A FTIR spectroscopy evidence of the interactions between wheat germ agglutinin and N-acetylglucosamine residues

Wheat germ agglutinin (WGA), a lectin binding a N-acetyl-D-neuraminic acid (NeuNAc) and/or N-acetyl-D-glucosamine (GlcNAc) group, mas studied by Fouri er transform infrared (FTIR) spectroscopy, Deconvolution of the FTIR spectr um of WGA alone indicated the presence of fem a-helices and beta-sheets, in contrast to many other lectins, These results agree with previous WGA crys tal data, The WGA conformational changes, induced by GlcNAc-bearing liposom es or GlcNAc oligomers, were studied by infrared differential spectroscopy, The GlcNAc binding to WGA resulted in a decrease of turns and alpha-helice s and a concomitant appearance of beta-sheets, inducing more or less peptid ic N-H deuteration, (C) 1999 Federation of European Biochemical Societies.