Hutchinson Eve, Murphy Barry, Dunne Terence, Breen Ciaran, Rawlings Bernard, Caffrey Patrick
School of Biomolecular and Biomedical Science and Centre for Synthesis and Chemical Biology, University College Dublin, Belfield, Dublin 4, Ireland.
Chem Biol. 2010 Feb 26;17(2):174-82. doi: 10.1016/j.chembiol.2010.01.007.
Most polyene macrolide antibiotics are glycosylated with mycosamine (3,6-dideoxy-3-aminomannose). In the amphotericin B producer, Streptomyces nodosus, mycosamine biosynthesis begins with AmphDIII-catalyzed conversion of GDP-mannose to GDP-4-keto-6-deoxymannose. This is converted to GDP-3-keto-6-deoxymannose, which is transaminated to GDP-mycosamine by the AmphDII protein. The glycosyltransferase AmphDI transfers mycosamine to amphotericin aglycones (amphoteronolides). The aromatic heptaene perimycin is unusual among polyenes in that the sugar is perosamine (4,6-dideoxy-4-aminomannose), which is synthesized by direct transamination of GDP-4-keto-6-deoxymannose. Here, we use the Streptomyces aminophilus perDII perosamine synthase and perDI perosaminyltransferase genes to engineer biosynthesis of perosaminyl-amphoteronolide B in S. nodosus. Efficient production required a hybrid glycosyltransferase containing an N-terminal region of AmphDI and a C-terminal region of PerDI. This work will assist efforts to generate glycorandomized amphoteronolides for drug discovery.
大多数多烯大环内酯类抗生素都与肌糖胺（3,6-二脱氧-3-氨基甘露糖）糖基化。在两性霉素B产生菌诺卡氏链霉菌中，肌糖胺生物合成始于由AmphDIII催化的GDP-甘露糖向GDP-4-酮-6-脱氧甘露糖的转化。此产物再转化为GDP-3-酮-6-脱氧甘露糖，后者由AmphDII蛋白转氨生成GDP-肌糖胺。糖基转移酶AmphDI将肌糖胺转移至两性霉素苷元（两性霉素烯醇化物）上。芳香族七烯类的伯霉素在多烯类中较为特殊，其糖为鼠李糖胺（4,6-二脱氧-4-氨基甘露糖），它是由GDP-4-酮-6-脱氧甘露糖直接转氨合成的。在此，我们利用嗜氨基链霉菌的perDII鼠李糖胺合酶基因和perDI鼠李糖胺基转移酶基因，在诺卡氏链霉菌中构建鼠李糖胺基两性霉素烯醇化物B的生物合成途径。高效生产需要一种包含AmphDI N端区域和PerDI C端区域的杂合糖基转移酶。这项工作将有助于为药物研发生成糖基随机化的两性霉素烯醇化物。
