Question

Brief about the lac operon induction.

Answer 1

The lac operon:

1. Prokaryotic gene regulation can be explained by the lac operon model.
2. The lac operon comprises three structural genes (lacZ, lacY, lacA) and one regulatory gene i.
3. The lacZ gene codes for β-galactosidase that break down lactose into glucose and galactose. The gene lacY encodes β-galactoside permease that transports lactose into the cell. The lacA codes for β-galactoside transacetylase.
4. The regulatory i gene encodes the repressor protein.
5. Lactose acts as an inducer in lac operon. In the absence of glucose, if lactose is provided in the growth medium of bacteria, the lactose is transported into the cell by permease.
6. The inducer binds to the repressor and causes conformational changes, thereby inactivating the repressor. The RNA polymerase binds to the operator and the structural genes are transcribed as a polycistronic mRNA.