Staphylococcus aureus coinfection

The present work comprises the study of wound pathogenic bacteria as part of a community. It considers the interactions of two different S. aureus isolates with B. thuringiensis and K. oxytoca; all of them isolated from the same chronic wound of a patient with epidermolysis bullosa. Particular focus has been given on the interactions of S. aureus with other microbes due to its high prevalence among chronic wounds. During cultivation, no species performed as dominant or inhibited the growth of one another. Mass spectrometry was used to explore the inherent relationships between the staphylococcal strains and the coexisting bacteria exproteomes. The analysis showed an important reduction in the amount of staphylococcal cytoplasmic proteins when co-cultured with K. oxytoca and B. thuringiensis, this decrement did not occur with klebsiella and bacillus proteins. Interestingly, K. oxytoca and B. thuringiensis seemed to have a more evident response towards the presence of S. aureus in the culture, while the opposite was not observed with the staphylococcal isolates. Genomic analysis revealed isolate t13595 hypermutable characteristics, placing the interactions between staphylococcal isolates in the context of a chronic wound. Overall, the nature of the exoproteome variations among cultures suggests that adaptive mechanisms differ in all strains.