Inhibition of bacterial disulfide bond formation by the anticoagulant warfarin.
Blood coagulation in humans requires the activity of vitamin K epoxide reductase (VKOR), the target of the anticoagulant warfarin (Coumadin). Bacterial homologs of VKOR were recently found to participate in a pathway leading to disulfide bond formation in secreted proteins of many bacteria. Here we show that the VKOR homolog from the bacterium Mycobacterium tuberculosis, the causative agent of human tuberculosis, is inhibited by warfarin and that warfarin-resistant mutations of mycobacterial VKOR appear in similar locations to mutations found in human patients who require higher doses of warfarin. Deletion of VKOR results in a severe growth defect in mycobacteria, and the growth of M. tuberculosis is inhibited by warfarin. The bacterial VKOR homolog may represent a target for antibiotics and a model for genetic studies of human VKOR. We present a simple assay in Escherichia coli, based on a disulfide-sensitive beta-galactosidase, which can be used to screen for stronger inhibitors of the M. tuberculosis VKOR homolog.
Dutton
Rachel J
RJ
Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, MA 02115, USA.
Wayman
April
A
Wei
Jun-Rong
JR
Rubin
Eric J
EJ
Beckwith
Jon
J
Boyd
Dana
D
D000595:Amino Acid Sequence; D000818:Animals; D000925:Anticoagulants / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D004220:Disulfides / Q000737:chemistry*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D006801:Humans; D006899:Mixed Function Oxygenases / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D015394:Molecular Structure; D009154:Mutation; D009169:Mycobacterium tuberculosis / Q000187:drug effects* / Q000201:enzymology; D010084:Oxidation-Reduction; D016415:Sequence Alignment; D064417:Vitamin K Epoxide Reductases; D014859:Warfarin / Q000494:pharmacology*
D000925:Anticoagulants; D001426:Bacterial Proteins; D004220:Disulfides; D014859:Warfarin; D006899:Mixed Function Oxygenases; D064417:Vitamin K Epoxide Reductases