Some physicochemical aspects of oligosaccharide binding to concanavalin A and wheat germ agglutinin
- 35 Downloads
The binding of fluorescently labelled carbohydrates to concanavalin A and wheat germ agglutinin was studied at equilibrium and by the stopped-flow and temperature jump relaxation methods. Ligand were mainly die 4-methylumbelliferyl glycosides of α (1 → 2)-linked manno-oligosaccharides and of β (1 → 4)-linked chito oligosaccharides as limited homologous series. They offer distinct advantages, parti cularly for kinetic studies.
Enthalpie and kinetic considerations suggest that concanavalin A specifically binds a single mannopyranosyl group in α (1 →2)-linked manno-oligosaccharides. This occurs preferentially at the non-reducing end. Glycosylation of a carbohydrate withe.g. an aryl group does not afect die binding kinetics and for all carbohydrates the association rate is comparable but relatively slow, which indicates that a common process is involved in the binding of all carbohydrates to concanavalin A. The affinity of a carbohydrate for concanavalin A is determined by the dissociation-rate parameter, resulting in a longer residence time for a better ligand.
Interaction of chito-oligosaccharides with wheat germ agglutinin is complex. With the larger members of the 4-methylumbelliferyl chito-oligosaccharides, binding studies were only possible at low fractional saturation to avoid formation of unsoluble complexes. The binding kinetics of wheat germ agglutinin are faster than with concanavalin A and are consistent with a wheat germ agglutinin binding region composed of two adjacent subsites. For binding of the monoside as well as the bioside, two consistent kinetic models apply. They have common that for each ligand there exist two complexes with comparable population.
KeywordsConcanavalin A wheat germ agglutinin fluorescence difference absorption temperature-jump stopped-flow
- Con A
wheat germ agglutinin
Unable to display preview. Download preview PDF.
- Allen, A. K., Neuberger, A. and Sharon, N. 1973Biochem J.,155, 127.Google Scholar
- Bernasconi, C. F. (1976)Relaxation Kinetics, (New York: Academic Press) p. 22.Google Scholar
- Brewer, C. F., Marcus, D., Grollman, A. P. and Sternlicht, H. (1974) inLysozyme, eds. F. Osserman, et. al., (New York: Academic Press) p. 239.Google Scholar
- Clegg, R. M., Loontiens, F. G., Van Landschoot, A., Sharon, N., De Bruyne, C. K. and Jovin, T. M. 1980Arch. Int. Physiol. Biochem.,88, B69.Google Scholar
- De Boeck, H. (1980)Licentiaatsthesis, University of Ghent, Belgium.Google Scholar
- Goldstein, I. J., Hammarström, S. and Sundblad, G. (1975)Biochim. Biphys. Acta,405, 53.Google Scholar
- Grimaldi, J. J. and Sykes, B. D. (1975)Biol. Chem.,250, 1618.Google Scholar
- Harrington, P. C, Moreno, R. and Wilkins, R. G. (1981)Isr. J. Chem.,21, 48.Google Scholar
- Midoux, P. (1980)Interactions: protéine-sucre;étude spectroscopique des interactions entre lα lectine du gerne de blé (WGA) etdes darivus de Iα N-acetyl-D-glucosamine, Orléans, Thèse 3ème cycle, Orléans.Google Scholar
- Pecht, I. and Lancet, D. (1977) inChemical Relaxations in Molecular Biology, eds I. Pecht and R. Rigler, (Berlin: Springer Verlag) p. 306.Google Scholar
- Urdea, M. S., Christie, D. J., Munske, G. R., Magnuson, J. A. and Legg, J. I. (1979)Biochem. Biophys. Res. Commun.,95,1043.Google Scholar
- Van Landschoot,A. (1978)Binding van Oligosacchariden en hun fluorescerende 4-methylumbelliferylderivaten op concanavaline A en op het lectine uit tarwekiemen;evenwichtsstudies, ‘stopped-flow’en temperatuursprongs-relaxatie kinetiek, Ghent Ph. D, thesis.Google Scholar
- Van Landschoot, A., Clegg, R. M., Loontiens, F. G. and Sharon, N. (1978b)9th Intl. Symp. Carbohydr. Chem. London, Abstract D18.Google Scholar