Also known as the “o locus.” The site on the DNA to which a repressor molecule binds to prevent the initiation of transcription. The operator locus is a distinct entity and exists independently of the structural genes and the regulatory gene. It is the structural/biochemical “switch” with which the operon is turned on or off, and it controls the transcription of an entire group of coordinately induced genes. One type of mutation of the operator locus is called operator constitutive mutants. Constitutive mutants continually chum out the protein characteristic for that operon because the operon unit cannot be turned off by the repressor molecule.
Someone whose job is to operate a machine or piece of equipment.
A surgeon who operates on people.