biostudies-literatureTimme SIntegrated Research and Treatment Center—Center for Sepsis Control and CareDeutsche ForschungsgemeinschaftPhotonics Research GermanyProject Leibniz Center for Photonics in Infection ResearchNational Institutes of HealthEXC 2155NIHNIGMS NIH HHSADAGerman Network for Bioinformatics InfrastructureGerman Federal Ministry of Education and Researchycae077https://www.ebi.ac.uk/biostudies/studies/S-EPMC11221087biostudies-literatureUnknown4(1)<i>Staphylococcus aureus (Sa)</i> and <i>Acinetobacter baumannii (Ab)</i> are frequently co-isolated from polymicrobial infections that are severe and refractory to therapy. Here, we apply a combination of wet-lab experiments and <i>in silico</i> modeling to unveil the intricate nature of the <i>Ab</i>/<i>Sa</i> interaction using both, representative laboratory strains and strains co-isolated from clinical samples. This comprehensive methodology allowed uncovering <i>Sa's</i> capability to exert a partial interference on <i>Ab</i> by the expression of phenol-soluble modulins. In addition, we observed a cross-feeding mechanism by which <i>Sa</i> supports the growth of <i>Ab</i> by providing acetoin as an alternative carbon source. This study is the first to dissect the <i>Ab</i>/<i>Sa</i> iISME communicationsCompetitive inhibition and mutualistic growth in co-infections: deciphering <i>Staphylococcus aureus-Acinetobacter baumannii</i> interaction dynamics.PMC1122108739087428001K1230613N15717SC3GM125556444711651FKZ032A532BJPIAMR2022-07039071386013GW0456SC3 GM12555601EO150213N15709Rodel JWendler SSchramm SEhricht RLoffler BEdel BTimme STuchscherr LMonecke SWittchen MSlevogt HSaraiva JPRamirez MSFigge MTKlassert TEda Rocha UNfalseCompetitive inhibition and mutualistic growth in co-infections: deciphering <i>Staphylococcus aureus-Acinetobacter baumannii</i> interaction dynamics.<i>Staphylococcus aureus (Sa)</i> and <i>Acinetobacter baumannii (Ab)</i> are frequently co-isolated from polymicrobial infections that are severe and refractory to therapy. Here, we apply a combination of wet-lab experiments and <i>in silico</i> modeling to unveil the intricate nature of the <i>Ab</i>/<i>Sa</i> interaction using both, representative laboratory strains and strains co-isolated from clinical samples. This comprehensive methodology allowed uncovering <i>Sa's</i> capability to exert a partial interference on <i>Ab</i> by the expression of phenol-soluble modulins. In addition, we observed a cross-feeding mechanism by which <i>Sa</i> supports the growth of <i>Ab</i> by providing acetoin as an alternative carbon source. This study is the first to dissect the <i>Ab</i>/<i>Sa</i> i2024-01-01T00:00:00Z2024 Jan2026-06-03T00:25:12.085Z2025-04-06T00:11:58.186ZS-EPMC112210873896249410.1093/ismeco/ycae077