EnzymeQA

EnzymeQA is an App containing about 160 revision questions and answers on enzymology. It is restricted to considering single substrate catalysis. It is hoped that it will help University undergraduate and postgraduate students revise enzymology at home or on the go. It is not an exhaustive treatment of enzymology. However, it is hoped that it will enable you to test your knowledge of key facts in enzymology. For those of you planning to determine kcat, kcat/Km and Km, EnzymeQA should help you check that you have the appropriate experimental conditions for determining catalytic constants. Likewise it should help planning to determine Ki values for competitive inhibition. If you have Michaelis-Menten data to analyze you might be interested in the Mac program MMfit which is in the Mac App store. If you have IC50 data to analyse you may also be interested in the program IC50fit in the Mac App store. Topics in EnzymeQA include: Window 1 Michaelis Menten equation. Initial rate measurements. Setting the appropriate concentrations of enzyme and substrate for determining catalytic parameters. Defining Vm, kcat, Km, kcat/Km, Ki and IC50 values. Units of catalytic constants. Order in enzyme and substrate at various substrate concentrations. Methods for determining catalytic constants. Experimental conditions for measuring catalytic constants. Activities and Specific Activities. Determining kcat/Km by complete turnover of substrates. Window 2 Competitive inhibition. Determining Ki values for competitive inhibition. Relationship between Ki and IC50 values. Brief mention of noncompetitive, mixed and uncompetitive inhibition. Window 3 pH and pH values Analysis of pH data log plots pH dependence of catalytic constants. Window 4 Elisa Enzyme cycling Spectrophotometric versus fluorescence assays FRET assays Plate reader enzyme assays Stopped flow Window 5 Transition state analogues Catalytic antibodies Ribozymes