Kinetic and mechanistic characterization of the formyl-CoA transferase from Oxalobacter formigenes

J Biol Chem. 2004 Aug 20;279(34):36003-12. doi: 10.1074/jbc.M404873200. Epub 2004 Jun 21.

Abstract

Oxalobacter formigenes is an obligate anaerobe that colonizes the human gastrointestinal tract and employs oxalate breakdown to generate ATP in a novel process involving the interplay of two coupled enzymes and a membrane-bound oxalate:formate antiporter. Formyl-CoA transferase is a critical enzyme in oxalate-dependent ATP synthesis and is the first Class III CoA-transferase for which a high resolution, three-dimensional structure has been determined (Ricagno, S., Jonsson, S., Richards, N., and Lindqvist, Y. (2003) EMBO J. 22, 3210-3219). We now report the first detailed kinetic characterizations of recombinant, wild type formyl-CoA transferase and a number of site-specific mutants, which suggest that catalysis proceeds via a series of anhydride intermediates. Further evidence for this mechanistic proposal is provided by the x-ray crystallographic observation of an acylenzyme intermediate that is formed when formyl-CoA transferase is incubated with oxalyl-CoA. The catalytic mechanism of formyl-CoA transferase is therefore established and is almost certainly employed by all other members of the Class III CoA-transferase family.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Bacterial Proteins / chemistry*
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Catalytic Domain
  • Coenzyme A-Transferases / chemistry*
  • Coenzyme A-Transferases / genetics
  • Coenzyme A-Transferases / metabolism
  • Humans
  • Kinetics
  • Molecular Structure
  • Mutation
  • Oxalobacter formigenes / enzymology*
  • Protein Conformation
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Structure-Activity Relationship

Substances

  • Bacterial Proteins
  • Recombinant Proteins
  • Coenzyme A-Transferases
  • formyl-coenzyme A transferase

Associated data

  • PDB/1T3Z
  • PDB/1T4C
  • PDB/1VGQ
  • PDB/1VGR