title: Chromosomal organization and nucleotide sequence of the genes for elongation factors EF-1 alpha and EF-2 and ribosomal proteins S7 and S10 of the hyperthermophilic archaeum Desulfurococcus mobilis.
abstract: The Desulfurococcus mobilis genes fus (encoding EF-2) and tuf (for EF-1 alpha) were cloned and sequenced together with genes for ribosomal proteins S10 (rps10) and S7 (rps7). Unlike Methanococcus, which displays the bacterial-like fus and tuf gene context 5'-rps12-rps7-fus-tuf-3', and similar to Sulfolobus and Pyrococcus, the Desulfurococcus fus gene (734 codons) has a distinct chromosomal location. Moreover, tuf (441 codons) is the promoter-proximal unit of a three-gene cluster comprising the genes rps10 (98 codons) and tRNA(Ser); the arrangement of the cluster is 5'-tuf-91 bp spacer -rps10-138 bp spacer -tRNA(Ser)-3' and the tuf gene is preceded by a canonical archaeal promoter. The D. mobilis gene rps7 (198 codons) is located further upstream from tuf (535 bp 'silent' intergenic spacing) and no rps12 homolog occurs in its immediate vicinity. Also, judging from putative promoter and transcription termination sequences, rps7 appears to be separately transcribed. Analysis of the predicted fus and tuf gene products revealed the three consensus motifs characteristic of GTP-binding proteins, and the fus-encoded EF-2 protein also displayed the consensus sequence required for ADP-ribosylation by Diphtheria toxin. Both EF sequences were definitely crenarchaeal by comparison with available homologs from other Archaea. Outgroup-rooted phylogenies derived from the sequences of ribosomal proteins S10 and S7 yielded the Sulfolobus-Desulfurococcus association at a high bootstrap confidence level.
authors.affiliation: Instituto Pasteur Fondazione Cenci-Bolognetti, Dipartimento di Biopatologia Umana, Università di Roma I, Policlinico Umberto I, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Ceccarelli
authors.forename: M
authors.initials: M
authors.lastname: Bocchetta
authors.forename: R
authors.initials: R
authors.lastname: Creti
authors.forename: A M
authors.initials: AM
authors.lastname: Sanangelantoni
authors.forename: O
authors.initials: O
authors.lastname: Tiboni
authors.forename: P
authors.initials: P
authors.lastname: Cammarano
mesh_terms: D000595:Amino Acid Sequence; D001105:Archaea / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D002876:Chromosomes, Bacterial; D003001:Cloning, Molecular; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D009876:Operon / Q000235:genetics; D020648:Peptide Elongation Factor 1; D020652:Peptide Elongation Factor 2; D010445:Peptide Elongation Factors / Q000235:genetics; D010802:Phylogeny; D012269:Ribosomal Proteins / Q000235:genetics*; D017386:Sequence Homology, Amino Acid
chemical_list: D001426:Bacterial Proteins; D020648:Peptide Elongation Factor 1; D020652:Peptide Elongation Factor 2; D010445:Peptide Elongation Factors; D012269:Ribosomal Proteins; C029537:ribosomal protein S10; C037442:ribosomal protein S7