Portillo F, Eraso P, Serrano R
Departamento de Bioquimica, Facultad de Medicina, Universidad Autonoma, Madrid, Spain.
FEBS Lett. 1991 Aug 5;287(1-2):71-4. doi: 10.1016/0014-5793(91)80018-x.
The yeast plasma membrane H+-ATPase is activated in vivo by glucose metabolism, and previous deletion analysis has shown the C-terminus of the enzyme to be involved in this regulation. Site-directed mutagenesis demonstrates that Arg909 and Thr912 at the C-terminus are important for the increase in Vmax of the ATPase induced by glucose. Other changes in kinetic parameters induced by glucose are largely independent of these amino acids. Arg909 and Thr912 form a potential phosphorylation site for calmodulin-dependent multiprotein kinase. A double mutation of Ser911 and Thr912 to Ala results in no cell growth in glucose medium and greatly reduced activation of the ATPase by glucose. Growth and activity are restored by a third mutation (Ala547----Val) at the catalytic domain, providing genetic evidence for domain interaction.
酵母质膜H⁺-ATP酶在体内通过葡萄糖代谢被激活，先前的缺失分析表明该酶的C末端参与这种调节。定点诱变表明，C末端的精氨酸909和苏氨酸912对于葡萄糖诱导的ATP酶Vmax增加很重要。葡萄糖诱导的动力学参数的其他变化在很大程度上与这些氨基酸无关。精氨酸909和苏氨酸912形成钙调蛋白依赖性多蛋白激酶的潜在磷酸化位点。丝氨酸911和苏氨酸912突变为丙氨酸的双突变导致在葡萄糖培养基中细胞无法生长，并且葡萄糖对ATP酶的激活作用大大降低。催化结构域的第三次突变（丙氨酸547→缬氨酸）恢复了生长和活性，为结构域相互作用提供了遗传学证据。
