Conformation change energy transfer fluorescence

The metal-NADH distance determined by fluorescence studies on the cobalt-substituted enzyme, using binary NADH, thio-NADH, and Rose Bengal/enzyme complexes, differs from the above.242 The minimum metal-NADH distance determined by Forster calculations based on the energy transfer from bound ligand to cobalt(n) is reported as 19 A. It is thought possible that the discrepancy between this value and that determined by X-ray diffraction may be due to conformational changes in solution. 

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