Truncated auto-inducing peptides as antagonists of Staphylococcus lugdunensis quorum sensing

Competitive quorum sensing antagonisim (QS) offers a novel strategy for attenuating current multi-drug resistant staphylococcal infections. To this end, a series of 10 truncated analogues based on the parent auto-inducing peptides (AIPs) of Staphylococcus lugdunensis (group I & II) and Staphylococcus epidermidis (groups I – III) were sequentially assessed against a newly developed Staphylococcus lugdunensis group I QS reporter strain. The truncated analogues based upon Staphylococcus lugdunensis AIP-1 (1) and AIP-2 (2) displayed respective IC50 values of 0.2 ± 0.01 μM and 0.3 ± 0.01 μM whilst the truncated analogue of the S Staphylococcus. epidermidis AIP-1 (3) elicited an IC50 value of 2.7± 0.1 μM. These findings demonstrate the potential of cognate and ‘cross-talk’ competitive quorum sensing inhibition using truncated AIPs as a means of attenuating staphylococcal infections in species beyond Staphylococcus aureus.