C O M M U N I C A T I O N S
k
cat of ∼9 × 10-3 ( 7 × 10-4 min-1 (kcat ) V/ET taken at 3, 5, 10,
References
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a small amount RNaseA could have contaminated the purification
of 1 (data in Supporting Information).23
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Directed synthesis to append imidazoles or amines or both to
oligonucleotides so as to target RNA cleavage represents an exciting
avenue of research. Nevertheless, single-turnover cleavage, if
observed at all, is often significantly slower than that observed for
1, whereas multiple turnover, to the best of our knowledge, has
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are involved directly in catalysis rather than simply in folding and
pKa perturbation of C or G will be of paramount importance to
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Acknowledgment. This work is dedicated to the memory of
David S. Sigman (1939-2001). Y.R. was awarded a PDF by “le
Programme Lavoisier du Ministe`re des Affaires Etrange`res”
(France). This work was supported by UBC start-up funds and
NSERC (Natl. Sci. Eng. Res. Council) of Canada.
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Supporting Information Available: Experimental details (PDF).
This material is available free of charge via the Internet at http://
pubs.acs.org.
J. A.; Williams, D. M. Nucleic Acids Res. 2001, 29, 1898.
JA0205075
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