Re-evaluating the kinetics of ATP hydrolysis during initiation of DNA sliding by Type III restriction enzymes.

ABSTRACT: DNA cleavage by the Type III restriction enzymes requires long-range protein communication between recognition sites facilitated by thermally-driven 1D diffusion. This 'DNA sliding' is initiated by hydrolysis of multiple ATPs catalysed by a helicase-like domain. Two distinct ATPase phases were observed using short oligoduplex substrates; the rapid consumption of ∼10 ATPs coupled to a protein conformation switch followed by a slower phase, the duration of which was dictated by the rate of dissociation from the recognition site. Here, we show that the second ATPase phase is both variable and only observable when DNA ends are proximal to the recognition site. On DNA with sites more distant from the ends, a single ATPase phase coupled to the conformation switch was observed and subsequent site

SUBMITTER: Toth J 

PROVIDER: S-EPMC4678819 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature