An enzymatically active medical article is provided, which comprises a medical article and an enzyme disposed at or near a surface of the medical article such that the medical article is provided with an enzymatically active surface. The enzyme is selected, for example, from the group consisting of protease enzymes, glycosidase enzymes, enzymes that degrade cholesterol esters, enzymes that convert hydrocortisone to cortisone, enzymes that degrade oxalate, and enzymes that generate NO from arginine.