Table 1. Summary of Primary Screening Performed at Three Different Sites with Four Libraries.
| library | DSI-poised | extended DSI-poised | bionet | Maybridge |
|---|---|---|---|---|
| compound quantity | 768 | 896 | 428 | 800 |
| group | Schwalbe et al. | Orts et al. | Karlsson et al. | Karlsson et al. |
| performed NMR experiments | 1D 1H | STD | 19F T2 | T2-CPMG |
| STD | T2-CPMG | STD | ||
| waterLOGSY | T1rho | |||
| T2-CPMG | STD | |||
| NMR spectrometer | 600 MHz, cryoprobe | 600 MHz, cryoprobe | 600 and 700 MHz, cryoprobe (sites 1 and 2) | 600 MHz, cryoprobe |
| sample condition | 10 μM GHMnsp5, 200 μM of each ligand in 25 mM NaPi (pH 7.5), 150 mM NaCl, 5% d6-DMSO. | 11.5 μM GSnsp5GPH6, 320 μM of each ligand in 10 mM NaPi (pH 7.6), 50 mM NaCl in D2O, 0.04% NaN3, 3.85% d6-DMSO. | 10 μM wt Mpro, 100 μM of each ligand in 10 mM NaPi (pH 7.4), 130 mM NaCl, 2.4 mM KCl, 10% D2O, 8% d6-DMSO. | 10 μM wt Mpro, 100 μM of each ligand in 10 mM NaPi (pH 7.4), 130 mM NaCl, 2.4 mM KCl, 10% D2O, 1% d6-DMSO. |
| ligand mixture | 12 ligands per mixture, 64 mixtures in total | max. six ligands per mixture | 9–11 ligands per mixture | 10 ligands per mixture |
| hit definition | satisfaction of ≥2 criteria | STD signal | binding response in ≥5 experiments: | |
| CSP | S/N > 10 | T2 (site 1) | ||
| line broadening | STD (site 1) | |||
| sign change in the waterLOGSY | 19F T2 (site 1) | Binding response in both experiments: | ||
| STD signal | T1rho (site 2) | T2 | ||
| Signal intensity decrease in T2-CPMG | STD (site 2) | STD | ||
| 19F T2 (site 2) | ||||
| additional experiments | X-ray | SPR | SPR | |
| SPR | ||||
| TSA |