Theoretical Basis	Usually, the value are intermediate between 1 and 0, and it is difficult to define its role in transition state quantitatively. However, through the comparison of the fractional value of , combined with large number of mutational analysis, it is possible for us to understand the structural functions of side chains in protein folding. The typical fine-structure analysis can be done by making systematic mutations in the side chains: Ile -> Val -> Ala -> Gly.
-value analysis is a basis for structure-activity relationship analysis based on protein engineering technique. Suppose a mutation destablizes the folding structure by Gu-f units of energy, the free energy change from folded state (F) to unfolded state (U). Then, if the free energy change between transition state () and unfolded state is measured, Gu-, is defined as:
A value of 1 indicates that all of one residue's interaction are formed in transition state; whereas a value close to 0 indicates that the residue does not contribute to the structure formation during transition state.
	Experimental Cases Experimental Cases II

[Home]

Danny S. Hsu 1999-2000. All rights reserved.