1kfd
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CRYSTAL STRUCTURES OF THE KLENOW FRAGMENT OF DNA POLYMERASE I COMPLEXED WITH DEOXYNUCLEOSIDE TRIPHOSPHATE AND PYROPHOSPHATE
OverviewOverview
Crystal structures of the Klenow fragment (KF) of DNA polymerase I from, Escherichia coli complexed with deoxynucleoside triphosphate (dNTP) or, with pyrophosphate (PPi) determined to 3.9-A resolution by X-ray, crystallography show these molecules binding within the cleft of the, polymerase domain and surrounded by residues previously implicated in dNTP, binding. The dNTP binds adjacent to the O-helix [Ollis, D. L., Brick, P., Hamlin, R., Xuong, N. G., & Steitz, T. A. (1985a) Nature 313, 762-766], with its triphosphate moiety anchored by three positively charged, residues, Arg 754, Arg 682, and Lys 758, plus His 734 and Gln 708. The, dNTP binding site observed in the crystal is consistent with the results, of chemical modification including cross-linking and is also near many of, the amino acid residues whose mutation affects catalysis [Polesky, A. H., Steitz, T. A., Grindley, N. D. F., & Joyce, C. M. (1990) J. Biol. Chem., 265, 14579-14591; Polesky, A. H., Dahlberg, M. E., Benkovic, S. J., Grindley, N. D. F., & Joyce, C. M. (1992) J. Biol. Chem. 267, 8417-8428]., However, we conclude that the position of at least the dNMP moiety of dNTP, in the binary complex is not likely to be the same as in its catalytically, relevant complex with primer-template DNA.
About this StructureAbout this Structure
1KFD is a Single protein structure of sequence from Escherichia coli with CTP as ligand. Active as DNA-directed DNA polymerase, with EC number 2.7.7.7 Full crystallographic information is available from OCA.
ReferenceReference
Crystal structures of the Klenow fragment of DNA polymerase I complexed with deoxynucleoside triphosphate and pyrophosphate., Beese LS, Friedman JM, Steitz TA, Biochemistry. 1993 Dec 28;32(51):14095-101. PMID:8260491
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