Table 1.
Summary of kinetic rate constants (kon, koff), width of energy barriers (xB), and affinities (KD) of SARS-CoV-2 Spike or RBD of Wuhan reference strain, defined RBD mutants, and variants of concern determined using single molecule force spectroscopy
| Wuhan reference strain spike | Spike mutant N234Q | Delta variant spike | Omicron variant spike | Wuhan reference strain RBD | RBD mutant N501Y | RBD mutant E484K | Delta variant RBD | Omicron variant RBD | |
|---|---|---|---|---|---|---|---|---|---|
| kon (M−1 s−1) | 8.3 × 104±0.1 | 1.1 × 104±0.2 | 8.9 × 104±0.1 | 7.4 × 104±0.1 | 1.0 × 105±0.1 | 7.6 × 104±0.1 | 4.7 × 104±0.1 | 6.6 × 104±0.1 | 7.1 × 104±0.2 |
| xB (nm) | 1.7 ± 0.25 | 1.6 ± 0.43 | 1.9 ± 0.13 | 2.0 ± 0.21 | 1.7 ± 0.25 | 1.9 ± 0.26 | 2.0 ± 0.24 | 1.9 ± 0.26 | 2.0 ± 0.10 |
| koff (s−1) | 5.2 × 10−4±0.4 | 4.0 × 10−4±0.6 | 4.4 × 10−5±0.3 | 4.1 × 10−6±0.5 | 3.2 × 10−4±0.5 | 4.8 × 10−5±0.5 | 5.9 × 10−5±0.4 | 6.4 × 10−5±0.5 | 4.2 × 10−6±0.2 |
| KD (M) | 6.2 × 10−9±0.5 | 3.6 × 10−8±0.7 | 5.0 × 10−10±0.3 | 5.5 × 10−11±0.2 | 3.2 × 10−9±0.5 | 6.3 × 10−10±0.5 | 1.3 × 10−9±0.5 | 9.7 × 10−10±0.5 | 6.8 × 10−11±0.2 |