The mechanism of the anaerobic Escherichia coli ribonucleotide reductase investigated with nuclear magnetic resonance spectroscopy

Biochem Biophys Res Commun. 1995 Sep 5;214(1):28-35. doi: 10.1006/bbrc.1995.2252.

Abstract

During the reduction of ribonucleotides with [3H]formate by the class III anaerobic ribonucleotide reductase from Escherichia coli tritium appears in water and not in the product deoxyribonucleotide. In D2O, deuterium replaces the OH-group at carbon-2' with retention of configuration. In addition we find 1-2% deuterium in the 3'-position demonstrating a small exchange of this hydrogen with the protons of water during catalysis. Class I and II enzymes catalyze identical reactions. Members of the three classes of reductases apparently use the same chemical mechanism in spite of having completely different protein structures.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Deoxycytidine / chemistry
  • Escherichia coli / enzymology*
  • Hydrogen / chemistry
  • Hydroxyl Radical / chemistry
  • Magnetic Resonance Spectroscopy
  • Ribonucleotide Reductases / chemistry*
  • Stereoisomerism

Substances

  • Deoxycytidine
  • Hydroxyl Radical
  • Hydrogen
  • Ribonucleotide Reductases