b-galactosidase is a homotetramer with four active sites permolecule (1 per subunit). The Vmax of the purified enzyme usingONPG as substrate has been reported to be 400,000 nmoles/min/mgprotein. The molecular weight of the tetramer has been reported tobe 465,412 daltons.
Please calculate the kcat (s-1) for a single activesite of b-galactosidase.