FIG. 5.

Semiquantitative biofilm assay. Each experiment was repeated eight times. A, Biofilm formation of S. epidermidis 1457, its isogenic ΔluxS mutant, the mutant with the empty vector, and the luxS-complemented mutant at 24 h. B, Biofilm formation of S. epidermidis 1457, its isogenic ΔluxS mutant, and the mutants with exogenous AI-2 prepared from wild-type and complemented mutant strains at 24 h using mutant with CM from mutant strain transformed with empty vector as control.