Exchange of free GTP with EF-1α·GDP complex promoted by a factor EF-1β from pig liver

Abstract

Eukaryotic polypeptide chain elongation factor 1 (EF-1) has been resolved into two complementary factors, EF-1α and EF-1β, both of which were purified. Recently, we find that [ 3H] GDP bound to purified EF-1α is replaced by exogenous GTP rather slowly when the reaction is carried out at ionic strength optimal for polyphenylalanine synthesis. EF-1β stimulates the exchange of free GTP with EF-1α·GDP, indicating that the function of EF-1β is, at least in part, similar to that of bacterial EF-Ts.