Catalytic Power Enzymes are incredibly efficient TABLE 8.1 Rate enhancement by selected enzymes Uncatalyzed Catalyzed Rate Nonenzymatic rate rate enhancement Enzyme half-life (kun s-1) (kcat s-1) (kcat/kun) OMP decarboxylase 78,000,000 years 2.8×10-16 39 1,4×1017 Staphylococcal nuclease 130.000 years 1.7×10-13 95 5.6×1014 AMP nucleosidase 69,000 years 1.0×10-11 60 6.0×1012 Carboxypeptidase A 7.3 years 3.0×10-9 578 1.9×1010 Ketosteroid isomerase 7 weeks 1.7×10-7 66,000 3.9×10日 Triose phosphate isomerase 1.9 days 4.3×10-6 4,300 1.0×109 Chorismate mutase 7.4 hours 2.6×10-5 50 1.9×106 Carbonic anhydrase seconds 1.3×10-1 1×106 7.7×106 Abbreviations:OMP,orotidine monophosphate:AMP.adenosine monophosphate. Source:After A.Radzicka and R.Wofenden.Science 267 (1995):90-93.Enzymes are incredibly efficient Catalytic Power