A phosphetase that hydrolyses phosphate monoesters has been Isolated from wheat thylakold membranes. Biochemical properties and inhibition kinetics of the phosphatase were Investigated using several Ions, organlc solv...A phosphetase that hydrolyses phosphate monoesters has been Isolated from wheat thylakold membranes. Biochemical properties and inhibition kinetics of the phosphatase were Investigated using several Ions, organlc solvents, and Inhlbltors. Wheat （Trltlcum aestivum L. cv. PH82-2-2） thylakold membrane phosphatase activity was activated by Mg^2＋, Ca^2＋, and Fe^2＋ and was inhibited by Mn^2＋ and Cu^2＋. For example, enzyme activity was acUvated 34.81% by 2 mmol/l. Mg^2＋, but was Inhibited 22.3% and 8.5% by 2 and 1 mmol/L Cu^2＋, respectively. Methanol, ethanol and glycol were all able to activate enzyme activity. Enzyme activity was activated 58.5%, 48.2%, and 8.7% by 40% ethanol, methanol and glycol, respectively. From these results, It can be seen that the degree of actlvetlon of the phosphetase was greatest for ethanol and the type of acUvatlon was uncompetltlve. Moreover, the activity of the thylakold membrane phosphetase was Inhibited by molybdate, vanadete, phosphate, and fluoride and the type of Inhibition produced by these elements was uncompetltlve, non-competitive, competltlve and mixed, respectively.展开更多
目的探讨PI3K抑制剂PI103对四氯化碳(CCl4)刺激的肝星状细胞(HSC)凋亡率和细胞内游离钙离子([Ca2+]i)浓度的影响,为肝纤维化的治疗提供理论基础。方法将HSC株于37℃、5%CO2孵育箱中复苏传代培养,同步化后将细胞分为3组:空白对照组、CCl...目的探讨PI3K抑制剂PI103对四氯化碳(CCl4)刺激的肝星状细胞(HSC)凋亡率和细胞内游离钙离子([Ca2+]i)浓度的影响,为肝纤维化的治疗提供理论基础。方法将HSC株于37℃、5%CO2孵育箱中复苏传代培养,同步化后将细胞分为3组:空白对照组、CCl4组、CCl4+PI3K抑制剂组。用锚定蛋白V异硫氰酸荧光素/碘化丙啶(Annexin V FITC/PI)双标记染色,通过流式细胞仪观察各组细胞凋亡情况;以钙离子荧光探针(Fluo-3AM)为[Ca2+]i荧光指示剂负载细胞,用激光扫描共聚焦显微镜观察[Ca2+]i变化情况。结果 CCl4作用后,HSC凋亡率的变化不明显(P>0.05),但[Ca2+]i荧光强度明显增强(P<0.05)。PI3K抑制剂作用于经CCl4刺激的HSC后,细胞凋亡率增加(P<0.05),[Ca2+]i荧光强度减弱(P<0.05)。结论 PI3K抑制剂PI103可增加HSC的凋亡率,降低[Ca2+]i浓度。展开更多
文摘A phosphetase that hydrolyses phosphate monoesters has been Isolated from wheat thylakold membranes. Biochemical properties and inhibition kinetics of the phosphatase were Investigated using several Ions, organlc solvents, and Inhlbltors. Wheat （Trltlcum aestivum L. cv. PH82-2-2） thylakold membrane phosphatase activity was activated by Mg^2＋, Ca^2＋, and Fe^2＋ and was inhibited by Mn^2＋ and Cu^2＋. For example, enzyme activity was acUvated 34.81% by 2 mmol/l. Mg^2＋, but was Inhibited 22.3% and 8.5% by 2 and 1 mmol/L Cu^2＋, respectively. Methanol, ethanol and glycol were all able to activate enzyme activity. Enzyme activity was activated 58.5%, 48.2%, and 8.7% by 40% ethanol, methanol and glycol, respectively. From these results, It can be seen that the degree of actlvetlon of the phosphetase was greatest for ethanol and the type of acUvatlon was uncompetltlve. Moreover, the activity of the thylakold membrane phosphetase was Inhibited by molybdate, vanadete, phosphate, and fluoride and the type of Inhibition produced by these elements was uncompetltlve, non-competitive, competltlve and mixed, respectively.
文摘目的探讨PI3K抑制剂PI103对四氯化碳(CCl4)刺激的肝星状细胞(HSC)凋亡率和细胞内游离钙离子([Ca2+]i)浓度的影响,为肝纤维化的治疗提供理论基础。方法将HSC株于37℃、5%CO2孵育箱中复苏传代培养,同步化后将细胞分为3组:空白对照组、CCl4组、CCl4+PI3K抑制剂组。用锚定蛋白V异硫氰酸荧光素/碘化丙啶(Annexin V FITC/PI)双标记染色,通过流式细胞仪观察各组细胞凋亡情况;以钙离子荧光探针(Fluo-3AM)为[Ca2+]i荧光指示剂负载细胞,用激光扫描共聚焦显微镜观察[Ca2+]i变化情况。结果 CCl4作用后,HSC凋亡率的变化不明显(P>0.05),但[Ca2+]i荧光强度明显增强(P<0.05)。PI3K抑制剂作用于经CCl4刺激的HSC后,细胞凋亡率增加(P<0.05),[Ca2+]i荧光强度减弱(P<0.05)。结论 PI3K抑制剂PI103可增加HSC的凋亡率,降低[Ca2+]i浓度。
