PDF(Pubmed)
Abstract：
Although microbial degradation is a key sink of polycyclic aromatic hydrocarbons (PAH) in surface seawaters, there is a dearth of field-based evidences of regional divergences in biodegradation and the effects of PAHs on site-specific microbial communities. We compared the magnitude of PAH degradation and its impacts in short-term incubations of coastal Mediterranean and the Maritime Antarctica microbiomes with environmentally relevant concentrations of PAHs. Mediterranean bacteria readily degraded the less hydrophobic PAHs, with rates averaging 4.72 ± 0.5 ng L h-1. Metatranscriptomic responses showed significant enrichments of genes associated to horizontal gene transfer, stress response, and PAH degradation, mainly harbored by Alphaproteobacteria. Community composition changed and increased relative abundances of Bacteroidota and Flavobacteriales. In Antarctic waters, there was no degradation of PAH, and minimal metatranscriptome responses were observed. These results provide evidence for factors such as geographic region, community composition, and pre-exposure history to predict PAH biodegradation in seawater.
摘要：
尽管微生物降解是表层海水中多环芳烃（PAH）的关键汇，缺乏基于野外的证据，表明生物降解的区域差异以及PAHs对特定地点微生物群落的影响。我们比较了PAH降解的程度及其在地中海沿岸和南极海洋微生物群的短期孵化中的影响与环境相关的PAHs浓度。地中海细菌容易降解疏水性较低的PAHs，速率平均为4.72±0.5ngLh-1。代谢组学反应显示与水平基因转移相关的基因显着富集，应激反应，和PAH降解，主要由阿尔法变形杆菌包藏。群落组成发生变化，并增加了拟杆菌和黄杆菌的相对丰度。在南极水域，没有PAH的降解，观察到最小的转移组反应。这些结果为地理区域等因素提供了证据，社区组成,和暴露前历史来预测海水中PAH的生物降解。
