3AST: Crystal Structure Of P Domain Q389n Mutant From Norovirus Funabashi258 Stain In The Complex With Lewis-b

Noroviruses (NoVs) bind to histo-blood group antigens, namely, ABH antigens and Lewis antigens. We previously showed the NoVs GI/2, GI/3, GI/4, and GI/8 were able to strongly bind to Lewis a (Le(a)) antigen, which is expressed by individuals who are nonsecretors. In this study, to investigate how Lewis antigens interact with GI NoV virion protein 1 (VP1), we determined the crystal structures of the P domain of the VP1 protein from the Funabashi 258 (FUV258) strain (GI/2) in complexes with Le(a), Le(b), H type 1, or A type 1 antigens. The structures were compared with those of the NV/68 strain (GI/1), which does not bind to the Le(a) antigen. The four loop structures, loop P, loop S, loop A, and loop B, continuously deviated by more than 2 A in length between the Calpha atoms of the corresponding residues of the FUV258 and NV/68 P domains. The most pronounced differences between the two VP1 proteins were observed in the structures of loop P. In the FUV258 P domain, loop P protruded toward the next protomer, forming a Le(a) antigen-binding site. The Gln389 residue make a significant contribution to the binding of the Le(a) antigen through the stabilization of loop P as well as through direct interactions with the alpha4-fucosyl residue (alpha4Fuc) of the Le(a) antigen. Mutation of the Gln389 residue dramatically affected the degree of binding of the Lewis antigens. Collectively, these results suggest that loop P and the amino acid residue at position 389 affect Lewis antigen binding.
PDB ID: 3ASTDownload
MMDB ID: 96635
PDB Deposition Date: 2010/12/17
Updated in MMDB: 2013/11
Experimental Method:
x-ray diffraction
Resolution: 1.4  Å
Source Organism:
Similar Structures:
Biological Unit for 3AST: dimeric; determined by author and by software (PISA)
Molecular Components in 3AST
Label Count Molecule
Proteins (2 molecules)
Capsid Protein
Molecule annotation
Chemicals (12 molecules)
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Citing MMDB