Gout is a form of arthritis in which tiny crystals of uric acid develop within and around the joints. It leads to sudden episodes of intense pain and swelling. The diagram illustrates how uric acid is produced from hypoxanthine, with the reaction catalysed by the enzyme xanthine oxidase. Gout may be treated with a drug named allopurinol, which has a shape similar to hypoxanthine. What conclusion can be drawn from this information about the way allopurinol stops uric acid from being formed?
- AIt binds to the active site of xanthine oxidase instead of hypoxanthine, resulting in reduced production of uric acid.
- BIt binds to another part of xanthine oxidase and this changes the shape of the active site.
- CIt disrupts the hydrogen bonds within xanthine oxidase so it denatures and the active site is no longer complementary to hypoxanthine and xanthine.
- DIt hydrolyses the peptide bonds within xanthine oxidase to change the shape of the active site.