Sequence alignment of the surface loops of the P domains forming the HBGA-binding interfaces.

<p>Sequences of the six surface loops forming on the HBGA-binding interfaces representing the two genotypes of the GII.21 and GII.13, as well as GII.17, the genotype genetically close-relating to the GII.13/21 lineage, and GII.4 as a representative of the GII noroviruses (NoVs) with the conventional GII HBGA binding interfaces are aligned. The six surface loops that contribute to the formation of the two types of GII HBGA binding interfaces are labeled. The conserved residues forming the binding interface of OIF virus are shown in red fonts and labeled by red asterisks, while those forming the conventional GII binding interface are shown in blue fonts and labeled by blue asterisks. The GenBank accession numbers of P domain sequences are: AY675554 (OIF), AFC89665.1 (Sal), AY113106 (Fay), JN899242 (173), AY502009 (CSE), AY038600 (387).