title: tmRNA from Thermus thermophilus. Interaction with alanyl-tRNA synthetase and elongation factor Tu.
abstract: The interaction of a Thermus thermophilus tmRNA transcript with alanyl-tRNA synthetase and elongation factor Tu has been studied. The synthetic tmRNA was found to be stable up to 70 degrees C. The thermal optimum of tmRNA alanylation was determined to be around 50 degrees C. At 50 degrees C, tmRNA transcript was aminoacylated by alanyl-tRNA synthetase with 5.9 times lower efficiency (kcat/Km) than tRNAAla, primarily because of the difference in turnover numbers (kcat). Studies on EF-Tu protection of Ala approximately tmRNA against alkaline hydrolysis revealed the existence of at least two different binding sites for EF-Tu on charged tmRNA. The possible nature of these binding sites is discussed.
authors.affiliation: Institute of Molecular and Structural Biology, University of Aarhus, Denmark.
authors.forename: Victor G
authors.initials: VG
authors.lastname: Stepanov
authors.forename: Jens
authors.initials: J
authors.lastname: Nyborg
mesh_terms: D000409:Alanine / Q000235:genetics / Q000378:metabolism; D000412:Alanine-tRNA Ligase / Q000378:metabolism*; D001483:Base Sequence; D001665:Binding Sites; D017931:DNA Primers / Q000737:chemistry; D024202:Electrophoretic Mobility Shift Assay; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D006153:Guanosine Diphosphate / Q000378:metabolism; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D010444:Peptide Elongation Factor Tu / Q000378:metabolism*; D010957:Plasmids; D016133:Polymerase Chain Reaction; D011485:Protein Binding; D012329:RNA, Bacterial / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D012343:RNA, Transfer / Q000378:metabolism*; D012344:RNA, Transfer, Ala; D012346:RNA, Transfer, Amino Acyl / Q000235:genetics / Q000378:metabolism; D016963:Thermus thermophilus / Q000235:genetics*
chemical_list: D017931:DNA Primers; D012329:RNA, Bacterial; D012333:RNA, Messenger; D012344:RNA, Transfer, Ala; D012346:RNA, Transfer, Amino Acyl; C096222:tmRNA; D006153:Guanosine Diphosphate; D012343:RNA, Transfer; D010444:Peptide Elongation Factor Tu; D000412:Alanine-tRNA Ligase; D000409:Alanine