Figure 5.
Effect of acidomycin on the activity of biotin synthase in a protein extract from E. coli cells overproducing Bio2 from Arabidopsis (in vitro heterologous system). Biotin synthase activity was measured under optimized conditions with 1.5 mg of protein extract. Reaction mixtures were incubated for 2 h. A, Biotin formed was determined by TLC analysis and phosphorimaging quantitation (conversion of [3H]DTB to [3H]biotin). Lane 1, DTB and biotin standards; lane 2, assay in the absence of acidomycin; lane 3, assay in the presence of 400 μm acidomycin. B, Effect of increasing concentrations of acidomycin on biotin synthase activity. Biotin produced was determined by a turbidimetric microbiological method using L. plantarum.