The RB69 DNA polymerase binding-pocket residue Tyr567 was shown previously to be a key determinant of fidelity because the replacement Y567A causes a powerful mutator activity. Ser565 is a nearby component of the binding pocket. Unlike Y567A, the replacement S565G has only a small impact on fidelity. However, combining Y567A and S565G reverses most of the mutator activity of Y567A. This is a unique and instructive observation in structural studies of polymerase fidelity, and we are working through a detailed examination of the mutational propensities of these constructs both in vivo and in vitro.

Project Start
Project End
Budget Start
Budget End
Support Year
12
Fiscal Year
2009
Total Cost
$14,169
Indirect Cost
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Trzemecka, Anna; Jacewicz, Agata; Carver, Geraldine T et al. (2010) Reversal of a mutator activity by a nearby fidelity-neutral substitution in the RB69 DNA polymerase binding pocket. J Mol Biol 404:778-93
Drake, John W (2009) Avoiding dangerous missense: thermophiles display especially low mutation rates. PLoS Genet 5:e1000520