DNA is bound within the central hole to one or two of the six subunits of the T7 DNA helicase
Nature Structural & Molecular BiologyPublished 1 September 1996
Xiong Yu, Manju Hingorani, Smita S. Patel, Edward H. Egelman
Citations111
SJR quartileQ1
SJR score6.19
SNIP2.06
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TL;DR
Electron microscopic image analysis and protein–DNA crosslinking show that DNA binds asymmetrically to the hexameric bacteriophage T7 gp4b helicase, and binds to only one or two subunits.
Abstract
Electron microscopic image analysis and protein–DNA crosslinking show that DNA binds asymmetrically to the hexameric bacteriophage T7 gp4b helicase, and binds to only one or two subunits
Keywords
Biochemistry, Genetics and Molecular BiologyEnvironmental Science
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The similarity in three-dimensional structure of the T7 gene 4 proteins to that of the Escherichia coli RuvB helicase suggests that polar rings assembled around DNA may be a general feature of numerous hexameric helicases involved in DNA replication, transcription, recombination, and repair.
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It is directly shown that the helicase activity of the gene 4 protein is also profoundly inhibited by the benzo[a]pyrene-DNA adducts, which are strand-specific and block the DNA helicase activities of the genes 4 protein only when they are located in the DNA strand where the gene4 protein translocates when it unwinds double-stranded DNA.
