Kinetic mechanism of glutaryl-CoA dehydrogenase.
Article Details
- CitationCopy to clipboard
Rao KS, Albro M, Dwyer TM, Frerman FE
Kinetic mechanism of glutaryl-CoA dehydrogenase.
Biochemistry. 2006 Dec 26;45(51):15853-61. Epub 2006 Dec 2.
- PubMed ID
- 17176108 [ View in PubMed]
- Abstract
Glutaryl-CoA dehydrogenase (GCD) is a homotetrameric enzyme containing one noncovalently bound FAD per monomer that oxidatively decarboxylates glutaryl-CoA to crotonyl-CoA and CO2. GCD belongs to the family of acyl-CoA dehydrogenases that are evolutionarily conserved in their sequence, structure, and function. However, there are differences in the kinetic mechanisms among the different acyl-CoA dehydrogenases. One of the unanswered aspects is that of the rate-determining step in the steady-state turnover of GCD. In the present investigation, the major rate-determining step is identified to be the release of crotonyl-CoA product because the chemical steps and reoxidation of reduced FAD are much faster than the turnover of the wild-type GCD. Other steps are only partially rate-determining. This conclusion is based on the transit times of the individual reactions occurring in the active site of GCD.