Structure of mannose-specific snowdrop (Galanthus nivalis) lectin is representative of a new plant lectin family.
Hester, G., Kaku, H., Goldstein, I.J., Wright, C.S.(1995) Nat Struct Biol 2: 472-479
- PubMed: 7664110 
- DOI: https://doi.org/10.1038/nsb0695-472
- Primary Citation of Related Structures:  
1MSA - PubMed Abstract: 
Tetrameric Galanthus nivalis agglutinin (50,000 M(r)) belongs to a super-family of alpha-D-mannose-specific plant bulb lectins known to be potent inhibitors of retroviruses. The 2.3 A crystal structure of this lectin complexed with methyl alpha-D-mannose reveals a novel three-fold symmetric beta-sheet polypeptide fold. Three antiparallel four-stranded beta-sheets, each with a conserved mannose-binding site, are arranged as a 12-stranded beta-barrel. The tetramer displays 222 symmetry. Pairs of monomers form stable dimers through C-terminal strand exchange. The so formed hybrid beta-sheets are the sites for high affinity mannose binding in the dimer interface. Occupancy observed at corresponding sites in other beta-sheets suggests a potential for twelve sites per tetramer.
Organizational Affiliation: 
Department of Biochemistry, Virginia Commonwealth University, Richmond 23298, USA.