FIG. 3.

Detection of carbohydrates by periodate oxidation. Parental F protein (lane a) and mutants N500Q (lane b), N27/500Q (lane c), and N27/70/500Q (lane d) were expressed in BSR-T7/5 cells, immunoprecipitated with a monoclonal antibody, and separated by SDS-polyacrylamide gel electrophoresis. Cells transfected with a nonrecombinant vector plasmid (lane e) were used as a control. (Upper panel) The F proteins were transferred to a polyvinylidene difluoride membrane and treated with sodium metaperiodate. The oxidized carbohydrates were conjugated with biotin-hydrazide and detected with streptavidin-peroxidase. (Lower panel) The F proteins were transferred to a nitrocellulose membrane and detected by sequential incubation with a monoclonal antibody (Mab) directed against the HRSV F protein, a biotinylated anti-mouse immunoglobulin serum, and streptavidin-peroxidase.