Evidence that Fusidic Acid Inhibits the Binding of Aminoacyl‐tRNA to the Donor as well as the Acceptor Site of the Ribosomes

Abstract

A relatively high concentration of fusidic acid (3 mM) inhibits the binding of aminoacyl‐tRNA to the donor as well as the acceptor site of ribosomes in the absence of elongation factor G (EF‐G). In the presence of EF‐G a low concentration of fusidic acid (1 mM) inhibited the nonenzymatic binding of aminoacyl‐tRNA to the donor and the acceptor site approximately 30% and 80%, respectively. On the other hand, binding of aminoacyl‐tRNA to the acceptor site which is dependent on elongation factor T, was specifically inhibited by, EF‐G, GTP and fusidic acid. From these observations, it is suggested that the binding site of fusidic acid, GDP and EF‐G may not be strictly located at the acceptor site. Copyright © 1973, Wiley Blackwell. All rights reserved