Characterization of a Tn925-induced mutant of Staphylococcus aureus altered in exoprotein production.
An insertional mutant was isolated from a bovine Staphylococcus aureus strain after membrane-mating with a Streptococcus faecalis strain carrying conjugative plasmid pCF10::Tn925. This mutant, designated RC128, showed enhanced production of alpha-hemolysin and proteases and decreased production of coagulase, extracellular protein A, DNase, lipase and delta-hemolysin. No difference was found in the production of beta-hemolysin. Both, Southern blot analysis and transfer of the pleiotropic mutant phenotype by transduction, indicated that the mutation was originated from a single insertion of transposon Tn925. The LD50 determined by intraperitoneal administration in mice showed that mutant RC128 was slightly less virulent than its parental strain.
Giraudo
A T
AT
Departmento de Microbiología, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional Río Cuarto, Córdoba.
Martínez
G L
GL
Calzolari
A
A
Nagel
R
R
D000818:Animals; D001426:Bacterial Proteins / Q000096:biosynthesis*; D002417:Cattle; D003227:Conjugation, Genetic; D004251:DNA Transposable Elements / Q000235:genetics*; D004269:DNA, Bacterial / Q000032:analysis; D013293:Enterococcus faecalis / Q000235:genetics; D007928:Lethal Dose 50; D008413:Mastitis / Q000382:microbiology; D051379:Mice; D009154:Mutation / Q000502:physiology*; D010641:Phenotype; D013211:Staphylococcus aureus / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D014774:Virulence
D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D004269:DNA, Bacterial