Rughöft Saskia, Jehmlich Nico, Gutierrez Tony, Kleindienst Sara
Microbial Ecology, Center for Applied Geosciences, University of Tübingen, 72076 Tübingen, Germany.
Department of Molecular Systems Biology, Helmholtz Centre for Environmental Research-UFZ GmbH, 04318 Leipzig, Germany.
Microorganisms. 2020 Dec 22;9(1):3. doi: 10.3390/microorganisms9010003.
The application of chemical dispersants during marine oil spills can affect the community composition and activity of marine microorganisms. Several studies have indicated that certain marine hydrocarbon-degrading bacteria, such as spp., can be inhibited by chemical dispersants, resulting in lower abundances and/or reduced biodegradation rates. However, a major knowledge gap exists regarding the mechanisms underlying these physiological effects. Here, we performed comparative proteomics of the Deepwater Horizon isolate sp. TT1 grown under different conditions. Strain TT1 received different carbon sources (pyruvate vs. -hexadecane) with and without added dispersant (Corexit EC9500A). Additional treatments contained crude oil in the form of a water-accommodated fraction (WAF) or chemically-enhanced WAF (CEWAF; with Corexit). For the first time, we identified the proteins associated with alkane metabolism and alginate biosynthesis in strain TT1, report on its potential for aromatic hydrocarbon biodegradation and present a protein-based proposed metabolism of Corexit components as carbon substrates. Our findings revealed that Corexit exposure affects hydrocarbon metabolism, chemotactic motility, biofilm formation, and induces solvent tolerance mechanisms, like efflux pumps, in strain TT1. This study provides novel insights into dispersant impacts on microbial hydrocarbon degraders that should be taken into consideration for future oil spill response actions.
在海洋石油泄漏期间使用化学分散剂会影响海洋微生物的群落组成和活性。多项研究表明，某些海洋烃降解细菌，如 spp.，会受到化学分散剂的抑制，导致丰度降低和/或生物降解率下降。然而，关于这些生理效应背后的机制仍存在重大知识空白。在此，我们对在不同条件下生长的“深水地平线”分离株 sp. TT1 进行了比较蛋白质组学研究。菌株 TT1 接受不同的碳源（丙酮酸与正十六烷），添加或不添加分散剂（Corexit EC9500A）。其他处理包括以水相组分（WAF）或化学增强水相组分（CEWAF；添加 Corexit）形式存在的原油。我们首次鉴定了菌株 TT1 中与烷烃代谢和藻酸盐生物合成相关的蛋白质，报告了其对芳烃生物降解的潜力，并提出了以蛋白质为基础的 Corexit 组分作为碳底物的代谢途径。我们的研究结果表明，暴露于 Corexit 会影响菌株 TT1 的烃代谢、趋化运动、生物膜形成，并诱导溶剂耐受机制，如外排泵。本研究为分散剂对微生物烃降解菌的影响提供了新的见解，未来的溢油应急行动应予以考虑。
