X-ray Crystallographic Studies of Unique Cross-Linked Lattices between Four Isomeric Biantennary Oligosaccharides and Soybean Agglutinin,
- 1 December 1997
- journal article
- research article
- Published by American Chemical Society (ACS) in Biochemistry
- Vol. 36 (49) , 15073-15080
- https://doi.org/10.1021/bi971828+
Abstract
Soybean agglutinin (SBA) (Glycine max) is a tetrameric GalNAc/Gal-specific lectin which forms unique cross-linked complexes with a series of naturally occurring and synthetic multiantennary carbohydrates with terminal GalNAc or Gal residues [Gupta et al. (1994) Biochemistry 33, 7495−7504]. We recently reported the X-ray crystal structure of SBA cross-linked with a biantennary analog of the blood group I carbohydrate antigen [Dessen et al. (1995) Biochemistry 34, 4933−4942]. In order to determine the molecular basis of different carbohydrate−lectin cross-linked lattices, a comparison has been made of the X-ray crystallographic structures of SBA cross-linked with four isomeric analogs of the biantennary blood group I carbohydrate antigen. The four pentasaccharides possess the common structure of (β-LacNAc)2Gal-β-R, where R is −O(CH2)5COOCH3. The β-LacNAc moieties in the four carbohydrates are linked to the 2,3-, 2,4-, 3,6-, and 2,6-positions of the core Gal residue(s), respectively. The structures of all four complexes have been refined to approximately 2.4−2.8 Å. Noncovalent lattice formation in all four complexes is promoted uniquely by the bridging action of the two arms of each bivalent carbohydrate. Association between SBA tetramers involves binding of the terminal Gal residues of the pentasaccharides at identical sites in each monomer, with the sugar(s) cross-linking to a symmetry-related neighbor molecule. While the 2,4-, 3,6-, and 2,6-pentasaccharide complexes possess a common P6422 space group, their unit cell dimensions differ. The 2,3-pentasaccharide cross-linked complex, on the other hand, possesses the space group I4122. Thus, all four complexes are crystallographically distinct. The four cross-linking carbohydrates are in similar conformations, possessing a pseudo-2-fold axis of symmetry which lies on a crystallographic 2-fold axis of symmetry in each lattice. In the case of the 3,6- and 2,6-pentasaccharides, the symmetry of their cross-linked lattices requires different rotamer orientations about their β(1,6) glycosidic bonds. The results demonstrate that crystal packing interactions are the molecular basis for the formation of distinct cross-linked lattices between SBA and four isomeric pentasaccharides. The present findings are discussed in terms of lectins forming unique cross-linked complexes with glycoconjugate receptors in biological systems.Keywords
This publication has 15 references indexed in Scilit:
- AMoRe: an automated package for molecular replacementActa Crystallographica Section A Foundations of Crystallography, 1994
- Biology of Animal LectinsAnnual Review of Cell Biology, 1993
- Cluster sialoside inhibitors for influenza virus: synthesis, NMR, and biological studies.Journal of the American Chemical Society, 1992
- Wheat germ agglutinin induces mating reactions in Chlamydomonas eugametos by cross-linking agglutinin-associated glycoproteins in the flagellar membrane.The Journal of cell biology, 1989
- Membrane-cytoskeleton interactions in animal cellsBiochimica et Biophysica Acta (BBA) - Reviews on Biomembranes, 1989
- Molecular Sorting in the Secretory PathwayScience, 1989
- Interactions of concanavalin A with asparagine‐linked glycopeptidesEuropean Journal of Biochemistry, 1989
- Binding and precipitating activities ofErythrina lectins with complex type carbohydrates and synthetic cluster glycosides. A comparative study of the lectins fromE. corallodendron, E. cristagalli, E. flabelliformis, andE. indicaGlycoconjugate Journal, 1989
- An efficient general-purpose least-squares refinement program for macromolecular structuresActa Crystallographica Section A Foundations of Crystallography, 1987
- Transmembrane control of the receptors on normal and tumor cellsBiochimica et Biophysica Acta (BBA) - Reviews on Biomembranes, 1976