Specific alterations of the EF-Tu polypeptide chain considered in the light of its three-dimensional structure.

摘要: Specific alterations of the elongation factor Tu (EF-Tu) polypeptide chain have been identified in a number mutant species this factor. In two species, Ala-375, located on domain II, was found by amino acid analysis to be replaced Thr and Val, respectively. These replacements substantially lower affinity EF-Tu.GDP for antibiotic kirromycin. Since kirromycin can cross-linked Lys-357, also II but structurally very far from these data suggest that alter relative position domains I II. The Ala-375 dissociation rates binary complexes EF-Tu.GTP binding constants Phe-tRNA. It is conceivable effects are mediated movements each other. Replacement Gly-222 Asp has another DNA sequence cloned tufB gene, coding EF-Tu. part structural domain, characteristic variety nucleotide enzymes. Its replacement does not abolish ability EF-Tu sustain protein synthesis. increases rate approximately 30%. presence bind ribosome, contrast its wild-type counterpart. A possible explanation now open experimental verification.