Which enzyme/s will be produced in a cell in which there is a non-sense mutation in the lac Y gene?

$\beta$-galactosidase is a structural gene present in segment of DNA, which carry lcdes for the synthesis of protein. Mutation in the lac Ygene of E.coli needs residues of cytoplasmic enzyme $\beta$-galactosidase. Lactose permease is a membrane protein, which is a major facilitator superfamily. Transacetylase is an enzyme transferring acetyl groups from one compound to another.