Characterization of the virulence potential of Staphylococcus condimenti isolated from a patient with severe soft tissue infection

Abstract

The coagulase-negative bacterium Staphylococcus condimenti and closely related species are commonly isolated from or found in starter cultures of fermented sausage as well as fish and soy sauces, and have traditionally been considered nonpathogenic. Recently, however, a case of catheter-related bacteraemia caused by S. condimenti was reported. In the present study we identified and characterized a strain of S. condimenti isolated from a patient with a severe soft tissue infection, comparing it to S. condimenti and S. carnosus type strains in order to elucidate the virulence potential of the clinical strain. Genome comparison showed high degree of conservation between the clinical strain and the type strain used in food industry, as well as with S. carnosus. The genome of the clinical S. condimenti strain contains few horizontally transferred regions and 37 putative virulence genes, including genes with similarity to leucocidin and genes involved in immune evasion, proinflammatory and cytolytic activity. However, it remains to be tested whether these putative virulence genes are expressed and functional. Although uncommon, S. condimenti may cause severe infection in previously healthy persons.