AIIMS November 2011 – MCQ 17

All of the following are true regarding oxygenases except :
A. Incorporate 2 atoms of oxygen
B. Incorporate 1 atom of oxygen
C. Required for hydroxylation of steroids
D. Required for carboxylation of drugs

(Repeat question – AIPGME 07 MK q30)

Correct answer : Required for carboxylation of drugs
Ref: Harper 27th p96,97

Explanation:

  • Carboxylation is done by ligases.
  • Monooxygenases and dioxygenases incorporate 1 and 2 atoms of oxygen respectively
  • Monoxygenases are required for hydroxylation of steroids