Bypass of N²-ethylguanine by human DNA polymerase κ.

ABSTRACT: The efficiency and fidelity of nucleotide incorporation and next-base extension by DNA polymerase (pol) κ past N(2)-ethyl-Gua were measured using steady-state and rapid kinetic analyses. DNA pol κ incorporated nucleotides and extended 3' termini opposite N(2)-ethyl-Gua with measured efficiencies and fidelities similar to that opposite Gua indicating a role for DNA pol κ at the insertion and extension steps of N(2)-ethyl-Gua bypass. The DNA pol κ was maximally activated to similar levels by a twenty-fold lower concentration of Mn(2+) compared to Mg(2+). In addition, the steady state analysis indicated that high fidelity DNA pol κ-catalyzed N(2)-ethyl-Gua bypass is Mg(2+)-dependent. Strikingly, Mn(2+) activation of DNA pol κ resulted in a dramatically lower efficiency of correct nucleotide i

SUBMITTER: Pence MG 

PROVIDER: S-EPMC3010520 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature