Single-molecule Forster resonance energy transfer reveals an innate fidelity checkpoint in DNA polymerase I.

ABSTRACT: Enzymatic reactions typically involve complex dynamics during substrate binding, conformational rearrangement, chemistry, and product release. The noncovalent steps provide kinetic checkpoints that contribute to the overall specificity of enzymatic reactions. DNA polymerases perform DNA replication with outstanding fidelity by actively rejecting noncognate nucleotide substrates early in the reaction pathway. Substrates are delivered to the active site by a flexible fingers subdomain of the enzyme, as it converts from an open to a closed conformation. The conformational dynamics of the fingers subdomain might also play a role in nucleotide selection, although the precise role is currently unknown. Using single-molecule Förster resonance energy transfer, we observed individual Escherichia co

SUBMITTER: Berezhna SY 

PROVIDER: S-EPMC3448555 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature