Acid tolerance in Rhizobium meliloti strain WSM419 involves a two-component sensor-regulator system.

@article{Tiwari1996AcidTI,
  title={Acid tolerance in Rhizobium meliloti strain WSM419 involves a two-component sensor-regulator system.},
  author={R. Tiwari and W. Reeve and M. Dilworth and A. Glenn},
  journal={Microbiology},
  year={1996},
  volume={142 ( Pt 7)},
  pages={
          1693-704
        }
}
An acid-sensitive mutant, TG5-46, derived from Rhizobium meliloti WSM419 by Tn5 mutagenesis, fails to grow below pH 6.0 whereas the parent strain grows at pH 5.7. The DNA sequence of a 2.2 kb rhizobial DNA region flanking Tn5 in TG5-46 contains two open reading frames, ORF1 (designated actS) and ORF2 (designated actR), having high similarity to the sensor-regulator pairs of the two-component systems involved in signal transduction in prokaryotes. Insertion of an omega interposon into actS in R… Expand
The transcriptional regulator gene phrR in Sinorhizobium meliloti WSM419 is regulated by low pH and other stresses.
TLDR
The phrR gene in Sinorhizobium meliloti WSM419, directly downstream from actA, is induced by low pH or certain stresses, but not in stationary phase or by other stresses (e.g. phosphate limitation, elevated temperature, high concentrations of sucrose or iron). Expand
Regulation of exopolysaccharide production in Rhizobium leguminosarum biovar viciae WSM710 involves exoR.
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The data suggest that Tn5 has disrupted a regulatory gene encoding a protein that negatively modulates EPS biosynthesis in R. leguminosarum bv. Expand
The Two-Component System ActJK is Involved in Acid Stress Tolerance and Symbiosis in Sinorhizobium meliloti.
TLDR
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A histidine kinase sensor protein gene is necessary for induction of low pH tolerance in Sinorhizobium sp. strain BL3
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It was shown that actX was induced at low pH and the method of gene identification used in this study for isolation of actX may be applied for the isolation of other genes involved in tolerance to adverse environmental factors. Expand
The Sinorhizobium medicae WSM419 lpiA gene is transcriptionally activated by FsrR and required to enhance survival in lethal acid conditions.
TLDR
Although acid-activated lpiA transcription was not required for cell growth, its expression was crucial in enhancing the viability of cells subsequently exposed to lethal acid conditions and therefore this lipid cannot be a major constituent of S. medicae membranes. Expand
ActP controls copper homeostasis in Rhizobium leguminosarum bv. viciae and Sinorhizobium meliloti preventing low pH‐induced copper toxicity
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Probing for pH-Regulated Genes in Sinorhizobium medicae Using Transcriptional Analysis
TLDR
Findings implicate cytochrome synthesis, potassium ion cycling, lipid biosynthesis and transport processes as key components of pH response in S. medicae. Expand
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Molecular genetic analysis of multiple rpoH and groEL genes in Sinorhizobium meliloti
TLDR
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TLDR
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