Beliaeva R Kh, Cheriiak V Ia, Magretova N N, Kochetov G A
Biokhimiia. 1978 Mar;43(3):545-54.
Molecular weight of native apotransketolase from baker's yeast is found to be 159000 +/- 6000 by means of sedimentation equilibrium and sedimentation-diffusion rate. The enzyme in a relatively low concentration reversibly dissociates into two subunits with molecular weight of about 80 000 at pH 7.6 and 20 degrees C. The equilibrium constant of the reaction monomer-dimer is 4.4 . 10(3) M-1. A decrease of the temperature stimulates the association of monomers into dimer, while the shift of pH 7.6 into acid or alkaline region stimulates the dissociation process. Dissociation becames irreversible at pH less than 5 and greater than 10.5.
通过沉降平衡和沉降-扩散速率法发现，面包酵母中天然脱辅基转酮醇酶的分子量为159000±6000。在pH 7.6和20℃条件下，相对低浓度的该酶可逆地解离成两个分子量约为80000的亚基。单体-二聚体反应的平衡常数为4.4×10³ M⁻¹。温度降低会促进单体缔合成二聚体，而pH从7.6向酸性或碱性区域的转变会促进解离过程。在pH小于5和大于10.5时，解离变得不可逆。
