Characterization of a Bacillus subtilis 64-kDa DNA Polymerase X Potentially Involved in DNA Repair

• Published in: Journal of molecular biology Vol. 384; no. 5; pp. 1019 - 1028
• Main Authors: Baños, Benito, Lázaro, José M., Villar, Laurentino, Salas, Margarita, de Vega, Miguel
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 31.12.2008
• Subjects: Amino Acid Sequence; Archaea - enzymology; Bacillus subtilis; Bacillus subtilis - enzymology; DNA polymerase; DNA Polymerase beta - chemistry; DNA Repair; DNA, Bacterial - metabolism; DNA-Directed DNA Polymerase - chemistry; DNA-Directed DNA Polymerase - metabolism; family X; Molecular Sequence Data; Molecular Weight; Nucleotides; Polβ; Sequence Alignment; Substrate Specificity; ORF; dRP; dNMP; Polβ; DNA polymerase; TdT; ddNTP; Bacillus subtilis; HhH; EDTA; PolX; DNA repair; BER; BSA; family X
• ISSN: 0022-2836; 1089-8638
• DOI: 10.1016/j.jmb.2008.09.081

Bacillus subtilis gene yshC encodes a 64-kDa family X DNA polymerase (PolXBs), which contains all the critical residues involved in DNA and nucleotide binding as well as those responsible for catalysis of DNA polymerization, conserved in most family X members. Biochemical analyses of the purified enzyme indicate that PolXBs is a monomeric and strictly template-directed DNA polymerase, preferentially acting on DNA structures containing gaps from one to a few nucleotides and bearing a phosphate group at the 5′ end of the downstream DNA. The fact that PolXBs is able to conduct filling of a single-nucleotide gap, allowing further sealing of the resulting nick by a DNA ligase, points to a putative role in base excision repair during the B. subtilis life cycle.