The conversion of molecule S to product P has a Keq = 2.0. Two different, but related enzymes, A and B, can catalyze the reaction. The product P serves as an allosteric inhibitor of enzyme B, but not of enzyme A.
A. 10 mM S is placed into three separate test tubes containing, respectively, no enzyme, enzyme A, and enzyme B. Describe the endpoint of the reaction in each tube, and tell why that is the endpoint. What are the final concentrations of S and P?
B. Which tube (uncatalyzed, enzyme A, or enzyme B) will get to the endpoint first, second and third? Explain.
C. Describe the endpoint of this reaction if the enzymes A and B were found in a cell.
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