- Denoting the ability of normal strains of the bacterium E. coli to metabolize lactose, or the genetic factors involved in this ability (which is lost in some mutant strains): the lac operonMore example sentences
- These strains might not even use their lac gene products to metabolize lactose.
- In addition to the lac operon, a number of other synthetic and natural genetic circuits have been analyzed for robustness and evolvability.
- A metabolite of lactose binds to the lac repressor, changing the protein's shape and thereby causing it to loosen its grip on the DNA.
1940s: abbreviation of lactose.