期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1977
卷号：74
期号：11
页码：4872-4875
DOI：10.1073/pnas.74.11.4872
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The interaction of carboxylate ions (acetate, butyrate) with nucleic aicd bases and nucleosides has been investigated by proton magnetic resonance in dimethyl sulfoxide (d6)/H2O mixtures. Carboxylate ions interacted only with guanine derivatives and led to a large downfield shift of the NH2 resonance. A 1:1 stoichiometry was deduced from a study of the concentration dependence of chemical shifts. A study of substituted guanine showed that hydrogen bonding involved N(1)H and NH2(2). An association constant of 110 M-1 was determined. This value is about 30 times higher than the association constant for guanine-cytosine base pair formation under the same experimental conditions. As a matter of fact, carboxylate ions induced a dissociation of guanine-cytosine base pairs. This guanine-carboxylate association is experimental evidence for a highly specific interaction that could play an important role in protein/nucleic acid recognition.
