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pur·ine (Pur),(pyūr'ēn, -rin),
The parent substance of adenine, guanine, and other naturally occurring purine "bases."
purine/pu·rine/ (pūr´ēn) a compound, C5H4N4, not found in nature, but variously substituted to produce a group of compounds, purines or purine bases, which include adenine and guanine found in nucleic acids and xanthine and hypoxanthine.
1. A double-ringed, crystalline organic base, C5H4N4, that is the parent compound of a large group of biologically important compounds.
2. Any of a group of substituted derivatives of purine, including the nitrogen bases adenine and guanine, which are components of nucleic acids. Uric acid, caffeine, theobromine, and theophylline are also purines.
Etymology: L, purus, pure, urina, urine
any one of a large group of nitrogenous compounds. Purines are produced as end products in the digestion of certain proteins in the diet, but some are synthesized in the body. Purines are also present in many medications and other substances, including caffeine, theophylline, and various diuretics, muscle relaxants, and myocardial stimulants. Hyperuricemia may develop in some people as a result of an inability to metabolize and excrete purines. A low-purine diet or a purine-free diet may be required. Foods that are high in purines include anchovies and sardines; sweetbreads, liver, kidneys, and other organ meats; legumes; and poultry. The foods lowest in purine content include eggs, fruit, cheese, nuts, sugar, gelatin, and vegetables other than legumes.
The parent substance of adenine, guanine, and other naturally occurring so-called purine bases; not known to exist as such in mammals.
purineone of two types of base found in NUCLEIC ACIDS, having a double ring structure; see ADENINE and GUANINE. Purines always pair with PYRIMIDINES in the two strands of DNA, ensuring a parallel-sided molecule.
A white crystalline substance that is one of the building blocks of DNA. Uric acid is produced when purine is broken down in the body.
a heterocyclic compound that is the nucleus of the purine bases (or purines) such as adenine and guanine, which occur in DNA and RNA, and xanthine and hypoxanthine. All living cells contain purines as purine nucleotides. They can be synthesized using amino acids, or by salvage of dietary or endogenous nucleotides derived from cell wastage.
low purine diet
one with a low content of organ meats, seafood, beans, lentils, peas and spinach; used in the dietary management of xanthine or urate uroliths in dogs.
purine nucleoside phosphorylase
a transferase enzyme that acts in the degradation of nucelotides and nucleic acids.