Batke J, Asbóth G, Lakatos S, Schmitt B, Cohen R
Eur J Biochem. 1980 Jun;107(2):389-94. doi: 10.1111/j.1432-1033.1980.tb06041.x.
A threefold decrease in specific activity of glycerol-3-phosphate dehydrogenase was found on going from 800 nM to 10 nM enzyme concentration. According to ultracentrifugal analyses the dimeric glycerol-3-phosphate dehydrogenase (molecular weight 78,000) dissociates into monomers in the equilibrium mixture of its substrates and products. The concentration-dependent decrease in the specific activity is interpreted as a consequence of subunit dissociation and the estimated dissociation constants are 0.7 micro M and 3.5 micro M at 38 degrees C and 20 degrees C respectively. According to active-enzyme-band centrifugation experiments and kinetic analysis aldolase forms a complex with glycerol-3-phosphate dehydrogenase and this complex formation influences the specific activity of the dehydrogenase. The interaction between glycerol-3-phosphate dehydrogenase and aldolase can provide a regulatory mechanism at the branching point of glycolytic and lipid metabolic pathways.
当酶浓度从800 nM降至10 nM时，甘油-3-磷酸脱氢酶的比活性降低了三倍。根据超速离心分析，二聚体甘油-3-磷酸脱氢酶（分子量78,000）在其底物和产物的平衡混合物中解离成单体。比活性随浓度的降低被解释为亚基解离的结果，在38℃和20℃时估计的解离常数分别为0.7 μM和3.5 μM。根据活性酶带离心实验和动力学分析，醛缩酶与甘油-3-磷酸脱氢酶形成复合物，这种复合物的形成影响脱氢酶的比活性。甘油-3-磷酸脱氢酶和醛缩酶之间的相互作用可以在糖酵解和脂质代谢途径的分支点提供一种调节机制。
