title: Isolation, identification and characteristics of an endophytic quinclorac degrading bacterium Bacillus megaterium Q3.
abstract: In this study, we isolated an endophytic quinclorac-degrading bacterium strain Q3 from the root of tobacco grown in quinclorac contaminated soil. Based on morphological characteristics, Biolog identification, and 16S rDNA sequence analysis, we identified strain Q3 as Bacillus megaterium. We investigated the effects of temperature, pH, inoculation size, and initial quinclorac concentration on growth and degrading efficiency of Q3. Under the optimal degrading condition, Q3 could degrade 93% of quinclorac from the initial concentration of 20 mg/L in seven days. We analyzed the degradation products of quinclorac using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The major degradation products by Q3 were different from those of previously identified quinclorac degrading strains, which suggests that Q3 may employ new pathways for quinclorac degradation. Our indoor pot experiments demonstrated that Q3 can effectively alleviate the quinclorac phytotoxicity in tobacco. As the first endophytic microbial that is capable of degrading quinclorac, Q3 can be a good bioremediation bacterium for quinclorac phytotoxicity.
authors.affiliation: Institute of Pesticide Science, Hunan Agricultural University, Changsha, China; College of Plant Protection, Hunan Agricultural University, Changsha, China.
authors.forename: Min
authors.initials: M
authors.lastname: Liu
authors.affiliation: Institute of Pesticide Science, Hunan Agricultural University, Changsha, China; College of Plant Protection, Hunan Agricultural University, Changsha, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Luo
authors.affiliation: College of Plant Protection, Hunan Agricultural University, Changsha, China; School of Computing, Clemson University, Clemson, South Carolina, United States of America.
authors.forename: Yunsheng
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Institute of Pesticide Science, Hunan Agricultural University, Changsha, China.
authors.forename: Aiping
authors.initials: A
authors.lastname: Zeng
authors.affiliation: Institute of Pesticide Science, Hunan Agricultural University, Changsha, China.
authors.forename: Xiaomao
authors.initials: X
authors.lastname: Zhou
authors.affiliation: College of Plant Protection, Hunan Agricultural University, Changsha, China; School of Computing, Clemson University, Clemson, South Carolina, United States of America.
authors.forename: Feng
authors.initials: F
authors.lastname: Luo
authors.affiliation: Hunan academy of agricultural sciences, Changsha, China.
authors.forename: Lianyang
authors.initials: L
authors.lastname: Bai
mesh_terms: D001410:Bacillus megaterium / Q000145:classification / Q000378:metabolism*; D004275:DNA, Ribosomal / Q000235:genetics; D006540:Herbicides / Q000378:metabolism*; D006868:Hydrolysis; D008969:Molecular Sequence Data; D010802:Phylogeny; D011804:Quinolines / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000235:genetics
chemical_list: D004275:DNA, Ribosomal; D006540:Herbicides; D011804:Quinolines; D012336:RNA, Ribosomal, 16S; C489048:quinclorac