title: A highly conserved family of inactivated archaeal B family DNA polymerases.
abstract: A widespread and highly conserved family of apparently inactivated derivatives of archaeal B-family DNA polymerases is described. Phylogenetic analysis shows that the inactivated forms comprise a distinct clade among archaeal B-family polymerases and that, within this clade, Euryarchaea and Crenarchaea are clearly separated from each other and from a small group of bacterial homologs. These findings are compatible with an ancient duplication of the DNA polymerase gene followed by inactivation and parallel loss in some of the lineages although contribution of horizontal gene transfer cannot be ruled out. The inactivated derivative of the archaeal DNA polymerase could form a complex with the active paralog and play a structural role in DNA replication.
authors.affiliation: National Center for Biotechnology Information NLM, National Institutes of Health, Bethesda, MD, 20894, USA. rogozin@ncbi.nlm.nih.gov
authors.forename: Igor B
authors.initials: IB
authors.lastname: Rogozin
authors.forename: Kira S
authors.initials: KS
authors.lastname: Makarova
authors.forename: Youri I
authors.initials: YI
authors.lastname: Pavlov
authors.forename: Eugene V
authors.initials: EV
authors.lastname: Koonin
mesh_terms: D001105:Archaea / Q000201:enzymology* / Q000235:genetics*; D019843:Archaeal Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000145:classification / Q000235:genetics; D020134:Catalytic Domain / Q000235:genetics; D017124:Conserved Sequence; D004261:DNA Replication / Q000235:genetics; D004259:DNA-Directed DNA Polymerase / Q000737:chemistry / Q000145:classification / Q000235:genetics; D019143:Evolution, Molecular; D005810:Multigene Family; D019384:Nucleic Acid Synthesis Inhibitors; D010802:Phylogeny; D021122:Protein Subunits / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000145:classification / Q000235:genetics; D011544:Pseudogenes / Q000235:genetics
chemical_list: D019843:Archaeal Proteins; D019384:Nucleic Acid Synthesis Inhibitors; D021122:Protein Subunits; D004259:DNA-Directed DNA Polymerase