Archives of Microbiology

, Volume 193, Issue 3, pp 227–234 | Cite as

Pseudomonas aeruginosa aerobic fatty acid desaturase DesB is important for virulence factor production

Short Communication


Unsaturated fatty acids (UFAs) play a pivotal role in maintaining a functional cellular membrane in response to changes in environmental factors. Unlike in other gram-negative bacteria, in Pseudomonas aeruginosa, UFA synthesis is governed by 2 pathways: (1) the anaerobic FabAB-mediated pathway and (2) the aerobic inducible DesA/DesB desaturase pathway. Although fatty acids are functional constituents of several known virulence factors, the roles of Pseudomonas aeruginosa fatty acid synthesis enzymes in virulence factor production and pathogenesis have not yet been examined. Previous studies have shown that the mycobacterial DesA1 and DesA3 proteins are required for full virulence. Therefore, we assessed the effect, if any, of mutations affecting the various UFA synthesis enzymes on virulence factor production. Testing of individual mutations or combinations of mutations revealed that desB mutants were severely deficient in the production of proteolytic enzymes, pyocyanin, and rhamnolipid. In addition, the desB mutants showed impaired swarming and twitching motilities and reduced virulence in the Caenorhabditis elegans infection model. Taken together, these results demonstrate that DesB is not only a fatty acid desaturase but also a factor required for full virulence in Pseudomonas aeruginosa. DesB may thus constitute a novel drug target.


Pseudomonas aeruginosa DesB Desaturase Virulence factor 



This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2010-0004068).


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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  1. 1.Department of Microbiology, Immunology, and Pathology, IDRC at Foothills CampusColorado State UniversityFort CollinsUSA
  2. 2.Department of Oral Microbiology, College of DentistryWonkwang UniversityIksan, ChonbukSouth Korea

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