Information AboutCoenzyme |
| CATEGORIES ABOUT COENZYME | |
| coenzymes | |
| enzymes | |
| organic compounds | |
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Coenzymes are small Organic non- Protein Molecule s that carry chemical groups between Enzyme s. TERMINOLOGY The term coenzymes is commonly used loosely, and coenzymes can also be defined as organic, non- Protein Cofactors .1 Coenzymes are also sometimes referred to as cosubstrates, but this usage is unusual. Coenzymes are consumed in the reactions in which they are substrates, for example: the coenzyme NADH is converted to NAD+ by Oxidoreductases . Coenzymes are however regenerated and their concentration maintained at a steady level in the cell. A special subset of coenzymes are Prosthetic Groups . These have more in common with Cofactors since they are tightly bound to enzymes and are not released as part of the reaction. Prosthetic groups include Molybdopterin , Lipoamide and Biotin . COENZYMES AS METABOLIC INTERMEDIATES .]] Metabolism involves a vast array of chemical reactions, but most fall under a few basic types of reactions that involve the transfer of Functional Group s.2 This common chemistry allows cells to use a small set of metabolic intermediates to carry chemical groups between different reactions.3 These group-transfer intermediates are the coenzymes. Each class of group-transfer reaction is carried out by a particular coenzyme, which is the substrate for a set of enzymes that produce it, and a set of enzymes that consume it. An example of this are the Dehydrogenase s that use Nicotinamide Adenine Dinucleotide (NADH) as a cofactor. Here, hundreds of separate types of enzymes remove electrons from their substrates and Reduce NADH and this reduced coenzyme is then a substrate for any of the Reductase s in the cell that need to reduce their substrates.4 TYPES Many coenzymes are Phosphorylated Water -soluble Vitamin s. Coenzymes are also commonly made from Nucleotide s such as Adenosine Triphosphate , the biochemical carrier of Phosphate groups, or Coenzyme A , the coenzyme that carries Acyl groups. Vitamin and nucleotide derivatives
Not related to vitamins
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