Single-Molecule Fluorescence Reveals the Unwinding Stepping Mechanism of Replicative Helicase
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TLDR
A coupling ratio of 1:1 between base pairs unwound and dTTP hydrolysis is suggested, which further support the concept that nucleic acid motors can have a hierarchy of different-sized steps or can accumulate elastic energy before transitioning to a subsequent phase.About:
This article is published in Cell Reports.The article was published on 2014-03-27 and is currently open access. It has received 54 citations till now. The article focuses on the topics: Helicase.read more
Citations
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Open-ringed structure of the Cdt1-Mcm2-7 complex as a precursor of the MCM double hexamer
Yuanliang Zhai,Erchao Cheng,Hao Wu,Ningning Li,Philip Y. K. Yung,Ning Gao,Bik Kwoon Tye,Bik Kwoon Tye +7 more
TL;DR: The intrinsic coiled structures of the precursors provide insights into the DH formation, and suggest a spring-action model for the MCM during the initial origin melting and the subsequent DNA unwinding.
Journal ArticleDOI
Simultaneous Real-Time Imaging of Leading and Lagging Strand Synthesis Reveals the Coordination Dynamics of Single Replisomes
Karl E. Duderstadt,Karl E. Duderstadt,Karl E. Duderstadt,Hylkje Geertsema,Sarah A. Stratmann,Christiaan M. Punter,Arkadiusz W. Kulczyk,Charles C. Richardson,Antoine M. van Oijen,Antoine M. van Oijen +9 more
TL;DR: It is shown that loops in the lagging strand predominantly occur during priming and only infrequently support subsequent Okazaki-fragment synthesis, reconciling divergent models for the regulation of primer synthesis and revealing an underlying plasticity in replisome operation.
Journal ArticleDOI
Single-Molecule Analysis and Engineering of DNA Motors
TL;DR: Techniques such as mutagenesis, chemical modifications, and optogenetics that have been used to re-engineer existing molecular motors to have, for instance, altered speed, processivity, or functionality are reviewed.
Journal ArticleDOI
Mechanical Operation and Intersubunit Coordination of Ring-Shaped Molecular Motors: Insights from Single-Molecule Studies
TL;DR: The various mechanisms by which ring motors convert chemical energy to mechanical force or torque and coordinate the activities of individual subunits that constitute the ring are described.
Journal ArticleDOI
The mechanism of DNA unwinding by the eukaryotic replicative helicase.
TL;DR: A mechanism in which purified recombinant Drosophila melanogaster CMG couples ATP hydrolysis to unwinding by acting as a lazy Brownian ratchet is proposed, providing quantitative understanding of the central process in eukaryotic DNA replication.
References
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The Hexameric Helicase DnaB Adopts a Nonplanar Conformation during Translocation
Ornchuma Itsathitphaisarn,Richard A. Wing,William K. Eliason,William K. Eliason,Jimin Wang,Thomas A. Steitz,Thomas A. Steitz +6 more
TL;DR: A hand-over-hand mechanism in which sequential hydrolysis of NTP causes a sequential 5' to 3' movement of the subunits along the helical axis of the staircase, resulting in the unwinding of two nucleotides per subunit is proposed.
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Structure of Hexameric DnaB Helicase and Its Complex with a Domain of DnaG Primase
TL;DR: The crystal structures of hexameric DnaB and its complex with the helicase binding domain (HBD) of DnaG reveal that within the hexamer the two domains of DNAB pack with strikingly different symmetries to form a distinct two-layered ring structure.
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A Molecular Throttle: The Recombination Hotspot χ Controls DNA Translocation by the RecBCD Helicase
Maria Spies,Piero R. Bianco,Mark S. Dillingham,Naofumi Handa,Ronald J. Baskin,Stephen C. Kowalczykowski +5 more
TL;DR: It is proposed that interaction with chi results in an enzyme in which one of the two motor subunits, likely the RecD motor, is uncoupled from the holoenzyme to produce the slower translocase.
Journal ArticleDOI
A General Model for Nucleic Acid Helicases and Their “Coupling” within Macromolecular Machines
TL;DR: A general framework that can highly processive, efficient, specific for the type (DNA be used to describe the molecular mechanisms whereby or RNA) of ssNA substrate (lattice) to which they bind, ATP-driven helicases separate and rearrange the plementary strands of double helical nucleic acids.
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Single-molecule assay reveals strand switching and enhanced processivity of UvrD
TL;DR: A single-molecule manipulation technique is used to monitor real-time changes in extension of a single, stretched, nicked dsDNA substrate as it is unwound by a single enzyme, and observes a feature not seen in bulk assays: unwinding is preferentially followed by a slow, enzyme-translocation-limited rezipping of the separated strands.