FAD binding, cobinamide binding and active site communication in the corrin reductase (CobR)

Andrew D. Lawrence, Samantha L. Taylor, Alan Scott, Michelle L. Rowe, Christopher M. Johnson, Stephen E.J. Rigby, Michael A. Geeves, Richard W. Pickersgill, Mark J. Howard, Martin J. Warren

Research output: Contribution to journalArticlepeer-review

6 Citations (Scopus)


Adenosylcobalamin, the coenzyme form of vitamin B12, is one Nature's most complex coenzyme whose de novo biogenesis proceeds along either an anaerobic or aerobic metabolic pathway. The aerobic synthesis involves reduction of the centrally chelated cobalt metal ion of the corrin ring from Co(II) to Co(I) before adenosylation can take place. A corrin reductase (CobR) enzyme has been identified as the likely agent to catalyse this reduction of the metal ion. Herein, we reveal how Brucella melitensis CobR binds its coenzyme FAD (flavin dinucleotide) and we also show that the enzyme can bind a corrin substrate consistent with its role in reduction of the cobalt of the corrin ring. Stopped-flow kinetics and EPR reveal a mechanistic asymmetry in CobR dimer that provides a potential link between the two electron reduction by NADH to the single electron reduction of Co(II) to Co(I).

Original languageEnglish
Article numbere00120
Pages (from-to)345-355
Number of pages11
JournalBioscience Reports
Issue number4
Publication statusPublished - 2014


  • Enzyme kinetics
  • Enzyme structure
  • NMR
  • Vitamins and cofactors
  • X-ray crystallography

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