title: The amino acid sequence required for 5' --> 3' exonuclease activity of Bacillus caldotenax DNA polymerase.
abstract: We studied the 5' --> 3' exonuclease activity of Bacillus caldotenax DNA polymerase by site-directed mutagenesis. Among seven mutants constructed, two mutant DNA polymerases with an amino acid substitution of Gly184 --> Asp or Gly192 --> Asp were confirmed to be deficient in this exonuclease. The two positions corresponded to those of the Escherichia coli DNA polymerase I mutants defective in 5' --> 3' exonuclease, polA480ex and polA214. These results provide experimental support for the proposed amino acid sequence essential for the 5' --> 3' exonuclease activity associated with eubacterial polymerase I-like DNA polymerases (family A), including E.coli and Thermus aquaticus.
authors.affiliation: Biotechnology Research Laboratories, Takara Shuzo Co., Ltd., Shiga, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Ishino
authors.forename: A
authors.initials: A
authors.lastname: Takahashi-Fujii
authors.forename: T
authors.initials: T
authors.lastname: Uemori
authors.forename: M
authors.initials: M
authors.lastname: Imamura
authors.forename: I
authors.initials: I
authors.lastname: Kato
authors.forename: H
authors.initials: H
authors.lastname: Doi
mesh_terms: D001407:Bacillus / Q000201:enzymology* / Q000235:genetics; D001483:Base Sequence; D004256:DNA Polymerase I / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics; D043211:Exodeoxyribonuclease V; D005090:Exodeoxyribonucleases / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D011994:Recombinant Proteins / Q000378:metabolism; D013329:Structure-Activity Relationship
chemical_list: D011994:Recombinant Proteins; D004256:DNA Polymerase I; D005090:Exodeoxyribonucleases; D043211:Exodeoxyribonuclease V