Raimo G, Masullo M, Scarano G, Bocchini V
Dipartimento di Biochimica e Biotecnologie Mediche, Università di Napoli Federico II, Naples, Italy.
Biochimie. 1996;78(10):832-7. doi: 10.1016/s0300-9084(97)84335-0.
An appropriate mixture of ethylene glycol and BaCl2 enhanced the otherwise very low intrinsic GTPase activity of the elongation factor 2 isolated from the archaeon Sulfolobus solfataricus (SsEF-2). The enzymatic activity became up to 300-fold higher than that of the SsEF-2 GTPase measured in the absence of any stimulator, but remained 20-fold lower than that stimulated by ribosome. The stimulatory effect of ethylene glycol/Ba2+ was attributed to the increased affinity for GTP, probably related to a conformational change occurring in a hydrophobic region near the catalytic site.
乙二醇和氯化钡的适当混合物增强了从古生菌嗜热栖热菌(SsEF-2)中分离出的延伸因子2原本非常低的内在GTP酶活性。该酶活性比在没有任何刺激剂的情况下测得的SsEF-2 GTP酶活性高出多达300倍,但仍比核糖体刺激的活性低20倍。乙二醇/钡离子的刺激作用归因于对GTP亲和力的增加,这可能与催化位点附近疏水区域发生的构象变化有关。