Wightman P D, Raetz C R
J Biol Chem. 1984 Aug 25;259(16):10048-52.
The monosaccharide lipid A precursor, N2,O3-diacylglucosamine 1-phosphate (Escherichia coli lipid X), has been shown previously to be a potent B-lymphocyte mitogen. We now report that lipid X interacts with macrophages, stimulating turnover of phosphatidylinositol, deacylation of phospholipids, and release of arachidonic acid. In addition, the monosaccharide lipid X, the incomplete lipid A disaccharides found in KDO-deficient mutants, and crude free lipid A by itself activate protein kinase C isolated from RAW 264.7 macrophages. This activation is augmented by diglyceride, a product of phosphatidylinositol turnover. Like the lipid X-induced mitogenesis of B-lymphocytes, lipid X activation of macrophages and the cell-free activation of protein kinase by lipid X require the presence of the O-linked hydroxymyristoyl residue at position 3. We suggest, therefore, that some of the biological effects of lipid A may be mediated by its interaction with protein kinase C.
单糖脂质A前体，N2,O3-二酰基葡糖胺1-磷酸（大肠杆菌脂质X），先前已被证明是一种有效的B淋巴细胞有丝分裂原。我们现在报告脂质X与巨噬细胞相互作用，刺激磷脂酰肌醇的周转、磷脂的脱酰基作用以及花生四烯酸的释放。此外，单糖脂质X、在缺乏KDO的突变体中发现的不完全脂质A二糖以及粗制游离脂质A本身可激活从RAW 264.7巨噬细胞中分离出的蛋白激酶C。二酰甘油是磷脂酰肌醇周转的产物，它可增强这种激活作用。与脂质X诱导的B淋巴细胞有丝分裂一样，脂质X对巨噬细胞的激活以及脂质X对蛋白激酶的无细胞激活都需要在3位存在O-连接的羟肉豆蔻酰残基。因此，我们认为脂质A的某些生物学效应可能是由其与蛋白激酶C的相互作用介导的。
