Competitive binding

[Petr Kuzmic]

Erin and Marty Rennells wrote:
 
> Anyone have any equations describing the competitive binding of ligands
> to proteins?

See a paper currently in press:

"General Numerical Treatment of Competitive Binding Kinetics:
Application to Thrombin­Dehydrothrombin­Hirudin", Analytical
Biochemistry, in press (AB97­0614)

	http://www.biokin.com/papers/thrombin/index.shtml
	http://www.biokin.com/papers/thrombin/thrombin.pdf

and references cited in there (or "therein" as most people say in a
'real' paper).  See also

@article { Kuzm9265,
author = "P. Kuzmic and M. L. Moss and J. L. Kofron and D. H. Rich",
title = "Fluorescence displacement method for the determination 
	of receptor-ligand binding constants",
journal = "Anal. Biochem.",
volume = "205",
pages = "65-69",
year = "1992" }

for one way to avoid very complicated equations if you own a computer. 
On the other hand, for a real treat in the equation department see

@article { Wang9511,
author = "Z.-X. Wang",
title = "An exact mathematical expression for describing competitive 
	binding of two different ligand molecules to a protein molecule",
journal = "FEBS Lett.",
volume = "360",
pages = "111-114",
year = "1995" }

This last solution was obtained by solving analytically a cubic
polynomial ( ax^3 + bx^2 + cx + d = 0 ).  [Yes you can solve
analytically any polynomial up to fourth degree, but nothing above that
except special cases (Galois theorem).]  As an example problem, Mr. Wang
uses our old data from the 1992 paper.

Happy reading...

		-- Petr

_____________________________________________________________
Petr Kuzmic Ph.D. * BioKin Ltd. * Madison, WI 53708-8336, USA
pkuzmic at biokin.com * http://www.biokin.com * 608.256.1269 fax