FIG 8.
Quantitative peptide-binding assay for ApnI with subtilomycin. The cell suspensions (OD600 = 10) of stationary-phase-grown B. subtilis CU1065 and its recombinant expressing apnI were incubated with subtilomycin at concentrations of 15 μg/ml (A) and 25 μg/ml (B) in the presence of 1 M NaCl under the conditions described in Materials and Methods. The amounts of subtilomycin remaining in the supernatants (open bars) and the amounts remaining in the cell-associated samples (filled bars) were quantified by reverse-phase HPLC. Values represent means, with error bars representing standard deviations.