Phosphatidylinositol synthase from canine pancreas: solubilization by n-octyl glucopyranoside and stabilization by manganese.
Phosphatidylinositol synthase from canine pancreas: solubilization by n-octyl glucopyranoside and stabilization by manganese.
复制标题
来自犬胰腺的磷脂酰肌醇合酶：通过正辛基吡喃葡萄糖苷增溶并通过锰稳定化。
DOI：
10.1021/bi00315a039
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发表时间：
1984
期刊：
影响因子：
2.9
通讯作者：
Hokin-Neaverson,M
中科院分区：
文献类型：
--
作者：
Parries,GS;Hokin-Neaverson,M
Gregory S. Parries和美宝Hokin-Neaverson** 摘要：磷脂酰肌醇合酶（CDP-1，2-二酰基-β-甘油：β-γ-肌醇3-磷脂酰转移酶）在哺乳动物胰腺中是有活性的，在激动剂刺激的肌醇-磷脂代谢过程中，它在磷脂酰肌醇（PI）的再合成中起作用。发现该酶在狗胰腺微粒体膜中以相对高的比活性[30 nmol PI形成min-1（mg蛋白）-1]存在，并且其在这些膜中的活性被部分表征。肌醇的Km为0.76 mM，胞苷（5 '）二磷酸-1，2-二酰基甘油（CDP-二酰基甘油）的表观Km为18 µ。Mn 2+和Mg 2+活化的表观Ka值分别为42 μ M和2.5 mM，最适pH为8.5-9.0。用40 mM正辛基吡喃葡萄糖苷（OG），以4-6 mg OG/mg
Gregory S. Parries and Mabel Hokin-Neaverson** abstract: Phosphatidylinositol synthase (CDP-l, 2-diacyl-i «-glycerol:» y> o-inositol 3-phosphatidyltransferase) is active in mammalian pancreas, where it plays a role in the resynthesis of phosphatidylinositol (PI) duringagonist-stimulated inosi-tol-phospholipid metabolism. The enzyme was found to be present in relatively high specific activity [30 nmol of PI formed min" 1 (mg of protein)" 1] in dog pancreas microsomal membranes, and its activity in these membranes was partially characterized. The Km for myoinositol was 0.76 mM, and the apparent Km for cytidine (5') diphospho-1, 2-diacylglycerol (CDP-diacylglycerol) was 18 µ. The apparent Ka values for activation byMn2+ and Mg2+ were respectively 42 µ and 2.5 mM. The pH optimum was 8.5-9.0. The enzyme was solubilized in stable form and in nearly quantitative yieldwith 40 mM n-octyl glucopyranoside (OG), with 4-6 mg of OG/mg