Bacterial quorum sensing: a new target for anti-infective immunotherapy

Cell-to-cell communication via exchange of small molecules, 'autoinducers', is a widespread phenomenon among Gram-negative and -positive bacteria. This intercellular signaling that synchronizes population-wide gene expression in a cell-density-dependent manner is termed 'quorum sensing' (QS). The discovery that Gram-negative bacteria employ non-peptide structures, N-acyl homoserine lactones, to globally regulate production of secondary metabolites and proteins, initiated a new area of research. Subsequently, other quorum-sensing systems and small signaling molecules were identified. With the emergence of antibiotic-resistant bacteria, most prominently methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa, new approaches for combating infections are needed. Inhibition of QS results in attenuation of virulence rather than direct killing of microbes.

We highlight current trends in preventing bacterial infections using quorum-quenching strategies.

We mainly focus on P. aeruginosa and S. aureus and their QS systems as targets for intervention.

New research strongly suggests that QS systems represent attractive targets for discovery of novel anti-infective agents, including immunotherapeutic strategies.