Binding events of (S)-N-(3-oxo-octanoyl)-homoserine Lactone with Agrobacterium tumefaciens mutant cells studied by saturation transfer difference NMR

Abstract

Quorum-sensing is a widely studied communication phenomenon in bacteria, which involves the production and detection of signaling substances in relation with cell density and colony behavior. Herein, the membrane binding interactions of the signal (S)-N-(3-oxo-octanoyl)-HSL with A. tumefaciens NTL4(pZLR4) cells were studied using saturation transfer difference NMR spectroscopy (STD-NMR). The substance epitope map was obtained showing that the hydrophobic acyl chain is the most important interacting site for the signal and the cell membrane. Results were interpreted upon comparisons with a simpler system, using liposomes as membrane models. Some insights on the use of β-cyclodextrin as acyl-HSL carrier were also provided. ©2011 Sociedade Brasileira de Química.