Biodegradation of Quinoline by a Newly Isolated Salt-Tolerating Bacterium Rhodococcus gordoniae Strain JH145

• DOI: 10.3390/microorganisms10040797
• Publication Date: 2022-04-10T10:02:54Z
• Authors: Yinhu Jiang; Fuyin Zhang; Siqiong Xu; Pan Yang; Xiao Wang; Xuan Zhang; Qing Hong; Jiguo Qiu; Cuiwei Chu; Jian He
• Keywords: new degradation pathway; QH301-705.5; JH145; quinoline; biodegradation; salt-tolerance; <i>Rhodococcus</i>; JH145; new degradation pathway; biodegradation; 01 natural sciences; Article; 6. Clean water; quinoline; salt-tolerance; Biology (General); <i>Rhodococcus</i>; 0105 earth and related environmental sciences

Quinoline is a typical nitrogen-heterocyclic compound with high toxicity and carcinogenicity which exists ubiquitously in industrial wastewater. In this study, a new quinoline-degrading bacterial strain Rhodococcus sp. JH145 was isolated from oil-contaminated soil. Strain JH145 could grow with quinoline as the sole carbon source. The optimum growth temperature, pH, and salt concentration were 30 °C, 8.0, and 1%, respectively. 100 mg/L quinoline could be completely removed within 28 h. Particularly, strain JH145 showed excellent quinoline biodegradation ability under a high-salt concentration of 7.5%. Two different quinoline degradation pathways, a typical 8-hydroxycoumarin pathway, and a unique anthranilate pathway were proposed based on the intermediates identified by liquid chromatography–time of flight mass spectrometry. Our present results provided new candidates for industrial application in quinoline-contaminated wastewater treatment even under high-salt conditions.