Altered stationary-phase response in a Borrelia burgdorferi rpoS mutant.
The homolog of the chromosomally encoded stationary-phase sigma factor RpoS in Borrelia burgdorferi was inactivated using gyrB(r) as a selectable marker. Two-dimensional nonequilibrium pH gradient electrophoresis of stationary-phase cell lysates identified at least 11 differences between the protein profiles of the rpoS mutant and wild-type organisms. Wild-type B. burgdorferi had a growth phase-dependent resistance to 1 N NaCl, similar to the stationary-phase response reported for other bacteria. The B. burgdorferi rpoS mutant strain was less resistant to osmotic stress in stationary phase than the isogenic rpoS wild-type organism. The results indicate that the B. burgdorferi rpoS homolog influences protein composition and participates in stationary-phase-dependent osmotic resistance. This rpoS mutant will be useful for studying regulation of gene expression in response to changing environmental conditions.
Elias
A F
AF
Laboratory of Human Bacterial Pathogenesis, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana 59840, USA. aelias@niaid.nih.gov
Bono
J L
JL
Carroll
J A
JA
Stewart
P
P
Tilly
K
K
Rosa
P
P
D001426:Bacterial Proteins / Q000235:genetics*; D015748:Borrelia burgdorferi Group / Q000235:genetics / Q000254:growth & development*; D005798:Genes, Bacterial; D016296:Mutagenesis; D009995:Osmosis; D012808:Sigma Factor / Q000235:genetics*; D012965:Sodium Chloride; D014158:Transcription, Genetic
D001426:Bacterial Proteins; D012808:Sigma Factor; C069567:sigma factor KatF protein, Bacteria; D012965:Sodium Chloride