FIG. 1.

Time course of β-galactosidase expression in JH39 and the xerD and ftsK mutants. Overnight cultures of each strain were diluted and grown in LB at 37°C until the OD₆₀₀ reached approximately 0.5 (zero time point). At the indicated time points, 1-ml samples were removed and assayed for β-galactosidase activity. Values represent the average of results of three independent experiments, with standard deviations indicated by error bars.