Slime production and expression of the slime-associated antigen by staphylococcal clinical isolates

The ability to produce slime and to express a slime-associated antigen was examined in a collection of staphylococcal clinical isolates. Slime-produci ng strains were found among coagulase-negative staphylococci in percentages comparable to those reported in other studies; surprisingly, a high percen tage of Staphylococcus aureus strains also were able to produce this extrac ellular material. In the fatter case, this ability was strongly dependent o n the presence of an additional carbohydrate source in the growth medium. E xpression of the slime-associated antigen appeared to be species specific a nd confined to the Staphylococcus epidermidis sensu stricto isolates; its s trong association with the ability of these strains to produce thicker biof ilms indicated slime-associated antigen as a possible virulence marker for S. epidermidis.