Information transfer among residues

In this expression r(/) is the time-dependent anisotropy, 0 the correlation times and g, the fraction of the total anisotropy (r ) which decays with this correlation time. In general we expect one component (tf,) due to rotational diffusion of the protein, and one due to torsional motions of the tryptophan residue, if such motions are significant. In proteins which contain more than a single fluorescent residue there can be energy transfer among the residues, which can appear as a component in the anisotropy decay. The timescale of energy transfer depends upon the distance and orientation between the residues, but there is little information on the timescale of energy transfer between intrinsic fluorophores in proteins. 

Long-distance interaction among residues for information transfer... 

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