title: Cloning, expression and evolution of the gene encoding the elongation factor 1alpha from a low thermophilic Sulfolobus solfataricus strain.
abstract: The gene encoding the elongation factor 1alpha (EF-1alpha) from the archaeon Sulfolobus solfataricus strain MT3 (optimum growth temperature 75 degrees C) was cloned, sequenced and expressed in Escherichia coli. The structural and biochemical properties of the purified enzyme were compared to those of EF-1alpha isolated from S. solfataricus strain MT4 (optimum growth temperature 87 degrees C). Only one amino acid change (Val15-->Ile) was found. Interestingly, the difference was in the first guanine nucleotide binding consensus sequence G(13)HIDHGK and was responsible for a reduced efficiency in protein synthesis, which was accompanied by an increased affinity for both guanosine diphosphate (GDP) and guanosine triphosphate (GTP), and an increased efficiency in the intrinsic GTPase activity. Despite the different thermophilicities of the two microorganisms, only very marginal effects on the thermal properties of the enzyme were observed. Molecular evolution among EF-1alpha genes from Sulfolobus species showed that the average rate of nucleotide substitution per site per year (0.0312x10(-9)) is lower than that reported for other functional genes.
authors.affiliation: Dipartimento di Scienze Farmacobiologiche, Università di Catanzaro 'Magna Graecia', Roccelletta di Borgia, 88021, Catanzaro, Italy.
authors.forename: Mariorosario
authors.initials: M
authors.lastname: Masullo
authors.forename: Piergiuseppe
authors.initials: P
authors.lastname: Cantiello
authors.forename: Annalisa
authors.initials: A
authors.lastname: Lamberti
authors.forename: Olimpia
authors.initials: O
authors.lastname: Longo
authors.forename: Antonio
authors.initials: A
authors.lastname: Fiengo
authors.forename: Paolo
authors.initials: P
authors.lastname: Arcari
mesh_terms: D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D019143:Evolution, Molecular; D019848:Gene Expression Regulation, Archaeal; D019766:Genes, Archaeal; D006358:Hot Temperature; D020648:Peptide Elongation Factor 1 / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D017434:Protein Structure, Tertiary; D016944:Sulfolobus / Q000145:classification / Q000235:genetics*
chemical_list: D020648:Peptide Elongation Factor 1