<p>Members of this family possess translation elongation factor activity. They have been shown to stimulate efficient translation and peptide-bond synthesis on native or reconstituted 70S ribosomes in vitro, possibly indirectly by altering the affinity of the ribosome for aminoacyl-tRNA, thus increasing their reactivity as acceptors for peptidyl transferase (by similarity) [<cite idref="PUB00000702"/>]. This family does not include members of <db_xref db="INTERPRO" dbkey="IPR011897"/>, an EFP-like protein of certain gammaproteobacteria.</p>