Linked Life Data

1736306

Source:http://linkedlifedata.com/resource/pubmed/id/1736306

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1992-3-10
pubmed:abstractText
The importance of the 2'-hydroxyl group of several guanosine residues for the catalytic efficiency of a hammerhead ribozyme has been investigated. Five ribozymes in which single guanosine residues were substituted with 2'-amino-, 2'-fluoro-, or 2'-deoxyguanosine were chemically synthesized. The comparison of the catalytic activity of the three 2' modifications at a specific position allows conclusions about the functional role of the parent 2'-hydroxyl group. Substitutions of nonconserved nucleotides within the ribozyme caused little alteration in the catalytic activity relative to that obtained with the unmodified ribozyme. In contrast, when either of the guanosines within the single-stranded loop between stem I and stem II of the ribozyme was replaced by 2'-deoxyguanosine or 2'-fluoro-2'-deoxyguanosine, the catalytic activities of the resulting ribozymes were reduced by factors of at least 150. The catalytic activities of the corresponding ribozymes containing 2'-amino-2'-deoxyguanosine substitutions at these positions, however, were both reduced by factors of 15. These effects resulted from decreases in the respective kcat values, whereas variations in the Km values were comparatively small. A different pattern of reactivity of the three 2' modifications was observed at the guanosine immediately 3' to stem II of the ribozyme. Whereas both 2'-deoxyguanosine and 2'-amino-2'-deoxyguanosine at this position showed catalytic activity similar to that of the unmodified ribozyme, the activity of the corresponding 2'-fluoro-2'-deoxyguanosine-containing ribozyme was reduced by a factor of 15. The implications of these substitution-specific reactivities on the functional role of the native 2'-hydroxyl groups are discussed.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/1736306-1689847, http://linkedlifedata.com/resource/pubmed/commentcorrection/1736306-1692411, http://linkedlifedata.com/resource/pubmed/commentcorrection/1736306-1703005, http://linkedlifedata.com/resource/pubmed/commentcorrection/1736306-1708285, http://linkedlifedata.com/resource/pubmed/commentcorrection/1736306-1709484, http://linkedlifedata.com/resource/pubmed/commentcorrection/1736306-1857967, http://linkedlifedata.com/resource/pubmed/commentcorrection/1736306-1911762, http://linkedlifedata.com/resource/pubmed/commentcorrection/1736306-2018768, http://linkedlifedata.com/resource/pubmed/commentcorrection/1736306-2181322, http://linkedlifedata.com/resource/pubmed/commentcorrection/1736306-2402441, http://linkedlifedata.com/resource/pubmed/commentcorrection/1736306-2441261, http://linkedlifedata.com/resource/pubmed/commentcorrection/1736306-2457170, http://linkedlifedata.com/resource/pubmed/commentcorrection/1736306-2696172, http://linkedlifedata.com/resource/pubmed/commentcorrection/1736306-4366081, http://linkedlifedata.com/resource/pubmed/commentcorrection/1736306-5545352, http://linkedlifedata.com/resource/pubmed/commentcorrection/1736306-7433125
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0027-8424
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
89
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
918-21
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Function of specific 2'-hydroxyl groups of guanosines in a hammerhead ribozyme probed by 2' modifications.
pubmed:affiliation
Max-Planck-Institut für Experimentelle Medizin, Abteilung Chemie, Göttingen, Federal Republic of Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't