Department of Biochemistry and Biophysics, University of California, Davis, California 95616.
Plant Physiol. 1971 Jan;47(1):104-8. doi: 10.1104/pp.47.1.104.
A comparison of heat stabilities and various kinetic properties between the adenosine diphosphoglucose pyrophosphorylases isolated from endosperm and embryo tissues from starchy maize seeds indicates that the adenosine diphosphoglucose pyrophosphorylase associated with the embryo is distinct from the enzyme isolated from the endosperm. The embryo enzyme is more stable to incubation for 5 minutes at 60 C while the endosperm enzyme is labile to this treatment. Both enzymes are activated by glycerate-3-P. The embryo enzyme is more sensitive to inhibition by phosphate than is the endosperm enzyme. Glycerate-3-P, which reverses the inhibition of the endosperm enzyme by phosphate, has little effect on the phosphate inhibition of the embryo enzyme. Other kinetic studies distinguish the two enzymes.
对淀粉玉米种子胚乳和胚组织中分离的腺苷二磷酸葡萄糖焦磷酸化酶的热稳定性和各种动力学性质进行比较，表明与胚相关的腺苷二磷酸葡萄糖焦磷酸化酶与从胚乳中分离的酶不同。在 60°C 孵育 5 分钟时，胚酶比从胚乳中分离的酶更稳定，而后者对这种处理不稳定。两种酶都被甘油酸-3-P 激活。与胚乳酶相比，胚胎酶对磷酸盐的抑制作用更敏感。甘油酸-3-P 可逆转磷酸盐对胚乳酶的抑制作用，但对胚胎酶的磷酸盐抑制作用影响不大。其他动力学研究也区分了这两种酶。
