Pseudomonads produce antimicrobial or cytotoxic cyclic lipopeptides (CLPs) and quorum sensing signal molecules, i.e. N-acyl homoserine lactones (AHLs) as interesting secondary metabolites. The overall goal is a) the identification of the role of AHL-mediated quorum sensing mechanisms in regulating secondary metabolite production (CLPs) and b) the elucidtation of fatty acid-based biosynthetic pathways and SAR of CLPs.