![]() The second subunit (C) shows a high degree of flexibility (Bav = 41.7 A2). Complexed disaccharide is responsible for the most crucial lattice contacts, which involve only one of the two independent subunits (A). The 3.0 A structure of the cubic Man-alpha 1,3-Man-OMe complex, determined by molecular replacement and refined with X-PLOR using NCS constraints and density modification methods, is less well ordered due to a high crystal solvent content (68%). In comparison, the A-B and C-D subunit pairs have narrow interfaces (476 A2) and no direct H-bond contacts. These subunit pairs (A-D and B-C) associate tightly with a buried surface area of 1738 A2 and 33 interchain hydrogen bonds resulting from C-terminal strand exchange. The highest occupied site is located in beta-sheet I (site 1), where interactions from the dimer-related subunit contribute to complex stabilization. The 12 bound methyl-alpha-Man molecules refined with B-factors < 22 A2 and occupancies in the range of 0.5 to 1.0. The four independent subunits (A, B, C and D) of the 222 tetramer and the three four-stranded beta-sheets (I,II and III) that constitute each subunit compare closely (r.m.s. ![]() The final model of the 2.29 A orthorhombic methyl-alpha-Man complex refined with an R-factor of 0.167 (all data) includes 12 bound sugar ligands and 327 water molecules. Crystal structures of GNA complexed with methyl-alpha-D-mannose (MeMan) and mannose-alpha 1,3-D-mannose-alpha-OMe (MeMan-2) have been determined and analyzed in terms of internal structural symmetry and saccharide binding. Galanthus nivalis agglutinin (GNA, a 50 kDa tetramer) is a mannose-specific lectin of the Amaryllidaceae family of bulb lectins. ![]() Diversity, Equity, Inclusion, and Access. ![]() Citation, Usage, Privacy Policies, Logo.Biologically Interesting Molecule Reference Dictionary (BIRD). ![]()
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