A hydrophobic patch in the VBM of CEACAM1 functions as a virus-binding hot spot. Mutations in this region significantly decreased the binding bof MHV S1-NTD. Taken together, these results suggests that MHV S1-NTD and host galectins share the same evolutionary origin. They also indicate that although MHV S1-NTDs may nind sugar receptors and function as viral lectins.