shown below is a lineweaver burk plot displaying the kinetics for an enzyme catalyzed reaction with 800 pmol of enzymes in both the absence and presence of 100 concentration of an inhibitor (triangle is in presence of inhibitor and circle represents absence of inhibitor)

1. For an enzyme-catalyzed reaction, the presence of 5 nM of areversible inhibitor yields a V_max value that is 81% anda K_m value that is 78% of their respective values in theabsence of an inhibitor.

What type of inhibition is likely occurring? Give a rationalefor your answer.

2. For an enzyme-catalyzed reaction, the presence of 20

You measure the kinetics of an enzyme E as a function ofsubstrate concentration first without an inhibitor (see Table) andplot the data using the double-reciprocal (Lineweaver-Burk) plot(figure below). The enzyme concentration is maintained constant ata level of 1 �M (=10-6 M)

a. from these data, calculate Vmax and Km. Do not estimate. Showcalculation.

b. now you study enzyme inhibition by measuring enzyme kineticsin the presence of 10�M of inhibitor A or inhibitor B (separately).The lineweaver-Burk plots in the presence of these inhibitors areindicated by �+A� or �+B� in the Figure below

x-axis = 1/[S], 10⁵ M^-1

Y-axis = 1/Vo (�M/min)^-1

From these data determine the type of inhibition for:

+A .

+B .

Draw a scheme for the mechanism for the inhibition under +A and+B:

Which of the two inhibitors is more efficient at high substrateconcentrations? At low substrate concentrations? Explain yourreasoning.