FIG. 1.

Receptor specificity of the HK213 virus. (A) The solid-phase binding assay with competing glycopolymers was performed as described in a previous report (14). The binding of HK213 virus to fetuin was not inhibited by a polymer possessing either an α(2,3)- or an α(2,6)-linked sialic acid, unlike the human and avian viruses used as controls for α2,3 or α2,6 binder, respectively. (B) The direct binding activity of viruses to gangliosides was determined by a previously published method (28). The HK213 virus has the ability to bind to both the α(2,3)- and α(2,6)-linked sialic acids.