您好,欢迎访问中国热带农业科学院 机构知识库!

The Two-Component Monooxygenase MeaXY Initiates the Downstream Pathway of Chloroacetanilide Herbicide Catabolism in Sphingomonads

文献类型: 外文期刊

作者: Cheng, Minggen 2 ; Meng, Qiang 1 ; Yang, Youjian 1 ; Chu, Cuiwei 1 ; Chen, Qing 3 ; Li, Yi 4 ; Cheng, Dan; Hong, Qing; 1 ;

作者机构: 1.Nanjing Agr Univ, Coll Life Sci, Key Lab Microbiol Engn Agr Environm, Minist Agr, Nanjing, Jiangsu, Peoples R China

2.Jiangsu Acad Agr Sci, Inst Agrobiotechnol, Prov Key Lab Agrobiol, Nanjing, Jiangsu, Peoples R China

3.Zaozhuang Univ, Coll Life Sci, Zaozhuang, Shandong, Peoples R China

4.Chinese Acad Trop Agr Sci, Environm

关键词: chloroacetanilide herbicides;2-methyl-6-ethylaniline;2;6-diethylaniline;para-hydroxylation;MeaXY;flavoprotein monooxygenase;sphingomonads

期刊名称:APPLIED AND ENVIRONMENTAL MICROBIOLOGY ( 影响因子:4.792; 五年影响因子:5.26 )

ISSN:

年卷期:

页码:

收录情况: SCI

摘要: Due to the extensive use of chloroacetanilide herbicides over the past 60 years, bacteria have evolved catabolic pathways to mineralize these compounds. In the upstream catabolic pathway, chloroacetanilide herbicides are transformed into the two common metabolites 2-methyl-6-ethylaniline (MEA) and 2,6-diethylaniline (DEA) through N-dealkylation and amide hydrolysis. The pathway downstream of MEA is initiated by the hydroxylation of aromatic rings, followed by its conversion to a substrate for ring cleavage after several steps. Most of the key genes in the pathway have been identified. However, the genes involved in the initial hydroxylation step of MEA are still unknown. As a special aniline derivative, MEA cannot be transformed by the aniline dioxygenases that have been characterized. Sphingobium baderi DE-13 can completely degrade MEA and use it as a sole carbon source for growth. In this work, an MEA degradation-deficient mutant of S. baderi DE-13 was isolated. MEA catabolism genes were predicted through comparative genomic analysis. The results of genetic complementation and heterologous expression demonstrated that the products of meaX and meaY are responsible for the initial step of MEA degradation in S. baderi DE-13. MeaXY is a two-component flavoprotein mono-oxygenase system that catalyzes the hydroxylation of MEA and DEA using NADH and Flavin mononucleotide (FMN) as cofactors. Nuclear magnetic resonance (NMR) analysis confirmed that MeaXY hydroxylates MEA and DEA at the para-position. Transcription of meaX was enhanced remarkably upon induction of MEA or DEA in S. baderi DE-13. Additionally, meaX and meaY were highly conserved among other MEA-degrading sphingomonads. This study fills a gap in our knowledge of the biochemical pathway that carries out mineralization of chloroacetanilide herbicides in sphingomonads.

  • 相关文献

[1]植物生长调节剂2,4-D和GA3对微茫藻18A8(Micractinium sp.)生长和油脂积累的影响. 范新照,费小雯,吴小霞,邓晓东. 2013

作者其他论文 更多>>