A functional unit consisting of a promoter, an operator and a number of structural @G02604@, found mainly in prokaryotes. The structural genes commonly code for several functionally related @E02159@, and although they are transcribed as one (polycistronic) @M03857@ each is independently translated. In the typical operon, the operator region acts as a controlling element in switching on or off the synthesis of mRNA.
PAC, 1992, 64, 143. (Glossary for chemists of terms used in biotechnology (IUPAC Recommendations 1992)) on page 162 [Terms] [Paper]