Lee Wei H, Oglesby Amanda G, Nolan Elizabeth M
Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.
Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Maryland, USA.
mSystems. 2025 Sep 4:e0057625. doi: 10.1128/msystems.00576-25.
and cause debilitating polymicrobial infections in diverse patient populations. Studies of these bacterial pathogens in coculture have shown that environmental variables, including Fe availability and the host-defense protein calprotectin (CP), impact coculture dynamics. To decipher how CP modulates interactions between and , we employed dual-species RNA-seq to examine the transcriptional responses of both pathogens in coculture to CP treatment and metal depletion. Analysis of these responses revealed that, for both and , CP treatment not only induced gene expression changes consistent with single- and multi-metal starvation responses but also induced gene expression changes that were not observed under metal limitation. For , CP treatment induced gene expression changes pointing to a shift in chorismate flux away from alkylquinolone and phenazine biosynthesis and toward folate biosynthesis. These observations were consistent with decreased production of alkylquinolones by , including the potent anti-staphylococcal alkylquinolone N-oxides. CP treatment altered the levels of two quorum-sensing molecules, 3-oxo-C-homoserine lactone and C-homoserine lactone, produced by . In addition, CP treatment enhanced the ability of to mount Fe-starvation responses and caused to express host virulence genes. This analysis illuminated the physiological consequences of CP treatment that extend beyond metal starvation and impact interspecies interactions. Our findings provide a working model in which CP effectively disarms by inhibiting the production of anti-staphylococcal factors and boosts the ability of to protect itself from attack.IMPORTANCEThe innate immune protein calprotectin (CP) defends the host against bacterial pathogens by sequestering multiple essential nutrient metal ions at infection sites. In addition to this role in nutritional immunity, CP promotes the survival of in coculture with , an effect that is independent of its metal-sequestering function. In this work, we sought to understand how CP modulates this interspecies interaction by evaluating the transcriptional responses of and to CP and metal limitation in cocultures. Our study revealed that CP attenuates the ability of to attack with anti-staphylococcal factors and enhances the capacity of to withstand this assault, effects that are not recapitulated by metal limitation. This work provides a new understanding of how CP modulates microbial interactions that are relevant to human health.
并在不同患者群体中引发使人衰弱的多种微生物感染。对这些细菌病原体进行共培养研究表明，包括铁可用性和宿主防御蛋白钙卫蛋白（CP）在内的环境变量会影响共培养动态。为了解CP如何调节[具体细菌名称1]和[具体细菌名称2]之间的相互作用，我们采用双物种RNA测序来检测共培养中两种病原体对CP处理和金属缺乏的转录反应。对这些反应的分析表明，对于[具体细菌名称1]和[具体细菌名称2]而言，CP处理不仅诱导了与单金属和多金属饥饿反应一致的基因表达变化，还诱导了在金属限制条件下未观察到的基因表达变化。对于[具体细菌名称1]，CP处理诱导的基因表达变化表明分支酸通量从烷基喹诺酮和吩嗪生物合成转向叶酸生物合成。这些观察结果与[具体细菌名称1]产生的烷基喹诺酮减少一致，包括强效抗葡萄球菌烷基喹诺酮N - 氧化物。CP处理改变了[具体细菌名称2]产生的两种群体感应分子3 - 氧代 - C - 高丝氨酸内酯和C - 高丝氨酸内酯的水平。此外，CP处理增强了[具体细菌名称2]引发铁饥饿反应的能力，并使[具体细菌名称2]表达宿主毒力基因。该分析揭示了CP处理的生理后果，其超出了金属饥饿的范畴并影响种间相互作用。我们的研究结果提供了一个工作模型，其中CP通过抑制抗葡萄球菌因子的产生有效地解除了[具体细菌名称1]的武装，并增强了[具体细菌名称2]保护自身免受攻击的能力。
先天性免疫蛋白钙卫蛋白（CP）通过在感染部位螯合多种必需营养金属离子来保护宿主免受细菌病原体侵害。除了在营养免疫中的这一作用外，CP还促进了[具体细菌名称2]与[具体细菌名称1]共培养时的存活，这一效应与其金属螯合功能无关。在这项工作中，我们试图通过评估[具体细菌名称1]和[具体细菌名称2]在共培养中对CP和金属限制的转录反应来了解CP如何调节这种种间相互作用。我们的研究表明，CP减弱了[具体细菌名称1]用抗葡萄球菌因子攻击[具体细菌名称2]的能力，并增强了[具体细菌名称2]抵御这种攻击的能力，而金属限制并未重现这些效应。这项工作为CP如何调节与人类健康相关的微生物相互作用提供了新的认识。
