The enzymes that are required for lactose degradation: beta-galactosidase: This enzyme hydrolyzes the bond between the two sugars, glucose and galactose. It is coded for by the gene LacZ. Lactose Permease: This enzyme spans the cell membrane and brings lactose into the cell from the outside environment. The membrane is otherwise essentially impermeable to lactose. It is coded for by the gene LacY. Thiogalactoside transacetylase: The function of this enzyme is not known. It is coded for by the gene LacA.The enzymes that are required for lactose degradation: beta-galactosidase: This enzyme hydrolyzes the bond between the two sugars, glucose and galactose. It is coded for by the gene LacZ. Lactose Permease: This enzyme spans the cell membrane and brings lactose into the cell from the outside environment. The membrane is otherwise essentially impermeable to lactose. It is coded for by the gene LacY. Thiogalactoside transacetylase: The function of this enzyme is not known. It is coded for by the gene LacA