Transcriptomics analysis defines global cellular response of Agrobacterium tumefaciens 5A to arsenite exposure regulated through the histidine kinases PhoR and AioS
Transcriptomics analysis defines global cellular response of Agrobacterium tumefaciens 5A to arsenite exposure regulated through the histidine kinases PhoR and AioS
复制标题
DOI：
10.1111/1462-2920.14577
复制
发表时间：
2019-08-01
影响因子：
5.1
通讯作者：
McDermott, Timothy R.
中科院分区：
文献类型：
--
作者：
Rawle, Rachel A.;Kang, Yoon-Suk;McDermott, Timothy R.
在砷和微生物共存的环境中，微生物是砷形态形成的主要驱动力，直接影响生物利用度、毒性和生物累积。形态反应影响砷在环境系统中的行为，直接影响人类和农业的暴露。亚砷酸盐氧化降低了砷的毒性和在环境中的流动性，因此了解其对细胞代谢的调节和整体影响具有重要意义。亚砷酸盐氧化酶（AioBA）由三组分信号转导系统AioXSR调节，AioXSR又由磷酸盐胁迫反应调节，其中PhoR作为主调节剂。使用RNA测序，我们的特点是砷对根癌农杆菌5A基因表达的全球影响。为了进一步阐明调节控制，采用组氨酸激酶PhoR和AioS的突变株，并说明除了砷代谢外，平行调节许多其他功能反应。受影响的功能包括砷和磷酸盐代谢、碳水化合物代谢、溶质转运系统和铁代谢等。这些研究结果有助于显着的代谢影响和遗传电路参与砷暴露在细菌中的当前的理解。这说明砷污染将如何影响涉及自然界几个地球化学循环的微生物活动。
In environments where arsenic and microbes coexist, microbes are the principal drivers of arsenic speciation, which directly affects bioavailability, toxicity and bioaccumulation. Speciation reactions influence arsenic behaviour in environmental systems, directly affecting human and agricultural exposures. Arsenite oxidation decreases arsenic toxicity and mobility in the environment, and therefore understanding its regulation and overall influence on cellular metabolism is of significant interest. The arsenite oxidase (AioBA) is regulated by a three-component signal transduction system AioXSR, which is in turn regulated by the phosphate stress response, with PhoR acting as the master regulator. Using RNA-sequencing, we characterized the global effects of arsenite on gene expression in Agrobacterium tumefaciens 5A. To further elucidate regulatory controls, mutant strains for histidine kinases PhoR and AioS were employed, and illustrate that in addition to arsenic metabolism, a host of other functional responses are regulated in parallel. Impacted functions include arsenic and phosphate metabolism, carbohydrate metabolism, solute transport systems and iron metabolism, in addition to others. These findings contribute significantly to the current understanding of the metabolic impact and genetic circuitry involved during arsenite exposure in bacteria. This informs how arsenic contamination will impact microbial activities involving several biogeochemical cycles in nature.