Skip to main content
. 2022 May 24;17(5):e0268767. doi: 10.1371/journal.pone.0268767

Fig 3. Characterization of purified biotinylated SARS-CoV-2 variant S2P probes confirms their homogeneity and antibody-binding specificity.

Fig 3

(A) Size exclusion chromatography of the purified biotinylated SARS-CoV-2 S2P probes, including original WA-1 S2P, single mutated D614G S2P, and 15 other variant S2P, in PBS buffer. (B) SDS-PAGE of SARS-CoV-2 S2P variant probes with and without reducing agent. Molecular weight marker (MWM), the WA-1 S2P probe, and the D614G S2P probe, were run alongside the variant S2P probes. (C) Biotinylation and receptor recognition of the SARS-CoV-2 variant S2P probes. The level of biotinylation was evaluated by capture of the S2P probes at 10 μg/ml onto the streptavidin biosensors using Octet. Receptor binding was assessed with 500 nM of dimeric ACE2. Error bars represent standard deviation of triplicate measurements. (D) Antigenicity assessment of the SARS-CoV-2 variant S2P probes. Responses to RBD-directed, NTD-directed, and S2 subunit-directed antibodies were shown in cyan, orange, and rose, respectively. Bar scale between 0 and 1. Negative values not depicted.