. "The enzyme is required for accurate and efficient protein synthesis under certain stress conditions." . "May act as a fidelity factor of the translation reaction, by catalyzing a one-codon backward translocation of tRNAs on improperly translocated ribosomes." . "Back-translocation proceeds from a post-translocation (POST) complex to a pre-translocation (PRE) complex, thus giving elongation factor G a second chance to translocate the tRNAs correctly." . "Binds to ribosomes in a GTP-dependent manner." . . . "Elongation factor 4" . "GTP + H(2)O = GDP + phosphate." .