A group of compounds also called sulfonamides. The simplest is sulfanilamide, and it bears a close resemblance to p-aminobenzoic acid. Sulfanilamide and p-aminobenzoic molecules compete during the enzymatic synthesis of folic acid (q.v.). The bacterial enzyme dihydropteroate synthetase is tricked into making a dihydropteroate containing sulfanilamide. This product cannot be converted to folate, and the bacteria are starved of the folate they require to divide, and die. Humans get the folate they need in their diet and therefore are not harmed by doses of sulfanilamide that kill bacteria. See Prontosil.
Subjects: Genetics and Genomics.