Dapsone is used for treatment of bacterial and fungal infections as well as for immunomodulatory actions. What is mechanism of dapsone for these indication?
(A) Inhibition of cell wall synthesis (B) Inhibition of ergosterol in cell membranes (C) Inhibition of protein synthesis (D) Competition with PABA in folic acid synthesis
(D) Sulfonamides (including Dapsone and PAS) : Competitively inhibit folic acid synthase enzyme as these are PABA analogues. Trimethoprim, Pyrimethamine : Inhibit Dihydro folate reductase enzyme (DHFRase). Inhibition of ergosterol in cell membrane (in fungus and leishmania): Amphotericin B.