Salt stress-induced changes in the transcriptome, compatible solutes, and membrane lipids in the facultatively phototrophic bacterium Rhodobacter sphaeroides.

ABSTRACT: Responses to NaCl stress were investigated in phototrophically grown Alphaproteobacterium Rhodobacter sphaeroides by transcriptome profiling, mutational analysis, and measurements of compatible solutes and membrane phospholipids. After exposure to salt stress, genes encoding two putative glycine betaine uptake systems, proVWX and betS, were highly upregulated. Mutational analysis revealed that BetS, not ProVWX, was the primary transporter of this compatible solute. Upon the addition of salt, exogenous glycine betaine was taken up rapidly, and maximal intracellular levels were reached within minutes. In contrast, synthesis of another important compatible solute in R. sphaeroides, trehalose, increased slowly following salt stress, reaching maximal levels only after several hours. This accumu

SUBMITTER: Tsuzuki M 

PROVIDER: S-EPMC3209165 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature