An enzyme generates a Lineweaver-Burk plot with a slope of m. If the enzyme's Michaelis constant K_m is known, which expression yields the maximum velocity V_max of the enzyme-catalyzed reaction?

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11ecba2d_0f13_725a_a3bf_1188df301f68_MD0008_00 Lineweaver-Burk plots are derived from a rearrangement of the Michaelis-Menten equation. They are double-reciprocal plots in which the reciprocal of reaction velocity (1/V₀) is plotted on the y-axis as a function of the reciprocal of substrate concentration (1/[S]) on the x-axis. The general form of the Lineweaver-Burk equation is 11ecba2d_0f13_725b_a3bf_b5283e8b5f78_MD0008_00 1V0=KmVmax1[S]+1Vmax This equation converts Michaelis-Menten data into a linear plot (y = mx + b) in which the slope (m) is K_m/V_max and the y-intercept (b) is 1/V_max. Therefore, the relationship of the slope to K_m and V_max can be written as 11ecba2d_0f13_725c_a3bf_3f99947f8561_MD0008_00 m=KmVmax If the Michaelis constant K_m is known, then the value of V_max can be determined by solving for it algebraically. First, both sides of the equation are multiplied by V_max to give 11ecba2d_0f13_996d_a3bf_5ffea344c676_MD0008_00 m×Vmax=Km Then both sides are divided by m to yield V_max in terms of K_m and m: 11ecba2d_0f13_996e_a3bf_79f4a92d448f_MD0008_00 Vmax=Kmm (Choice B) K_m should be divided by m, not multiplied, to yield V_max. (Choice C) m/K_m is the reciprocal of V_max. V_max is equal to K_m/m. (Choice D) K_m should be divided by m, not added to it, to yield V_max. Educational objective: The Lineweaver-Burk equation is a rearrangement of the Michaelis-Menten equation that converts enzyme kinetic plots into linear plots. The slope of a Lineweaver-Burk plot is equal to K_m/V_max and the y-intercept is equal to 1/V_max.

An Enzyme Generates a Lineweaver-Burk Plot with a Slope of M