Calcium-driven DNA synthesis by a high-fidelity DNA polymerase.

ABSTRACT: Divalent metal ions, usually Mg2+, are required for both DNA synthesis and proofreading functions by DNA polymerases (DNA Pol). Although used as a non-reactive cofactor substitute for binding and crystallographic studies, Ca2+ supports DNA polymerization by only one DNA Pol, Dpo4. Here, we explore whether Ca2+-driven catalysis might apply to high-fidelity (HiFi) family B DNA Pols. The consequences of replacing Mg2+ by Ca2+ on base pairing at the polymerase active site as well as the editing of terminal nucleotides at the exonuclease active site of the archaeal Pyrococcus abyssi DNA Pol (PabPolB) are characterized and compared to other (families B, A, Y, X, D) DNA Pols. Based on primer extension assays, steady-state kinetics and ion-chased experiments, we demonstrate that Ca2+ (and other me

SUBMITTER: Ralec C 

PROVIDER: S-EPMC5716173 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature