NEETBotanyBiomolecules (B)
The enzymes peroxidase and catalase catalyse the breakdown of hydrogen peroxide to water and oxygen. The cofactor present in these enzymes is:
Options
- AHaem, which is an organic compound tightly bound to the apoenzyme.
- BHaem, which is an organic compound transiently bound to the apoenzyme.
- CA metal ion, which forms coordination bonds with side chains at the active site.
- DNiacin, which is an organic compound tightly bound to the apoenzyme.
Correct answer
A. Haem, which is an organic compound tightly bound to the apoenzyme.
Step-by-step solution
In peroxidase and catalase, which catalyse the breakdown of hydrogen peroxide to water and oxygen, haem is the prosthetic group. According to NCERT, prosthetic groups are organic compounds that are distinguished from other cofactors in that they are tightly bound to the apoenzyme. Coenzymes (which contain vitamins like niacin) are organic compounds that bind transiently, while metal ions form coordination bonds. Answer: Haem, which is an organic compound tightly bound to the apoenzyme.