Lineweaver-Burk plot

In biochemistry, the Lineweaver-Burk plot (or double reciprocal plot) is a graphical representation of the Lineweaver-Burk equation of enzyme kinetics, described by Hans Lineweaver and Dean Burk in 1934[1].

Derivation

The plot provides a useful graphical method for analysis of the Michaelis-Menten equation:



Taking the reciprocal gives



where V is the reaction velocity, Km is the Michaelis-Menten constant, Vmax is the maximum reaction velocity, and [S] is the substrate concentration.

Use

The Lineweaver-Burk plot was widely used to determine important terms in enzyme kinetics, such as Km and Vmax before the wide availability of powerful computers and non-linear regression software, as the y-intercept of such a graph is equivalent to the inverse of Vmax; the x-intercept of the graph represents -1/Km. It also gives a quick, visual impression of the different forms of enzyme inhibition.

The double reciprocal plot distorts the error structure of the data, and it is therefore unreliable for the determination of enzyme kinetic parameters. Although it is still used for representation of kinetic data[2], non-linear regression or alternative linear forms of the Michaelis-Menten equation such as the Eadie-Hofstee plot are generally used for the calculation of parameters[3].

When used for determining the type of enzyme inhibition, the Lineweaver-Burk plot can distinguish competitive, noncompetitive and uncompetitive inhibitors. Competitive inhibitors have the same y-intercept as uninhibited enzyme (since Vmax is unaffected by competitive inhibitors the inverse of Vmax also doesn't change) but there are different slopes and x-intercepts between the two data sets. Noncompetitive inhibition produces plots with the same x-intercept as uninhibited enzyme (Km is unaffected) but different slopes and y-intercepts. Uncompetitive inhibition causes different intercepts on both the y and x axes but the same slope.

See also

Double Reciprocal Plot

Reference

1. ^ Lineweaver, H; and Burk, D. (1934). "The Determination of Enzyme Dissociation Constants". Journal of the American Chemical Society 56: 658—666. 
2. ^ Serap Doğan, Pınar Turan and Mehmet Doğan (December 2006). "Some kinetic properties of polyphenol oxidase from Thymbra spicata L. var. spicata". Process Biochemistry 41 (12): 2379-2385. doi:10.1016/j.jchromb.2006.07.006. 
3. ^ Greco, W. R. and Hakala, M. T., (1979,). "Evaluation of methods for estimating the dissociation constant of tight binding enzyme inhibitors,". J. Biol. Chem., 254,: 12104-12109,. 

External links

  • NIH guide, enzyme assay development and analysis
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Enzyme kinetics is the study of the rates of chemical reactions that are catalysed by enzymes. The study of an enzyme's kinetics provides insights into the catalytic mechanism of this enzyme, its role in metabolism, how its activity is controlled in the cell and how drugs and
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Dean Burk (March 21, 1904 - Oct. 6 1988) was an American biochemist: a co-discoverer of biotin, medical researcher, and a cancer researcher at the Kaiser Wilhelm Institute and the National Cancer Institute .

He entered the University of California at Davis at the age of 15.
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Michaelis-Menten kinetics describes the kinetics of many enzymes. It is named after Leonor Michaelis and Maud Menten. This kinetic model is valid only when the concentration of enzyme is much less than the concentration of substrate (i.e.
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Michaelis-Menten kinetics describes the kinetics of many enzymes. It is named after Leonor Michaelis and Maud Menten. This kinetic model is valid only when the concentration of enzyme is much less than the concentration of substrate (i.e.
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based on multidimensional , data, where is some nonlinear function with respect to unknown parameters θ.
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In other words, the y-intercept of a function is the point at which it intersects the line
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In other words, a "root" of a function is a value for that produces a result of zero ("0").
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..... Click the link for more information.
Michaelis-Menten kinetics describes the kinetics of many enzymes. It is named after Leonor Michaelis and Maud Menten. This kinetic model is valid only when the concentration of enzyme is much less than the concentration of substrate (i.e.
..... Click the link for more information.
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..... Click the link for more information.
Michaelis-Menten kinetics describes the kinetics of many enzymes. It is named after Leonor Michaelis and Maud Menten. This kinetic model is valid only when the concentration of enzyme is much less than the concentration of substrate (i.e.
..... Click the link for more information.
In biochemistry, an Eadie-Hofstee diagram (also Woolf-Eadie-Augustinsson-Hofstee or Eadie-Augustinsson plot) is a graphical representation of enzyme kinetics in which reaction velocity is plotted as a function of the velocity vs.
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Enzymes are proteins that catalyze (i.e. accelerate) chemical reactions.[1] In enzymatic reactions, the molecules at the beginning of the process are called substrates, and the enzyme converts them into different molecules, the products.
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The active site of an enzyme contains the catalytic and binding sites. The structure and chemical properties of the active site allow the recognition and binding of the substrate.
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In biochemistry, allosteric regulation is the regulation of an enzyme or protein by binding an effector molecule at the protein's allosteric site (that is, a site other than the protein's active site).
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EC1 Oxidoreductases/list - EC2 Transferases/list - EC3 Hydrolases/list - EC4 Lyases/list - EC5 Isomerases/list - EC6 Ligases/list
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Enzyme inhibitors are molecules that bind to enzymes and decrease their activity. Since blocking an enzyme's activity can kill a pathogen or correct a metabolic imbalance, many drugs are enzyme inhibitors. They are also used as herbicides and pesticides.
..... Click the link for more information.
Enzyme kinetics is the study of the rates of chemical reactions that are catalysed by enzymes. The study of an enzyme's kinetics provides insights into the catalytic mechanism of this enzyme, its role in metabolism, how its activity is controlled in the cell and how drugs and
..... Click the link for more information.
Michaelis-Menten kinetics describes the kinetics of many enzymes. It is named after Leonor Michaelis and Maud Menten. This kinetic model is valid only when the concentration of enzyme is much less than the concentration of substrate (i.e.
..... Click the link for more information.
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See also:
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  • List of EC numbers (EC 1)
  • List of EC numbers (EC 2)
  • List of EC numbers (EC 3)
  • List of EC numbers (EC 4)
  • List of EC numbers (EC 5)

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