Discovery of selective and potent inhibitors of gram-positive bacterial thymidylate kinase (TMK).
Martínez-Botella G, Breen JN, Duffy JE, Dumas J, Geng B, Gowers IK, Green OM, Guler S, Hentemann MF, Hernandez-Juan FA, Joseph-McCarthy D, Kawatkar S, Larsen NA, Lazari O, Loch JT, Macritchie JA, McKenzie AR, Newman JV, Olivier NB, Otterson LG, Owens AP, Read J, Sheppard DW, Keating TA.
Thymidylate kinase (TMK) is an essential enzyme in bacterial DNA synthesis. The deoxythymidine monophosphate (dTMP) substrate binding pocket was targeted in a rational-design, structure-supported effort, yielding a unique series of antibacterial agents showing a novel, induced-fit binding mode. Lead optimization, aided by X-ray crystallography, led to picomolar inhibitors of both Streptococcus pneumoniae and Staphylococcus aureus TMK. MICs < 1 μg/mL were achieved against methicillin-resistant S. aureus (MRSA), S. pneumoniae, and vancomycin-resistant Enterococcus (VRE). Log D adjustments yielded single diastereomers 14 (TK-666) and 46, showing a broad antibacterial spectrum against Gram-positive bacteria and excellent selectivity against the human thymidylate kinase ortholog.