Transcription is defined as the transfer of genetic information from deoxyribonucleic acid (DNA) to ribonucleic acid (RNA). The process of transcription in prokaryotic cells (e.g., bacteria) differs from the process in eukaryotic cells (cells with a true nucleus) but the underlying result of both transcription processes is the same, which is to provide a template for the formation of proteins.

The use of DNA as a blueprint to manufacture RNA begins with an enzyme called RNA polymerase. The enzyme is guided to a certain region on the DNA, called the promoter, by association with molecules known as sigma factors. There are many promoters on DNA, located just before a region of DNA that codes for a protein. The promoter serves to position the RNA polymerase so that transcription of the full coding region is accomplished.

Once the polymerase has bound to a promoter, the sigma factors detach...