- One of the two major purines (the other being guanine) found in both RNA and DNA, and also in various free nucleotides of importance to the body, such as AMP (adenylic acid), ATP, NAD+ and NADP+, and FAD; in all these smaller compounds, a. is condensed with ribose at nitrogen-9, forming adenosine. For structure, see adenylic acid. SYN: 6-aminopurine.- a. deaminase an enzyme that catalyzes the hydrolysis of a. to ammonia and hypoxanthine. A part of purine degradation.- a. phosphoribosyltransferase an enzyme that catalyzes the reaction of a. with 5-phospho-α-d-ribose 1-diphosphate (PRPP) to form AMP and pyrophosphate. An important step in purine salvage. A deficiency of this enzyme can lead to 2,8-dihydroxyadenine lithiasis.- a. sulfate a. conjugated with sulfuric acid; used to stimulate leukocyte production in agranulocytosis.
* * *ad·e·nine 'ad-ən-.ēn n a purine base C5H5N5 that codes hereditary information in the genetic code in DNA and RNA compare CYTOSINE, GUANINE, THYMINE, URACIL
* * *n.one of the nitrogen-containing bases (see purine) that occurs in the nucleic acids DNA and RNA. See also ATP.
* * *ad·e·nine (adґə-nēn) 1. a major purine base (see illustration at base). In animal and plant cells it usually occurs condensed with ribose or deoxyribose to form the nucleosides adenosine and deoxyadenosine. As such, it is a component of nucleic acids, of certain nucleotides, and of many coenzymes. Symbol A. 2. [USP] a preparation of adenine used to improve the preservation of whole blood.
Medical dictionary. 2011.