A Salmonella typhimurium mutant unable to utilize fatty acids and citrate is avirulent and immunogenic in mice.
Salmonella typhimurium SR-11 is extremely virulent at a dose as low as 10(5) colony forming units (cfu) when administered perorally to BALB/c mice. Utilizing mini-transposon mutagenesis, a mutant of S. typhimurium SR-11 was isolated that was unable to utilize oleate and citrate as carbon sources. This mutant, designated S. typhimurium SR-11 Fad- (Fatty acid), was found to utilize sugars under cya/crp control as sole carbon sources, suggesting that the mutation is not in either of these genes. In addition, SR-11 Fad- utilized pyruvate and succinate, but was unable to utilize either acetate or isocitrate as sole carbon source. In contrast to SR-11, SR-11 Fad- was found to be avirulent, i.e. BALB/c mice were completely healthy after oral infection with 10(9) S. typhimurium SR-11 Fad- cells. Moreover, 21 days after SR-11 Fad- infection, BALB/c mice were found to be protected against an oral challenge with 10(9) cells of S. typhimurium SR-11.
Department of Biochemistry, Microbiology, and Molecular Genetics, University of Rhode Island, Kingston 02881, USA.
M
M
Utley
D P
DP
Franklin
K A
KA
Krogfelt
D C
DC
Laux
P S
PS
Cohen
D000818:Animals; D001428:Bacterial Vaccines / Q000276:immunology*; D019343:Citric Acid / Q000378:metabolism; D004251:DNA Transposable Elements / Q000235:genetics; D005227:Fatty Acids / Q000378:metabolism; D005243:Feces / Q000382:microbiology; D008099:Liver / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D016254:Mutagenesis, Insertional; D012481:Salmonella Infections, Animal / Q000517:prevention & control; D012486:Salmonella typhimurium / Q000235:genetics / Q000276:immunology* / Q000378:metabolism / Q000472:pathogenicity*; D013154:Spleen / Q000382:microbiology; D014611:Vaccination; D014774:Virulence
D001428:Bacterial Vaccines; D004251:DNA Transposable Elements; D005227:Fatty Acids; D019343:Citric Acid