Linked Life Data

8300610

Source:http://linkedlifedata.com/resource/pubmed/id/8300610

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1994-3-4
pubmed:abstractText
The functional role of Zn(II) binding by T4 gene 32 protein (gp32), a single-stranded DNA-binding protein, has been investigated by assessing the capacity of a well-characterized metal-free gp32 derivative to function in vitro as an accessory protein of T4 uvsX-catalyzed homologous pairing. Metal-free gp32 was prepared upon reaction of cysteine thiolates with methylmethanethiol-sulfonate to form the mixed disulfide Cys-SSCH3 or S-methylated species. Far and near ultraviolet circular dichroism spectroscopy suggest a moderate but easily detected change in the far UV region, accompanied by only a minor alteration in the near UV region, relative to the Zn(II)-containing protein. Restoration of the wild-type spectral features is accomplished upon the addition of 2 mM dithiothreitol and excess Zn(II) but not dithiothreitol alone. Unlike wild-type gp32, apo S-methylated gp32 shows weak binding to the recombination substrate, single-stranded M13mp19, and fails to stimulate homologous pairing with a linear M13mp19 duplex substrate by uvsX protein. Complete reactivation of the apo S-methylated protein as a recombination-accessory protein is achievable in situ in the presence of reducing agent and sufficient exogenous Zn(II), but not one or the other alone. Analogous results are obtained with S-methylated C166S (Cys166-->Ser) gp32, revealing that only the metal-liganding cysteines participate in the reconstitution. These findings suggest that formation of the Zn(II) chelate is directly linked to single-stranded DNA binding and functional efficacy of gp32 in DNA metabolism.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
28
pubmed:volume
269
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2773-81
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:8300610-Apoproteins, pubmed-meshheading:8300610-Binding Sites, pubmed-meshheading:8300610-Circular Dichroism, pubmed-meshheading:8300610-Cysteine, pubmed-meshheading:8300610-DNA, Single-Stranded, pubmed-meshheading:8300610-DNA-Binding Proteins, pubmed-meshheading:8300610-Dithionitrobenzoic Acid, pubmed-meshheading:8300610-Dithiothreitol, pubmed-meshheading:8300610-Edetic Acid, pubmed-meshheading:8300610-Methylation, pubmed-meshheading:8300610-Oxidation-Reduction, pubmed-meshheading:8300610-Protein Binding, pubmed-meshheading:8300610-Protein Conformation, pubmed-meshheading:8300610-Recombinant Proteins, pubmed-meshheading:8300610-Recombination, Genetic, pubmed-meshheading:8300610-Structure-Activity Relationship, pubmed-meshheading:8300610-Viral Proteins, pubmed-meshheading:8300610-Zinc
pubmed:year
1994
pubmed:articleTitle
Zinc-free and reduced T4 gene 32 protein binds single-stranded DNA weakly and fails to stimulate UvsX-catalyzed homologous pairing.
pubmed:affiliation
Department of Biochemistry and Biophysics, Texas A & M University, College Station 77843-2128.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't