FIG. 4.
(A) Comparison of HPLC analyses of ethyl acetate extracts from S. ambofaciens wild-type (WT) and noncomplemented and complemented SVC1 strains. The arrows indicate the peak corresponding to the alpomycin antibiotic. Detection was carried out at 250 nm. A linear gradient from 40 to 98% acetonitrile was applied in the presence of 0.1% trifluoroacetic acid with a flow rate of 1 ml · min−1. (B) Bioassays of the HPLC fractions corresponding to the dotted line for antibacterial activity against B. subtilis ATCC 6633.