Mutations conferring acid sensitivity in the acid-tolerant strains Rhizobium meliloti WSM419 and Rhizobium leguminosarum biovar viciae WSM710

@article{Tiwari1992MutationsCA,
  title={Mutations conferring acid sensitivity in the acid-tolerant strains Rhizobium meliloti WSM419 and Rhizobium leguminosarum biovar viciae WSM710},
  author={Ravi P. Tiwari and Wayne G Reeve and A. R. Gleenn},
  journal={Fems Microbiology Letters},
  year={1992},
  volume={100},
  pages={107-112}
}
The genetic basis of acid-tolerance in rhizobia is being investigated by the isolation and molecular characterisation of Tn5-induced acid-sensitive mutants. Strains of Rhizobium meliloti (the most acid-sensitive species of rhizobia) respond to increasing concentrations of calcium in the growth medium both by growing faster and by being able to grow at progressively lower pH. Two classes of acid-sensitive mutant of R. meliloti WSM419 (a relatively acid-tolerant inoculant strain) have been… 

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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).

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