Kanegasaki S, Jann K
Eur J Biochem. 1979 Apr 2;95(2):287-93. doi: 10.1111/j.1432-1033.1979.tb12964.x.
The activity in vitro of the mannan-synthesizing system of Escherichia coli O9 depends on the presence of glucose in the growth medium of the bacteria. Inactive membranes of E. coli strain F988 grown without gain mannan-synthesizing activity by reconstitution with a butanol extract obtained from the same bacteria grown with glucose. Inactive membranes could also be restored to biosynthetic activity by incubation with UDP-glucose in the presence of magnesium chloride. In this magnesium-ion-dependent reaction, a glucolipid was formed which was extractable with butanol. It could be used for the reconstitution of inactive membranes. The products of incubations with GDP-mannose of reconstituted and active membranes were analysed for electrophoretic mobility in sodium dodecylsulfate/polyacrylamide gel electrophoresis, molecular weight and composition. In all cases they proved to be the mannan attached to a hydrophobic mannose carrier, presumably a glucolipid. These results suggest that a glucolipid is the intermediary mannose acceptor in the biosynthesis of the O9 antigen.
大肠杆菌O9的甘露聚糖合成系统的体外活性取决于细菌生长培养基中葡萄糖的存在。在无葡萄糖条件下生长的大肠杆菌F988菌株的无活性膜，通过用从在有葡萄糖条件下生长的同一细菌中获得的丁醇提取物进行重构，可获得甘露聚糖合成活性。无活性膜在氯化镁存在下与UDP-葡萄糖一起温育，也可恢复生物合成活性。在这个依赖镁离子的反应中，形成了一种可用丁醇提取的糖脂。它可用于无活性膜的重构。对重构膜和活性膜与GDP-甘露糖温育的产物进行十二烷基硫酸钠/聚丙烯酰胺凝胶电泳分析，测定其电泳迁移率、分子量和组成。在所有情况下，它们都被证明是附着在疏水甘露糖载体（可能是一种糖脂）上的甘露聚糖。这些结果表明，糖脂是O9抗原生物合成中甘露糖的中间受体。
