How Does Triclosan Work?


Fatty acid synthesis in bacteria is a multi-reaction process with different enzymes catalyzing each chemical reaction. One gene encodes one enzyme; Triclosan interferes with the gene that regulates the entire process. For example, in E. coli and M. tuberculosis bacteria, the regulatory gene, named FabI, encodes the enzyme called enoyl-acyl carrier protein reductase (ENR) (Kapoor). Triclosan acts as a competitive inhibitor when it binds to the active site of the ENR enzyme and forms a FabI-NAD+-triclosan complex (Heath). Triclosan steals the active site on the ENR enzyme to form a complex never intended by the regulatory gene. The complex is analogous to a defected product in a factory. The formation of this complex signals Triclosan’s success. The alternate complex is unable to continue in the process of fatty acid synthesis, effectively ending the elongation of the fatty acid. Construction and maintenance of the cell membrane relies on synthesis of fatty acids. Triclosan impedes fatty