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Nucleoside Catabolism

1. Purine Catabolism
   1. Conversion of guanine to xanthine
      
      
      
      

   2. Conversion of adenine to hypoxanthine

   3. Hypoxanthine to xanthine
      
      
      
      

   4. Xanthine to Uric Acid
      
      
      
      

   5. Onwards to CO₂ and NH₃
      
      
      
      

2. Pyrimidine Catabolism (very similar in principle to the above)