digplanet beta 1: Athena
Share digplanet:

Agriculture

Applied sciences

Arts

Belief

Business

Chronology

Culture

Education

Environment

Geography

Health

History

Humanities

Language

Law

Life

Mathematics

Nature

People

Politics

Science

Society

Technology

Hanes–Woolf plot

In biochemistry, a Hanes–Woolf plot is a graphical representation of enzyme kinetics in which the ratio of the initial substrate concentration [S] to the reaction velocity v is plotted against [S]. It is based on the rearrangement of the Michaelis–Menten equation shown below:

{ [S] \over v } =  { [S] \over V_\max } + { K_m \over V_\max }

where Km is the Michaelis–Menten constant and Vmax is the maximum reaction velocity.

J B S Haldane stated that this method was due to Barnet Woolf.[1] It was also used by Charles Samuel Hanes, even though he does neither mention nor cite Woolf.[2] Hanes pointed out that the use of linear regression to determine kinetic parameters from this type of linear transformation is flawed, because it generates the best fit between observed and calculated values of 1/v, rather than v.

The equation can be derived from the Michaelis–Menten equation as follows:

v = {{V_\max [S]} \over {K_m + [S]}}

invert and multiply by [S]:

 {[S] \over v} = {{[S](K_m+[S])}\over{V_\max [S]}} = {{K_m+[S]}\over{V_\max }}

Rearrange:

 {[S] \over v} = {1 \over V_\max }[S] + {K_m \over V_\max }

As is clear from the equation, perfect data will yield a straight line of slope 1/Vmax, a y-intercept of Km/Vmax and an x-intercept of −Km.

Like other techniques that linearize the Michaelis–Menten equation, the Hanes–Woolf plot was used historically for rapid determination of the important kinetic parameters Km, Vmax and Vmax/Km, but it has been superseded by nonlinear regression methods that are significantly more accurate and no longer computationally inaccessible. It remains useful, however, as a means to present data graphically.

One drawback of the Hanes–Woolf approach is that neither ordinate nor abscissa represent independent variables: both are dependent on substrate concentration. As a result, the typical measure of goodness of fit, the correlation coefficient R, is not applicable.

See also[edit]

References[edit]

  1. ^ Haldane, J. B. S. (20 April 1957). "Graphical Methods in Enzyme Chemistry". Nature 179 (832). doi:10.1038/179832b0. 
  2. ^ Hanes, CS (1932). "Studies on plant amylases: The effect of starch concentration upon the velocity of hydrolysis by the amylase of germinated barley.". Biochemical Journal 26 (5): 1406–1421. PMC 1261052. PMID 16744959. 

Original courtesy of Wikipedia: http://en.wikipedia.org/wiki/Hanes–Woolf_plot — Please support Wikipedia.
This page uses Creative Commons Licensed content from Wikipedia. A portion of the proceeds from advertising on Digplanet goes to supporting Wikipedia.
73 videos foundNext > 

Enzyme Kinetics: hanes-wolf equation

For more Biochemistry videos: http://freebiologyschool.blogspot.com/p/biochemistry.html Derive a linear plot from the Michaelis Menton-Equatoin.

Enzyme Kinetics 21 Hanes Woolf Fit (In English)

Tutorial for SigmaPlot V.12 二維及三維科學繪圖統計軟體教學範例The technical graphing software choice for more than 100000 professional researchers Command, 操作指令示範; Method,...

Eadie Hofstee plot

How can we find Vmax and KM from experimental data This work is licenced under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License...

Hanes-Woolf Denklemi ve Grafiği

Eadie-Hofstee plots

In this video, the Eadie-Hofstee representation is derived from the Lineweaver-Burk one. Notice that this provides a very convenient way to obtain Km and Vma...

Eadie Hofstee plot data analysis

using an Eadie Hofstee plot to analyse enzyme data This work is licenced under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License...

Enzymatic Inhibition and Lineweaver Burke Plots

Come learn about the kinetic basis behind enzymatic inhibition. More free lessons at: http://www.khanacademy.org/video?v=ALU24yhKJZw By Ross Firestone Visit ...

Enzymes (Part 3 of 5) - Lineweaver Burk Plot - Double Reciprocal Plot

Welcome to Moof University! My name is Mahfoud, and I recently graduated from UC Riverside. I've made these videos to help students with introductory biochem...

Lineweaver Burk plot data analysis YouTube

"Lineweaver: Burk Plots" | Biochemistry with Educator.com

"Lineweaver: Burk Plots" | Biochemistry with Educator.com ▻Watch more at http://educator.com/chemistry/biochemistry/hovasapian/ Understand your Biochemistry ...

73 videos foundNext > 

We're sorry, but there's no news about "Hanes–Woolf plot" right now.

Loading

Oops, we seem to be having trouble contacting Twitter

Support Wikipedia

A portion of the proceeds from advertising on Digplanet goes to supporting Wikipedia. Please add your support for Wikipedia!

Searchlight Group

Digplanet also receives support from Searchlight Group. Visit Searchlight