Genes in an operon are transcribed as a group and have a single promoter. Each operon contains regulatory DNA sequences, which act as binding sites for regulatory proteins that promote or inhibit transcription.

What is the promoter of an operon?

Promoter – a nucleotide sequence that enables a gene to be transcribed. The promoter is recognized by RNA polymerase, which then initiates transcription. In RNA synthesis, promoters indicate which genes should be used for messenger RNA creation – and, by extension, control which proteins the cell produces.

How many promoters are in an operon?

These genes are located contiguously on a stretch of DNA and are under the control of one promoter (a short segment of DNA to which the RNA polymerase binds to initiate transcription). A single unit of messenger RNA (mRNA) is transcribed from the operon and is subsequently translated into separate proteins.