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Cost in Gibbs free energy of formation of a complex between protein and ligand

Range	~15 - 20 kJ/mol
Organism	Generic
Reference	Klebe G. Applying thermodynamic profiling in lead finding and optimization. Nat Rev Drug Discov. 2015 Feb14(2):95-110. doi: 10.1038/nrd4486. p.96 middle columnPubMed ID25614222
Primary Source	Murray, C. W. & Verdonk M. L. The consequences of translational and rotational entropy lost by small molecules on binding to proteins. J. Comput. Aided Mol. Design 16, 741–753 (2002). abstractPubMed ID12650591
Comments	"Before the formation of a complex, the protein and ligand are separately solvated and move freely in the bulk solvent phase. When these two independent 'particles' merge into one, forming the complex, they sacrifice rotational and translational degrees of freedom as two independent particles are reduced to one [ref 28]. This entropic loss is associated with a cost in the Gibbs free energy which has been calculated to be approximately 15–20 kJ per mol [primary source]. Experimentally, this value has been confirmed by Nazare et al. [ref 30] and Borsi et al. [ref 31], who studied the coupling of two non-overlapping fragments binding to factor Xa or matrix metalloproteinase 12 (MMP12)."
Entered by	Uri M
ID	111401