Molecular interactions of bacterial autoinducer signals with target receptors: importance of signal molecule structure

Status: 
Complete
Investigators: 
Alan W. Decho (PI), P. Lee Ferguson (co-PI), John L. Ferry (co-PI), and S. Michael Angel (co-PI)
Funding Agency: 
US NSF Collaborative Research in Chemistry (CRC)

Inter-cellular communication in bacterial communities is often mediated through synthesis, release, and uptake of signaling molecules in a process termed quorum sensing.  The signals are taken up by cells and bind to protein receptors, which act as ligand-dependent transcription factors in activating regulated gene expression.  One important class of signals is the acyl homoserine lactone (AHL) series.  In environmental systems, these signaling molecules are subject to oxidative processes such as photolysis and hydrolysis.  We are examining how environmentally-mediated chemical modifications of AHLs alter the binding of these molecules to recombinant receptors from the model bacterium Vibrio fischeri.  For this work we are utilizing surface plasmon resonance (SPR) spectroscopy to characterize signal-receptor affinity and binding kinetics in vitro.