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Title: Molecular Recognition and Stabilization of Iminium Ions inWater

Abstract

No abstract prepared.

Authors:
; ; ; ;
Publication Date:
Research Org.:
Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
Sponsoring Org.:
USDOE Director. Office of Science. Basic EnergySciences
OSTI Identifier:
922719
Report Number(s):
LBNL-62062
Journal ID: ISSN 0002-7863; JACSAT; R&D Project: 402103; BnR: KC0302010; TRN: US200803%%528
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of the American Chemical Society; Journal Volume: 128; Related Information: Journal Publication Date: 2006
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; STABILIZATION; WATER; CHEMISTRY

Citation Formats

Dong, Vy M., Fiedler, Dorothea, Carl, Barbara, Bergman, RobertG., and Raymond, Kenneth N. Molecular Recognition and Stabilization of Iminium Ions inWater. United States: N. p., 2006. Web. doi:10.1021/ja0657915.
Dong, Vy M., Fiedler, Dorothea, Carl, Barbara, Bergman, RobertG., & Raymond, Kenneth N. Molecular Recognition and Stabilization of Iminium Ions inWater. United States. doi:10.1021/ja0657915.
Dong, Vy M., Fiedler, Dorothea, Carl, Barbara, Bergman, RobertG., and Raymond, Kenneth N. Wed . "Molecular Recognition and Stabilization of Iminium Ions inWater". United States. doi:10.1021/ja0657915.
@article{osti_922719,
title = {Molecular Recognition and Stabilization of Iminium Ions inWater},
author = {Dong, Vy M. and Fiedler, Dorothea and Carl, Barbara and Bergman, RobertG. and Raymond, Kenneth N.},
abstractNote = {No abstract prepared.},
doi = {10.1021/ja0657915},
journal = {Journal of the American Chemical Society},
number = ,
volume = 128,
place = {United States},
year = {Wed Dec 27 00:00:00 EST 2006},
month = {Wed Dec 27 00:00:00 EST 2006}
}
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  • Limited chemical bromination of poly(r(C-G)) (32% br/sup 8/G, 26% br/sup 5/C) results in partial modification of guanine C8 and cytosine C5, producing a mixture of A- and Z-RNA forms. The Z conformation in the brominated polynucleotide is stabilized at much lower ionic strength than in the unmodified polynucleotide. Raising the ionic strength to 6 M NaBr or NaClO/sub 4/ results in a transition in Br-poly(r(C-G)) to a Z-RNA (Z/sub R/) conformation as judged by CD spectroscopy. /sup 1/H NMR data demonstrate a 1/1 mixture of A- and Z-RNAs in 110 mM NaBr buffer at 37/sup 0/C. Nuclear Overhauser effect (NOE)more » experiments permit complete assignments of GH8, CH6, CH5, GH1', AND CH1' resonances in both the A- and Z-forms. The NMR results indicate that unbrominated guanine residues undergo transition to the syn conformation (Z-form). Raman scattering data are consistent with a mixture of A- and Z-RNAs in 110 mM NaCl buffer at 37 /sup 0/C. /sup 31/P NMR spectra show six to eight resonances spread over a 1.8 ppm range whose chemical shifts are also consistent with an equilibrium mixture of A- and Z-RNAs. Radioimmunoassay and nitrocellulose filter binding competition experiments were performed to determine the extent of recognition of Br-poly(r(C-G)) by anti-Z-DNA antibodies. Competition RIA experiments verify the presence of a Z-DNA-like determinant in left-handed Br-poly(r(C-G)) at physiological NaCl concentration. In summary, these spectroscopic and immunochemical studies demonstrate that under conditions of conformational stress (i.e., containing brominated nucleosides) left-handed Z-RNA is stable and is specifically recognized by proteins at physiological temperature and ionic strength.« less
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