| Literature DB >> 20060554 |
Krishanu Ray1, Chandran R Sabanayagam, Joseph R Lakowicz, Lindsay W Black.
Abstract
Many large double-stranded DNA viruses employ high force-generating ATP-driven molecular motors to package to high density their genomes into empty procapsids. Bacteriophage T4 DNA translocation is driven by a two-component motor consisting of the procapsid portal docked with a packaging terminase-ATPase. Fluorescence resonance energy transfer and fluorescence correlation spectroscopic (FRET-FCS) studies of a branched (Y-junction) DNA substrate with a procapsid-anchoring leader segment and a single dye molecule situated at the junction point reveal that the "Y-DNA" stalls in proximity to the procapsid portal fused to GFP. Comparable structure Y-DNA substrates containing energy transfer dye pairs in the Y-stem separated by 10 or 14 base pairs reveal that B-form DNA is locally compressed 22-24% by the linear force of the packaging motor. Torsional compression of duplex DNA is thus implicated in the mechanism of DNA translocation. Copyright 2009 Elsevier Inc. All rights reserved.Entities:
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Year: 2010 PMID： 20060554 PMCID： PMC2824061 DOI： 10.1016/j.virol.2009.11.047
Source DB: PubMed Journal: Virology ISSN： 0042-6822 Impact factor: 3.616