| Autor: |
Ernst S; Institute for Molecular Microbiology and Biotechnology, University of Münster, Corrensstr. 3, Münster 48149, Germany., Volkov AN; VIB Centre for Structural Biology, Vlaams Instituut voor Biotechnologie (VIB), Pleinlaan 2, Brussels 1050, Belgium.; Jean Jeener NMR Centre, Vrije Universiteit Brussel (VUB), Pleinlaan 2, Brussels 1050 Belgium., Stark M; Institute for Molecular Microbiology and Biotechnology, University of Münster, Corrensstr. 3, Münster 48149, Germany., Hölscher L; Institute for Molecular Microbiology and Biotechnology, University of Münster, Corrensstr. 3, Münster 48149, Germany., Steinert K; Institute for Food Chemistry, University of Münster, Corrensstr. 45, Münster 48149, Germany., Fetzner S; Institute for Molecular Microbiology and Biotechnology, University of Münster, Corrensstr. 3, Münster 48149, Germany., Hennecke U; Organic Chemistry Research Group, Department of Chemistry and Department of Bioengineering Sciences, Vrije Universiteit Brussel (VUB), Pleinlaan 2, Brussels 1050, Belgium., Drees SL; Institute for Molecular Microbiology and Biotechnology, University of Münster, Corrensstr. 3, Münster 48149, Germany. |
| Abstrakt: |
Synthesis of azetidine-derived natural products by the opportunistic pathogen Pseudomonas aeruginosa is controlled by quorum sensing, a process involving the production and sensing of diffusible signal molecules that is decisive for virulence regulation. In this study, we engineered P. aeruginosa for the titratable expression of the biosynthetic aze gene cluster, which allowed the purification and identification of two new products, azetidomonamide C and diazetidomonapyridone. Diazetidomonapyridone was shown to have a highly unusual structure with two azetidine rings and an open-chain diimide moiety. Expression of aze genes strongly increased biofilm formation and production of phenazine and alkyl quinolone virulence factors. Further physiological studies revealed that all effects were mainly mediated by azetidomonamide A and diazetidomonapyridone, whereas azetidomonamides B and C had little or no phenotypic impact. The P450 monooxygenase AzeF which catalyzes a challenging, stereoselective hydroxylation of the azetidine ring converting azetidomonamide C into azetidomonamide A is therefore crucial for biological activity. Based on our findings, we propose this group of metabolites to constitute a new class of diffusible regulatory molecules with community-related effects in P. aeruginosa . |
