On the possibility of indicating protein conformational changes via energy transfer between intrinsic fluorophores

Abstract

The rate of intermolecular energy transfer (ET) between tyrosine and triptophan residues in human serum albumin (HSA) was estimated based on the information about its structure from X-ray crystallographic data provided in protein databank (PDB) as well as from fluorescent measurements. The possibility of indicating of protein molecule’s conformational changes via intrinsic ET was shown by the analysis of PDB-structures of HSA and its complexes with different ligands. The manifestation of conformational changes of HSA in its fluorescence properties connected with the tyrosine-tryptophan ET was studied by means of steady-state spectroscopy and picosecond time-resolved technique.