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dc.contributor.authorTomko, Eric J.
dc.contributor.authorFischer, Christopher J.
dc.contributor.authorLohman, Timothy M.
dc.date.accessioned2017-03-27T21:05:41Z
dc.date.available2017-03-27T21:05:41Z
dc.date.issued2012-02-14
dc.identifier.citationTomko, Eric J., Christopher J. Fischer, and Timothy M. Lohman. "Single-Stranded DNA Translocation of E. Coli UvrD Monomer Is Tightly Coupled to ATP Hydrolysis." Journal of Molecular Biology 418.1-2 (2012): 32-46.en_US
dc.identifier.urihttp://hdl.handle.net/1808/23492
dc.description.abstractE. coli UvrD is an SF1A helicase/translocase that functions in several DNA repair pathways. A UvrD monomer is a rapid and processive single-stranded (ss) DNA translocase, but is unable to unwind DNA processively in vitro. Based on data at saturating ATP (500 μM) we proposed a non-uniform stepping mechanism in which a UvrD monomer translocates with biased (3′ to 5′) directionality while hydrolyzing 1 ATP per DNA base translocated, but with a kinetic step-size of 4–5 nucleotides/step, suggesting a pause occurs every 4–5 nucleotides translocated. To further test this mechanism we examined UvrD translocation over a range of lower ATP concentrations (10–500 μM ATP), using transient kinetic approaches. We find a constant ATP coupling stoichiometry of ~1 ATP/DNA base translocated even at the lowest ATP concentration examined (10 μM) indicating that ATP hydrolysis is tightly coupled to forward translocation of a UvrD monomer along ssDNA with little slippage or futile ATP hydrolysis during translocation. The translocation kinetic step size remains constant at 4–5 nucleotides/step down to 50 μM ATP, but increases to ~7 nucleotides/step at 10 μM ATP. These results suggest that UvrD pauses more frequently during translocation at low ATP, but with little futile ATP hydrolysis.en_US
dc.publisherElsevieren_US
dc.rightsThis is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License 3.0 (CC BY-NC-ND 3.0 US), which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.en_US
dc.subjectHelicaseen_US
dc.subjectMotor proteinen_US
dc.subjectTranslocaseen_US
dc.subjectKinetic step sizeen_US
dc.subjectATP coupling stoichiometryen_US
dc.titleSingle stranded DNA translocation of E. coli UvrD monomer is tightly coupled to ATP hydrolysisen_US
dc.typeArticleen_US
kusw.kuauthorFischer, Christopher J.
kusw.kudepartmentPhysics and Astronomyen_US
dc.identifier.doi10.1016/j.jmb.2012.02.013en_US
kusw.oaversionScholarly/refereed, author accepted manuscripten_US
kusw.oapolicyThis item meets KU Open Access policy criteria.en_US
dc.rights.accessrightsopenAccess


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