Summary of the mutagenesis study of the three sites of the HBGA-binding interface of MOH (GII-5) and VA207 (GII-9) predicted by sequence alignment with that of Norwalk virus (GI) and VA387 (GII).

1The number of “+” indicated the relative binding affinity of the wild type (WT) and mutant P particles at 16.7 ng/µl to HBGAs: “+++” indicates an OD450 >2.0; “++” between 1.0 and 2.0; “+” between 0.3 and 1.0; while “−” indicates an OD450 <0.3, suggesting a complete loss of binding. Saliva samples of type A, B, AB, and O were from secretors containing A, B, A/B and H antigen, respectively.