Lac repressor
Trp repressor
1. Lac repressor gene produces active repressor protein.
1. Trp repressor gene produces inactive repressor protein.
2. Repressor protein can bind to operator region alone.
2. Repressor protein cannot bind to operator region alone.
3. Repressor protein is inactivated by allolactose molecule which is isomer of lactose (inducers) molecules.
3. Repressor protein is activated by tryptophan (co-repressor) molecules.