Question

Define an operon. Why are they advantageous for bacteria?

Answer 1

Operon is a set of related genes which bring about genetic and transcriptional regulation. It mainly consists of 4 parts

• Operator- it is a control element which can activate or repress transcription based on the binding of regulator protein.
• Promoter- it act as an initiation point to which RNA polymerase binds and promote the gene transcription.
• Structural genes- They code for enzyme proteins which are involved in metabolic pathway like amino acid synthesis.

In bacteria,all the structural genes are clustered together in the form of an operon which is controlled by a single promoter so that all the genes can be turned on or off together which also help the bacteria to adapt rapidly towards changing environmental conditions.The main bacterial operon is lac operon which involves the enzymes involved in lactose metabolism and tryptophan synthesis in E.coli bacteria.