Inhibition of RecQ Helicase Activity by Structurally Distinct DNA Lesions: Structure-Function Relationships.

DNA helicase unwinding activity can be inhibited by small molecules and by covalently bound DNA lesions. Little is known about the relationships between the structural features of DNA lesions and their impact on unwinding rates and processivities. Employing RecQ helicase as a model system, and various conformationally defined DNA lesions, the unwinding rate constants = , and processivities = (k) were determined ( unwinding rate constant; , helicase-DNA dissociation rate constant).