Question

The structural gene which synthesizes mRNA that translates the permease protein is

• A. Y- gene
• B. $P^{53}$ gene
• C. A- gene
• D. Z- gene

Answer 1

The correct option is A Y- gene

The lac operon is an operon responsible for transport and metabolism of lactose in Escherichia coli and other bacteria and carries the genes that codes for enzymes involved in lactose metabolism only. The lac operon has three structural genes. The lac Z gene codes for beta-galactosidase which converts lactose into glucose and galactose; option D is incorrect. Option A is correct as lac Y gene that codes for beta-galactoside permease which transports lactose into the cell. The lac A gene codes for beta-galactoside transacetylase; option C is incorrect. Option B is incorrect as it is not part of the lac operon. The correct answer is A.