Translations:Pantothenic acid/5/en
Use in biosynthesis of coenzyme A
Pantothenic acid is a precursor to CoA via a five-step process. The biosynthesis requires pantothenic acid, cysteine, and four equivalents of ATP (see figure).
- Pantothenic acid is phosphorylated to 4′-phosphopantothenate by the enzyme pantothenate kinase. This is the committed step in CoA biosynthesis and requires ATP.
- A cysteine is added to 4′-phosphopantothenate by the enzyme phosphopantothenoylcysteine synthetase to form 4'-phospho-N-pantothenoylcysteine (PPC). This step is coupled with ATP hydrolysis.
- PPC is decarboxylated to 4′-phosphopantetheine by phosphopantothenoylcysteine decarboxylase
- 4′-Phosphopantetheine is adenylated (or more properly, AMPylated) to form dephospho-CoA by the enzyme phosphopantetheine adenylyl transferase
- Finally, dephospho-CoA is phosphorylated to coenzyme A by the enzyme dephosphocoenzyme A kinase. This final step also requires ATP.<