The Lineweaver-Burk plot is a double reciprocal plot of which variables?

The Lineweaver-Burk plot is a double reciprocal plot of which variables?

• A. 1/v versus 1/[S]
• B. v versus [S]
• C. ln v versus [S]
• D. [S] versus Vmax

Answer: (A)

Transforming the Michaelis–Menten relationship by taking reciprocals reveals the Lineweaver–Burk form. From v = Vmax [S] / (Km + [S]), taking reciprocals gives 1/v = (Km/Vmax)(1/[S]) + 1/Vmax. So plotting 1/v versus 1/[S] yields a straight line with slope Km/Vmax and y-intercept 1/Vmax. This straight-line relationship is what defines the Lineweaver–Burk plot and it lets you estimate Vmax (from the intercept) and Km (from the slope). The original plot of v versus [S] is the hyperbolic Michaelis–Menten plot, not a double-reciprocal one, while other transforms don’t produce this simple linear form.

Transforming the Michaelis–Menten relationship by taking reciprocals reveals the Lineweaver–Burk form. From v = Vmax [S] / (Km + [S]), taking reciprocals gives 1/v = (Km/Vmax)(1/[S]) + 1/Vmax. So plotting 1/v versus 1/[S] yields a straight line with slope Km/Vmax and y-intercept 1/Vmax. This straight-line relationship is what defines the Lineweaver–Burk plot and it lets you estimate Vmax (from the intercept) and Km (from the slope). The original plot of v versus [S] is the hyperbolic Michaelis–Menten plot, not a double-reciprocal one, while other transforms don’t produce this simple linear form.