Blais J, Milhaud J, Bolard J, Vigny P
Laboratoire de Physique et Chimie Biomoléculaire (CNRS URA 198), Paris, France.
J Photochem Photobiol B. 1991 May;9(2):161-70. doi: 10.1016/1011-1344(91)80148-b.
The dark interaction of 5-methoxypsoralen (5-MOP) and 8-methoxypsoralen (8-MOP) with plasma membranes was studied using human erythrocyte ghosts as a model. In the presence of ghosts, modifications of the fluorescence characteristics of 5-MOP were observed, together with a quenching of the fluorescence of the tryptophan (Trp) residues of membrane proteins (up to 25%). Moreover, the appearance of an induced circular dichroism indicates that 5-MOP is located in a chiral environment. In contrast, only slight effects were observed in the case of 8-MOP. It is concluded that 5-MOP molecules are located partly within chiral protein sites of the membrane in such a way that a Förster energy transfer can occur from the Trp residues to the psoralen molecules.
