Ai-Acid glycoprotein - progesterone complex

The steady-state emission spectrum of the crystals obtained with unpolarized excitation light (Fig. 8.52A) does not overlap the emission spectrum of ai- acid glycoprotein - progesterone complex obtained in solution (Fig. 8.52B), but overlaps the spectrum of hydrophobic Trp residues of the protein (Fig. 8. 53). Thus, the fluorescence observed for the crystal is characteristic of Trp residues embedded in the protein matrix. Therefore, the two Trp residues surrounded by a hydrophobic environment have the same microenvironments in crystal and in solution. 

Figure 8.51. Fluorescence excitation spectrum of a crystal of ai- acid glycoprotein -progesterone complex. A.em 335 nm. The spectrum was recorded by excitation with unpolarized light. Source Albani, J. R. 1998, Journal of Fluorescence, 8, 213-224. Authorization of reprint accorded by Kluwer Academic Publishers.

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