Abstract:
The intestinal microbiome during infancy and childhood has distinct metabolic functions and microbial composition compared to adults. We recently published a gnotobiotic mouse model of the pre-weaning microbiome (PedsCom), which retains a pre-weaning configuration during the transition from a milk-based diet to solid foods, leads to a stunted immune system, and increases susceptibility to enteric infection. Here, we compared the phylogenetic and metabolic relationships of the PedsCom consortium to two adult-derived gnotobiotic communities, Altered Schaedler Flora and Oligo-Mouse Microbiota 12 (Oligo-MM12). We find that PedsCom contains several unique functions relative to these adult-derived mouse consortia, including differences in carbohydrate and lipid metabolism genes. Notably, amino acid degradation metabolic modules are more prevalent among PedsCom isolates, which is in line with the ready availability of these nutrients in milk. Indeed, metabolomic analysis revealed significantly lower levels of total free amino acids and lower levels of specific amino acids abundant in milk (e.g. glutamine and glutamic acid) in the intestinal contents of adult PedsCom colonized mice compared to Oligo-MM12 controls. Metabolomic analysis of pre-weaning intestinal contents also showed lower levels of amino acids that are replete in milk compared to germ-free controls. Thus, enhanced amino acid metabolism is a prominent feature of the pre-weaning microbiome that may facilitate design of early-life microbiome interventions.
摘要:
与成人相比,婴儿期和儿童期的肠道微生物组具有不同的代谢功能和微生物组成。我们最近发表了一个断奶前微生物组的老生症小鼠模型(PedsCom),在从基于牛奶的饮食过渡到固体食物的过程中,它保留了断奶前的配置,导致免疫系统发育迟缓,并增加对肠道感染的易感性。这里,我们比较了PedsCom财团的系统发育和代谢关系与两个成人来源的侏儒群落,改变Schaedler植物群和Oligo-Mouse微生物群12(Oligo-MM12)。我们发现PedsCom相对于这些成年小鼠聚生体包含几种独特的功能,包括碳水化合物和脂质代谢基因的差异。值得注意的是,氨基酸降解代谢模块在PedsCom分离株中更为普遍,这符合牛奶中这些营养素的现成可用性。的确,代谢组学分析显示,与Oligo-MM12对照相比,成年PedsCom定植小鼠的肠内容物中的总游离氨基酸水平显着降低,牛奶中丰富的特定氨基酸(例如谷氨酰胺和谷氨酸)水平降低。断奶前肠内容物的代谢组学分析还显示,与无菌对照相比,牛奶中富含的氨基酸水平较低。因此,增强的氨基酸代谢是断奶前微生物组的一个突出特征,这可能有助于设计早期生命微生物组干预措施.