title: The 2.9 A crystal structure of T. thermophilus seryl-tRNA synthetase complexed with tRNA(Ser).
abstract: The crystal structure of Thermus thermophilus seryl-transfer RNA synthetase, a class 2 aminoacyl-tRNA synthetase, complexed with a single tRNA(Ser) molecule was solved at 2.9 A resolution. The structure revealed how insertion of conserved base G20b from the D loop into the core of the tRNA determines the orientation of the long variable arm, which is a characteristic feature of most serine specific tRNAs. On tRNA binding, the antiparallel coiled-coil domain of one subunit of the synthetase makes contacts with the variable arm and T psi C loop of the tRNA and directs the acceptor stem of the tRNA into the active site of the other subunit. Specificity depends principally on recognition of the shape of tRNA(Ser) through backbone contacts and secondarily on sequence specific interactions.
authors.affiliation: European Molecular Biology Laboratory, Grenoble Outstation, France.
authors.forename: V
authors.initials: V
authors.lastname: Biou
authors.forename: A
authors.initials: A
authors.lastname: Yaremchuk
authors.forename: M
authors.initials: M
authors.lastname: Tukalo
authors.forename: S
authors.initials: S
authors.lastname: Cusack
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000595:Amino Acid Sequence; D001482:Base Composition; D001483:Base Sequence; D001665:Binding Sites; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D012346:RNA, Transfer, Amino Acyl / Q000737:chemistry* / Q000378:metabolism; D012714:Serine-tRNA Ligase / Q000737:chemistry* / Q000378:metabolism; D013379:Substrate Specificity; D016963:Thermus thermophilus / Q000201:enzymology*
chemical_list: D012346:RNA, Transfer, Amino Acyl; D000255:Adenosine Triphosphate; D012714:Serine-tRNA Ligase