1IQB

Crystal Structure of Urtica dioica Agglutinin Isolectin I

Summary for 1IQB

• Entry DOI: 10.2210/pdb1iqb/pdb
• Descriptor: AGGLUTININ ISOLECTIN I, ZINC ION (3 entities in total)
• Functional Keywords: two homologous hevein-like domains, zinc complex, homo-dimer, sugar binding protein
• Biological source: Urtica dioica (great nettle)
• Total number of polymer chains: 2
• Total formula weight: 18947.59

Authors

Harata, K.,Schubert, W.D.,Muraki, M. (deposition date: 2001-07-15, release date: 2001-11-07, Last modification date: 2024-11-13)

Primary citation

Harata, K.,Schubert, W.D.,Muraki, M.
Structure of Urtica dioica agglutinin isolectin I: dimer formation mediated by two zinc ions bound at the sugar-binding site.
Acta Crystallogr.,Sect.D, 57:1513-1517, 2001

PubMed Abstract: Ultica dioica agglutinin, a plant lectin from the stinging nettle, consists of a total of seven individual isolectins. One of these structures, isolectin I, was determined at 1.9 A resolution by the X-ray method. The crystals belong to the space group P2(1) and the asymmetric unit contains two molecules related by local twofold symmetry. The molecule consists of two hevein-like chitin-binding domains lacking distinct secondary structure, but four disulfide bonds in each domain maintain the tertiary structure. The backbone structure of the two independent molecules is essentially identical and this is similarly true of the sugar-binding sites. In the crystal, the C-terminal domains bind Zn(2+) ions at the sugar-binding site. Owing to their location near a pseudo-twofold axis, the two zinc ions link the two independent molecules in a tail-to-tail arrangement: thus, His47 of molecule 1 and His67 of molecule 2 coordinate the first zinc ion, while the second zinc ion links Asp75 of molecule 1 and His47 of molecule 2.

PubMed: 11679714
DOI: 10.1107/S090744490101232X

Experimental method

X-RAY DIFFRACTION (1.9 Å)