Nucleotide sequence of the Escherichia coli polA gene and primary structure of DNA polymerase I

J Biol Chem. 1982 Feb 25;257(4):1958-64.


We report the nucleotide sequence of 3.2 kilobase pair region of the Escherichia coli polA gene, comprising the coding region for DNA polymerase I with about 400 base pairs of flanking sequence. The amino acid sequence for DNA polymerase I derived from our DNA sequence is largely consistent with previous protein chemical data. In the following paper, Brown et al. (Brown, W. E., Stump, K. H., and Kelley, W. S. (1982) J. Biol. Chem. 257, 1965-1972) present additional protein chemistry experiments that further confirm our sequence. Mild proteolysis of DNA polymerase I is known to produce two enzymatically active fragments (Brutlag, D., Atkinson, M. R., Setlow, P., and Kornberg, A. (1969) Biochem. Biophys. Res. Commun. 37, 982-989; Klenow, H., and Henningsen, I. (1970) Proc. Natl. Acad. Sci. U. S. A. 74, 5632-5636). We have located the site of this cleavage between residues 323 and 324 of the 928 amino acid polymerase molecule. By sequence comparison of the polA1 and wild type alleles, we have identified the polA1 mutation as a change from Trp (TGG) to amber (TAG) at residue 342.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • DNA Restriction Enzymes
  • Escherichia coli / enzymology*
  • Escherichia coli / genetics
  • Genes*
  • Peptide Fragments / analysis
  • Plasmids


  • Peptide Fragments
  • DNA Restriction Enzymes

Associated data

  • GENBANK/J01663
  • GENBANK/J01703
  • GENBANK/M20780