Cloning, purification, and characterization of a new DNA polymerase from a hyperthermophilic archaeon, Thermococcus sp. NA1

J Microbiol Biotechnol. 2007 Jul;17(7):1090-7.

Abstract

Genomic analysis of Thermococcus sp. NA revealed the presence of a 3,927-base-pair (bp) family B-type DNA polymerase gene, TNA1_pol. TNA1_pol, without its intein, was overexpressed in Escherichia coli, purified using metal affinity chromatography, and characterized. TNA1_pol activity was optimal at pH 7.5 and 75 degrees C. TNA1_pol was highly thermostable, with a half-life of 3.5 h at 100 degrees C and 12.5 h at 95 degrees C. Polymerase chain reaction parameters of TNA1_pol such as error-rate, processivity, and extension rate were measured in comparison with rTaq, Pfu, and KOD DNA polymerases. TNA1_pol averaged one incorrect bp every 4.45 kilobases (kb), and had a processivity of 150 nucleotides (nt) and an extension rate of 60 bases/s. Thus, TNA1_pol has a much faster elongation rate than Pfu DNA polymerase with 7-fold higher fidelity than that of rTaq.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Motifs
  • Amino Acid Sequence
  • Archaea / enzymology*
  • Archaeal Proteins / chemistry
  • Archaeal Proteins / genetics
  • Archaeal Proteins / metabolism
  • Base Sequence
  • Cloning, Molecular
  • DNA Primers / chemistry
  • DNA Primers / metabolism
  • DNA, Bacterial / genetics
  • DNA, Bacterial / isolation & purification
  • DNA-Directed DNA Polymerase / analysis
  • DNA-Directed DNA Polymerase / chemistry
  • DNA-Directed DNA Polymerase / genetics*
  • DNA-Directed DNA Polymerase / isolation & purification*
  • Enzyme Stability
  • Escherichia coli / genetics
  • Genes, Bacterial
  • Half-Life
  • Hydrogen-Ion Concentration
  • Molecular Sequence Data
  • Molecular Weight
  • Open Reading Frames
  • Polymerase Chain Reaction
  • Protein Structure, Tertiary
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / metabolism
  • Sequence Analysis, DNA
  • Temperature
  • Thermococcus / enzymology*
  • Thermococcus / genetics

Substances

  • Archaeal Proteins
  • DNA Primers
  • DNA, Bacterial
  • Recombinant Proteins
  • DNA-Directed DNA Polymerase