Shibuya I, Yamagoe S, Miyazaki C, Matsuzaki H, Ohta A
J Bacteriol. 1985 Feb;161(2):473-7. doi: 10.1128/jb.161.2.473-477.1985.
When cultured in the presence of 600 mM D-mannitol, Escherichia coli K-12 cells synthesized two novel phospholipids. The identities of these compounds are postulated to be phosphatidylmannitol and diphosphatidylmannitol, the sugar alcohol analogs of phosphatidylglycerol and cardiolipin, respectively. The nonacylated glycerol moieties of the normal acidic phospholipids were substituted by D-mannitol. The formation of the analogs was significantly enhanced when strains harboring the pss-1 allele, a temperature-sensitive mutation in phosphatidylserine synthase (Ohta and Shibuya, J. Bacteriol. 132:434-443, 1977), were grown at 42 degrees C, and the accumulation of the analogs was maximum in late stationary phase; more than 90% of the total cellular lipids were these novel phospholipids. Strains with a defective cardiolipin synthase (Pluschke et al., J. Biol. Chem. 253:5048-5055, 1978) failed to form the analog lipids, whereas cells with increased cardiolipin synthase activity due to the presence of a pBR322-derived recombinant plasmid containing the structural gene for cardiolipin synthase produced more mannitol lipids than wild-type strains. These observations and the structures of the analog lipids indicated that cardiolipin synthase participates in the formation of these novel phospholipids. We suggest that reversible alcoholysis and condensation, in addition to low substrate specificity of the enzyme, are the mechanisms involved in this process. Addition to the medium of other straight-chain alditols, D-arabitol, ribitol, xylitol, erythritol, and L-threitol also yielded pairs of novel phospholipids, whereas sorbitol or galactitol produced only one analog in small quantities. These acidic phospholipid analogs have not been reported in any living system. They should be useful in the study of structure-function relationships of phospholipids and in manipulating the structures of various membrane systems.
在600 mM D - 甘露糖醇存在的情况下进行培养时，大肠杆菌K - 12细胞合成了两种新型磷脂。据推测，这些化合物分别是磷脂酰甘露糖醇和二磷脂酰甘露糖醇，它们分别是磷脂酰甘油和心磷脂的糖醇类似物。正常酸性磷脂的非酰化甘油部分被D - 甘露糖醇取代。当携带pss - 1等位基因（磷脂酰丝氨酸合酶中的温度敏感突变，Ohta和Shibuya，《细菌学杂志》132:434 - 443，1977）的菌株在42℃下生长时，类似物的形成显著增强，并且类似物的积累在稳定期末期达到最大值；超过90%的总细胞脂质是这些新型磷脂。心磷脂合酶缺陷的菌株（Pluschke等人，《生物化学杂志》253:5048 - 5055，1978）无法形成类似脂质，而由于存在含有心磷脂合酶结构基因的pBR322衍生重组质粒而导致心磷脂合酶活性增加的细胞，产生的甘露糖醇脂质比野生型菌株更多。这些观察结果以及类似脂质的结构表明心磷脂合酶参与了这些新型磷脂的形成。我们认为，除了该酶的低底物特异性外，可逆醇解和缩合是此过程涉及的机制。向培养基中添加其他直链糖醇，D - 阿拉伯糖醇、核糖醇、木糖醇、赤藓糖醇和L - 苏糖醇也会产生成对的新型磷脂，而山梨醇或半乳糖醇仅少量产生一种类似物。这些酸性磷脂类似物在任何生物系统中均未被报道过。它们应有助于研究磷脂的结构 - 功能关系以及操纵各种膜系统的结构。
