Staphylococcus xylosus, a coagulase-negative Staphylococcus, is frequently isolated from food products of animal origin and used as a starter culture in these products in which it contributes to their flavour, while Staphylococcus aureus, a coagulase-positive bacterium, causes foodborne intoxication and is implicated in a broad diversity of infections in medical sector, notably in nosocomial infections. S. xylosus and S. aureus are both capable of forming a biofilm and share the same ecological niches, thus we explored their interaction in biofilms with a view to limiting the risks associated with S. aureus. Cell-free supernatants of different strains of S. xylosus were able to inhibit the biofilm formation of S. aureus. The S. xylosus C2a strain released into the supernatant a molecule of molecular weight above 30 kDa that is resistant to proteolytic enzymes and inhibits the formation of S. aureus MW2 biofilm, though the mechanism involved has yet to be elucidated. Furthermore, S. xylosus C2a modified the architecture of S. aureus MW2 in co-culture biofilm. Confocal laser scanning microscopy revealed that S. aureus formed a biofilm with a flat and compact structure while in co-culture with S. xylosus the two species formed large juxtaposed aggregates throughout the period of incubation. This architecture made the S. aureus biofilm more susceptible to detachment.

中文翻译：

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葡萄球菌和金黄色葡萄球菌之间的双重物种生物膜的相互作用。

木糖葡萄球菌是一种凝固酶阴性葡萄球菌，通常从动物源食品中分离出来，并用作这些产品中的发酵剂，有助于其风味，而凝固酶阳性细菌金黄色葡萄球菌引起食源性中毒，是与医疗部门的多种感染有关，尤其是医院感染。木糖链霉菌和金黄色葡萄球菌都能够形成生物膜并共享相同的生态位，因此我们探索了它们在生物膜中的相互作用，以限制与金黄色葡萄球菌相关的风险。木糖链球菌不同菌株的无细胞上清液能够抑制金黄色葡萄球菌的生物膜形成。S. xylosus C2a菌株释放到上清液中的分子量大于30 kDa的分子对蛋白水解酶具有抵抗力，并抑制金黄色葡萄球菌MW2生物膜的形成，尽管所涉及的机制尚未阐明。此外，木糖链球菌C2a修改了共培养生物膜中金黄色葡萄球菌MW2的结构。共聚焦激光扫描显微镜显示，金黄色葡萄球菌形成了具有平坦而紧凑结构的生物膜，而在与木糖酵母的共培养过程中，这两个物种在整个培养过程中形成了并列的大聚集体。这种结构使金黄色葡萄球菌生物膜更容易脱落。共培养生物膜中的金黄色素MW2。共聚焦激光扫描显微镜显示，金黄色葡萄球菌形成了具有平坦而紧凑结构的生物膜，而在与木糖酵母的共培养过程中，这两个物种在整个孵育过程中形成了并列的大聚集体。这种结构使金黄色葡萄球菌生物膜更容易脱落。共培养生物膜中的金黄色素MW2。共聚焦激光扫描显微镜显示，金黄色葡萄球菌形成了具有平坦而紧凑结构的生物膜，而在与木糖酵母的共培养过程中，这两个物种在整个孵育过程中形成了并列的大聚集体。这种结构使金黄色葡萄球菌生物膜更容易脱落。