Microbiome Dynamics, Leibniz Institute for Natural Product Research and Infection Biology- Hans Knöll Institute, Jena, Germany.
National Koranyi Institute of Pulmonology, Budapest, Hungary.
Nat Commun. 2023 May 9;14(1):2673. doi: 10.1038/s41467-023-38058-8.
Candida species overgrowth in the human gut is considered a prerequisite for invasive candidiasis, but our understanding of gut bacteria promoting or restricting this overgrowth is still limited. By integrating cross-sectional mycobiome and shotgun metagenomics data from the stool of 75 male and female cancer patients at risk but without systemic candidiasis, bacterial communities in high Candida samples display higher metabolic flexibility yet lower contributional diversity than those in low Candida samples. We develop machine learning models that use only bacterial taxa or functional relative abundances to predict the levels of Candida genus and species in an external validation cohort with an AUC of 78.6-81.1%. We propose a mechanism for intestinal Candida overgrowth based on an increase in lactate-producing bacteria, which coincides with a decrease in bacteria that regulate short chain fatty acid and oxygen levels. Under these conditions, the ability of Candida to harness lactate as a nutrient source may enable Candida to outcompete other fungi in the gut.
人体肠道中念珠菌属过度生长被认为是侵袭性念珠菌病的先决条件，但我们对促进或限制这种过度生长的肠道细菌的了解仍然有限。通过整合来自 75 名男性和女性癌症患者的粪便的横断面真菌组和 shotgun 宏基因组学数据，这些患者有侵袭性念珠菌病的风险但没有系统性念珠菌病，高念珠菌样本中的细菌群落显示出比低念珠菌样本更高的代谢灵活性，但贡献多样性更低。我们开发了机器学习模型，仅使用细菌分类群或功能相对丰度来预测外部验证队列中念珠菌属和种的水平，AUC 为 78.6-81.1%。我们提出了一种基于产乳酸细菌增加的肠道念珠菌过度生长的机制，这与调节短链脂肪酸和氧气水平的细菌减少相吻合。在这些条件下，念珠菌利用乳酸作为营养源的能力可能使念珠菌能够在肠道中与其他真菌竞争。
