Table 6.
Summary of virtual ligand screening, thermal shift assay and binding parameters for the hits obtained on E. coli DHFR.
| Identity | Rank | Rank2D | Q# | Tm (° C) | ΔTm (° C) | KD (μM)c |
|---|---|---|---|---|---|---|
|
| ||||||
| Protein | NA | NA | 1.00 | 51.9 | NA | NA |
| NSC339578* | 6 | 777 | 0.35 | 69.5 | 17.6 | 02.4 ± 0.6 |
| NSC71669 | 75 | 863 | 0.32 | 66.9 | 15.0 | 05.2 ± 1.3 |
| NSC305782 | 46 | 1485 | 0.20 | 66.3 | 14.4 | 06.2 ± 1.2 |
| NSC740* | 18 | 674 | 0.34 | 66.3 | 14.4 | 06.2 ± 1.6 |
| NSC133071 | 25 | 119 | 0.41 | 66.2 | 14.3 | 06.4 ± 1.5 |
| NSC7364* | 5 | 1303 | 0.43 | 64.4 | 12.5 | 10.8 ± 2.1 |
| NSC309401* | 7 | 129 | 0.31 | 63.6 | 11.7 | 13.7 ± 1.8 |
| CHEMBL597262 | 1 | 41 | 0.42 | 62.6 | 10.7 | 18.4 ± 2.7 |
| NSC168184 | 3 | 109 | 0.23 | 62.4 | 10.5 | 19.5 ± 3.5 |
| CHEMBL333873 | 2 | 90 | 0.31 | 61.5 | 9.6 | 25.6 ± 3.8 |
| NSC117268 | 60 | 254 | 0.43 | 60.4 | 8.5 | 35.7 ± 6.3 |
| NSC11150 | 77 | 69 | 0.50 | 58.4 | 6.5 | 65.6 ± 11.1 |
| NSC104129 | 10 | 80 | 0.32 | 57.3 | 5.4 | 91.9 ± 14.0 |
| NSC89759 | 51 | 66 | 0.30 | 55.1 | 3.2 | 182.1± 21.6 |
*
Indicates reported inhibitors of DHFR independently picked up by PoLi and validated experimentally. Rank2D is the rank of identified inhibitors using 2D fingerprint similarity (TC) using same set of templates as used by PoLi,
#
quality score (Q) is the ratio of the melting-associated increase in fluorescence (ΔFmelt) and total range in fluorescence (ΔFtotal). A Q value of 1 represents a high-quality curve, while a value of 0 shows an absence of melting as described earlier49. KDC is the dissociation constant computed from the magnitude thermal shifts obtained relative to the protein alone.