Altering the glycosylation pattern of bioactive compounds

Many bioactive natural products are glycosylated compounds in which the sug ars are important or essential for biological activity. The isolation of se veral sugar biosynthesis gene clusters and glycosyltransferases from differ ent antibiotic-producing organisms, and the increasing knowledge about thes e biosynthetic pathways opens up the possibility of generating novel bioact ive compounds through combinatorial biosynthesis in the near future. Recent advances in this area indicate that antibiotic glycosyltransferases show s ome substrate flexibility that might allow us to alter the types of sugar t ransferred to the different aglycons or, less frequently, to change the pos ition of its attachment.