Fig. 5.

β-Galactosidase release assays. Cell lysis of UAMS-1, KB1051 (cidA point mutant), and KB1052 (repaired KB1051), each constitutively expressing β-galactosidase, was monitored by measuring β-galactosidase release into the culture supernatant. White bars correspond to UAMS-1, dark-gray bars to KB1051, and light-gray bars to KB1052; values represent means from three independent experiments ± standard errors of the means (SEM). Significant differences were seen between UAMS-1 and KB1051 at both time points (P = 0.05 at 52 h and P < 0.001 at 72 h) as well as between KB1051 and KB1052 at both time points (P = 0.02 at 52 h and P = 0.007 at 72 h); however, no significant difference was observed between UAMS-1 and KB1052 at either time point.