ELONGATION-FACTORS EF-G FROM ESCHERICHIA-COLI AND MAMMALIAN MITOCHONDRIA ARE NOT FUNCTIONALLY INTERCHANGEABLE

Salt-washed ribosomes from bovine mitochondria and E. coli require homologous factor preparations for activity in poly (U)-directed systems for phenylalanine polymerization, contrary to the widespread notion that bacterial and mitochondrial elongation factors are functionally interchangeable. The elongation factor EF-G of E. coli and its equivalent in bovine mitochondria cannot substitute for each other in the EF-G-dependent GTPase reaction of bacterial and mitochondrial ribosomes. © 1979.