Four competitive inhibitors of an enzyme were found to exhibit the following K1 values. Which is the worst inhibitor? K1 = 7 x 10-5 M KI = 3 x 10-6 M KI = 1 x 10-4 M KI = 6 x 10-8 M

One of the hallmarks of competitive inhibition is that there is constant competition betweenthe substrate and the inhibitor for binding to the enzyme active site.a) If [inhibitor] >> [substrate], which compound “wins” (i.e., occupies the active site a greaterpercentage of the time)?b) If [substrate] >> [inhibitor], which compound “wins” (i.e., occupies the active site a greaterpercentage of the time)?

Draw Lineweaver-Burk plots for the behavior of an enzyme for which the following experimental data are available. What are the Km and Vmax values for the inhibited and uninhibited rxns? Is the inhibitor competitive or noncompetitive? [S] (M) 10,000 1 x 104 2.000-5 x 104 666673 1.5 x 10-3 400- 2.5 x 10-³ 2005x103 V, No Inhibitor (Arbitrary units) 0.026 38,461 0.092 10.87 37100 0.136 7.35 Wak 0.150 -67 0.165 6.06 L slope: 0033 yint=5057 полесте um.x=0.198 km 6.5x 10-4 0.010 0.040 25 10.086 11.63 0.120 8.33 0.142 7.04 2500 V, Inhibitor Present (Arbitrary Units) 100 ↓ $op.= .009 yint: 5.21 900x12 km: 1.73 y/o conf. V10-3 321000

The figure below shows the dependence of the enzyme's rate, v (in µM/min), as a function of substrate concentration, S (in mM). Also shown is the dependence of the rate in the presence of an inhibitor, present at a concentration of 0.2 mM. Based on this information, which of the following does this inhibitor most likely interact with? 1/v 1- 05 1/[S) O A. Michaelis complex O B. [E O C. free enzyme O D. free substrate O E. Both "A" and "B."

Chymotrypsin has the highest affinity for which of the following substrates: Table. The values of KM and kcat for some Enzymes and Substrates Enzyme Chymotrypsin Ки (М) 4.4 x 10-1 8.8 x 10-2 6.6 x 104 Kcat (S-1) 5.1 x 10-2 1.7 x 10-1 1.9 x 102 Substrate N-acetylglycine ethyl ester N-acetylvaline ethyl ester N-acetyltyrosine ethyl ester Catalase H2O2 2.5 x 10-2 1.0 x 107 Urease Urea 2.5 x 10-2 4.0 x 105 OA. N-acetylglycine ethyl ester OB. N-acetylvaline ethyl ester OC. N-acetyltyrosine ethyl ester D. Urea