Purine & Pyrimidine Metabolism — Practice
A 5-year-old boy has self-mutilation (lip and finger biting), choreoathetosis, intellectual disability, and orange 'sand' (urate crystals) in his nappies, with markedly raised serum uric acid. The deficient enzyme normally catalyses which step of purine metabolism?
ADe novo conversion of IMP to AMP
BDegradation of xanthine to uric acid
CConversion of adenosine to inosine
DSalvage of hypoxanthine and guanine to their nucleotides using PRPP