Journal: Microbiology Spectrum

Article Title: Nanobody engineering for SARS-CoV-2 neutralization and detection

doi: 10.1128/spectrum.04199-22

Figure Lengend Snippet: Relative binding strengths of trimeric nanobodies to RBD and Spike S1 domain variants on an antigen microarray. ( A ) Three multimodular nanobody constructs were tested for binding to RBD variants with amino acid changes K417N, E484K, or N501Y, and to spike the S1 domain with four amino acid changes (K417N, E484K, N501Y, and D614G). Fluorescence signals of Dylight 633-labeled multimodular nanobodies Tri-Ty1, Tri-TMH, and Tri-TMV bound to the different RBD and S1 variants are shown normalized relative to the signal from binding to wild-type RBD or S1 for each nanobody, respectively. Error bars represent the standard deviation of two replicate measurements. ( B ) Location of the amino acid changes within the SARS-CoV-2 RBD. Amino acid change N501Y is found in the Alpha and Beta variants ( , ), and the Beta variant displays the additional changes K417N and E484K . Delta variant carries none of the three tested RBD amino acid changes, while Omicron displays N501Y, K417N, and an alternative change at residue 484, E484A.

Article Snippet: Wild-type and variant SARS-CoV-2 RBD and spike S1 domains were biotinylated and arrayed as duplicate spots (0.1 ng per spot) in the wells of streptavidin-coated microtitration plates using a piezoelectric non-contact microarray dispenser (Nano-Plotter, GeSiM, Germany).

Techniques: Binding Assay, Microarray, Construct, Fluorescence, Labeling, Standard Deviation, Variant Assay, Residue