Biotin, also known as vitamin H or coenzyme R,is a water-soluble B-vitamin (vitamin B7).
It is composed of a ureido (tetrahydroimidizalone) ring fused with a
tetrahydrothiophene ring. A valeric acid substituent is attached to one of the carbon atoms of the tetrahydrothiophene ring.
Biotin is a coenzyme for carboxylase enzymes, involved in the synthesis of fatty acids, isoleucine, and valine, and in gluconeogenesis.
biotin is involved in important metabolic pathways such as gluconeogenesis, fatty acid synthesis, and amino acid catabolism.
Biotin regulates the catabolic enzyme propionyl-CoA carboxylase at the posttranscriptional level whereas the holo-carboxylase
synthetase is regulated at the transcriptional level