Chapter 9, Problem 9.11P

The following data on baker’s yeast in a particular medium at 23.4°C were obtained in the presence and in the absence of an inhibitor, sulfanilamide. The reaction rate (−r_S) was measured in terms of the oxygen uptake rate $Q_{{\text{O}}_2}$, obtained as a function of oxygen partial pressure.

1. (a) Assume the rate $Q_{{\text{O}}_2}$ follows Michaelis–Menten kinetics with respect to oxygen. Calculate the $Q_{{\text{O}}_2}$ maximum (i.e., V_max), and the Michaelis–Menten constant K_M. (Ans.: V_max = 52.63 μL O₂/h · mg cells.)
2. (b) Using the Lineweaver–Burk plot, determine the type of inhibition sulfanilamide that causes the O₂ uptake to change.

* $P_{{\text{O}}_2}$ = oxygen partial pressure, mmHg; $Q_{{\text{O}}_2}$ = oxygen uptake rate, μL of O₂ per hour per mg of cells.

1. (c) List ways you can work this problem incorrectly.
2. (d) Apply one or more of the six ideas in Preface Table P-4, page xxviii, to this problem.