title: Antituberculosis thiophenes define a requirement for Pks13 in mycolic acid biosynthesis.
abstract: We report a new class of thiophene (TP) compounds that kill Mycobacterium tuberculosis by the previously uncharacterized mechanism of Pks13 inhibition. An F79S mutation near the catalytic Ser55 site in Pks13 conferred TP resistance in M. tuberculosis. Overexpression of wild-type Pks13 resulted in TP resistance, and overexpression of the Pks13(F79S) mutant conferred high resistance. In vitro, TP inhibited fatty acyl-AMP loading onto Pks13. TP inhibited mycolic acid biosynthesis in wild-type M. tuberculosis, but it did so to a much lesser extent in TP-resistant M. tuberculosis. TP treatment was bactericidal and equivalent to treatment with the first-line drug isoniazid, but it was less likely to permit emergent resistance. Combined isoniazid and TP treatment resulted in sterilizing activity. Computational docking identified a possible TP-binding groove within the Pks13 acyl carrier protein domain. This study confirms that M. tuberculosis Pks13 is required for mycolic acid biosynthesis, validates it as a druggable target and demonstrates the therapeutic potential of simultaneously inhibiting multiple targets in the same biosynthetic pathway.
authors.affiliation: Division of Infectious Disease, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, New Jersey, USA.
authors.forename: Regina
authors.initials: R
authors.lastname: Wilson
authors.forename: Pradeep
authors.initials: P
authors.lastname: Kumar
authors.forename: Vijay
authors.initials: V
authors.lastname: Parashar
authors.forename: Catherine
authors.initials: C
authors.lastname: Vilchèze
authors.forename: Romain
authors.initials: R
authors.lastname: Veyron-Churlet
authors.forename: Joel S
authors.initials: JS
authors.lastname: Freundlich
authors.forename: S Whitney
authors.initials: SW
authors.lastname: Barnes
authors.forename: John R
authors.initials: JR
authors.lastname: Walker
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Szymonifka
authors.forename: Emily
authors.initials: E
authors.lastname: Marchiano
authors.forename: Shubhada
authors.initials: S
authors.lastname: Shenai
authors.forename: Roberto
authors.initials: R
authors.lastname: Colangeli
authors.forename: William R
authors.initials: WR
authors.lastname: Jacobs
authors.forename: Matthew B
authors.initials: MB
authors.lastname: Neiditch
authors.forename: Laurent
authors.initials: L
authors.lastname: Kremer
authors.forename: David
authors.initials: D
authors.lastname: Alland
mesh_terms: D000995:Antitubercular Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism*; D055162:Biocatalysis; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D009154:Mutation; D009169:Mycobacterium tuberculosis / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D009171:Mycolic Acids / Q000378:metabolism*; D048630:Polyketide Synthases / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism*; D013329:Structure-Activity Relationship; D013876:Thiophenes / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000995:Antitubercular Agents; D001426:Bacterial Proteins; D009171:Mycolic Acids; D013876:Thiophenes; C576758:polyketide synthase Pks13, Mycobacterium tuberculosis; D048630:Polyketide Synthases