Lineweaver-Burk diagram

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In biochemistry, a Lineweaver-Burke diagram (also called a Lineweaver-Burke plot or double reciprocal plot) is a graphical representation of the Lineweaver-Burke equation of enzyme kinetics. It is a useful graphical method for analysis of the Michaelis-Menten equation:

<math>v = v_{max}\frac{[S]}{K_m + [S]} </math>

Taking the reciprocal, we have:

<math>{1 \over v} = {(K_m + [S]) \over (v_{max}[S])} = {K_m \over v_{max}} {1 \over [S]} + {1 \over v_{max}}</math>

where v is the reaction velocity, K_m is the Michaelis-Menten constant, v_max is the maximum reaction velocity, and [S] is the substrate concentration.

The Lineweaver-Burke plot is useful for rapidly identifying important terms in enzyme kinetics, such as K_m and v_max. For instance, the y-intercept of such a graph is equivalent to the inverse of v_max; the x-intercept of the graph represents -1/K_m.

As the double reciprocal plot distorts the error structure of the data it is unreliable. Most modern workers will either use non-linear regression or an alternative linear form of the Michaelis-Menten equation such as the Eadie-Hofstee plot.