 These sulfate esters are only located extracellularly, whether through excretion into the extracellular matrix (ECM) or by presentation on the cell surface.As extracellular compounds, sulfated carbohydrates are mediators of intercellular communication, cellular adhesion, and ECM maintenance.Sulfotransferases catalyze the transfer of a sulfonyl group from an activated sulfate donor onto a hydroxyl group (or an amino group, although this is less common) of an acceptor molecule.