Carbon dioxide formed from uric acid

Dietary purines are not an important source of uric acid. Quantitatively important amounts of purine are formed from amino acids, formate, and carbon dioxide in the body. Those purine ribonucleotides not incorporated into nucleic acids and derived from nucleic acid degradation are converted to xanthine or hypoxanthine and oxidized to uric acid (Figure 36-7). Allopurinol inhibits this last step, resulting in a fall in the plasma urate level and a decrease in the size of the urate pool. The more soluble xanthine and hypoxanthine are increased. 

Most weathering processes, to be sure, take place in an environment where aerobic bacteria are active, unless there are considerable quantities of nitrogenous organic matter present. Anaerobic conditions, which usually also imply pH values close to (or less than) 7, are encountered in certain marine muds, guano deposits, and elsewhere. The anaerobe, Clostridium acidiurici (Liebert), which is known to occur in soils, produces ammonia, carbon dioxide and acetic acid from uric acid, guanine and xanthine (Baker and Beck, 1942), while Streptococcus allantoicus forms — in addition to ammonia and carbon dioxide — urea, oxamic acid, etc. Oxalic acid is a common product in the decomposition of guano. 

Carbon dioxide or phosgene is employed to form uric acid (9) from 5,6-diaminopyrimidine-2,4-diol. Another route to 9 uses the fusion of 5,6-diaminopyrimidine-2,4-diol with urea. ... 

Uric acid is a fairly strong acid it dissolves readily in dilute alkali, and is precipitated from alkaline solution in the form of a sparingly soluble acid-salt by means of carbon dioxide. It is fairly resistant towards hydrolysis. Caffeine, on the other hand,... 

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