Koentsyymeille

Koentsyymeille are organic, non-protein molecules that bind to enzymes and are essential for their catalytic activity. They act as cofactors, which are molecules that assist enzymes in carrying out their functions. Unlike prosthetic groups, which are permanently attached to an enzyme, coenzymes typically bind reversibly.

These molecules play a crucial role in a vast number of metabolic processes within living organisms. They often carry chemical groups, electrons, or atoms from one enzyme to another in a metabolic pathway. For example, NAD+ and FAD are coenzymes involved in redox reactions, carrying electrons during cellular respiration and photosynthesis. Another important coenzyme is Coenzyme A, which is vital for the transport of acyl groups, such as the acetyl group in the formation of acetyl-CoA, a key intermediate in energy metabolism.

Many coenzymes are derived from vitamins. For instance, B vitamins are precursors to several essential coenzymes. Thiamine (B1) is a precursor to thiamine pyrophosphate, riboflavin (B2) to FAD, niacin (B3) to NAD+ and NADP+, pantothenic acid (B5) to Coenzyme A, pyridoxine (B6) to pyridoxal phosphate, and biotin (B7) to various carboxylases. The body cannot synthesize these vitamins and must obtain them from the diet. A deficiency in a particular vitamin can therefore lead to a deficiency in the corresponding coenzyme, impairing specific enzymatic reactions and potentially causing disease. Without their coenzymes, many enzymes would be inactive, highlighting the indispensable role of coenzymes in maintaining biological functions.