Bohn M, Heinz E, Lüthje S
Institut für Allgemeine Botanik, Universität Hamburg, Germany.
Arch Biochem Biophys. 2001 Mar 1;387(1):35-40. doi: 10.1006/abbi.2000.2224.
Although the results of lipid analyses from several plant species have been available for many years a complete characterization of the corn root plasma membrane is still lacking. The present study provides a detailed analysis of individual lipids and a characterization of the membrane fluidity of corn (Zea mays L.) root plasma membranes isolated by phase-partitioning. Phospholipids (43.9 mol%), sterols (40.8 mol%), and sphingolipids in the form of glucocerebroside (6.8 mol%) constitute the major lipid classes. Stigmasterol (19.8 mol%), campesterol (13.0 mol%), phosphatidylcholine 15.8 mol%), and phosphatidylethanolamine (14.2 mol%) represent the most ubiquitous individual lipids. Hydroxy fatty acids make up 80.9 mol% and very long chain fatty acids are almost 78% of fatty acids in glucocerebroside. Hydroxy arachidic acid (20:0 h) and hydroxy lignoceric acid (24:0 h) are most prominent and glucocerebroside from corn root plasma membranes contains virtually no unsaturated fatty acids. Among the phospholipids only phosphatidylserine displayed a high proportion of very long chain fatty acids (e.g., behenic and lignoceric acid). Membrane fluidity was estimated by fluorescence anisotropy. Due to the high sterol content the plasma membrane of corn roots is relatively rigid.
尽管多种植物的脂质分析结果已问世多年，但玉米根质膜的完整表征仍付诸阙如。本研究详细分析了单个脂质，并对通过相分离法分离的玉米（Zea mays L.）根质膜的膜流动性进行了表征。磷脂（43.9摩尔%）、甾醇（40.8摩尔%）以及葡萄糖脑苷脂形式的鞘脂（6.8摩尔%）构成了主要的脂质类别。豆甾醇（19.8摩尔%）、菜油甾醇（13.0摩尔%）、磷脂酰胆碱（15.8摩尔%）和磷脂酰乙醇胺（14.2摩尔%）是最常见的单个脂质。羟基脂肪酸占脂肪酸的80.9摩尔%，超长链脂肪酸在葡萄糖脑苷脂的脂肪酸中几乎占78%。羟基花生酸（20:0 h）和羟基木蜡酸（24:0 h）最为突出，玉米根质膜中的葡萄糖脑苷脂几乎不含不饱和脂肪酸。在磷脂中，只有磷脂酰丝氨酸显示出高比例的超长链脂肪酸（例如山嵛酸和木蜡酸）。通过荧光各向异性估计膜流动性。由于甾醇含量高，玉米根的质膜相对刚性。
