[26] The Yonetani-Theorell graphical method for examining overlapping subsites of enzyme active centers

摘要: Publisher Summary This chapter describes the Yonetani-Theorell graphical method for examining overlapping subsites of enzyme active centers. It is a simple to quantitatively express relationship between two competitive inhibitors acting on an and calculate kinetic constants involved in such system. To demonstrate this graphic method, liver alcohol dehydrogenase (LADH) presented as example, where it treated single-substrate enzyme. A comparison different methods multiple inhibitions are discussed, Yagi Ozawa plots, Loewe's isobols. These plots clear interaction type given pair inhibitors, but they fail give constant (α) value directly. Whereas, when plotting combined with Dixon's plot, K EI1 , EI2 α (rate constants) graphically determined. Thus, evaluation straightforward may be more reliable.