Christiansson A, Wieslander A
Biochim Biophys Acta. 1980 Jan 25;595(2):189-99. doi: 10.1016/0005-2736(80)90083-8.
The low level of endogenous fatty acid synthesis in Acholeplasma laidlawii A strain EF22 was found to be caused by a deficiency of pantetheine in the lipid-depleted growth medium. By supplementing the oleic acid-containing medium with increasing concentrations of pantethein, saturated fatty acid synthesis was stimulated (having an apparent Km of 5 microM for pantetheine) and the incorporation of endogenously synthesized fatty acids in membrane lipids increased markedly. Furthermore, carotenoid biosynthesis was stimulated. Exogenous palmitic acid was found to inhibit partially the endogenous fatty acid synthesis. A gradual stimulation of fatty acid synthesis was accompanied by a linear increase in the molar proportion between the two dominating membrane glucolipids, monoglucosyldiacylglycerol and diglucosyldiacylglycerol. The total amount of charged membrane lipids decreased upon increasing the degree of fatty acid saturation. These regulations are discussed in terms of membrane stability, and influence of membrane molecular ordering and surface charge density on lipid polar head group synthesis.
发现在莱氏无胆甾原体A株EF22中内源性脂肪酸合成水平较低是由于脂质耗尽的生长培养基中泛酰巯基乙胺缺乏所致。通过在含油酸的培养基中补充浓度不断增加的泛酰巯基乙胺，饱和脂肪酸合成受到刺激（泛酰巯基乙胺的表观Km为5 microM），并且内源性合成的脂肪酸在膜脂中的掺入显著增加。此外，类胡萝卜素生物合成也受到刺激。发现外源性棕榈酸会部分抑制内源性脂肪酸合成。脂肪酸合成的逐渐刺激伴随着两种主要膜糖脂单葡萄糖基二酰基甘油和双葡萄糖基二酰基甘油之间摩尔比例的线性增加。随着脂肪酸饱和度的增加，带电膜脂的总量减少。从膜稳定性以及膜分子有序性和表面电荷密度对脂质极性头部基团合成的影响方面对这些调节进行了讨论。
