PROSTHETIC GROUP AS NON POLYPEPTIDE BIOCATALYST ESSENTIAL FOR BIOCHEMICAL CHEMISTRY

Tinkal S. Patel, Harsh J. Patel, Jalpa G. Patel, Anjali Sinha and Prof. Dr. Dhrubo Jyoti Sen*

ABSTRACT

A tightly bound non-polypeptide structure required for the activity of an enzyme or other protein, for example the haem of haemoglobin. A characteristic non amino acid substance that is strongly bound to a protein and necessary for the protein portion of an enzyme to function; often used to describe the function, as in hemeprotein for hemoglobin. An organic and non-protein compound that forms a part of conjugated proteins. In enzymatic catalysis the prosthetic group is usually referred to as a coenzyme. Coenzymes are firmly bonded to the protein part of a biocatalyst by an apoenzyme and remain affixed to the protein molecule for the duration of the catalysis; examples of coenzymes include lipoic acid, riboflavin, biotin and hemes. Carrier coenzymes differ from prosthetic groups. The activity of carrier coenzymes is associated with their transfer from one enzyme molecule to another. However, this differentiation is often arbitrary, since the same compound (for example, FAD: flavine-adenine di-nucleotide) can sometimes act like a typical dissociating coenzyme, while at other times it remains firmly bonded to the protein.

Keywords: Organic units, Inorganic units, Metal complex, Cofactors, Coenzymes, Proteins, Vitamins, Sugars, Lipids, Enzyme partners, NAD, FAD.