Laboratory of Environmental Technology, INET, Tsinghua University, Beijing, PR China.
Bioresour Technol. 2010 Oct;101(19):7683-6. doi: 10.1016/j.biortech.2010.05.026.
A quinoline-degrading strain was isolated from activated sludge of the municipal wastewater treatment plant and identified as Pseudomonas putida on the basis of its partial 16S rRNA gene sequence analysis. The characteristics of quinoline degradation were investigated. The experimental results showed that quinoline at the concentration of 500 mg/L could be completely removed within 3h, but could not be mineralized because special pigments were observed in the process of quinoline biodegradation. The N-atom in the quinoline ring was released as NH(3); some metabolic intermediates were identified, including 2-hydroxyquinoline, 2,8-dihydroxyquinoline and 8-hydroxycoumarin. The metabolic pathway of quinoline by P. putida was tentatively proposed, that is, via 8-hydroxycoumarin pathway, namely, the biodegradation was initiated by hydroxylation at position 2 to form 2-oxo-1,2-dihydroquinoline (2-hydroxyquinoline), which was then oxidized to 8-hydroxy-2-oxo-1,2-dihydro-quinoline (2,8-dihydroxyquinoline) and 8-hydroxycoumarin.
从城市污水处理厂的活性污泥中分离到一株能够降解喹啉的菌株，根据其部分 16S rRNA 基因序列分析，鉴定该菌株为恶臭假单胞菌（Pseudomonas putida）。研究了喹啉的降解特性。实验结果表明，在 500mg/L 喹啉浓度下，3h 内可完全去除喹啉，但不能被矿化，因为在喹啉生物降解过程中观察到特殊的色素。喹啉环中的 N 原子作为 NH3 释放；鉴定出一些代谢中间产物，包括 2-羟基喹啉、2,8-二羟基喹啉和 8-羟基香豆素。初步提出了恶臭假单胞菌降解喹啉的代谢途径，即通过 8-羟基香豆素途径，即通过在 2 位羟基化启动生物降解，形成 2-氧-1,2-二氢喹啉（2-羟基喹啉），然后氧化为 8-羟基-2-氧-1,2-二氢喹啉（2,8-二羟基喹啉）和 8-羟基香豆素。
