title: Characterization of triclosan metabolism in Sphingomonas sp. strain YL-JM2C.
abstract: Triclosan (TCS) is one of the most widespread emerging contaminants and has adverse impact on aquatic ecosystem, yet little is known about its complete biodegradation mechanism in bacteria. Sphingomonas sp, strain YL-JM2C, isolated from activated sludge of a wastewater treatment plant, was very effective on degrading TCS. Response surface methodology (RSM) was applied to optimize the conditions like temperature and pH. From RSM, the optimal TCS degradation conditions were found to be 30 °C and pH 7.0. Under optimal conditions, strain YL-JM2C completely mineralized TCS (5 mg L(-1)) within 72 h. Gas chromatography-mass spectrometry analysis revealed that 2,4-dichlorophenol, 2-chlorohydroquinone and hydroquinone are three main by-products of TCS. Furthermore, stable isotope experimental results revealed that the (13)C12-TCS was completely mineralized into CO2 and part of heavier carbon ((13)C) of labeled TCS was utilized by strain YL-JM2C to synthesize fatty acids (PLFAs). Cell surface hydrophobicity (CSH) and degradation test results suggested that the strain could enhance degradation capacity of TCS through increasing CSH. In addition, the bacterium also completely degraded spiked TCS (5 mg L(-1)) in wastewater collected from the wastewater treatment plant. Hence, these results suggest that the strain has potential to remediate TCS in the environment.
authors.affiliation: Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021 China.
authors.forename: Sikandar I
authors.initials: SI
authors.lastname: Mulla
authors.affiliation: College of Ecology and Resource Engineering, Wuyi University, Wuyishan City 354300, China.
authors.forename: Han
authors.initials: H
authors.lastname: Wang
authors.affiliation: Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021 China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Sun
authors.affiliation: Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021 China.
authors.forename: Anyi
authors.initials: A
authors.lastname: Hu
authors.affiliation: Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021 China.
authors.forename: Chang-Ping
authors.initials: CP
authors.lastname: Yu
mesh_terms: D002247:Carbon Isotopes / Q000737:chemistry; D002733:Chlorophenols / Q000032:analysis; D005227:Fatty Acids / Q000096:biosynthesis; D008401:Gas Chromatography-Mass Spectrometry; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D006873:Hydroquinones / Q000032:analysis; D007553:Isotope Labeling; D010088:Oxidoreductases / Q000378:metabolism; D010802:Phylogeny; D020578:Sphingomonas / Q000145:classification / Q000254:growth & development / Q000378:metabolism*; D013696:Temperature; D014260:Triclosan / Q000032:analysis / Q000378:metabolism*
chemical_list: D002247:Carbon Isotopes; D002733:Chlorophenols; D005227:Fatty Acids; D006873:Hydroquinones; D014260:Triclosan; D010088:Oxidoreductases; C023314:hydroquinone dehydrogenases; C004762:2,4-dichlorophenol; C031927:hydroquinone