Purine

Purines are a class of heterocyclic aromatic organic compounds. They consist of a pyrimidine ring fused to an imidazole ring. Purines are widely distributed in nature and are essential components of nucleic acids (DNA and RNA), where they exist as adenine (A) and guanine (G). They also participate in numerous other biochemical processes and are found in molecules such as ATP (adenosine triphosphate), GTP (guanosine triphosphate), cyclic AMP (cAMP), and coenzymes such as NAD (nicotinamide adenine dinucleotide) and CoA (coenzyme A).

The parent compound, purine, is rarely found in nature. However, its derivatives, the nucleobases adenine and guanine, along with hypoxanthine and xanthine, are biologically significant. These compounds are involved in a wide range of metabolic pathways, including energy transfer, signal transduction, and enzyme catalysis.

Purine metabolism involves the synthesis, degradation, and salvage pathways of these compounds. Abnormal purine metabolism can lead to various health problems, including gout (caused by the accumulation of uric acid, a purine breakdown product), Lesch-Nyhan syndrome (a rare genetic disorder caused by a deficiency in the enzyme hypoxanthine-guanine phosphoribosyltransferase (HGPRT)), and certain types of immunodeficiency. Dietary purines, found in foods such as meat and seafood, can contribute to elevated uric acid levels, particularly in individuals with pre-existing metabolic disorders.