Efficiency of Enzyme Catalysis Beyond Paulings Postulate

Efficiency of Enzyme Catalysis Beyond Pauling s Postulate 

Let us return one more time to the Kurz equation [Eq. (2.8)], which is regarded as the quantification of Pauling s postulate that transition-state stabilization, i.e., the tighter binding between enzyme and transition state, expressed by fCT, as compared to binding between enzyme and ground state, expressed by JCS, is the source of catalytic rate enhancement. 

Identifying Ks with KM, KT approximately equals the ratio (kuncat KM)/kcat, which is the inverse of termed the proficiency which has been determined experimentally for a number of systems (see Section 2.3.4 below). If the Kurz equation captured the whole essence of enzyme catalysis, Kr should be proportional to KM)/kcat. 

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