In the context of infection, Pseudomonas aeruginosa and Staphylococcus aureus are frequently co-isolated, particularly in cystic fibrosis (CF) patients. Within lungs, the two pathogens exhibit a range of competitive and coexisting interactions. In the present study, we explored the impact of S. aureus on the physiology of P. aeruginosa in the context of coexistence. Transcriptomic analyses showed that S. aureus significantly and specifically affects the expression of numerous genes involved in P. aeruginosa carbon and amino acid metabolism. In particular, 65% of the strains presented considerable overexpression of the genes involved in the acetoin catabolic (aco) pathway. We demonstrated that acetoin is (i) produced by clinical S. aureus strains, (ii) detected in sputa from CF patients and (iii) involved in P. aeruginosa’s aco system induction. Furthermore, acetoin is catabolized by P. aeruginosa, a metabolic process that improves the survival of both pathogens by providing a new carbon source for P. aeruginosa and avoiding the toxic accumulation of acetoin on S. aureus. Due to its beneficial effects on both bacteria, acetoin catabolism could testify to the establishment of trophic cooperation between S. aureus and P. aeruginosa in the CF lung environment, thus promoting their persistence.

在感染的情况下，铜绿假单胞菌和金黄色葡萄球菌经常共同分离，尤其是在囊性纤维化 (CF) 患者中。在肺部，这两种病原体表现出一系列竞争性和共存的相互作用。在本研究中，我们探讨了金黄色葡萄球菌在共存背景下对铜绿假单胞菌生理的影响。转录组学分析表明，金黄色葡萄球菌显着且特异性地影响参与铜绿假单胞菌碳和氨基酸代谢的众多基因的表达。特别是，65% 的菌株表现出相当多的参与乙偶姻分解代谢的基因（aco) 途径。我们证明了乙偶姻（i）由临床金黄色葡萄球菌菌株产生，（ii）在 CF 患者的痰中检测到，以及（iii）参与铜绿假单胞菌的aco系统诱导。此外，乙偶姻被铜绿假单胞菌分解代谢，这一代谢过程通过为铜绿假单胞菌提供新的碳源并避免乙偶姻在金黄色葡萄球菌上的毒性积累来提高两种病原体的存活率。由于其对两种细菌的​​有益作用，乙偶姻分解代谢可以证明金黄色葡萄球菌和铜绿假单胞菌之间建立了营养合作 在 CF 肺环境中，从而促进它们的持久性。