Mechanisms of Corynebacterium-Dolosigranulum Interactions that Shape Human Nasal Microbiota

将NIGMS资助的两个研究领域统一起来的目的是确定 微小革兰氏菌和鼻棒状杆菌的微生物和宿主相互作用 塑造人类鼻部微生物区系。有证据表明，棒状杆菌物种和Dolosigranulum 鼻底在构建有益于人类健康的鼻部微生物区系中起着关键作用。例如，患有高血压病的人 鼻腔微生物区系中棒状杆菌和/或软棒状杆菌的水平不太可能被病原体定植。 因此，他们身体其他部位受到侵袭性感染的风险较低。同样，鼻部微生物区系 由棒状杆菌/D.pgrum主宰的细菌通常与健康有关，而不是与疾病有关，如 中耳炎和肺炎。我们的最重要的假设是，石斑菌和石斑菌之间的相互作用 棒状杆菌物种推动了有益于健康的人类鼻部微生物群的形成。这样做的一个中心目标是 研究将通过识别分子机制，从成分数据的相关性转向因果关系 这是体内关联和体外表型的基础。我们由NIGMS支持的初步数据显示 有四种常见的鼻棒状杆菌。其中有三种细菌与小球藻呈正相关。 和促进石斑菌的体外生长。此外，还利用棒状杆菌共培养的方法研究了木霉与棒状杆菌的共培养。 与单独使用相比，假白喉杆菌在体外对肺炎链球菌有很强的抑制作用。D.pgrum也是 抑制金黄色葡萄球菌的体外生长。这些体外实验结果支持体内与潜在健康的相互作用。 福利。为了了解人类鼻道中微生物-微生物和微生物-上皮细胞的相互作用，我们 将在气液界面使用人类鼻腔上皮有机化合物(也称为鼻样物质)作为一种创新的仿生药物 与我们的有机体核心合作的模型系统。微生物群落的特征是 微生物之间以及与环境之间的代谢相互作用。基因组分析发现细小石斑菌 营养缺乏症表明它依赖于宿主或微生物邻居来获取关键营养物质。我们的研究将解决 在理解支持人类鼻部微生物区系的食物网方面的差距；对鼻部上皮的影响 寄生微生物；以及潜在有益的鼻部细菌的生理和功能。的一个关键优势 利用人鼻微生物区系鉴定代谢相互作用是一种自含式的细菌-上皮 关于营养素的系统。我们将使用互补的方法，包括泛基因组学、代谢 建模、细菌-上皮双重转录组学、代谢组学和基因工程。我们还将处理 鼻部微生物组领域的关键技术挑战，以促进代谢物、蛋白质和 参与相互作用的基因。为了促进对松材线虫和鼻棒状杆菌的研究，我们已经 从400名各个年龄段的志愿者身上收集了大量鼻腔细菌培养样本。通过识别代谢 鼻部棒状杆菌和鼻部上皮之间的相互作用-- 促进人类鼻部微生物区系的发展，我们希望催化预防感染的新方法。

The objective unifying our two areas of NIGMS-funded research is to identify molecular mechanisms underlying microbe-microbe and microbe-host interactions involving D. pigrum and nasal Corynebacterium species that shape the human nasal microbiota. Evidence indicates that Corynebacterium species and Dolosigranulum pigrum play key roles in structuring a nasal microbiota beneficial to human health. For example, people with high levels of Corynebacterium and/or D. pigrum in their nasal microbiota are less likely to be colonized by pathobionts and, therefore, are at lower risk of invasive infections in other parts of their bodies. Similarly, nasal microbiota dominated by Corynebacterium/D. pigrum are often associated with health rather than with diseases such as otitis media and pneumonia. Our overarching hypothesis is that interactions between D. pigrum and Corynebacterium species drive a beneficial health-promoting human nasal microbiota. A central goal of this research is to shift from correlations in compositional data to causation by identifying molecular mechanisms that underlie both in vivo associations and in vitro phenotypes. Our NIGMS-supported preliminary data show that there are four common species of nasal Corynebacterium. Three of these are positively correlated with D. pigrum and enhance D. pigrum growth in vitro. Furthermore, cocultivation of D. pigrum with Corynebacterium pseudodiphtheriticum together robustly inhibits S. pneumoniae in vitro, compared to either alone. D. pigrum also inhibits S. aureus growth in vitro. These in vitro results support a role for in vivo interactions with potential health benefits. To understand microbe-microbe and microbe-epithelium interactions in the human nasal passages, we will use human nasal epithelial organoids at an air-liquid interface (aka nasanoids) as an innovative biomimetic model system in collaboration with our Organoid Core. Microbial communities are characterized by a network of metabolic interactions among microbes and with the environment. Genomic analysis uncovered D. pigrum auxotrophies indicating it depends on the host or microbial neighbors for key nutrients. Our research will address gaps in understanding the food web that supports human nasal microbiota; the effects on the epithelium of hosting microbes; and the physiology and function of potentially beneficial nasal bacteria. A key advantage of using human nasal microbiota to identify metabolic interactions is that it is a self-contained bacterial-epithelial system with regard to nutrients. We will use complementary approaches including pan-genomics, metabolic modeling, dual bacteria-epithelium transcriptomics, metabolomics and genetic engineering. We will also tackle key technical challenges in the nasal microbiome field to facilitate identification of metabolites, proteins and genes involved in interactions. To advance research on D. pigrum and nasal Corynebacterium, we have established a large culture collection of nasal bacteria from > 400 volunteers of all ages. By identifying metabolic interactions between nasal Corynebacterium species, D. pigrum, and the nasal epithelium that sculpt a health- promoting human nasal microbiota, we hope to catalyze new approaches for preventing infection.