PMID: 17567736

Authors:

Ziolkowska NE, Shenoy SR, O'Keefe BR, Wlodawer A

Title:

Crystallographic studies of the complexes of antiviral protein griffithsin with glucose and N-acetylglucosamine.

Journal:

Protein Sci. 2007 Jul;16(7):1485-9. Epub 2007 Jun 13.

Abstract:

Crystal structures of complexes of an antiviral lectin griffithsin (GRFT) with glucose and N-acetylglucosamine were solved and refined at high resolution. In both complexes, all six monosaccharide-binding sites of GRFT were occupied and the mode of binding was similar to that of mannose. In our previous attempts to obtain a complex with N-acetylglucosamine by soaking, only a single site was occupied; thus, cocrystallization was clearly superior despite lower concentration of the ligand. Isothermal titration calorimetric experiments with N-acetylglucosamine, glucose, and mannose provided enthalpic evidence of distinct binding differences between the three monosaccharides. A comparison of the mode of binding of different monosaccharides is discussed in the context of the antiviral activity of GRFT, based on specific binding to high-mannose-containing complex carbohydrates found on viral envelopes.