title: Identification of KasA as the cellular target of an anti-tubercular scaffold.
abstract: Phenotypic screens for bactericidal compounds are starting to yield promising hits against tuberculosis. In this regard, whole-genome sequencing of spontaneous resistant mutants generated against an indazole sulfonamide (GSK3011724A) identifies several specific single-nucleotide polymorphisms in the essential Mycobacterium tuberculosis β-ketoacyl synthase (kas) A gene. Here, this genomic-based target assignment is confirmed by biochemical assays, chemical proteomics and structural resolution of a KasA-GSK3011724A complex by X-ray crystallography. Finally, M. tuberculosis GSK3011724A-resistant mutants increase the in vitro minimum inhibitory concentration and the in vivo 99% effective dose in mice, establishing in vitro and in vivo target engagement. Surprisingly, the lack of target engagement of the related β-ketoacyl synthases (FabH and KasB) suggests a different mode of inhibition when compared with other Kas inhibitors of fatty acid biosynthesis in bacteria. These results clearly identify KasA as the biological target of GSK3011724A and validate this enzyme for further drug discovery efforts against tuberculosis.
authors: Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
authors: Katherine A
authors: KA
authors: Abrahams
authors: GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK.
authors: Chun-Wa
authors: CW
authors: Chung
authors: Cellzome-a GSK Company, Meyerhofstrasse 1, 69117 Heidelberg, Germany.
authors: Sonja
authors: S
authors: Ghidelli-Disse
authors: Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos, 28760 Madrid, Spain.
authors: Joaquín
authors: J
authors: Rullas
authors: Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos, 28760 Madrid, Spain.
authors: María José
authors: MJ
authors: Rebollo-López
authors: Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
authors: Sudagar S
authors: SS
authors: Gurcha
authors: Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
authors: Jonathan A G
authors: JA
authors: Cox
authors: Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos, 28760 Madrid, Spain.
authors: Alfonso
authors: A
authors: Mendoza
authors: Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos, 28760 Madrid, Spain.
authors: Elena
authors: E
authors: Jiménez-Navarro
authors: Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos, 28760 Madrid, Spain.
authors: María Santos
authors: MS
authors: Martínez-Martínez
authors: GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK.
authors: Margarete
authors: M
authors: Neu
authors: GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK.
authors: Anthony
authors: A
authors: Shillings
authors: GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK.
authors: Paul
authors: P
authors: Homes
authors: GlaxoSmithKline, Gunnels Wood Road, Stevenage SG1 2NY, UK.
authors: Argyrides
authors: 0000-0003-3141-9122
authors: A
authors: Argyrou
authors: Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos, 28760 Madrid, Spain.
authors: Ruth
authors: R
authors: Casanueva
authors: Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
authors: Nicholas J
authors: NJ
authors: Loman
authors: Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
authors: Patrick J
authors: PJ
authors: Moynihan
authors: Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos, 28760 Madrid, Spain.
authors: Joël
authors: J
authors: Lelièvre
authors: GlaxoSmithKline, 709 Swedeland Road, PO Box 1539, King of Prussia, Pennsylvania 19406-0939, USA.
authors: Carolyn
authors: C
authors: Selenski
authors: GlaxoSmithKline, 709 Swedeland Road, PO Box 1539, King of Prussia, Pennsylvania 19406-0939, USA.
authors: Matthew
authors: M
authors: Axtman
authors: Centre National de la Recherche Scientifique FRE 3689, Centre d'études d'agents Pathogènes et Biotechnologies pour la Santé, Université de Montpellier, 1919 route de Mende, 34293 Montpellier, France.|INSERM, CPBS, 34293 Montpellier, France.
authors: Laurent
authors: L
authors: Kremer
authors: Cellzome-a GSK Company, Meyerhofstrasse 1, 69117 Heidelberg, Germany.
authors: Marcus
authors: 0000-0002-8343-8977
authors: M
authors: Bantscheff
authors: Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos, 28760 Madrid, Spain.
authors: Iñigo
authors: I
authors: Angulo-Barturen
authors: Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos, 28760 Madrid, Spain.
authors: Mónica Cacho
authors: MC
authors: Izquierdo
authors: Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos, 28760 Madrid, Spain.
authors: Nicholas C
authors: NC
authors: Cammack
authors: Cellzome-a GSK Company, Meyerhofstrasse 1, 69117 Heidelberg, Germany.
authors: Gerard
authors: G
authors: Drewes
authors: Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos, 28760 Madrid, Spain.
authors: Lluis
authors: L
authors: Ballell
authors: Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos, 28760 Madrid, Spain.
authors: David
authors: D
authors: Barros
authors: Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
authors: Gurdyal S
authors: GS
authors: Besra
authors: Diseases of the Developing World, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos, 28760 Madrid, Spain.
authors: Robert H
authors: RH
authors: Bates
mesh_terms: D015099:3-Oxoacyl-(Acyl-Carrier-Protein) Synthase / Q000037:antagonists & inhibitors* / Q000235:genetics*; D000818:Animals; D000995:Antitubercular Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics*; D024881:Drug Resistance, Bacterial / Q000235:genetics; D005260:Female; D007191:Indazoles / Q000494:pharmacology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008826:Microbial Sensitivity Tests; D009169:Mycobacterium tuberculosis / Q000187:drug effects* / Q000235:genetics; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D013449:Sulfonamides / Q000494:pharmacology*; D014397:Tuberculosis, Pulmonary / Q000188:drug therapy* / Q000382:microbiology / Q000517:prevention & control
chemical_list: D000995:Antitubercular Agents; D001426:Bacterial Proteins; D007191:Indazoles; D013449:Sulfonamides; C444656:KasB protein, Mycobacterium tuberculosis; D015099:3-Oxoacyl-(Acyl-Carrier-Protein) Synthase; C530127:FabH protein, Mycobacterium tuberculosis