AbstractShikimate kinase (SK) is the fifth enzyme in the shikimate pathway and catalyzes the phosphate transfer from ATP to
shikimate in generating shikimate 3-phosphate and ADP. SK has been developed as a promising target for the discovery of
antibacterial agents. In this report, two small molecular inhibitors (compound 1, 3-methoxy-4-{[2-({2-methoxy-4-[(4-oxo-2-thioxo-
1,3-thiazolidin-5-ylidene)methyl]phenoxy}methyl)benzyl]oxy}benzaldehyde; compound 2, 5-bromo-2-(5-{[1-(3,4-dichlorophenyl)-
3,5-dioxo-4-pyrazolidinylidene]methyl}-2-furyl)benzoic acid) against Helicobacter pylori SK (HpSK) were successfully
identified with IC50 values of 5.5 1.2 and 6.4 0.4 lM, respectively. The inhibition kinetics shows that compound 1 is a noncompetitive
inhibitor with respect to both shikimate and MgATP, and compound 2 is a competitive inhibitor toward shikimate and
noncompetitive inhibitor with respect to MgATP. The surface plasmon resonance (SPR) technology based analysis reveals that
the equilibrium dissociation constants (KDs) of compounds 1 and 2 with HpSK enzyme are 4.39 and 3.74 lM, respectively. The
molecular modeling and docking of two inhibitors with HpSK reveals that the active site of HpSK is rather roomy and deep, forming
an L-shape channel on the surface of the protein, and compound 1 prefers the corner area of L-shape channel, while compound 2
binds the short arm of the channel of SK in the binding interactions. It is expected that our current work might supply useful
information for the development of novel SK inhibitors.