文章基本信息

标题：Glycerolipid biosynthesis in rat adipose tissue. I. Properties and distribution of glycerophosphate acyltransferase and effect of divalent cations on neutral lipid formation
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作者：S. C. Jamdar ; H. J. Fallon
期刊名称：JLR Papers In Press
印刷版ISSN：0022-2275
电子版ISSN：1539-7262
出版年度：1973
卷号：14
期号：5
页码：509-516
语种：English
出版社：American Society for Biochemistry and Molecular Biology
摘要：A sensitive radioactive assay of acyl CoA: sn -glycerol-3-phosphate- O -acyltransferase (EC 2.3.1.15) was developed to study the properties and subcellular distribution of this enzyme in rat epididymal adipose tissue. The esterification of sn -glycerol-3-phosphate was measured in the presence of palmitoyl CoA or palmitate, ATP, CoA, and Mg²⁺ at pH 7.5. The presence of glycerophosphate acyltransferase was detected in both mitochondria and microsomes. The product of this reaction was identified as phosphatidate by thin-layer chromatography and dual isotope incorporation studies. Several divalent cations reduced the activity of this enzyme. Although Mg²⁺ was not required for the activity of glycerophosphate acyltransferase, its addition to the incubation mixture resulted in an increased formation of neutral lipids at the expense of phosphatidate. This result is explained by an activation of microsomal phosphatidate phosphatase (EC 3.1.3.4). The effect of Mg²⁺ was completely abolished by Ni²⁺, Co²⁺, Mn²⁺, and Zn²⁺. These studies suggest that the balance between Mg²⁺ and several other divalent ions may be important in the regulation of neutral lipid synthesis in adipose tissue.
关键词：phosphatidate formation ; Mg²⁺ ; phosphatidate phosphatase