Arsenic methylation by a novel ArsM As(III) S-adenosylmethionine methyltransferase that requires only two conserved cysteine residues.
Arsenic methylation by a novel ArsM As(III) S-adenosylmethionine methyltransferase that requires only two conserved cysteine residues.
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通过一种新型 ArsM As(III) S-腺苷甲硫氨酸甲基转移酶进行砷甲基化，该酶仅需要两个保守的半胱氨酸残基。
DOI：
10.1111/mmi.13882
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发表时间：
2018-01
影响因子：
3.6
通讯作者：
Zhao FJ
中科院分区：
文献类型：
--
作者：
Huang K;Xu Y;Packianathan C;Gao F;Chen C;Zhang J;Shen Q;Rosen BP;Zhao FJ
砷的生物甲基化作用是砷地球化学循环的重要组成部分，影响砷在环境中的毒性和迁移性。砷的生物甲基化是由亚砷酸盐（As（III））S-腺苷甲硫氨酸甲基转移酶（ArsM）催化的。到目前为止，所有确定的ArsM直向同源物与As（III）甲基化活动有四个保守的半胱氨酸残基，这被认为是必不可少的As（III）甲基化。在这里，我们分离了一种As（III）-甲基化细菌，芽孢杆菌CX-1，并鉴定了一种编码S-腺苷甲硫氨酸甲基转移酶的基因，称为BlArsM，与其他ArsM的序列相似性较低（≤ 39%）。BlArsM具有六个半胱氨酸残基（Cys 10、Cys 11、Cys 145、Cys 193、Cys 195和Cys 268），其中三个（Cys 10、Cys 145和Cys 195）与大多数ArsM中发现的保守半胱氨酸残基对齐。BlarsM在芽孢杆菌CX-1中组成型表达。BlarsM的异源表达赋予As（III）抗性。纯化的BlArsM甲基化As（III）和甲基砷（MAs（III）），最终产物为二甲基砷（DMAs（V））。当所有六个半胱氨酸被单独改变为丝氨酸残基时，只有C145 S和C195 S衍生物失去了甲基化As（III）和MA（III）的能力。衍生物C10 S/C11 S/C193 S/C268 S仍具有活性。这些结果表明，BlArsM是一种新的作为（III）S-腺苷甲硫氨酸甲基转移酶，只需要两个保守的半胱氨酸残基。提出了一个由BlArsM进行As（III）甲基化的模型。砷的生物甲基化作用是砷地球化学循环的重要组成部分。我们分离了一株亚砷酸盐甲基化细菌，芽孢杆菌CX-1，并鉴定了一种新的亚砷酸盐S-腺苷甲硫氨酸甲基转移酶（BlArsM），它可以催化砷的生物甲基化。与以前报道的ArsM不同，BlArsM只需要两个保守的半胱氨酸残基就可以发挥催化活性。
Arsenic (As) biomethylation is an important component of the As biogeochemical cycle that can influence As toxicity and mobility in the environment. Biomethylation of As is catalyzed by the enzyme arsenite (As(III)) S-adenosylmethionine methyltransferase (ArsM). To date, all identified ArsM orthologs with As(III) methylation activities have four conserved cysteine residues, which are thought to be essential for As(III) methylation. Here, we isolated an As(III)-methylating bacterium, Bacillus sp. CX-1, and identified a gene encoding a S-adenosylmethionine methyltranserase termed BlArsM with low sequence similarities (≤ 39%) to other ArsMs. BlArsM has six cysteine residues (Cys10, Cys11, Cys145, Cys193, Cys195 and Cys268), three of which (Cys10, Cys145 and Cys195) align with conserved cysteine residues found in most ArsMs. BlarsM is constitutively expressed in Bacillus sp. CX-1. Heterologous expression of BlarsM conferred As(III) resistance. Purified BlArsM methylated both As(III) and methylarsenite (MAs(III)), with a final product of dimethylarsenate (DMAs(V)). When all six cysteines were individually altered to serine residues, only C145S and C195S derivatives lost the ability to methylate As(III) and MAs(III). The derivative C10S/C11S/C193S/C268S was still active. These results suggest that BlArsM is a novel As(III) S-adenosylmethionine methyltransferase requiring only two conserved cysteine residues. A model of As(III) methylation by BlArsM is proposed. Arsenic biomethylation is an important component of the arsenic biogeochemical cycle. We isolated an arsenite-methylating bacterium, Bacillus sp. CX-1, and identified a novel arsenite S-adenosylmethionine methyltransferase (BlArsM) that can catalyze arsenic biomethylation. Different from ArsMs reported previously, BlArsM requires only two conserved cysteine residues for its catalytic activity.
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影响因子：
14.9
作者：
Schneidman-Duhovny D;Inbar Y;Nussinov R;Wolfson HJ
通讯作者：
Wolfson HJ
砷污染水稻土中新型细菌介导的高效砷甲基化和挥发
影响因子：
11.4
作者：
Huang K;Chen C;Zhang J;Tang Z;Shen Q;Rosen BP;Zhao FJ
通讯作者：
Zhao FJ
影响因子：
9.4
作者：
Raab, A;Schat, H;Feldmann, J
通讯作者：
Feldmann, J
具有耐热亚砷酸甲基转移酶的基因工程枯草芽孢杆菌用于砷污染的有机废物的生物修复
影响因子：
4.4
作者：
Huang, Ke;Chen, Chuan;Zhao, Fang-Jie
通讯作者：
Zhao, Fang-Jie
DOI：
10.1093/bioinformatics/btq662
发表时间：
2011-02-01
期刊：
Bioinformatics (Oxford, England)
影响因子：
--
作者：
Benkert P;Biasini M;Schwede T
通讯作者：
Schwede T