Fluorescence quenching study on the interaction of bases of nucleic acid with electron-accepting sensitizer and serum albumin containing electron-rich tryptophan residue
Sp. Wu et al., Fluorescence quenching study on the interaction of bases of nucleic acid with electron-accepting sensitizer and serum albumin containing electron-rich tryptophan residue, RES CHEM IN, 26(7-8), 2000, pp. 727-737
Static and dynamic fluorescence quenchings of electron-accepting sensitizer
s including positive charged heterocyclics and neutral cyanoaromatics by ba
ses of nucleic acid (NB) have been investigated. It was found that NE could
act as effective electron donors to quench the fluorescence of electron-ac
cepting sensitizers. The quenchings by diffusion-controlled rate coincide w
ell with the static and dynamic Stern-Volmer correlation. On the other hand
, the diffusion-controlled fluorescence quenchings of the tryptophan (TRP)
residue in the protein enzymes, HSA and BSA, by electron-accepting ND revea
l that photochemical dual-damage of protein enzyme and thymine (THM) occur
upon u.v.-irradiation, which is characteristic of excitation wavelength-dep
endence. Therefore, the results illustrate that the lesion interactions of
NE with electron-deficient sensitizers or electron-rich TRP fluorophore-con
taining protein enzymes originate mainly from PET-initiated processes in bo
th cases.