一株3,5,6-三氯-2-吡啶酚降解菌Delftia sp.DFT的分离鉴定及降解途径研究  

Isolation,Identification and Degradation Pathway Study of a 3,5,6-trichloro-2-pyridinol Degrading Strain Delftia sp.DFT

作　　者：贾楠 岳彩旭 吕雪茹 王雪婷 丁宁 王圣惠 JIA Nan;YUE Caixu;L Xueru;WANG Xueting;DING Ning;WANG Shenghui(College of Life Sciences,Liaocheng University,Liaocheng 252059,China)

机构地区：[1]聊城大学生命科学学院,山东聊城252059

出　　处：《聊城大学学报（自然科学版）》2024年第2期89-100,共12页Journal of Liaocheng University:Natural Science Edition

基　　金：山东省自然科学基金面上项目(ZR2020MD103);国家自然科学基金青年基金项目(41401288);聊城大学畜牧学学科开放课题(319312101-19);大学生创新创业训练项目(CXCY2022055,CXCY2023335,CXCY2023339)资助。

摘　　要：微生物降解是消除农药残留物3,5,6-三氯-2-吡啶酚(TCP)的有效方法,但其降解机制并不清楚。为探究TCP完整的代谢途径和降解机制。采用富集分离法从农田土壤中分离了一株TCP降解细菌,并分别通过高效液相色谱和液相色谱-质谱(LC-MS)技术检测了菌株的降解性能,并鉴定了其代谢产物。该菌株为Delftia sp.DFT菌,它能在48 h内对50 mg/L的TCP降解率达34.28%,同时也能降解3,5-二氯-2-吡啶醇、6-氯-2-吡啶醇和2-羟基吡啶等其他氯代吡啶类化合物。在降解TCP过程中,共鉴定了12种不同的TCP代谢产物。初步推测水解-氧化脱氯途径、还原脱氯途径、反硝化及烷基化途径可能共同参与了菌株DFT对TCP的降解。据文献调研,这是首次在Delftia sp.菌中发现有四种可能的TCP代谢途径的报道,这为纯培养物中的TCP降解机制研究提供了参考信息。Microbial degradation is an effective method to eliminate 3,5,6-trichloro-2-pyridinol(TCP).However,there is still no detailed information on the mirobial metabolic mechanism of TCP.In order to explore the complete degradation pathway and metabolic mechanism of TCP.A TCP degrading strain was isolated from farmland soil.The degradation ability and the metabolites of TCP was detected by high performance liquid chromatography(HPLC)and liquid chromatography-mass spectrometry(LC-MS),respectively.The TCP degrading strain was identified as Delftia sp.DFT which could degrade 50 mg/L of TCP at a rate of 34.28%within 48 hours.This strain could also degrade other chloropyridine compounds such as 5-dichloro-2-pyridinol,6-chloro-2-pyridinol and 2-hydroxypyridine.Twelve TCP intermediate metabolites were detected in strain DFT and two possible degradation pathways of TCP were proposed on the basis of LC-MS analysis.The hydrolyzation-oxidation dechlorination pathway,the reduction dechlorination pathway,the denitrification pathway and the alkylation pathway might be involved in TCP biodegradation by strain DFT.This is the first report on four different pathways responsible for TCP degradation in the genus Delftia sp.,which provides new information for the study of TCP degradation mechanism in pure culture.

关 键 词：3 5 6-三氯-2-吡啶酚 降解菌 分离鉴定 代尔夫特菌 降解途径 

分 类 号：X172[环境科学与工程—环境科学]