The effect of Staphylococcus epidermidis cells on Pseudomonas aeruginosa-associated virulence factors

Staphylococcus epidermidis and Pseudomonas aeruginosa are the two most commonly detected bacteria. Pseudomonas aeruginosa exerts significant impacts on pathogenesis through quorum-sensing regulation, while S. epidermidis role has always remained a matter of interest due to its frequent presence in most of the hospitalized samples and even inside the body during operation procedures. In this study, the effect of S. epidermidis cells on P. aeruginosa pathogenesis was analyzed. The effect of S. epidermidis cells on P. aeruginosa growth was analyzed by using microtiter plate assay, Colony forming unit (CFU), and microscopy. The effect of virulence factors including protease, rhamnolipid, and swarming motility was also investigated. Escherichia coli pJN105LpSC11, a bioreporter strain, was used to analyze the effect of S. epidermidis on P. aeruginosa quorum-sensing. The growth of P. aeruginosa did not affect S. epidermidis cells of 5.5x109, 6x109, 7x109, 8.5x109, and 1.5x1010 CFU/ml, and microscopy results are consistent with the findings. P. aeruginosaassociated virulence factors show that with increasing S. epidermidis counts, P. aeruginosa-associated virulence factors were reduced. No effect of S. epidermidis on P. aeruginosa quorum-sensing was observed. The outcomes suggest that S. epidermidis can be used as an alternative to reduce Pseudomonas aeruginosaassociated virulence factors and its pathogenesis.