What type of bacteria does Sulfanilamide primarily target?

Sulfanilamide primarily targets gram-positive bacteria due to its mechanism of action, which inhibits the synthesis of folic acid—a crucial component for bacterial growth and replication. Gram-positive bacteria often depend more heavily on folic acid synthesis since they cannot absorb folate from their environment and must produce it internally.

Sulfanilamide acts as a structural analog of para-aminobenzoic acid (PABA), a substrate for the bacterial enzyme dihydropteroate synthase, which plays a key role in folate synthesis. By blocking this process, sulfanilamide effectively prevents gram-positive bacteria from producing essential nucleic acids and proteins necessary for their growth.

While sulfanilamide can have some activity against certain gram-negative bacteria under specific conditions, its primary efficacy and intended use have historically been more associated with gram-positive bacteria. Therefore, the focus on gram-positive organisms aligns with its mechanism and clinical application.