S. S. Tavale, H. M. Sobell
Feb 28, 1970
Citations
1
Influential Citations
170
Citations
Quality indicators
Journal
Journal of molecular biology
Abstract
Abstract The crystal structures of 8-bromoguanosine-2H 2 O and 8-bromoadenosine have been determined by X-ray analysis. Both compounds have been found to exist in the syn conformation, in contrast to the more usual anti conformation found in purine nucleosides. It is suggested that this rotational isomerism specifically reflects close contacts introduced by the bromine atom at the 8-position on these purine nucleosides. The significance of these findings is discussed in relation to recent data indicating the inability of the Qβ replicase and the Escherichia coli transcriptase to use 8-substituted purine nucleoside triphosphates as substrates for the RNA polymerization reaction.