Ha Danh Duc, Nguyen Thi Oanh
Faculty of Engineering-Technology, Dong Thap University, Pham Huu Lau St., Cao Lanh, Dong Thap, Vietnam.
Center for Chemical Analysis, Dong Thap University, Pham Huu Lau St., Cao Lanh, Dong Thap, Vietnam.
Curr Microbiol. 2019 Feb;76(2):248-257. doi: 10.1007/s00284-018-1617-7. Epub 2019 Jan 2.
A chloroaniline-degrading bacterial strain isolated from polluted sediment in the Mekong River was identified as Geobacter sp. KT5. The obtained isolate was found to utilize a wide range of trichloroanilines (TCAs), dichloroanilines (DCAs), monochloroanilines (MACs), and aniline as sources of carbon and energy. It also used Fe(III) as a terminal electron acceptor under anaerobic conditions. Among the chlorinated anilines, KT5 utilized 2,3,4-trichloroaniline (234TCA) with the highest rate (2.48 ± 0.32 µM day). On determining the degradation pathway for chloroanilines (CAs) in Geobacter sp. KT5, it showed that the removal of ortho and para halogen was dominant. Firstly, KT5 ortho-dechlorinated some TCAs to DCAs, and then reductively transformed them into MACs and aniline prior to complete degradation with the iron reduction stoichiometry and release of nitrogen and chlorine. The KT5 augmentation in sediment slurry enhanced the degradation of CAs and aniline; however, the anaerobic degradation rates in slurry were significantly lower compared to those in liquid media.
从湄公河受污染沉积物中分离出的一株氯苯胺降解细菌菌株被鉴定为地杆菌属KT5。研究发现，该分离菌株能够利用多种三氯苯胺（TCAs）、二氯苯胺（DCAs）、一氯苯胺（MACs）和苯胺作为碳源和能源。在厌氧条件下，它还能将Fe(III)用作末端电子受体。在氯代苯胺中，KT5对2,3,4 - 三氯苯胺（234TCA）的利用速率最高（2.48±0.32 μM/天）。在确定地杆菌属KT5中氯苯胺（CAs）的降解途径时发现，邻位和对位卤素的去除占主导。首先，KT5将一些TCAs邻位脱氯生成DCAs，然后将它们还原转化为MACs和苯胺，最终通过铁还原化学计量比完全降解，并释放出氮和氯。在沉积物浆液中添加KT5可增强CAs和苯胺的降解；然而，浆液中的厌氧降解速率明显低于液体培养基中的降解速率。
