Database accession: MF2110027
Name: Mannose-binding lectin (Hyacinthoides hispanica)
PDB ID: 1b2p
Experimental method: X-ray (1.70 Å)
Assembly: homodimer
Source organism: Hyacinthoides hispanica
Primer publication of the structure:
Wood SD, Wright LM, Reynolds CD, Rizkallah PJ, Allen AK, Peumans WJ, Van Damme EJ
Structure of the native (unligated) mannose-specific bulb lectin from Scilla campanulata (bluebell) at 1.7 A resolution.
(1999) Acta Crystallogr. D Biol. Crystallogr. 55: 1264-72
PMID: 10393293
Abstract:
The X-ray crystal structure of native Scilla campanulata agglutinin, a mannose-specific lectin from bluebell bulbs and a member of the Liliaceae family, has been determined by molecular replacement and refined to an R value of 0.186 at 1.7 A resolution. The lectin crystallizes in space group P21212 with unit-cell parameters a = 70. 42, b = 92.95, c = 46.64 A. The unit cell contains eight protein molecules of Mr = 13143 Da (119 amino-acid residues). The asymmetric unit comprises two chemically identical molecules, A and B, related by a non-crystallographic twofold axis perpendicular to c. This dimer further associates by crystallographic twofold symmetry to form a tetramer. The fold of the polypeptide backbone closely resembles that found in the lectins from Galanthus nivalis (snowdrop) and Hippeastrum (amaryllis) and contains a threefold symmetric beta-prism made up of three antiparallel four-stranded beta-sheets. Each of the four-stranded beta-sheets (I, II and III) possesses a potential saccharide-binding site containing conserved residues; however, site II has two mutations relative to sites I and III which may prevent ligation at this site. Our study provides the first accurate and detailed description of a native (unligated) structure from this superfamily of mannose-specific bulb lectins and will allow comparisons with a number of lectin-saccharide complexes which have already been determined or are currently under investigation.
Annotations from the GeneOntology database. Only terms that fit at least two of the interacting proteins are shown.Molecular function: not assigned
Biological process: not assigned
Cellular component: not assigned
Structural annotations of the participating protein chains.Entry contents: 2 distinct polypeptide molecules
Chains: A, B
Notes: No modifications of the original PDB file. Chain identifiers are identical with the PDB's identifiers.
Number of unique protein segments: 1
Name: Lectin SCAman (Fragment)
Source organism: Hyacinthoides hispanica
Length: 119 residues
Sequence:Sequence according to PDB SEQRESNNIIFSKQPDDNHPQILHATESLEILFGTHVYRFIMQTDCNLVLYDNNNPIWATNTGGLGNGCRAVLQPDGVLVVITNENVTVWQSPVAGKAGHYVLVLQPDRNVVIYGDALWATQTVR
UniProtKB AC: Q9ZP49 (positions: 22-140) Coverage: 76.8%
UniRef90 AC: UniRef90_Q9ZP49 (positions: 22-140)
Name: Lectin SCAman (Fragment)
Source organism: Hyacinthoides hispanica
Length: 119 residues
Sequence:Sequence according to PDB SEQRESNNIIFSKQPDDNHPQILHATESLEILFGTHVYRFIMQTDCNLVLYDNNNPIWATNTGGLGNGCRAVLQPDGVLVVITNENVTVWQSPVAGKAGHYVLVLQPDRNVVIYGDALWATQTVR
UniProtKB AC: Q9ZP49 (positions: 22-140) Coverage: 76.8%
UniRef90 AC: UniRef90_Q9ZP49 (positions: 22-140)
Evidence demonstrating that the participating proteins are unstructured prior to the interaction and their folding is coupled to binding. Complex evidence:
A closely homologous lectin of the same type sharing a high degree of sequence and structural similarity has been shown to follow a two-state folding process (PMID: 11401577).
Structures from the PDB that contain the same number of proteins, and the proteins from the two structures show a sufficient degree of pairwise similarity, i.e. they belong to the same UniRef90 cluster (the full proteins exhibit at least 90% sequence identity) and convey roughly the same region to their respective interactions (the two regions from the two proteins share a minimum of 70% overlap). No related structure was found in the Protein Data Bank.
