Correlation of Effects of Erythromycin Analogues on Intact Bacteria and on [ 14 C]Erythromycin Binding to Escherichia coli Ribosomes

Abstract

The dissociation constants for binding to ribosomes from Escherichia coli and concentrations at which 50% inhibition of [ ¹⁴ C]erythromycin binding to ribosomes occurred were determined for 45 erythromycin analogues. These values were correlated with their antibacterial activities against Bacillus subtilis . Compounds which bound to ribosomes best showed the greatest activities; those which were poorly bound to ribosomes showed little or no antibacterial activity. The ribosomal binding assays therefore reflected the general antibacterial potential of the erythromycin analogues.