Sulfation of Phenolic Antibiotics by Sulfotransferase Obtained from a Human Intestinal Bacterium

Abstract

Novel sulfotransferase which was isolated from Eubacterium A-44, a human intestinal bacterium, sulfated phenolic antibiotics, such as amoxicillin, ceaodroxil and cefoperazone. The K_m values of sulfotransferase for these antibiotics were 6.9, 4.3 and 22.2 mM, respectively. The V_max values were 8.3, 3.3 and 1.6 μmol/min/mg protein. The optimal pH of the enzyme was 9.0, a weakly alkaline region. The antibacterial activity of amoxicillin was not altered by enzymic sulfation of the phenolic hydroxyl group.