Some specific reactions of the purine-oxidizing system of Pseudomonas aeruginosa

• 1.1. Whole resting cells of Pseudomonas aeruginosa oxidise 2-aminopurine as well as the 2-methylamino- and 2-dimethylamino derivative at position 8, in contrast to previous observations with mammalian xanthine oxidase.
• 2.2. 6-Mercaptopurine is attacked first at C-2, then at C-8. The resulting 6-thiouric acid is degraded further.
• 3.3. 6-Mercaptopurine does not inhibit growing cells of P. aeruginosa, but increases production of the bacterial xanthine oxidase.
• 4.4. The 3-methyl derivatives of thioxanthines are oxidised at position 8, while 3-methylhypoxanthine is attacked first at C-2. The resulting complex, containing 3-methylxanthine, dissociates before further oxidation to 3-methyluric acid can take place, in contrast to xanthine.