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In-vitro riboflavin binding and endogenous flavins in Phycomyces blakesleeanus

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Abstract

Several types of membrane-localized flavin binding sites were investigated in sporangiophores (spph) and mycelia of Phycomyces blakesleeanus. In-vitro binding of riboflavin, riboflavin-5′-phosphate, and flavin-adenine-dinucleotide was demonstrated with unfractionated membrane preparations by means of competition of [14C]riboflavin binding. Saturation of binding was only obtained with the highly water-soluble riboflavin-5′-phosphate, but by extrapolation it was shown that riboflavin showed the highest affinity towards the binding sites (KD about 4·10-6M). The number of binding sites was estimated to be 0.7 nmol g-1 fresh-weight equivalent. Analysis of endogenous soluble flavin revealed that only riboflavin, riboflavin-5′-phosphate, and flavin-adenine-dinucleotide occurred in Phycomyces, and at a concentration of at least 1 nmol g-1 fresh-weight equivalent in entire spph. Thus, the measured binding sites could reach saturation in-vivo. In the apical part of spph to which blue-light sensitivity is restricted, the amount of soluble flavin was three-fold higher. Exclusively in this zone, heat-labile riboflavin proteins were measured at a concentration of about 3 nmol g-1 fresh-weight equivalent. The amount of covalently bound flavin was higher in spph tips than in intact spph (8 nmol and 3 nmol g-1 fresh-weight equivalent, respectively). In either case, the concentrations of the flavin-membrane complexes were higher than the theoretical calculated concentration of (anisotropic) blue-light photoreceptor in Phycomyces (Bergman et al. 1969), and their involvement in blue-light photoreception is considered.

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Abbreviations

FMN:

riboflavin-5′-phosphate

FAD:

flavin-adenine-dinucleotide

FW:

fresh weight

spph:

sporangiophore(s)

References

  1. Almog, R., Berns, D.S. (1981) A sensitive assay for proteins and biliproteins. Anal. Biochem. 114, 336–341

  2. Bergman, K., Burke, P.V., Cerda-Olmedo, E., David, C.N., Delbrück, M., Foster, K.W., Goodell, E.W., Heisenberg, M., Meissner, G., Zalokar, M., Dennison, D.S., Shropshire, W., Jr. (1969) Phycomyces. Bacteriol. Rev. 33, 99–157

  3. Cuatrecasas, P., Bennett, V. (1974) Hormone receptors and their function in cell membranes. In: Perspectives in membrane biology, pp. 439–453, Estrada-O, S., Gitler, C., eds. Academic Press, New York San Francisco London

  4. Hakenbeck, R., Kohiyama, M. (1982) Labelling of pneumococcal penicillin-binding proteins with [3H]propionyl-ampicillin. A rapid method for monitoring penicillin-binding activity. FEMS Microbiol. Lett. 14, 241–245

  5. Hemmerich, P. (1976) The present status of flavin and flavocoenzyme chemistry. Progr. Chem. Org. Nat. Prod. 33, 451–527

  6. Hemmerich, P., Schmidt, W. (1980) Blue light reception and flavin photochemistry. In: Photoreception and sensory transduction in aneural organisms, pp. 271–283, Lenci, F., Colombetti, G., eds. Plenum Press, New York London

  7. Hertel, R. (1980) Phototropism of lower plants. In. Photoreception and sensory transduction in aneural organisms, pp. 89–105, Lenci, F., Colombetti, G., eds. Plenum Press, New York London

  8. Hertel, R., Jesaitis, A.J., Dohrmann, U., Briggs, W.R. (1980) In vitro binding of riboflavin to subcellular particles from maize coleoptiles and Cucurbita hypocotyls. Planta 147, 312–319

  9. Jesaitis, A.J. (1974) The linear dichroism and orientation of the Phycomyces photopigment. J. Gen. Physiol. 63, 1–21

  10. Kearney, E.B., Pearl, M., Lipsik, J., Goldenberg, J. (1980) An unusual flavokinase from Bacillus subtilis. In: Flavins and flavoproteins, pp. 603–608, Yagi, K., Yamano, T., eds. Japan Scientific Society Press Tokyo

  11. Otto, M.K., Jayaram, M., Delbrück, M. (1981) Replacement of riboflavin by an analogue in the blue light photoreceptor of Phycomyces. Proc. Natl. Acad. Sci. USA. 78, 266–269

  12. Pearl, M., Kearney, E.B., Singer, T.B., (1976) Transport of riboflavin into cells. In: Flavins and flavoproteins, pp. 754–761, Singer, T.P., ed. Elsevier, Amsterdam

  13. Pollock, J.A., Sullivan, D.T., Lipson, E.D. (1983) Two dimensional gel electrophoresis of Phycomyces photoreceptor mutants. Biophys. J. 41, 24

  14. Presti, D., Delbrück, M. (1978) Photoreceptors for biosynthesis, energy storage and vision. Plant Cell Environ. 1, 81–100

  15. Presti, D., Hsu, W.J., Delbrück, M. (1977) Phototropism in Phycomyces mutant lacking β-carotene. Photochem. Photobiol. 26, 403–405

  16. Raugei, G., Dohrmann, U., Pohl, U., Russo, V.E.A. (1982) Kinetics of photoaccumulation of β-carotene in Phycomyces blakesleeanus. Planta 155, 296–300

  17. Ray, P.M., Dohrmann, U., Hertel, R. (1977) Characterization of naphthaleneacetic acid binding to receptor sites on cellular membranes of maize coleoptile tissue. Plant Physiol. 59, 357–364

  18. Russo, V.E.A., Galland, P. (1980) Sensory physiology of Phycomyces blakesleeanus. Struct. Bonding (Berlin) 41, 73–110

  19. Schmidt, W. (1980) Physiological blue light reception. Struct. Bonding (Berlin) 41, 1–44

  20. Schmidt, W., Thomson, K.-St., Butler, W.L. (1977) Cytochrome b in plasma membrane enriched fractions from several photoresponsive organisms. Photochem. Photobiol. 26, 407–411

  21. Singer, T.P., Edmondson, D.E. (1980) Structure, properties and determination of covalently bound flavins. Methods Enzymol. 66, 253–264

  22. Song, P.-S. (1980) Primary photophysical and photochemical reactions: theoretical background and general introduction. In: Photoreception and sensory transduction in aneural organisms, pp. 189–210, Lenci, F., Colombetti, G., eds. Plenum Press, New York London

  23. Song, P.S., Moore, T.A. (1974) On the photoreceptor pigment for phototropism and phototaxis: is a carotenoid the most likely candidate? Photochem. Photobiol. 19, 435–441

  24. Yagi, K. (1962) Chemical determination of flavins. Methods Biochem. Anal. 10, 319–356

  25. Zaichkin, E.I., Orlova, S.A., Fikhte, B.A. (1975) Study of dynamics of formation of surface membrane in isolated microdoplets of cytoplasm of Phycomyces blakesleeanus. Dokl. Akad. Nauk SSSR 225, 1187–1189

  26. Zenk, M.H. (1967) Untersuchungen zum Phototropismus der Avena-Koleoptile. II. Pigmente. Z. Pflanzenphysiol. 56, 122–140

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Dohrmann, U. In-vitro riboflavin binding and endogenous flavins in Phycomyces blakesleeanus . Planta 159, 357–365 (1983). https://doi.org/10.1007/BF00393175

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Key words

  • Blue light photoreceptor
  • Flavin
  • Phycomyces
  • Sporangiophore