Nahas N, Juhl H, Esmann V
Mol Cell Biochem. 1984;58(1-2):147-56. doi: 10.1007/BF00240614.
Synthase phosphatase, phosphorylase phosphatase and histone phosphatase activity in a leukocyte homogenate were found to have different sedimentation characteristics: both synthase phosphatase and phosphorylase phosphatase activity are associated with the microsomal fraction, while the majority of histone phosphatase activity (75-85%) was found in the cytosol. Synthase phosphatase, phosphorylase phosphatase and histone phosphatase activities accompanying the microsomal fraction are readily solubilized by 0.3% Triton X-100. When the solubilized microsomal enzymes were chromatographed on Sephadex G-200, the majority of synthase phosphatase, phosphorylase phosphatase and histone phosphatase activity migrated in single peaks corresponding to apparent molecular weights of 380 000, 250 000 and 68 000, respectively. A minor peak of 30 000, which had phosphatase activity against all three substrates was also obtained. Ethanol treatment resulted in solubilization and dissociation of the three phosphatase activities. It was found that although ethanol treatment resulted in a 4-fold increase of phosphorylase phosphatase activity, histone phosphatase activity was decreased (by 60%), while synthase phosphatase activity remained stable. Similar results were obtained when ethanol treatment was performed on the 17 000 X g supernatant. Chromatography of the ethanol-treated microsomes (or homogenate) on Sephadex G-200 showed that the phosphatase activity towards synthase D, phosphorylase a and phosphohistone coincided a Mr 30 000 species. Heat treatment of the Mr 30 000 peak resulted in dissociation of synthase phosphatase and phosphorylase phosphatase activity. Synthase phosphatase was inhibited by phosphorylase a in a kinetically non-competitive manner while histone phosphatase activity was not inhibited by synthase D (8.5 unit/ml) or by phosphorylase a (12 unit/ml).
研究发现，白细胞匀浆中的合酶磷酸酶、磷酸化酶磷酸酶和组蛋白磷酸酶活性具有不同的沉降特性：合酶磷酸酶和磷酸化酶磷酸酶活性均与微粒体部分相关，而大部分组蛋白磷酸酶活性（75 - 85%）存在于胞质溶胶中。伴随微粒体部分的合酶磷酸酶、磷酸化酶磷酸酶和组蛋白磷酸酶活性很容易被0.3%的 Triton X - 100溶解。当将溶解的微粒体酶在 Sephadex G - 200上进行色谱分析时，大部分合酶磷酸酶、磷酸化酶磷酸酶和组蛋白磷酸酶活性以单峰形式迁移，其表观分子量分别对应于380 000、250 000和68 000。还获得了一个分子量为30 000的小峰，它对所有三种底物都具有磷酸酶活性。乙醇处理导致三种磷酸酶活性的溶解和解离。结果发现，尽管乙醇处理使磷酸化酶磷酸酶活性增加了4倍，但组蛋白磷酸酶活性降低了（60%），而合酶磷酸酶活性保持稳定。对17 000×g上清液进行乙醇处理时也得到了类似的结果。将乙醇处理的微粒体（或匀浆）在 Sephadex G - 200上进行色谱分析表明，对合酶D、磷酸化酶a和磷酸组蛋白的磷酸酶活性与一个分子量为30 000的物种一致。对分子量为30 000的峰进行热处理导致合酶磷酸酶和磷酸化酶磷酸酶活性解离。合酶磷酸酶被磷酸化酶a以动力学非竞争性方式抑制，而组蛋白磷酸酶活性不受合酶D（8.5单位/毫升）或磷酸化酶a（12单位/毫升）的抑制。
