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 (Tm) ThyX in complex with a nonsubstrate
analog inhibitor. Given the active site similarities between Mycobacterium tuberculosis ThyX (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.