Uracil recognition by replicative DNA polymerases is limited to the archaea, not occurring with bacteria and eukarya.
Family B DNA polymerases from archaea such as Pyrococcus furiosus, which live at temperatures approximately 100 degrees C, specifically recognize uracil in DNA templates and stall replication in response to this base. Here it is demonstrated that interaction with uracil is not restricted to hyperthermophilic archaea and that the polymerase from mesophilic Methanosarcina acetivorans shows identical behaviour. The family B DNA polymerases replicate the genomes of archaea, one of the three fundamental domains of life. This publication further shows that the DNA replicating polymerases from the other two domains, bacteria (polymerase III) and eukaryotes (polymerases delta and epsilon for nuclear DNA and polymerase gamma for mitochondrial) are also unable to recognize uracil. Uracil occurs in DNA as a result of deamination of cytosine, either in G:C base-pairs or, more rapidly, in single stranded regions produced, for example, during replication. The resulting G:U mis-pairs/single stranded uracils are promutagenic and, unless repaired, give rise to G:C to A:T transitions in 50% of the progeny. The confinement of uracil recognition to polymerases of the archaeal domain is discussed in terms of the DNA repair pathways necessary for the elimination of uracil.
Wardle
Josephine
J
Institute for Cell and Molecular Biosciences (ICaMB), University of Newcastle, Newcastle upon Tyne NE2 4HH, UK.
Burgers
Peter M J
PM
Cann
Isaac K O
IK
Darley
Kate
K
Heslop
Pauline
P
Johansson
Erik
E
Lin
Li-Jung
LJ
McGlynn
Peter
P
Sanvoisin
Jonathan
J
Stith
Carrie M
CM
Connolly
Bernard A
BA
D000595:Amino Acid Sequence; D001105:Archaea / Q000201:enzymology*; D019843:Archaeal Proteins / Q000737:chemistry / Q000378:metabolism*; D004247:DNA / Q000737:chemistry; D004258:DNA Polymerase III / Q000378:metabolism; D004261:DNA Replication; D004259:DNA-Directed DNA Polymerase / Q000737:chemistry / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology; D006801:Humans; D017020:Methanosarcina / Q000201:enzymology; D020027:Pyrococcus furiosus / Q000201:enzymology; D012441:Saccharomyces cerevisiae / Q000201:enzymology; D016415:Sequence Alignment; D013698:Templates, Genetic; D014498:Uracil / Q000378:metabolism*
D019843:Archaeal Proteins; D014498:Uracil; D004247:DNA; D004258:DNA Polymerase III; D004259:DNA-Directed DNA Polymerase