Competitive inhibition and mutualistic growth in co-infections: deciphering interaction dynamics.

and are frequently co-isolated from polymicrobial infections that are severe and refractory to therapy. Here, we apply a combination of wet-lab experiments and modeling to unveil the intricate nature of the / interaction using both, representative laboratory strains and strains co-isolated from clinical samples. This comprehensive methodology allowed uncovering capability to exert a partial interference on by the expression of phenol-soluble modulins. In addition, we observed a cross-feeding mechanism by which supports the growth of by providing acetoin as an alternative carbon source. This study is the first to dissect the / interaction dynamics wherein competitive and cooperative strategies can intertwine. Through our findings, we illuminate the ecological mechanisms supporting their coexistence in the context of polymicrobial infections. Our research not only enriches our understanding but also opens doors to potential therapeutic avenues in managing these challenging infections.