Proteomic and molecular investigations revealed that Acidithiobacillus caldus adopts multiple strategies for adaptation to NaCl stress
Proteomic and molecular investigations revealed that Acidithiobacillus caldus adopts multiple strategies for adaptation to NaCl stress
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蛋白质组学和分子研究表明，Acidithiobacillus caldus 采用多种策略来适应 NaCl 胁迫
DOI：
10.1007/s11434-013-0039-y
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发表时间：
2014-01-01
影响因子：
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通讯作者：
Liu, Shuangjiang
中科院分区：
文献类型：
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作者：
Guo, Xu;Jiang, Chengying;Liu, Shuangjiang
酸性钙化硫杆菌在工业生物浸出中起着重要作用。为了了解愈伤甘蓝对NaCl胁迫的适应机制，我们在高浓度NaCl培养基中培养愈伤甘蓝菌株SM-1。SM-1在1.0 mol L−1 NaCl浓度下生长，但在较高的NaCl浓度下生长受到严重抑制。蛋白质组学分析表明，SM-1对NaCl胁迫有多种响应策略。除了几种热休克蛋白外，在NaCl胁迫下，参与脯氨酸生物合成的酶也增加了。另外，两种dna结合蛋白和第三种功能未知的蛋白（Atc_1291）在NaCl胁迫下表达上调，Atc_1291被认为是单链dna结合蛋白。这些dna结合蛋白可能在对渗透胁迫的反应中起作用。克隆Atc_1291并在大肠杆菌中表达。令人惊讶的是，我们发现大肠杆菌BL21/pET28a-atc_1291的细胞密度高于大肠杆菌BL21/pET28a，无论NaCl胁迫如何。在变形菌门的几个类群中发现了Atc_1291的同源物。Atc_1291在促进细胞生长中的作用有待进一步研究。
Acidithiobacillus caldus plays an important role in commercial bioleaching. To understand how NaCl stress adaptation occurs in A. caldus, we grew A. caldus strain SM-1 in media containing high NaCl concentrations. SM-1 grew at concentrations of up to 1.0-mol L−1 NaCl, but growth was severely inhibited at higher concentrations. Proteomic analysis showed that SM-1 used multiple strategies to respond to NaCl stress. In addition to several heat-shock proteins, enzymes involved in proline biosynthesis increased under NaCl stress. In addition, two DNA-binding proteins and a third protein of unknown function (Atc_1291), which was subsequently identified as a putative single-stranded DNA-binding protein, were up-regulated in the presence of NaCl stress. These DNA-binding proteins might play a role in response to osmotic stress. Atc_1291 was cloned and expressed in Escherichia coli. Surprisingly, we found that E. coli BL21/pET28a-atc_1291 grew to higher cell densities than E. coli BL21/pET28a, regardless of NaCl stress. Homologs to Atc_1291 were identified in several groups of Proteobacteria. The role of Atc_1291 in enhancing cell growth needs further investigation.