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Question 2 (12 marks) In a recent study, 50 µg Native human B-cell glucokinase was purified and used to determine the kinetic parameters for both D-glucose and D-mannose as substrates. In these experiments, high concentrations of the substrates were used. Km (mm) Vmax (umol.min¹.mg"¹) D-glucose 3.8 37.5 D-mannose 4.6 35.7 You decide to perform two additional experiments: The first using 4 mM of glucose and the second using 120 mM of D-mannose. In both cases you add 50 µg of purified glucokinase (as prepared in the study mentioned above). 2.1 How does the kinetics of glucokinase compare between the two experiments? Briefly explain your answer on a molecular level. (4) 2.2 Define the turnover number and give the equation used to calculate it. (2) 2.3 You want to determine how catalytically efficient the glucokinase is with D- mannose in your second experiment in 2.1. Given the enzyme concentration used was 20 μmol.mg¹, calculate the catalytic efficiency of the glucokinase for D-mannose. (2) 2.4 Show how D-mannose is converted to a glycolytic intermediate using linear reactions