Aleuria aurantia lectin family – structural insight into differences of carbohydrate binding among related proteins
Josef Houser1, Jan Komárek2, Nikola Kostlánová1, Gianluca
Cioci3, Anne Imberty4, Michaela Wimmerová1,2
1National Centre for Biomolecular Research and 2Department of Biochemistry, Faculty of Science, Masaryk University, Kotlářská 2, 611 37 Brno
3European Synchrotron Radiation Facility, 6 rue Jules Horowitz, 38043 Grenoble, France
4CERMAV-CNRS, BP53, 38041 Grenoble Cedex 9, France
Aleuria aurantia lectin (AAL) has been studied for many years. Its structure was solved in 2003 [1] revealing 6-beta propeller fold with five binding sites formed in between blades. The existence of several different binding sites leads to the difficulties in determination of their binding properties, although several studies were undertaken. [2] Interestingly, over last decade several lectins from AAL family have been identified. They all posses the same fold as AAL, but some important structural differences make them an ideal targets for structural-functional relationship study.
AAL homologue RSL from Ralstonia solanacearum is one of the strongest monosaccharide binders known. It was found out that it is able to bind ligands with subnanomolar affinity with no ions involved in the interaction. [3] Another lectin from Aspergillus fumigatus (AFL) with six different binding sites per monomer has even wider variability in carbohydrate binding than AAL itself. All these proteins are studied in our group intensively on molecular level. Thanks to the combination of crystallographic data and advanced functional studies (ITC, SPR,…) we build up a complex picture of lectin-saccharide interaction with a great potency for future medicinal and biotechnological applications.
The research has been supported by Ministry of Education of the Czech Republic (MSM0021622413, LC06030, ME08008), Grant Agency of the Czech Republic (303/09/1168) and the European Community's Seventh Framework Program under grant agreement n° 205872.
[1] M. Wimmerova, E. Mitchell, J.-F. Sanchez, C. Gautier, A. Imberty, J. Biol. Chem. 278(29) (2003), 27059–27067
[2] J. Olausson, L. Tibell, B.H. Jonsson, Glycoconjugate J. 25(8) (2008), 753-762
[3] N. Kostlanova, E.P. Mitchell, H.Lortat-Jacob, S. Oscarson, M. Lahmann, N. Gilboa-Garber, G. Chambat, M. Wimmerova, A. Imberty, J. Biol. Chem 280(30) (2005), 27839-27849