Operons are common in bacteria, but they are rare in eukaryotes such as humans. ... For instance, a well-studied operon called the lac operon contains genes that encode proteins involved in uptake and metabolism of a particular sugar, lactose.

What organisms have lac operons?

The lactose operon (lac operon) is an operon required for the transport and metabolism of lactose in E. coli and many other enteric bacteria.

Do mammals have a lac operon?

The lac operon of Escherichia coli consists of a set of genes coordinately regulated by lactose (Jacob and Monod 1961). ... Hu and Davidson (1987) were the first to use lac elements to control reporter-gene expression reversibly in mammalian cells.