Linked Life Data

6254972

Source:http://linkedlifedata.com/resource/pubmed/id/6254972

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
23
pubmed:dateCreated
1981-2-19
pubmed:abstractText
It has been shown previously (Polisky, B., Green, P., Garfin, D. E., McCarthy, B. J., Goodman, H. M., and Boyer, H. W. (1975) Proc. Natl. Acad. Sci. U. S. A. 72, 3310-3314; Hsu, M., and Berg, P. (1978) Biochemistry 17, 131-138) that the cleavage sequence specificity of Eco RI endonuclease can be "relaxed" by various means. In this paper this phenomenon is explored in detail, in order to obtain further insight into the nature and selectivity of sequence recognition patterns between proteins and double-stranded nucleic acids. Using conditions of low ionic strength and alkaline pH, we have mapped the positions of potentially cleavable sites in the (completely sequenced) replicative form of the bacteriophage phi X174 genome, and have deduced their sequence. The time course of digestion of phi X174 DNA suggests that double-stranded sequences reading GGATTT, AAATTT, GAATTT, and GAATTA (only "top" strands, written 5' leads to 3', are shown) are cleaved readily under these conditions, while sequences reading CAATTN (N = A, T, G) resist attack. Cleavages at (at least) the more labile sites result in cohesive ends that are religatable. End group analysis of cleaved phi X174 DNA fragments indicates the presence of a 5'-terminal adenine residue on most of the fragments; some fragments may carry a 5'-terminal guanine residue, consistent with the cleavage site sequences suggested above. Addition of Mn2+ to cleavage reactions carried out at moderate salt concentrations and near-neutral pH induces the same pattern of cleavage seen at low ionic strength and alkaline pH. These results are combined with those from other studies, and are interpreted in terms of a model for the site-specific interaction of the Eco RI endonuclease with its substrate, considering both the effects of changes in DNA sequence and of environmental alterations. The resulting model is compared with data developed on similar grounds for Eco RI methylase (see Woodbury, C. P., Downey, R. L., and von Hippel, P. H. (1980) J. Biol. Chem. 255, 11526-11533), and attempts are made to define both common and differing molecular facets of the DNA recognition specificity of these companion (but genetically distinct) enzymes.
pubmed:grant
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
255
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11534-48
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1980
pubmed:articleTitle
DNA site recognition and reduced specificity of the Eco RI endonuclease.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.