McMurray W C, Jarvis E C
Can J Biochem. 1978 Jun;56(6):414-9. doi: 10.1139/o78-065.
The enzyme which catalyzes the synthesis of phosphatidylgly cerophosphate from an-glycerol-3-phosphated and cytidine diphosphate diacylglycerol was released from rat or pig liver mitochondrial membranes by extraction with Triton X-100 or Nonidet P-40. The detergent-extracted enzyme, like the activity of intact mitochondria, did not require added cations or lipids. The Triton extracts were fractionated by column chromatography on Bio-Gel A-1.5. The fractions obtained from the columns exhibited little activity in the standard assay system unless divalent cations were included. Additional stimulation (about twofold) was observed in the presence of added phospholipids. The cation requirement of the purified enzyme was relatively nonspecific with Mg2+, Ba2+, or Ca2+ providing maximal activity in the 10mM range. Either Mn2+ or Co2+ were stimulatory at somewhat lower concentrations but higher concentrations were inhibitory. Other cations such as Cd2+, Zn2+,Hg2+, or Cu2+ were ineffective as cofactors, and in the presence of Mg2+ inhibited the reaction at concentrations greater than 0.5 mM. The phospholipik stimulation was obtained specifically with phosphatidylethanolamines from natural or synthetic sources. Other diacylglycerophosphatides or lysophosphatides including lysophosphatidylethanolamine were ineffective.
通过用Triton X - 100或Nonidet P - 40提取，从大鼠或猪肝线粒体膜中释放出催化由3 - 磷酸甘油和胞苷二磷酸二酰基甘油合成磷脂酰甘油磷酸的酶。经去污剂提取的酶，如同完整线粒体的活性一样，不需要添加阳离子或脂质。用Bio - Gel A - 1.5对Triton提取物进行柱层析分离。除非加入二价阳离子，从柱上获得的级分在标准测定系统中显示出很少的活性。在添加磷脂的情况下观察到额外的刺激作用（约两倍）。纯化酶对阳离子的需求相对非特异性，Mg2 +、Ba2 +或Ca2 +在10mM范围内提供最大活性。Mn2 +或Co2 +在稍低浓度下有刺激作用，但较高浓度时则有抑制作用。其他阳离子如Cd2 +、Zn2 +、Hg2 +或Cu2 +作为辅因子无效，并且在存在Mg2 +时，浓度大于0.5mM时会抑制反应。磷脂刺激作用特别是由天然或合成来源的磷脂酰乙醇胺产生的。其他二酰基甘油磷脂或溶血磷脂，包括溶血磷脂酰乙醇胺均无效。
