Comprehensive conformational study of key interactions involved in zearalenone complexation with beta-D-glucans.
The beta-D-glucans from the cell wall of Saccharomyces cerevisiae have shown in vitro affinity for zearalenone. For this reason, their utilization as dietary adsorbent, to reduce the bioavailability of zearalenone, is of practical interest. Our study used powerful devices to elucidate the spatial conformation and molecular sites of interaction between ZEN and beta-D-glucans. In this respect, 1H NMR spectroscopy implicated the hydroxyl groups of the phenol moiety of zearalenone in the complexation by laminarin, a pure beta-(1,3)-D-glucan. X-ray diffraction determined that laminarin displays the conformation of a single-helix with six beta-D-glucopyranose residues per turn. At this stage, molecular modeling was useful to locate the interaction sites and to propose highly probable complexes of zearalenone with laminarin fragment. Interestingly, the beta-(1,3)-D-glucan chain favors a very stable intra-helical association with zearalenone, nicely stabilized by beta-(1,6)-D-glucans side chains. Both hydrogen bonds and van der Waals interactions were precisely identified in the complex and could thus be proposed as driving interactions to monitor the association between the two molecules.
Yiannikouris
Alexandros
A
UR1213 INRA, Unité de Recherches sur les Herbivores, Centre de Clermont-Theix, 63122 St-Genès Champanelle, France.
André
Gwénaëlle
G
Buléon
Alain
A
Jeminet
Georges
G
Canet
Isabelle
I
François
Jean
J
Bertin
Gérard
G
Jouany
Jean-Pierre
JP
D004187:Disaccharides / Q000737:chemistry; D005936:Glucans / Q000737:chemistry; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D008958:Models, Molecular; D011108:Polymers / Q000737:chemistry; D011487:Protein Conformation; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D012984:Software; D014961:X-Ray Diffraction; D015025:Zearalenone / Q000737:chemistry*; D047071:beta-Glucans / Q000737:chemistry*
D004187:Disaccharides; D005936:Glucans; D011108:Polymers; D047071:beta-Glucans; C014637:laminaribiose; D015025:Zearalenone