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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
2
|
| pubmed:dateCreated |
1997-7-11
|
| pubmed:abstractText |
The effects of 2'-substituents of the first deoxyguanosine on EcoRI activity were examined using synthetic octadeoxynucleotides D(GG*AATTCC) containing 2'-substituted derivatives (G*), i.e., 2'-fluoro-2'-deoxyguanosine (dGfl), 2'-chloro-2'-deoxyguanosine (dGcl), and guanosine (rG). The overall structures of the octamers were very similar, as shown by CD and UV measurements, although their EcoRI reactivities were very different: 100% in 60 min for d(GGAATTCC) and d(GGflAATTCC), 5% in 24 h for d[G(rG)AATTCC], and no cleavage at all in 24 h for d(GGclAATTCC). However, the kinetics showed the octamers exhibit similar binding-affinity to the enzyme (10(-6)-10(-7) M). 31P-NMR analysis suggested the modified octamers change the phosphate backbone conformation in a duplex, since an unusual downfield-shifted signal in the spectra was commonly observed for the modified octamers at low temperature (i.e., a duplex state), which was shifted upfield at high temperature (i.e., a single strand state). The order of the differences was dGcl > rG > dGfl-containing octamers, coinciding with that of the vdW volume of 2'-substituents (Cl > OH > F) and the cleavage reactivities. These findings suggest that steric hindrance by the 2'-substituents causes of conformational change of the phosphate backbone close to the scissile bond, and then interferes with the EcoRI reaction.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:month |
Feb
|
| pubmed:issn |
0021-924X
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| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
121
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
219-24
|
| pubmed:dateRevised |
2007-12-19
|
| pubmed:meshHeading |
pubmed-meshheading:9089393-Binding Sites,
pubmed-meshheading:9089393-Catalysis,
pubmed-meshheading:9089393-Circular Dichroism,
pubmed-meshheading:9089393-Deoxyguanosine,
pubmed-meshheading:9089393-Deoxyribonuclease EcoRI,
pubmed-meshheading:9089393-Kinetics,
pubmed-meshheading:9089393-Magnetic Resonance Spectroscopy,
pubmed-meshheading:9089393-Models, Chemical,
pubmed-meshheading:9089393-Stereoisomerism,
pubmed-meshheading:9089393-Structure-Activity Relationship,
pubmed-meshheading:9089393-Substrate Specificity
|
| pubmed:year |
1997
|
| pubmed:articleTitle |
Effects of 2'-substituents of the first deoxyguanosine residue in the recognition sequence of EcoRI restriction endonuclease activity.
|
| pubmed:affiliation |
Faculty of Pharmaceutical Sciences, Osaka University.
|
| pubmed:publicationType |
Journal Article
|