Laothamteep Natthariga, Kawano Hibiki, Vejarano Felipe, Suzuki-Minakuchi Chiho, Shintani Masaki, Nojiri Hideaki, Pinyakong Onruthai
Department of Microbiology, Faculty of Science, Chulalongkorn University, 254 Phyathai Road, Pathumwan, Bangkok, 10330, Thailand; Microbial Technology for Marine Pollution Treatment Research Unit, Faculty of Science, Chulalongkorn University, 254 Phyathai Road, Pathumwan, Bangkok, 10330, Thailand; Biotechnology Research Center, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
Biotechnology Research Center, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
Environ Pollut. 2021 May 15;277:116769. doi: 10.1016/j.envpol.2021.116769. Epub 2021 Feb 16.
The present study showed that syntrophic associations in a defined bacterial consortium, named OPK, containing Mycolicibacterium strains PO1 and PO2, Novosphingobium pentaromativorans PY1 and Bacillus subtilis FW1, led to effective pyrene degradation over a wide range of pH values, temperatures and salinities, as well as in the presence of a second polycyclic aromatic hydrocarbon (PAH). Anthracene, phenanthrene or fluorene facilitated complete pyrene degradation within 9 days, while fluoranthene delayed pyrene degradation. Interestingly, fluoranthene degradation was enhanced in the presence of pyrene. Transcriptome analysis confirmed that Mycolicibacterium strains were the key PAH-degraders during the cometabolism of pyrene and fluoranthene. Notably, the transcription of genes encoding pyrene-degrading enzymes were shown to be important for enhanced fluoranthene degradation. NidAB was the major initial oxygenase involved in the degradation of pyrene and fluoranthene mixture. Other functional genes encoding ribosomal proteins, an iron transporter, ABC transporters and stress response proteins were induced in strains PO1 and PO2. Furthermore, an intermediate pyrene-degrading Novosphingobium strain contributed to protocatechuate degradation. The results demonstrated that synergistic interactions among the bacterial members (PO1, PO2 and PY1) of the consortium OPK promoted the simultaneous degradation of two high molecular weight (HMW) PAHs.
本研究表明，在一个名为OPK的特定细菌群落中，包含分枝杆菌属菌株PO1和PO2、新鞘氨醇菌属的多环芳烃降解菌PY1和枯草芽孢杆菌FW1，在广泛的pH值、温度和盐度范围内，以及在存在第二种多环芳烃（PAH）的情况下，营养互养关联导致芘有效降解。蒽、菲或芴促进了芘在9天内完全降解，而荧蒽则延迟了芘的降解。有趣的是，在芘存在的情况下，荧蒽的降解得到增强。转录组分析证实，分枝杆菌属菌株是芘和荧蒽共代谢过程中的关键PAH降解菌。值得注意的是，编码芘降解酶的基因转录对增强荧蒽降解很重要。NidAB是参与芘和荧蒽混合物降解的主要初始加氧酶。在菌株PO1和PO2中诱导了其他编码核糖体蛋白、铁转运蛋白、ABC转运蛋白和应激反应蛋白的功能基因。此外，一种中间芘降解新鞘氨醇菌菌株有助于原儿茶酸降解。结果表明，群落OPK的细菌成员（PO1、PO2和PY1）之间的协同相互作用促进了两种高分子量（HMW）PAHs的同时降解。
