Virtual Screening and X-ray Crystallography Identify Non-Substrate Analog Inhibitors of Flavin-Dependent Thymidylate Synthase

Thymidylate synthase-X (ThyX) represents an attractive target for tuberculosis drug discovery. Herein, we selected 16 compounds through a virtual screening approach. We solved the first X-ray crystal structure of Thermatoga maritima ThyX in complex with a non-substrate analog inhibitor. Given the active site similarities between Mtb-ThyX and Tm-ThyX, our crystal structure paves the way for a structure-based design of novel antimycobacterial compounds. The 1H-imidazo[4,5-d]pyridazine was identified as scaffold for the development of Mtb-ThyX inhibitors.