Fig. 3

Expression and identification of nanobodies against SRMV. (A) Prokaryotic expression of nanobodies against SRMV (M standard protein marker, 1–2 supernatant and precipitation of negative bacteria respectively, 3–4 supernatant and precipitation of NbSRMV-1-1 expression bacteria respectively, 5–6 supernatant and precipitation of NbSRMV-2-10 expression bacteria respectively, 7–8 supernatant and precipitation of NbSRMV-1-11 expression bacteria respectively, 9–10 supernatant and precipitation of NbSRMV-1-21 expression bacteria respectively, 11–12 supernatant and precipitation of NbSRMV-2-34 expression bacteria respectively). (B) Purification of nanobodies against SRMV (M standard protein marker, 1 purified NbSRMV-1-1, 2 purified NbSRMV-2-10, 3 purified NbSRMV-1-21). (C) Western blotting analysis of nanobodies against SRMV (M standard protein marker, 1 NbSRMV-1-1, 2 NbSRMV-2-10, 3 NbSRMV-1-21, Nc BSA negative control). (D) Specificity analysis of nanobodies against inactivated SRMV. (E) Binding affinity analysis of the nanobodies against inactivated SRMV using ELISA