Table 1.

Details of energies and inhibition constant values between top-ranked flavonoids, control compounds, and SauPBP2a achieved from the AutoDock tool.

(A) Docking results with the active site of the enzyme
Ligand name	Final intermolecular energy (kcal/mol)	Final total internal energy (kcal/mol)	Torsional free energy (kcal/mol)	Unbound system's energy (kcal/mol)	Estimated free binding energy (kcal/mol)	Ki
Kaempferol 3-rutinoside-7-sophoroside	−12.8	−3.4	2.7	−1.4	−12.1	1.4 nM
Rutin	−8.0	−10.2	4.8	−2.2	−11.1	6.8 nM
Amentoflavone	−9.7	−4.4	2.7	−1.2	−10.2	31.6 nM
Quercetin	−9.9	−6.6	4.5	−1.9	−10.1	36.6 nM
PNM (ctrl ‒)	−7.9	−1.1	1.8	−0.9	−6.4	22.1 uM
Methicillin (ctrl ‒)	−6.8	−1.8	1.8	−1.3	−5.5	91.2 uM
Oxadiazole (ctrl +)	−9.2	−0.9	1.5	−0.7	−7.9	1.7 uM
Ceftobiprole (ctrl +)	−10.6	−2.1	2.7	−1.2	−8.8	362.2 nM
(B) Docking results with the allosteric site of the enzyme
Ligand name	Final intermolecular energy (kcal/mol)	Final total internal energy (kcal/mol)	Torsional free energy (kcal/mol)	Unbound system's energy (kcal/mol)	Estimated free binding energy (kcal/mol)	Ki
Kaempferol 3-rutinoside-7-sophoroside	−7.3	−17.8	7.5	−3.3	−14.4	30.30 pM
Rutin	−7.4	−9.8	5.1	−2.4	−9.7	79.98 nM

SauPBP2a, Staphylococcus aureus penicillin-binding protein 2a; PNM, penicillin G; Ki, inhibition constant; nM, nanomolar; pM, picomolar.