title: Nucleotide and aminoacyl-tRNA specificity of the mammalian mitochondrial elongation factor EF-Tu.Ts complex.
abstract: The bovine mitochondrial elongation factor Tu.Ts complex (EF-Tu.Tsmt) promotes the binding of aminoacyl-tRNA to ribosomes. In the presence of GTP, this complex functions catalytically. Both dGTP and ddGTP can replace GTP although about 4-fold higher concentrations are required. ATP, CTP and UTP are not active. ITP can replace GTP when used at 10- to 20-fold higher concentrations. The catalytic use of EF-Tu.Tsmt is inhibited by GDP but not by GMP. XDP also inhibits although about 20-fold higher concentrations are required. EF-Tu.Tsmt will promote the binding of Phe-tRNA to either Escherichia coli or mitochondrial ribosomes. Unlike E. coli EF-Tu, EF-Tu.Tsmt will promote the binding of AcPhe-tRNA to ribosomes about 25% as efficiently as Phe-tRNA. EF-Tu.Tsmt is active in catalyzing the binding of E. coli Met-tRNAmmet to ribosomes. EF-Tu.Tsmt has about 30% as much activity with E. coli Met-tRNAimet but has essentially no activity with E. coli fMet-tRNAimet. Neither yeast Met-tRNAimet nor fMet-tRNAimet is recognized by bovine EF-Tu.Tsmt.
authors.affiliation: Department of Chemistry, University of North Carolina, Chapel Hill 27599-3290, USA.
authors.forename: V L
authors.initials: VL
authors.lastname: Woriax
authors.forename: G H
authors.initials: GH
authors.lastname: Spremulli
authors.forename: L L
authors.initials: LL
authors.lastname: Spremulli
mesh_terms: D000215:Acylation; D000818:Animals; D002417:Cattle; D008928:Mitochondria / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D009711:Nucleotides / Q000378:metabolism; D010444:Peptide Elongation Factor Tu / Q000235:genetics* / Q000378:metabolism; D010445:Peptide Elongation Factors / Q000235:genetics / Q000378:metabolism*; D012331:RNA, Fungal / Q000378:metabolism; D012343:RNA, Transfer / Q000235:genetics* / Q000378:metabolism*; D012346:RNA, Transfer, Amino Acyl / Q000235:genetics / Q000378:metabolism; D012358:RNA, Transfer, Met / Q000378:metabolism; D012360:RNA, Transfer, Phe / Q000378:metabolism; D012270:Ribosomes / Q000235:genetics / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D009711:Nucleotides; D010445:Peptide Elongation Factors; D012331:RNA, Fungal; D012346:RNA, Transfer, Amino Acyl; D012358:RNA, Transfer, Met; D012360:RNA, Transfer, Phe; C023512:elongation factor Ts; D012343:RNA, Transfer; D010444:Peptide Elongation Factor Tu