Evaluation of selected features of Staphylococcus cohnii enabling colonization of humans.

Based on iron utilization, sensitivity to skin fatty acids, lipolytic and proteolytic activity the potential abilities of Staphylococcus cohnii strains to colonize humans were evaluated. The investigation included 60 strains that belong to both subspecies, viz. S. cohnii ssp. cohnii and S. cohnii ssp. urealyticus. Strains were isolated from different sources of the Intensive Care Unit and from non-hospital environment. Most of the strains were multiple antibiotic-resistant. Strains of both subspecies revealed a relatively low iron requirement. These strains were capable of utilizing iron bound in oxo acids and from host iron-binding proteins. S. cohnii ssp. urealyticus were more effective in iron uptake than S. cohnii ssp. cohnii. All investigated strains revealed sensitivity to skin fatty acids, but S. cohnii ssp. urealyticus strains were more resistant. Special features of strains of this subspecies promote colonization of humans.