Role of ompR-dependent genes in Salmonella typhimurium virulence: mutants deficient in both ompC and ompF are attenuated in vivo.
A Salmonella typhimurium strain harboring stable mutations in both ompC and ompF was constructed from the mouse-virulent strain S. typhimurium SL1344. When administered orally to BALB/c mice the strain was attenuated, with the 50% lethal dose (LD50) reduced by approximately 1,000-fold. However, the intravenous LD50 was reduced only by approximately 10-fold. The ompC ompF mutant persisted in murine tissues for several weeks following oral challenge, and mice immunized with this mutant were well protected against challenge with virulent SL1344. A strain harboring a stable mutation in tppB behaved in a manner similar to that of strain SL1344 in vivo, while a strain harboring mutations in ompC, ompF, and tppB behaved as an ompC ompF mutant in vivo, indicating that the tppB operon is not required for virulence in S. typhimurium.
Chatfield
S N
SN
Department of Molecular Biology, Wellcome Biotech, Bechenham, United Kingdom.
Dorman
C J
CJ
Hayward
C
C
Dougan
G
G
D000818:Animals; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D005798:Genes, Bacterial; D051379:Mice; D008807:Mice, Inbred BALB C; D009154:Mutation; D018272:Porins; D012486:Salmonella typhimurium / Q000235:genetics / Q000276:immunology / Q000472:pathogenicity*; D015534:Trans-Activators / Q000235:genetics*; D014774:Virulence
D001425:Bacterial Outer Membrane Proteins; D018272:Porins; D015534:Trans-Activators