A novel mycolic acid cyclopropane synthetase is required for cording, persistence, and virulence of Mycobacterium tuberculosis.
Colonial morphology of pathogenic bacteria is often associated with virulence. For M. tuberculosis, the causative agent of tuberculosis (TB), virulence is correlated with the formation of serpentine cords, a morphology that was first noted by Koch. We identified a mycobacterial gene, pcaA, that we show is required for cording and mycolic acid cyclopropane ring synthesis in the cell wall of both BCG and M. tuberculosis. Furthermore, we show that mutants of pcaA fail to persist within and kill infected mice despite normal initial replication. These results indicate that a novel member of a family of cyclopropane synthetases is necessary for lethal chronic persistent M. tuberculosis infection and define a role for cyclopropanated lipids in bacterial pathogenesis.
Glickman
M S
MS
Division of Infectious Diseases, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York 10461, USA.
Cox
J S
JS
Jacobs
W R
WR
D000818:Animals; D002908:Chronic Disease / Q000401:mortality; D008780:Methyltransferases / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D009154:Mutation; D009169:Mycobacterium tuberculosis / Q000166:cytology* / Q000201:enzymology / Q000472:pathogenicity*; D009171:Mycolic Acids / Q000378:metabolism*; D010641:Phenotype; D014376:Tuberculosis / Q000401:mortality
D009171:Mycolic Acids; D008780:Methyltransferases; C019964:cyclopropane synthetase