On the mechanism of ribonucleoside diphosphate reductase from Escherichia coli. Evidence for 3'-C--H bond cleavage

Abstract

The 3'-carbon--hydrogen bond of [3'-3H]uridine 5'-diphosphate is cleaved during its conversion to 2'-deoxyuridine 5'-diphosphate catalyzed by Esherichia coli ribonucleoside diphosphate reductase. A selection against 3H of approximately 3.3 is observed on this reduction reaction. During the course of this reaction, a small but significant amount of 3H is released to the solvent.