The Isolation and Characterization of Elongation Factor eEF‐Ts from Krebs‐II Mouse‐Ascites‐Tumor Cells and Its Role in the Elongation Process

Abstract
A factor with activity similar to that described in other systems for the eukaryotic elongation factor eEF-Ts was isolated from the heavy aggregate form of eET-TH (formally named EF-1H). This protein has a MW of 52,000 under native conditions and of 25,500 under denaturing conditions. It stimulates eEF-Tu-dependent aminoacyl-tRNA binding to ribosomes and therefore eEF-Tu/eEF-G-dependent polyphenylalanine synthesis by ribosomes. It also stimulates GDP-GTP exchange in eEF-Tu.cntdot.GDP complexes. The removal of deacylated [Escherichia coli] tRNA from the ribosome is a GTP-dependent process. This report adds further support to the concept that a 3rd elongation factor, eEF-Ts, may be common to all systems in the eukaryotic domain.