Anaerobic degradation of pteridines and purines by intestinal organisms.

Microorganisms located within rat cecal contents degraded or catabolized [2-14C]pteridines and [2-14C]purines under anaerobic conditions, resulting in the release of 14CO2. A saturating concentration of guanosine did not affect the rate of release of CO2 from biopterin, and, likewise, the presence of a saturating level of biopterin did not significantly alter the release of CO2 from guanosine, indicating that the catabolism of these two compounds was by different systems. Part of the catabolic organisms for guanosine were segregated in a culture dilution experiment. These catabolic activities were detected in feces of humans and various other mammals. The results are compared with previously published data on the degradation of pteridines and purines.