title: A dnaK homolog in the archaebacterium Methanosarcina mazei S6.
abstract: A fragment of genomic DNA cloned from the methanogenic archaebacterium, Methanosarcina mazei strain S6, was found to contain an 1857-bp open reading frame (ORF). A sequence matching the consensus ribosome-binding sequence determined for other methanogens was found upstream from the ORF. The amino acid (aa) sequence encoded by the ORF was compared with reference sequences and was found to be related to six DnaK sequences determined for five species of eubacteria (none exist for archaebacteria). The M. mazei S6 aa sequence was over 61% identical and over 77% similar (identities plus conservative substitutions) to the closest four reference sequences, which were all DnaKs. The gene described here is therefore proposed to be the first member of the dnaK family sequenced from the archaebacterial kingdom (Archaea). This finding confirms that DnaK proteins are highly conserved, occurring not only in eubacteria (Bacteria) and eukaryotes (Eucaria), but also in archaebacteria (Archaea).
authors.affiliation: Wadsworth Center for Laboratories and Research, New York State Department of Health, Albany.
authors.forename: A J
authors.initials: AJ
authors.lastname: Macario
authors.forename: C B
authors.initials: CB
authors.lastname: Dugan
authors.forename: E
authors.initials: E
authors.lastname: Conway de Macario
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000235:genetics*; D017020:Methanosarcina / Q000235:genetics*; D008969:Molecular Sequence Data; D016366:Open Reading Frames / Q000235:genetics; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid
chemical_list: D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins; C063842:dnaK protein, E coli