Publication Date:
1991-07-19
Description:
The incorporation of 2'-fluoro- and 2'-aminonucleotides into a hammerhead ribozyme was accomplished by automated chemical synthesis. The presence of 2'-fluorouridines, 2'-fluorocytidines, or 2'-aminouridines did not appreciably decrease catalytic efficiency. Incorporation of 2'-aminocytidines decreased ribozyme activity approximately by a factor of 20. The replacement of all adenosines with 2'-fluoroadenosines abolished catalysis in the presence of MgCl2 within the limits of detection, but some activity was retained in the presence of MnCl2. This effect on catalysis was localized to a specific group of adenines within the conserved single-stranded region of the ribozyme. The decrease in catalytic efficiency was caused by a decrease in the rate constant; the Michaelis constant was unaltered. The 2'-fluoro and 2'-amino modifications conferred resistance toward ribonuclease degradation. Ribozymes containing 2'-fluoro- or 2'-aminonucleotides at all uridine and cytidine positions were stabilized against degradation in rabbit serum by a factor of at least 10(3) compared to unmodified ribozyme.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Pieken, W A -- Olsen, D B -- Benseler, F -- Aurup, H -- Eckstein, F -- New York, N.Y. -- Science. 1991 Jul 19;253(5017):314-7.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Max-Planck-Institut fur Experimentelle Medizin, Abteilung Chemie, Gottingen, Federal Republic of Germany.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/1857967" target="_blank"〉PubMed〈/a〉
Keywords:
Base Sequence
;
*Chlorides
;
Kinetics
;
Magnesium Chloride/pharmacology
;
Manganese/pharmacology
;
*Manganese Compounds
;
Molecular Sequence Data
;
Nucleic Acid Conformation
;
RNA, Catalytic/chemical synthesis/*metabolism
;
Ribonucleases/*metabolism
;
Ribonucleotides
;
Substrate Specificity
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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