The class I E. coli ribonucleotide reductase, composed of homodimers of R1 and R2, catalyzes the conversion of nucleoside diphosphates to deoxynucleoside diphosphates. The reduction process involves the tyrosyl radical on R2 that generates a transient thiyl radical on R1 over a proposed distance of 35 A. A mechanism-based inhibitor, 2'-azido-2'-deoxyuridine-5'-diphosphate, that reduces the tyro...
