Question

A different experiment yields the following kinetic data Substrate] (mM)Vo (uM/min) no inhibitorVo (uM/min)+7 nM inhibitor 0.02 0.04 0.10 0.25 1.00 2.50 0.8 2.9 8.6 24 36 50 Plot the data for the kinetics of the enzyme (with and without the inhibitor) in a double reciprocal (Lineweaver-Burk) plot. Keep in mind that the x axis is 1/[S] and the y axis is 1/Vo. If you are using Excel you want to choose the (x,y) scatter plot (without a ne). You can then add a trend line (go to "chart tools" at the top and “add chart element"). You want a linear trend line. You can display the equation of the trend line if you right click on the trend line and select "format trend line". Write the equations for the two lines - Without inhibitor - With inhibitor: b. Determine Vmax (without inhibitor) and the apparent Vmax (with inhibitor). Show your work. c. Determine Km and the apparent Km. Show your work. d. What type of inhibitor is used in this experiment? Explain how you can tell

Answer 1

Plot the data using Excel. Obtain the equations for the lines.Note down the slopes and intercepts of the lines

The linear weaver - Buric equation is 1/[v_0] = km/v_max 1/[s_0] + 1/v_max____(1) where v_0 = initial velocity s_0 = initial substrate v_max = maximum velocity km = michaclis-men-ten constant y = m x + c No inhibitor: the equation is y = 0.0131 x + 0.015___(2) comparing equation (2) with (1) km/v_max = 0.0131 1/v_max = 0.015 = > v_max = 1/0.015 = 66.66 km = 0.0131 times 66.66 = 0.87 with inhibitor: the equation is y = 0.0248 x + 0.0207 comparing with equation (1) km/v_max = 0.0248 1/v_max = 0.0207 = > v_max = 48.30 km = 0.0248 times 48.30 = 1.197 b) v_max (without inhibitor) = 66.66 c) km = 0.87 apparent v_max (with inhibitor) = 48.30 apparent km = 1.197 c) type of inhibition competitive = > requires no change in v_max with addition of inhibitor = > not met by our system because v_max notequalto v_max (apparent) uncompetitive: = > requires slope should be same = our lines have different slopes = > not met mixed = > km notequalto km (apparent) v_max notequalto v_max (apparent) the condition are met by our system = > it is mixed