Proteomic and molecular investigations revealed that Acidithiobacillus caldus adopts multiple strategies for adaptation to NaCl stress  

作　　者：Xu Guo Chengying Jiang Yuanming Luo Mingjiang Zhang Ansgar Poetsch Shuangjiang Liu 

机构地区：[1]State Key Laboratory of Microbial Resources,Institute of Microbiology,Chinese Academy of Sciences [2]University of Chinese Academy of Sciences [3]Environmental Microbiology and Biotechnology Research Center,Institute of Microbiology,Chinese Academy of Sciences [4]Lehrstuhl for Biochemie der Pflanzen,Ruhr Universitaet

出　　处：《Chinese Science Bulletin》2014年第3期301-309,共9页

基　　金：supported by the National High Technology Research and Development Program of China(2012AA061501);the National Key Basic Research and Development Program of China(2010CB630903);the National Natural Sciences Foundation of China(31171234)

摘　　要：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 heatshock 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 NaCI stress.Homologs to Atc_(1291)were identified in several groups of Proleohacleria.The role of Atc_(1291)in enhancing cell growth needs further investigation.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 NaCi concentrations. SM-I 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-I used multiple strategies to respond to NaCI 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 puta- tive 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 NaCi stress. Homologs to Atc_1291 were identified in several groups of Proteobacteria. The role of Atc_1291 in enhancing cell growth needs further investigation.

关 键 词：蛋白质组学 盐胁迫 DNA结合蛋白 NACL胁迫 显示 分子 抑制浓度 大肠杆菌 

分 类 号：Q51[生物学—生物化学] Q945.78