Kleinschmidt M G, McMahon V A
Division of Biochemistry, University Station, Box 3354, University of Wyoming, Laramie, Wyoming 82070.
Plant Physiol. 1970 Aug;46(2):290-3. doi: 10.1104/pp.46.2.290.
Cyanidium caldarium was grown at 20 and 55 C and harvested during exponential growth phase. Lipids were extracted and separated by silicic acid column and thin layer chromatography. The major glycolipids were identified as mono- and digalactosyl diglyceride and sulfolipid. Major phospholipids were identified as phosphatidyl choline and phosphatidyl ethanolamine. The cells grown at 20 C contained significantly larger quantities of these glycolipids and phospholipids than cells grown at 55 C.Fatty acid analysis showed that in all cases the cells grown at 20 C contained more unsaturated fatty acids than the cells grown at 55 C. Cells grown at 55 C were shown to lack linolenic acid, in contrast to cells grown at 20 C, which contained appreciable quantities in certain lipid components. For example, monogalactosyl diglyceride had 57% of its fatty acids in the form of linolenic acid. Cells grown at 55 C were 10 to 15 C more stable to disruption by heating than cells grown at 20 C. The greater thermostability of the latter was attributed to a higher degree of saturation of their membrane fatty acids.
嗜热蓝藻在20℃和55℃下培养，并在指数生长期收获。脂质通过硅酸柱和薄层色谱法进行提取和分离。主要糖脂被鉴定为单半乳糖二甘油酯和双半乳糖二甘油酯以及硫脂。主要磷脂被鉴定为磷脂酰胆碱和磷脂酰乙醇胺。在20℃下生长的细胞比在55℃下生长的细胞含有显著更多量的这些糖脂和磷脂。脂肪酸分析表明，在所有情况下，在20℃下生长的细胞比在55℃下生长的细胞含有更多的不饱和脂肪酸。与在20℃下生长的细胞相比，在55℃下生长的细胞被证明缺乏亚麻酸，在20℃下生长的细胞在某些脂质成分中含有相当数量的亚麻酸。例如，单半乳糖二甘油酯的脂肪酸中有57%是以亚麻酸的形式存在。在55℃下生长的细胞比在20℃下生长的细胞对加热破坏的稳定性高10至15℃。后者更高的热稳定性归因于其膜脂肪酸更高的饱和度。
