Substrate- and Antibiotic-Binding Sites at the Peptidyl-Transferase Centre of <em>Escherichia coli</em> Ribosomes.

In Escherichia coli there is one binding site per ribosome for lincomycin, chloramphenicol and erythromycin. These antibiotics act at closely related sites on the 50-S subunit. There are, however, some interesting differences m the properties of the three sites, such as: (a) the apparent possibility of obstructing the lincomycin site without closing the chloramphenicol site, (b) asymmetry of competition effects between chloramphenicol and erythromycin, (c) differential responses to ethanol and (d) differential responses to other antibiotics (puromycin, macrolides, streptogramins A and B and others also acting on the larger ribosome subunit). [ABSTRACT FROM AUTHOR]