Loiseau A M, Rider M H, Foret D, Rousseau G G, Hue L
Hormone and Metabolic Research Unit, Louvain University Medical School, Brussels, Belgium.
Eur J Biochem. 1988 Jul 15;175(1):27-32. doi: 10.1111/j.1432-1033.1988.tb14161.x.
6-Phosphofructo-2-kinase was purified from rat liver and hepatoma (HTC) cells. The HTC cell enzyme had kinetic properties different from those of the liver enzyme (more sensitive to inhibition by citrate and not inhibited by sn-glycerol 3-phosphate) and was not a substrate of the cyclic-AMP-dependent protein kinase. Unlike the liver enzyme, which is bifunctional and phosphorylated by fructose 2,6-[2-32P]bisphosphate, the HTC cell enzyme contained no detectable fructose-2,6-bisphosphatase activity and phosphorylation by fructose 2,6-[2-32P]-bisphosphate could not be detected. HTC cell fructose-2,6-bisphosphatase could be separated from 6-phosphofructo-2-kinase activity by purification. Antibodies raised against liver 6-phosphofructo-2-kinase did not precipitate HTC cell fructose-2,6-bisphosphatase whose kinetic properties were completely different from those of the liver enzyme.
从大鼠肝脏和肝癌(HTC)细胞中纯化出6-磷酸果糖-2-激酶。HTC细胞中的该酶具有与肝脏酶不同的动力学特性(对柠檬酸抑制更敏感且不受3-磷酸甘油抑制),并且不是环磷酸腺苷依赖性蛋白激酶的底物。与具有双功能且可被果糖2,6-[2-³²P]二磷酸磷酸化的肝脏酶不同,HTC细胞酶未检测到果糖-2,6-二磷酸酶活性,也未检测到果糖2,6-[2-³²P]二磷酸的磷酸化作用。通过纯化,HTC细胞的果糖-2,6-二磷酸酶可与6-磷酸果糖-2-激酶活性分离。针对肝脏6-磷酸果糖-2-激酶产生的抗体不能沉淀HTC细胞的果糖-2,6-二磷酸酶,其动力学特性与肝脏酶完全不同。