Linked Life Data

200616

Source:http://linkedlifedata.com/resource/pubmed/id/200616

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
23
pubmed:dateCreated
1978-1-27
pubmed:abstractText
A homogeneous preparation of venom phosphodiesterase from Crotalus adamanteus possesses an intrinsic endonuclease activity, specific for superhelical (form I) and single-stranded DNA. The phosphodiesterase degrades single-stranded T7 DNA by endonucleolytic cleavages. Duplex T7 DNA is hydrolyzed by the liberation of acid-soluble products simultaneously from the 3' and 5' termini but without demonstrable internal scissions in duplex regions. Since venom phosphodiesterase is known to hydrolyze oligonucleotides stepwise from the 3' termini, the cleavage at the 5' end of duplex T7 DNA is ascribed to an endonuclease activity. Form I PM2 DNA is nicked to yield first relaxed circles and then linear DNA which is subsequently hydrolyzed only from the chain termini. The linear duplex DNA intermediates consist of a discrete series of fragments (11 are usually resolved on agarose gels) with initial molecular weights ranging from 6.3 x 10(6) (the intact PM2 DNA size) to approximately 1 x 10(6). The cleavage of the form I molecule must, therefore, occur at a limited number of unique sites. The enzyme also cleaves nonsuperhelical, covalently closed circular PM2 DNA but at a 10(4) times slower rate. Both the endonuclease activity on form I DNA and the known exonuclease activity co-migrate on polyacrtkanude gels, are optimally active at pH 9, are stimulated by small concentrations of Mg2+, and are similarly inactivated by heat, reducing agents, and EDTA.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
10
pubmed:volume
252
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
8652-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1977
pubmed:articleTitle
An endonuclease activity of venom phosphodiesterase specific for single-stranded and superhelical DNA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.