The "Eadie-Hofstee plot" in enzyme kinetics has v/S on the X axis and v on the Y axis (v is the reaction rate and S is the substrate concentration). I've been trying to get hold of the original publication where this plot was presumably first proposed, but so far with no success.
Note that various people call this plot in various ways. For example, Segel's book [1] calls it the "Woolf-Augustinsson-Hofstee plot" (page 214, Fig. IV-22). There is no reference to Eadie. Segel's book also has an "Eadie-Scatchard" plot (no Hofstee; p. 215, Fig. IV-23), which is exactly identical, except the axes are switched: v/S on the Y axis and v on the X axis.
Interestingly, Hofstee did publish a paper [2] showing what Segel calls the "Woolf-Augustinsson-Hofstee plot". Hofstee refers to a paper by Augustinssen where presumably the "Eadie-Hofstee" plot was first used. That's the paper, ref. [3], I am trying to get hold off but I can't find it anywhere.
I did find Acta Physiologica Scandinavica online, and I did find volume 52, from 1948. But there is no "Suppl. 52" available online (note that there is no page number, just the weird "Suppl." notation).
So I now think the only way to get hold of this is to find the print edition of this journal, and see what "Suppl. 52" really is. Unfortunately none of of the libraries I have access to apparently have Acta Physiologica Scandinavica from 1948.
Is there someone reading this would could help? Just a scan of the title page and the Figure (if any) showing the "Eadie-Hofstee" plot would be perfectly sufficient.
Thanks in advance for your time!
REFERENCES
[1] Segel, I. H., Enzyme Kinetics, Wiley, New York, 1975.
[2] Hofstee, B. H. J., On the evaluation of the constants Vm and KM in enzyme reactions, Science 116 (1952) 329-331.
[3] Augustinssen, K. B. Acta Physiol. Scand. 15, Suppl. 52 (1948).
I think this paper contains an even earlier description of the V vs V/[S] plot, although it doesn't actually show such a plot.
http://www.jbc.org/content/146/1/85.full.pdf+html?sid=e077a612-2893-4ea6-b7df-73d5d0a93562
Thanks very much, Adam, for that 1942 Eadie paper. I missed that in my search before.
As you pointed out, Eadie wrote that we may "rewrite [the Michaelis-Menten equation] in the form v = Vmax - Km v / [S]0". That is in fact an equation for the straight line showing up in "Eadie-Hofstee plot" a.k.a. "Woolf-Augustinsson-Hofstee plot" a.k.a. a few other things people may have called this plot.
Also of historical interest is that Eadie is showing in Figs. 4-6 what (for whatever reason) we know call the "Dixon plot", with [I]0 on the X axis and 1/v on the Y axis. Eadie is plotting Easson and Stedman's data from 1936, which was probably the first paper where it was proposed how inhibitors work (by forming a molecular complex with the enzyme).
And actually if we look closely at the Easson & Stedman paper [1], we find that Fig. 4 is identical to the "Henderson plot", attributed to P. Henderson [2] because of a paper published 36 years later, in 1972. There are many reasons why the literature on "tight binding" inhibition, in particular, is quite confusing to many people.
In any case, thanks again...
. P.S.: In the second attached picture I added the subscript zero (signifying total or analytic concentration, as opposed to concentration at equilibrium or steady state) where we would use it normally today. Easson & Stedman used [E] for the total (analytic) concentration of the enzyme and [EI] for the equilibrium (or steady-state) concentration of the complex. A bit confusing, but this was 1936 and there were no conventions in place.
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REFERENCES
[1] Easson, L. H., and Stedman, E., The absolute activity of choline-esterase, Proc. Roy. Soc. B. 121 (1936) 142-164.
[2] Henderson, P. J., A linear equation that describes the steady-state kinetics of enzymes and subcellular particles interacting with tightly bound inhibitors, Biochem. J. 127 (1972) 321-33.
@ John: you probably mean the Science paper I am quoting as ref. [2] in my original post:
[2] Hofstee, B. H. J., On the evaluation of the constants Vm and KM in enzyme reactions, Science 116 (1952) 329-331.
That's where Hofstee says he found the idea for this plot in Augustinssen's earlier paper:
[3] Augustinssen, K. B. Acta Physiol. Scand. 15, Suppl. 52 (1948).
It's the Augustinssen paper I can't get hold of, because it's not available in the online edition of the journal ( Acta Physiol. Scand.) The problem is that there is no page number, just the notation "Suppl. 52", whatever that means.
Did you manage to get a hold of Augustinssen's paper? I tried, no luck!
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