Beta-galactoside transacetylase

β-galactoside transacetylase is an enzyme that transfers an acetyl group from acetyl-CoA to β-galactosides, and is coded by a gene (lacA) in the lac operon of E. coli. Its precise function as part of the lac operon is not understood currently.

The kinetics of the enzyme were delineated in 1995.

The enzyme's cellular role may be to detoxify non-metabolizable pyranosides by acetylating them and preventing their reentry into the cell.