Laboratory of Food Biotechnology, Department of Health Sciences and Technology, Institute of Food, Nutrition and Health, ETH-Zurich, 8092 Zurich, Switzerland.
Division of Gastroenterology and Nutrition, University Children's Hospital Zurich, 8032 Zurich, Switzerland.
FEMS Microbiol Ecol. 2019 Jan 1;95(1). doi: 10.1093/femsec/fiy215.
Establishment of the infant gut microbiota affects gut maturation and influences long-term health. Cutibacterium (formerly Propionibacterium) have been identified as early colonizers, but little is known about their function. Using a cultivation-dependent and -independent approach, we determined Cutibacterium prevalence, diversity and functional potential. In feces from a Swiss infant cohort (n = 38), prevalence of Propionibacterium/Cutibacterium decreased from 84% at 2 weeks, to 65% at 4 weeks, 47% at 8 weeks and 41% at 12 weeks of age. Abundance varied among individuals, and persistence depended on the colonization levels at 2 weeks. Cutibacterium isolates (n = 87) were obtained from 10 infants from a smaller cohort (n = 12); restriction fragment length polymorphism clustered isolates in four groups, and all identified as Cutibacterium avidum. Colonization potential and metabolic effects of C. avidum addition were tested in an in vitro continuous intestinal fermentation model mimicking infant proximal colon conditions. Cutibacterium avidum spiked daily at 108 or 109 cells mL-1 colonized, decreased formate and persisted during the washout period. Significant correlations were observed between Propionibacterium/Cutibacterium and lactate-producers and protein-degraders in both reactors and infant feces. Our findings highlight the natural presence of C. avidum and its role as a lactate-consumer and propionate-producer in infants younger than 3 months.
婴儿肠道微生物群的建立会影响肠道成熟，并影响长期健康。表皮葡萄球菌（以前称为丙酸杆菌属）已被确定为早期定植菌，但它们的功能知之甚少。我们采用培养依赖和非依赖的方法，确定了表皮葡萄球菌的流行率、多样性和功能潜力。在瑞士婴儿队列（n=38）的粪便中，丙酸杆菌/表皮葡萄球菌的患病率从 2 周时的 84%下降到 4 周时的 65%、8 周时的 47%和 12 周时的 41%。个体之间的丰度存在差异，定植的持久性取决于 2 周时的定植水平。从小队列（n=12）的 10 名婴儿中获得了 87 个表皮葡萄球菌分离株（n=87）；限制性片段长度多态性将分离株聚类为 4 组，均鉴定为贪食丙酸杆菌。在模拟婴儿近端结肠条件的体外连续肠道发酵模型中，测试了 C.avidum 的定植潜力和代谢作用。每天以 108 或 109 个细胞 mL-1 的浓度添加 C.avidum 进行定植，减少了甲酸盐并在冲洗期内持续存在。在两个反应器和婴儿粪便中，均观察到丙酸杆菌/表皮葡萄球菌与乳酸产生菌和蛋白质降解菌之间存在显著相关性。我们的研究结果强调了 C.avidum 的自然存在及其在 3 个月以下婴儿中作为乳酸消耗菌和丙酸产生菌的作用。
