Isoniazid and thioacetazone may exhibit antitubercular activity by binding directly with the active site of mycolic acid cyclopropane synthase: Hypothesis based on computational analysis

Isoniazid and thioacetazone are the two important antitubercular drugs. In case of thioacetazone it is established that it inhibits mycolic acid cyclopropane synthase but the exact binding site accounting for such inhibition is presently unknown. In case of isoniazid its action on the said enzyme is unexplored. In this work we have analyzed the binding of isoniazid and thioacetazone with mycolic acid cyclopropane synthase (CmaA1 and CmaA2) using tools of computational biology. We have observed that thioacetazone fits well at the active site of CmaA1 and CmaA2 while isoniazid binds at the active site of CmaA1 only. We have recommended experimental validation of such results. If such results are proved to be fact it will explore the exact binding site of thioacetazone and discover a new mechanism of anti-tubercular action of isoniazid.