大鼠下颌下腺中果糖-2,6-二磷酸对磷酸果糖激酶的依赖性调节。

Fructose 2,6-bisphosphate-dependent regulation of phosphofructokinase in rat submandibular gland.

Sugiya H, Fujita Y, Fukushima E, Yamazaki T, Furuyama S

Department of Physiology, Nihon University School of Dentistry, Matsudo, Chiba, Japan.

Int J Biochem. 1988;20(3):237-41. doi: 10.1016/0020-711x(88)90347-3.

Abstract

Regulation of phosphofructokinase in rat submandibular gland was non-Michaelis-Menten type at physiological pH. 2. At pH 7.3, ATP played a dual role on phosphofructokinase acting as a substrate and inhibitor at high concentration of ATP. 3. The activator of phosphofructokinase was present in cytosol fraction, and its properties were resemble to those of fructose 2,6-bisphosphate. 4. Both the activator and authentic fructose 2,6-bisphosphate relieved the inhibition of phosphofructokinase by ATP, and increased the affinity for fructose 6-phosphate. 5. Concentration of fructose 2,6-bisphosphate in rat submandibular gland was 8.22 nmol/g tissue, and which was about the half of that in liver. 6. Phosphofructokinase in rat submandibular gland was found to be regulated synergistically by ATP, fructose 6-phosphate and fructose 2,6-bisphosphate.

摘要

在生理pH值下，大鼠下颌下腺中磷酸果糖激酶的调节是非米氏-门坦类型。2. 在pH 7.3时，ATP对磷酸果糖激酶发挥双重作用，在高浓度ATP时作为底物和抑制剂。3. 磷酸果糖激酶的激活剂存在于胞质溶胶部分，其性质类似于果糖2,6-二磷酸。4. 激活剂和 authentic果糖2,6-二磷酸均减轻了ATP对磷酸果糖激酶的抑制，并增加了对果糖6-磷酸的亲和力。5. 大鼠下颌下腺中果糖2,6-二磷酸的浓度为8.22 nmol/g组织，约为肝脏中浓度的一半。6. 发现大鼠下颌下腺中的磷酸果糖激酶受ATP、果糖6-磷酸和果糖2,6-二磷酸的协同调节。（注：原文中“authentic”可能有误，推测应为“authentic fructose 2,6-bisphosphate”即“真的果糖2,6-二磷酸” ，这里按字面翻译存疑）