title: Biodegradation of 2-methylquinoline by Klebsiella pneumoniae TJ-A isolated from acclimated activated sludge.
abstract: Bacterial strain Klebsiella pneumoniae TJ-A, which was capable of utilizing 2-methylquinoline as the sole carbon and energy source, was isolated from acclimated activated sludge under aerobic conditions. Effects of temperature and initial pH on the biodegradation of 2-methylquinoline by Klebsiella pneumoniae TJ-A were investigated. The optimal temperature and initial pH were 30°C and 7.5, respectively. The degradation process was well described by the Haldane model. Then 1, 2, 3, 4-tetrahydro-2-methylquinoline, 4-ethyl-benzenamine and N-butyl-benzenamine were metabolites detected during the degradation of 2-methylquinoline. 2-Methylquinoline was initially hydroxylated at C-4 to form 2-methyl-4-hydroxy-quinoline, and then to form 2-methyl-4-quinolinol as a result of tautomerism. Hydrogenation of heterocyclic ring between the position 2 and 3 produced 2, 3-dihydro-2-methyl-4-quinolinol. The carbon-carbon bond between the position 2 and 3 in the heterocyclic ring cleaved and then formed 2-ethyl-N-ethyl-benzenamine. Tautomerism might result in the formation of N-butyl-benzenamine. The 4-ethyl-benzenamine was produced as a result of losing one ethyl group from N-butyl-benzenamine. The bacterial strain Klebsiella pneumoniae TJ-A was the priority species in the aerobic activated sludge responsible for the degradation of 2-methylquinoline.
authors.affiliation: a State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering , Tongji University , Shanghai , People's Republic of China.
authors.forename: Lin
authors.initials: L
authors.lastname: Wang
authors.forename: Yongmei
authors.initials: Y
authors.lastname: Li
authors.forename: Jingyuan
authors.initials: J
authors.lastname: Duan
mesh_terms: D000332:Aerobiosis; D001673:Biodegradation, Environmental; D006863:Hydrogen-Ion Concentration; D007711:Klebsiella pneumoniae / Q000302:isolation & purification / Q000378:metabolism*; D011798:Quinaldines / Q000378:metabolism*; D012722:Sewage / Q000382:microbiology*; D013696:Temperature
chemical_list: D011798:Quinaldines; D012722:Sewage; C037073:2-methylquinoline