Kasamo K, Nouchi I
Department of Cell Biology, National Institute of Agrobiological Resources, Tsukuba Science City, Yatabe, Ibaraki 305, Japan.
Plant Physiol. 1987 Feb;83(2):323-8. doi: 10.1104/pp.83.2.323.
Root and hypocotyl plasma membrane H(+)-ATPases were partially purified from deoxycholate-solubilized fractions of microsomes in mung bean (Vigna radiata L.) plants in the presence of glycerol. Certain properties of the ATPases and the manner in which phospholipids affect their activity were compared. Root ATPase was similar to hypocotyl ATPase with respect to substrate specificity, salt stimulation, pH dependence, K(m) for ATP.Mg(2+) and inhibitor sensitivity, except for inhibition by vanadate. Both purified ATPases required phospholipids for their activation. Optimum concentrations of exogenously added phospholipid mixture (asolectin) to hypocotyl and root ATPase mixture were 0.03% and 1.0%, respectively. Root ATPase activation did not decrease if more than 1.0% asolectin was added. Qualitatively, phosphatidylserine and phosphatidylcholine brought about greater ATPase activation than other phospholipids. The hypocotyl ATPase was activated by phosphatidylinositol, phosphatidylserine and phosphatidylglycerol to a greater extent than the root ATPase. Root, but not hypocotyl ATPase, was slightly inhibited by the addition of phosphatidylinositol, phosphatidylethanolamine, and phosphatidic acid. The hypocotyl plasma membrane contained phosphatidylinositol + phosphatidylserine, phosphatidylglycerol and phosphatidic acid, and unsaturated fatty acids in greater abundance than the root plasma membrane. The differential activation of the plasma membrane ATPases may arise from these differences.
在甘油存在的情况下，从绿豆（Vigna radiata L.）植株微粒体的脱氧胆酸盐增溶组分中部分纯化了根和下胚轴质膜H(+) -ATP酶。比较了ATP酶的某些特性以及磷脂影响其活性的方式。根ATP酶在下述方面与下胚轴ATP酶相似：底物特异性、盐刺激、pH依赖性、ATP·Mg(2+)的米氏常数（K(m)）以及抑制剂敏感性，但对钒酸盐的抑制作用除外。两种纯化的ATP酶都需要磷脂来激活。向外源添加到下胚轴和根ATP酶混合物中的磷脂混合物（大豆卵磷脂）的最佳浓度分别为0.03%和1.0%。如果添加超过1.0%的大豆卵磷脂，根ATP酶的激活作用不会降低。定性地说，磷脂酰丝氨酸和磷脂酰胆碱比其他磷脂能带来更大的ATP酶激活作用。下胚轴ATP酶比根ATP酶在更大程度上被磷脂酰肌醇、磷脂酰丝氨酸和磷脂酰甘油激活。添加磷脂酰肌醇、磷脂酰乙醇胺和磷脂酸会轻微抑制根ATP酶，但不会抑制下胚轴ATP酶。下胚轴质膜中磷脂酰肌醇 + 磷脂酰丝氨酸、磷脂酰甘油和磷脂酸以及不饱和脂肪酸的含量比根质膜中的更丰富。质膜ATP酶的差异激活可能源于这些差异。
