Real-time single-molecule studies of the motions of DNA polymerase fingers illuminate DNA synthesis mechanisms.

ABSTRACT: DNA polymerases maintain genomic integrity by copying DNA with high fidelity. A conformational change important for fidelity is the motion of the polymerase fingers subdomain from an open to a closed conformation upon binding of a complementary nucleotide. We previously employed intra-protein single-molecule FRET on diffusing molecules to observe fingers conformations in polymerase-DNA complexes. Here, we used the same FRET ruler on surface-immobilized complexes to observe fingers-opening and closing of individual polymerase molecules in real time. Our results revealed the presence of intrinsic dynamics in the binary complex, characterized by slow fingers-closing and fast fingers-opening. When binary complexes were incubated with increasing concentrations of complementary nucleotide, the f

SUBMITTER: Evans GW 

PROVIDER: S-EPMC4499156 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature