1
Cofactor
Are required for active binding site
2
Allosteric activator
is a modulator that binds to protein away from binding site and turns it on
3
Competitive inhibitor
Blocks ligand binding at the binding site
4
Allosteric inhibitor
is a modulator that binds to protein away from binding site and inactivates the binding site
5
Proteolytic Activation
Protein is inactive until peptide fragments are removed