Identification of the genetic basis for clinical menadione-auxotrophic small-colony variant isolates of Staphylococcus aureus.

ABSTRACT: Small-colony variants (SCVs) of Staphylococcus aureus are associated with persistent infections and may be selectively enriched during antibiotic therapy. Three pairs of clonally related S. aureus isolates were recovered from patients receiving systemic antibiotic therapy. Each pair consisted of an isolate with a normal phenotype and an isolate with an SCV phenotype. These SCVs were characterized by reduced susceptibility to gentamicin, reduced hemolytic activity, slow growth, and menadione auxotrophy. Sequencing of the genes involved in menadione biosynthesis revealed mutations in menB, the gene encoding naphthoate synthase, in all three strains with the SCV phenotype. The menB mutations were (i) a 9-bp deletion from nucleotides 55 to 63, (ii) a frameshift mutation that resulted in a prem

SUBMITTER: Lannergard J 

PROVIDER: S-EPMC2573106 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature