物转化的程度相关，并且在整个生物多样性梯度中丢失。脱氢酶、酰胺酶和单加氧酶等代谢基因与药物生物转化显著相关，确定了五个与药物生物转化显著相关的属。了解生物转化与生物多样性的关系将为设计用于增强去除对环境健康有负面影响的化学物质的生物 WWTP 提供信息。
