Uracil in deoxyribonucleotide polymers reduces their template-primer activity for E. coli DNA polymerase I

Nucleic Acids Res. 1983 Jun 11;11(11):3753-65. doi: 10.1093/nar/11.11.3753.

Abstract

The physical and biochemical properties of two pairs of synthetic DNA template-primers were investigated. The copolymer poly(dA-dU) . poly(dA-dU) and the homopolymer duplex poly(dA). poly(dU) were characterized by a lower Tm and by a higher buoyant density value than the respective thymine polynucleotides poly(dA-dT) . poly(dA-dT) and poly(dA) . poly(dT). The polymerizing and the primer terminus adding reactions of a homogenous E. coli DNA polymerase I preparation, as measured by incorporation of [3H]dAMP into the acid-insoluble fraction, were significantly poorer with uracil-containing template-primers than with thymine templates. Moreover, the uracil-containing polynucleotides inhibited the polymerizing activity of DNA polymerase I to a greater extent than the thymine polynucleotides, when the enzymatic activity was investigated with a dATP/dTTP/dUTP-free incorporation system making use of poly(dI-dC) . poly(dI-dC) as the template-primer.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA Polymerase I / metabolism*
  • DNA-Directed DNA Polymerase / metabolism*
  • Deoxyribonucleotides
  • Escherichia coli / enzymology*
  • Kinetics
  • Poly A
  • Poly A-U
  • Poly dA-dT / analogs & derivatives
  • Polydeoxyribonucleotides*
  • Structure-Activity Relationship
  • Templates, Genetic

Substances

  • Deoxyribonucleotides
  • Polydeoxyribonucleotides
  • Poly A-U
  • Poly A
  • poly(dA)
  • Poly dA-dT
  • poly(d(A-U))
  • DNA Polymerase I
  • DNA-Directed DNA Polymerase