Pantothenic acid (Vitamin B5)
Free online lectures on Biochemistry especially for medical students by the Biochemistry Club
- Pantothenic acid is widely distributed in nature (“Pantos” is a Greek word meaning everywhere).
- Pantothenic acid contains beta- alanine and D-pantoic acid in amide linkage.
Structure of Pantothenic acid
- Pantothenic acid is a part of co-enzyme A (CoA) along with beta mercaptoethanol amine.
- Synthesis of CoA needs the expenditure of 4 high energy bonds.
Coenzyme activity of Pantothenic acid
- Pantothenic acid is a component of Coenzyme A, which takes part in the transfer of acyl groups because of its thiol (sulfhydryl or SH) group.
- The SH group is the active site where acyl groups are carried.
- The thioester bond in Acyl-CoA is a high energy bond. These acyl groups are transferred to other acceptors.
- Examples of compounds with acyl groups are Succinyl CoA, Fatty acyl CoA and Acetyl CoA, HMG Co A.
- Coenzyme A takes part in reactions of the Citric acid cycle, FA synthesis & oxidation, acylations and cholesterol synthesis.
- Coenzyme A is an important component of fatty acid synthase complex.
- The 4-phospantetheine group of the acyl carrier protein (ACP) of the FA synthase multi-enzyme complex is derived from pantothenic acid.
- This reactive group of the ACP is in close proximity with the cysteinyl group of the ketoacyl synthase part of the adjoining monomer.
FOR COMPLETE VIEW OF THE TOPICS VISIT THE VITAMINS PART IN THE “BIOCHEMISTRY I”. CLICK THE CURRICULUM TAB TO VIEW THE LIST OF LESSONS.