Galactoside acetyltransferase


Galactoside acetyltransferase is an enzyme that transfers an acetyl group from acetyl-CoA to β-galactosides, glucosides and lactosides. It is coded for by the lacA gene of the lac operon in E. coli.

Reaction

It catalyzes the following reaction:
acetyl-CoA + beta-D-galactoside → CoA + 6-acetyl-beta-D-galactoside
The kinetics of the enzyme were delineated in 1995.

Biological role

The enzyme's role in the classical E. coli ''lac'' operon remains unclear. However, the enzyme's cellular role may be to detoxify non-metabolizable pyranosides by acetylating them and preventing their reentry into the cell.