Genes involved in arsenic transformation and resistance associated with different levels of arsenic-contaminated soils.
Genes involved in arsenic transformation and resistance associated with different levels of arsenic-contaminated soils.
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不同砷污染土壤砷转化和抗性相关基因
DOI：
10.1186/1471-2180-9-4
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发表时间：
2009-01-08
期刊：
影响因子：
4.2
通讯作者：
Wang, Gejiao
中科院分区：
文献类型：
--
作者：
Cai, Lin;Liu, Guanghui;Rensing, Christopher;Wang, Gejiao
背景砷被认为是一种有毒的准金属，主要以无机形式[As(III)和As(V)]存在，并且可以通过自然环境中的微生物氧化还原过程进行转化。 As(III)的毒性和迁移性比As(V)大得多，因此微生物砷氧化还原转化对砷的毒性和迁移性有重大影响，从而极大地影响人类健康。本研究的主要目的是调查3种不同砷污染土壤中微生物抗亚砷酸盐菌种的分布和多样性，并进一步研究这些菌种的抗As(III)水平和相关功能基因。结果从3种不同砷污染土壤中共鉴定出58株抗亚砷酸盐细菌。高度亚砷酸盐耐药菌(MIC > 20 mM)仅从高度砷污染场地中分离到，属于不动杆菌属、农杆菌属、节杆菌属、丛毛单胞菌属、红球菌属、寡养单胞菌属和假单胞菌属。鉴定出属于无色杆菌、农杆菌和假单胞菌的五种亚砷酸盐氧化细菌，它们比非亚砷酸盐氧化细菌表现出更高的平均亚砷酸盐抗性水平。使用简并引物进行 PCR，成功从这些菌株中扩增出编码亚砷酸氧化酶的 5aoxB 基因和 51 个亚砷酸转运蛋白基因 [18arsB、12ACR3(1) 和 21ACR3(2)]。 TheaoxB 基因是亚砷酸氧化细菌特有的。同时含有亚砷酸氧化酶基因（aoxB）和亚砷酸转运蛋白基因（ACR3或arsB）的菌株比仅含有亚砷酸转运蛋白基因的菌株表现出更高的平均亚砷酸抗性水平。 ACR3(2)和arsB的水平转移似乎发生在从高砷污染土壤中分离出来的菌株中。结论长期砷污染的土壤可能导致高度多样化的抗亚砷酸细菌的进化，这种多样性可能部分是由水平基因转移事件引起的。能够进行亚砷酸盐氧化和亚砷酸盐流出机制的细菌具有较高的亚砷酸盐抗性水平。
BackgroundArsenic is known as a toxic metalloid, which primarily exists in inorganic form [As(III) and As(V)] and can be transformed by microbial redox processes in the natural environment. As(III) is much more toxic and mobile than As(V), hence microbial arsenic redox transformation has a major impact on arsenic toxicity and mobility which can greatly influence the human health. Our main purpose was to investigate the distribution and diversity of microbial arsenite-resistant species in three different arsenic-contaminated soils, and further study the As(III) resistance levels and related functional genes of these species.ResultsA total of 58 arsenite-resistant bacteria were identified from soils with three different arsenic-contaminated levels. Highly arsenite-resistant bacteria (MIC > 20 mM) were only isolated from the highly arsenic-contaminated site and belonged toAcinetobacter,Agrobacterium,Arthrobacter,Comamonas,Rhodococcus,StenotrophomonasandPseudomonas. Five arsenite-oxidizing bacteria that belonged toAchromobacter,AgrobacteriumandPseudomonaswere identified and displayed a higher average arsenite resistance level than the non-arsenite oxidizers. 5aoxBgenes encoding arsenite oxidase and 51 arsenite transporter genes [18arsB, 12ACR3(1) and 21ACR3(2)] were successfully amplified from these strains using PCR with degenerate primers. TheaoxBgenes were specific for the arsenite-oxidizing bacteria. Strains containing both an arsenite oxidase gene (aoxB) and an arsenite transporter gene (ACR3 or arsB) displayed a higher average arsenite resistance level than those possessing an arsenite transporter gene only. Horizontal transfer ofACR3(2) andarsBappeared to have occurred in strains that were primarily isolated from the highly arsenic-contaminated soil.ConclusionSoils with long-term arsenic contamination may result in the evolution of highly diverse arsenite-resistant bacteria and such diversity was probably caused in part by horizontal gene transfer events. Bacteria capable of both arsenite oxidation and arsenite efflux mechanisms had an elevated arsenite resistance level.
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影响因子：
6.1
作者：
Lenoble, V;Deluchat, V;Bollinger, JC
通讯作者：
Bollinger, JC
影响因子：
11.4
作者：
Macur, RE;Jackson, CR;Inskeep, WP
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5.1
作者：
Inskeep, William P.;Macur, Richard E.;Santini, Joanne M.
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影响因子：
3.2
作者：
López-Maury, L;Florencio, FJ;Reyes, JC
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Reyes, JC
影响因子：
9.5
作者：
Kumar, S;Tamura, K;Nei, M
通讯作者：
Nei, M