Ghent University. Faculty of Bioscience Engineering
Abstract
In this PhD thesis isotope-labelled AHLs were synthesized which can be used as a tool to study the metabolization of AHLs. Secondly, the possible rearrangement of N-(3-hydroxyacyl)- L-homoserine lactones was investigated and proven to be very unlikely. This investigation resulted in the successful development of a synthetic entry toward 1,4-oxazepane-2,5-diones, which are extremely difficult to synthesize due to the presence of a lactam with a preference for the trans-conformation and a labile lactone moiety in one ring structure. By applying the disclosed methodology on the synthesis of the natural product serratin, the incorrect structural assignment of this compound was identified. Thirdly, the profound effect of a QS signal molecule, HO8, on the swarming behavior of Pseudomonas species CMR12a, was demonstrated. This influence goes presumably via an elegant fine-tuning of the ratio of the two produced CLPs, orfamide and sessilin via the control of orfamide production