Linked Life Data

1627551

Source:http://linkedlifedata.com/resource/pubmed/id/1627551

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
26
pubmed:dateCreated
1992-8-18
pubmed:abstractText
In the absence of magnesium ions, the EcoRV restriction endonuclease binds all DNA sequences with equal affinity but cannot cleave DNA. In the presence of Mg2+, the EcoRV endonuclease cleaves DNA at one particular sequence, GATATC, at least a million times more readily than any other sequence. To elucidate the role of the metal ion, the reactions of the EcoRV restriction enzyme were studied in the presence of MnCl2 instead of MgCl2. The reaction at the EcoRV recognition site was slower with Mn2+. This was caused partly by reduced rates for phosphodiester hydrolysis but also by the translocation of the enzyme along the DNA after cleaving it in one strand. In contrast, alternative sites that differ from the recognition site by one base pair were cleaved faster in the presence of Mn2+ relative to Mg2+. When located at an alternative site on the DNA, the EcoRV enzyme bound Mn2+ ions readily but had a very low affinity for Mg2+. The EcoRV nuclease is thus restrained from cleaving DNA at alternate sites in the presence of Mg2+, but the restraint fails to operate with Mn2+. A discrimination factor, which measures the ratio of the activity of the EcoRV nuclease at its recognition site over that at an alternative site, had values of 3 x 10(5) in MgCl2 and 6 in MnCl2.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
7
pubmed:volume
31
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
6082-9
pubmed:dateRevised
2008-8-29
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
EcoRV restriction endonuclease: communication between catalytic metal ions and DNA recognition.
pubmed:affiliation
Department of Biochemistry, University of Bristol, U.K.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't