Fig. 5.

Tests of the altered specificity variant AgrC-I-I171K with various AIPs. (A) β-Lactamase reporter cells expressing AgrC-I-I171K were incubated with increasing doses of the indicated AIP. (B) Cells expressing AgrC-I WT or I171K were assayed without or with AIP-I (1 μM) or the indicated supernatant. (C–E) Inhibition assays. AgrC-I WT or I171K was assayed with increasing concentrations of AIP-II (C) or S. epidermidis AIP (D) in the presence of a constant dose (50 nM) of AIP-I. (E) The indicated supernatant was added in the presence of AIP-I at 25 nM. Data are presented as percent maximal activation ± SEM.