Purines

One of several nitrogen-containing organic bases, of which adenine and guanine are the most common, that pair with pyrimidines in DNA and RNA and whose derivatives are important in metabolism.  Together with the synthesis of pyrimidines, purines form a crucial pathway for the functioning of a number of amino acids.  Meat and associated products, as well as seafoods and yeast, contain high concentrations of purines, particularly in the liver and kidneys.  While purines have important roles in in both DNA and RNA, and may in fact function as neurotransmitters, they are not found in a natural state but are the products of organic synthesis.  The end product of purine metabolism in humans is uric acid.  Consequently, a build-up of purine production due to defective enzymes that control it, can give rise to gout (a form of arthritis arising from excessive amount of uric crystals deposited in joints), and is regarded as increasing the risks of some types of cancer.  Purine and pyrimidine synthesis and metabolism have major roles in controlling embryonic and fetal development and organogenesis.  However, purinergic control of neurodevelopment also extends into postnatal life in exerting control over the maturation of oligodendrocytes and the terminal differentiation of these glial cells in completely myelinated cells.  Defects in this process can result, for example, in mental retardation.  The term purine (from pure urine) was invented by the organic chemist Emil Fischer (1852-1919).       

See Adenine, Amino acids, Cytokines, Cytosine, DNA (deoxyribonucleic acid), DNA double helix, Glial cells, Guanine, Metabolism, Nucleotide, Oligodendrocytes, Organogenesis, Pyrimidines, RNA (ribonucleic acid)