1WGT

X-RAY STRUCTURE OF WHEAT GERM AGGLUTININ ISOLECTIN 3

Summary for 1WGT

• Entry DOI: 10.2210/pdb1wgt/pdb
• Descriptor: WHEAT GERM LECTIN (2 entities in total)
• Functional Keywords: lectin (agglutinin)
• Biological source: Triticum aestivum (bread wheat)
• Total number of polymer chains: 2
• Total formula weight: 37505.86

Authors

Harata, K.,Nagahora, H.,Jigami, Y. (deposition date: 1995-04-17, release date: 1995-07-10, Last modification date: 2024-10-23)

Primary citation

Harata, K.,Nagahora, H.,Jigami, Y.
X-ray structure of wheat germ agglutinin isolectin 3.
Acta Crystallogr.,Sect.D, 51:1013-1019, 1995

PubMed Abstract: Wheat germ agglutinin isolectin 3 (WGA3) was crystallized from 10 mM acetate buffer at pH 4.9 containing 6 mM CaCl(2) and 4%(v/v) ethanol. The crystal belongs to monoclinic space group P2(1) with unit-cell dimensions a = 44.86, b = 91.02, c = 44.86 A, and beta = 110.22 degrees. The asymmetric unit contains two molecules (V(m) = 2.51 A(3) Da(-1)). The crystal structure was solved by the molecular-replacement method and was refined by the simulated-annealing method. The conventional R value was 0.191 for 19713 reflections [|F(o)| > 3sigma(F)] in the resolution range 8-1.9 A. The r.m.s. deviations from the ideal bond distances and angles were 0.014 A, and 3.0 degrees, respectively, and the estimated coordinate error was 0.2-0.25 A. The two molecules in the asymmetric unit are related by the pseudo twofold symmetry and form a dimer structure. The backbone structures of the two subunits are nearly identical with the r.m.s. difference of 0.36 A for the superposition of equivalent C(alpha) atoms. The dimer structure is very similar to those of isolectins 1 and 2 with the r.m.s. difference of 0.35-0.39 A for the C(alpha) superposition. Since amino-acid residues which differ from those of isolectin 1 or 2 are not involved in the contact between the two subunits, the subunit-subunit interaction is not significantly affected by the replacement of these residues. As a result, the geometry of the sugar-binding sites which are located at the interface between the two subunit molecules is basically conserved among three isolectins.

PubMed: 15299769
DOI: 10.1107/S0907444995004070

Experimental method

X-RAY DIFFRACTION (1.9 Å)