<prompt> Coenzyme in carboxylation reactions:PyridoxineThiamineBiotinCyanocobalamin  <response>: Biotin Vitamin H Coenzyme RIt 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. 