Lineweaver–Burk Plot Overview

• The Lineweaver-Burk equation of enzyme kinetics is represented graphically by the Lineweaver-Burk Plot (also known as the double reciprocal plot), which was first introduced by Dean Burk and Hans Lineweaver in 1934.
• It is difficult to predict Vmax and, consequently, Km from a hyperbolic plot since Vmax is reached at an infinite substrate concentration.
• Due to this challenge, Lineweaver and Burk converted the Michaelis-Menten equation into an equation for a straight line.
• The Michaelis-Menten equation is used to derive this plot, which is shown as:

Where Vmax is the maximum reaction velocity, [S] is the substrate concentration, Km is the Michaelis-Menten constant, and V is the reaction velocity (or reaction rate).

• It results in a straight line with intercepts that are equal to Km/Vmax on the x-axis and 1/Vmax on the y-axis. Km/Vmax determines the line’s slope to be equal.
• By measuring V0 at various substrate concentrations, it is possible to experimentally calculate Vmax and Km. Then 1/V0 is plotted versus 1/[S] using a double reciprocal or Lineweaver-Burk plot.
• A Lineweaver-Burk plot can be used to discriminate between competitive and non-competitive reversible enzyme inhibitors.
• This method is effective for figuring out how an inhibitor interacts with an enzyme.
• If V0 is measured when a fixed concentration of inhibitor is present and multiple substrate concentrations are present, competitive inhibition may be identified using a Lineweaver-Burk plot.
• The Lineweaver-Burk figure shows that a competitive inhibitor raises the slope of the line, changes the intercept on the x-axis (because Km is raised), but does not affect the intercept on the y-axis (since Vmax remains constant).
• Lineweaver-Burk plots may also be used to identify noncompetitive inhibition, since it affects the intercept on the y-axis (because Vmax is lowered) and increases the slope of the experimental line while maintaining the intercept on the x-axis (since Km remains constant).

Uses of Lineweaver–Burk Plot

1. Prior to widespread access to powerful computers and nonlinear regression software, it was used to calculate crucial enzyme kinetic parameters like Km and Vmax.
2. Quickly conveys a picture of the many types of enzyme inhibition.

References

• David Hames and Nigel Hooper (2005). Biochemistry. Third ed. Taylor & Francis Group: New York.
• Smith, C. M., Marks, A. D., Lieberman, M. A., Marks, D. B., & Marks, D. B. (2005). Marks’ basic medical biochemistry: A clinical approach. Philadelphia: Lippincott Williams & Wilkins.
• https://en.wikipedia.org/wiki/Lineweaver%E2%80%93Burk_plot