Quenching of the fluorescence of pterin derivatives by anions
Tóm tắt
Steady-state and time-resolved studies of the fluorescence of pterins in aqueous solutions in the presence of different anions have been performed using the single-photon counting technique. In the pH range between 3 and 13, most pterins exist in a protonated and a deprotonated form. Results obtained for both acid and basic forms of five compounds belonging to the pterin family (pterin, 6-carboxypterin, 6-formylpterin, biopterin and neopterin) show that the fluorescence of the acid forms is dynamically quenched by phosphate and acetate, and the corresponding bimolecular rate constants of fluorescence quenching (kq) are reported. These results are of importance from the technical and analytical points of view because measurements of the fluorescence of pterin derivatives for a variety of purposes are often performed in the presence of salts, especially buffers, and significant quenching of the pterin fluorescence by the buffer might lead to errors in interpretation and erroneous conclusions. No quenching of the fluorescence of the acid forms by chloride, sulfate or nitrate was detected. The fluorescence of the basic forms was either not quenched by anions or any such quenching was negligible in comparison with that observed for the acid forms.
Tài liệu tham khảo
G. Hopkins, in Chemistry and Biology of Pteridines and Folates, ed. J. E. Ayling, M. G. Nair and C. M. Baugh, Plenum Press, New York, 1993, p. 1.
C. A. Nichol, G. K. Smith, D. S. Duch, Biosynthesis and metabolism of tetrahydrobiopterin and molybdopterin, Annu. Rev. Biochem. 1985, 54, 729–764.
M. A. Marletta, in Chemistry and Biology of Pteridines and Folates, ed. J. E. Ayling, M. G. Nair and C. M. Baugh, Plenum Press, New York, 1993, p. 281.
J. M. Hevel, M. A. Marletta, Macrophage nitric oxide synthase: relationship between enzyme-bound tetrahydrobiopterin and synthase activity, Biochemistry 1992, 31, 7160–7165.
D. Fuchs, A. Hausen, G. Reibnegger, E. R. Werner, M. P. Dierich, H. Wachter, Neopterin as marker for activated cell-mediated immunity, Immunol. Today 1988, 9, 150–155.
C. Huber, J. Troppmair, H. Rokos, H. C. Curtius, Neopterin heute, Dtsch. Med. Wochenschr. 1987, 112, 107–113.
P. Galland, H. Senger, The role of pterins in the photoreception and metabolism of plants, Photochem. Photobiol. 1988, 48, 811–820.
H. Ninnemann, Some aspects of blue light research during the last decade, Photochem. Photobiol. 1995, 61, 22–31.
P. Heelis, S. T. Kim, T. Okamura, A. Sancar, The photorepair of pyrimidine dimers by DNA photolyase and model system, J. Photochem. Photobiol., B 1993, 17, 219–228.
J. E. Hearst, The structure of photolyase: using photon energy for DNA repair, Science 1995, 268, 1858–1859.
K. Ito, S. Kawanishi, Photoinduced hydroxylation of deoxyguanosine in DNA by pterins: sequence specificity and mechanism, Biochemistry 1997, 36, 1774–1781.
C. Lorente, A. H. Thomas, L. S. Villata, D. Hozbor, A. Lagares, A. L. Capparelli, Photoinduced cleavage of plasmid DNA in the presence of pterin, Pteridines 2000, 11, 100–105.
K. V. Neverov, E. A. Mironov, T. A. Lyudnikova, A. A. Krasnovsky, M. S. Kritsky, Phosphorescence analysis of the triplet state of pterins in connection with their photoreceptor function in biochemical systems, Biokhimiya (Moscow) 1996, 61, 1627–1636.
A. H. Thomas, C. Lorente, A. L. Capparelli, C. G. Martínez, A. M. Braun, E. Oliveros, Singlet oxygen (1Δg) production by pterin derivatives in aqueous solutions, Photochem. Photobiol. Sci. 2003, 2, 245–250.
C. Chahidi, M. Aubailly, A. Momzikoff, M. Bazin, R. Santus, Photophysical and photosensitizing properties of 2-amino-4-pteridinone: a natural pigment, Photochem. Photobiol. 1981, 33, 641–649.
A. H. Thomas, C. Lorente, A. L. Capparelli, M. R. Pokhrel, A. M. Braun, E. Oliveros, Fluorescence of pterin, 6-formylpterin, 6-carboxypterin and folic acid in aqueous solutions: pH effects, Photochem. Photobiol. Sci. 2002, 1, 421–426.
A. Albert, Quantitative studies of the acidity of naturally occurring substances for trace metals, Biochem. J. 1953, 54, 646–654.
V. D. Monópoli, A. H. Thomas, A. L. Capparelli, Kinetics and equilibrium study of nickel(II) complexation by pterin and 6-carboxypterin, Int. J. Chem. Kinet. 2000, 32, 231–237.
A. H. Thomas, M. R. Féliz, A. L. Capparelli, Equilibrium and kinetic studies of cobalt(II) complexation by folic acid, Transition Met. Chem. 1996, 21, 317–321.
A. H. Thomas, G. Suárez, F. M. Cabrerizo, R. Martino, A. L. Capparelli, Study of the photolysis of folic acid and 6-formylpterin in acid aqueous solutions, J. Photochem. Photobiol., A 2000, 135, 147–154.
V. Herbert and J. R. Bertino, Folic acid, in The Vitamins, ed. P. György and W. N. Pearson, Academic Press, New York, 1967, vol. 7, ch. 8.
J. J. McCormac and R. A. Newman, Chromatographic studies of folic acid and related compounds, in Modern Chromatographic Analysis of the Vitamins, ed. A. P. De Leenheer, W. E. Lambert and M. G. M. De Ruyter, Marcel Dekker Inc., New York, 1987, ch. 6.
M. E. Hawkins, W. Pfleiderer, F. M. Balis, D. Porter, J. R. Knutson, Fluorescence properties of pteridine nucleoside analogs as monomers and incorporated into oligonucleotides, Anal. Biochem. 1997, 244, 86–95.
M. E. Hawkins, W. Pfleiderer, A. Mazumder, Y. G. Pommier, F. M. Balis, Incorporation of a guanosine analog into oligonucleotides and its application to a real time assay for the HIV-1 integrase 3-processing reaction, Nucleic Acids Res. 1995, 23, 2872–2880.
M. E. Hawkins, W. Pfleiderer, O. Jungmann, F. M. Balis, Synthesis and fluorescence characterization of pteridine adenosine nucleoside analogs for DNA incorporation, Anal. Biochem. 2001, 298, 231–240.
K. R. Gopidas, A. R. Leheny, G. Caminati, N. J. Turro, D. A. Tomalia, Photophysical investigation of similarities between starburst dendrimers and anionic micelles, J. Am. Chem. Soc. 1991, 113, 7335–7342.
D. Ben-Avraham, L. S. Schulman, S. H. Bossman, C. Turro, N. J. Turro, Luminescence quenching of ruthenium(II)-tris(phenanthroline) by cobalt(III)-tris(phenanthroline) bound to the surface of starburst dendrimers, J. Phys. Chem. B 1998, 102, 5088–5093.
D. F. Eaton, in Handbook of Organic Photochemistry, ed. J. C. Scaiano, CRC Press, Boca Raton, 1989, ch. 8.
S. R. Meech, D. Phillips, Photophysics of some common fluorescence standards, J. Photochem. 1983, 23, 193–217.
J. R. Lakowicz, Principles of Fluorescence Spectroscopy, Plenum Press, New York, 1983, ch. 9.
Handbook of Chemistry and Physics, ed. D. R. Lide, CRC Press, Boca Raton, 1995, sect. 8.
A. H. Thomas, G. Suárez, F. M. Cabrerizo, A. L. Capparelli, Photochemistry of 6-formylpterin in alkaline medium, Helv. Chim. Acta 2001, 84, 3849–3860.
G. Suárez, F. M. Cabrerizo, C. Lorente, A. H. Thomas, A. L. Capparelli, Study of the photolysis of 6-carboxypterin in acid and alkaline aqueous solutions, J. Photochem. Photobiol., A 2000, 132, 53–57.
R. Baur, M. Kappel, R. Mengel and W. Pfleiderer, in Chemistry and Biology of Pteridines, ed. R. L. Kisliuk and G. M. Brown, Elsevier/North Holland, New York, 1979, p. 13.
W. Pfleiderer, M. Kappel and R. Baur, in Biochemical and Clinical Aspects of Pteridines, Vol. 3, ed. W. Pfleiderer, H. Wachter and H. Ch. Curtius, Walter de Gruyter & Co., Berlin/New York, 1984, p. 3.