Bifidobacteria are important probiotics; some of the beneficial effects of bifidobacteria are achieved by the hydrolysis of glycans in the human gut. However, because the diet of breastfed infants typically lacks plant-derived glycans, in the gut environment of mothers and their breastfed infants, the mother will intake a variety of plant-derived glycans, such as from onions and bananas, through her diet. Under this assumption, we are interested in whether the same species of bifidobacteria isolated from mother-infant pairs present a distinction in their hydrolysis of plant-derived carbohydrates. Among the 36 Bifidobacterium strains, bifidobacterial carbohydrate utilization showed two trends related to the intestinal environment where the bacteria lived. Compared with infant-type bifidobacterial strains, adult-type bifidobacterial strains preferred to use plant-derived glycans. Of these strains, 10 isolates, 2 Bifidobacterium pseudocatenulatum (B. pseudocatenulatum), 2 Bifidobacterium pseudolongum (B. pseudolongum), 2 Bifidobacterium bifidum (B. bifidum), 2 Bifidobacterium breve (B. breve), and 2 Bifidobacterium longum (B. longum), were shared between the mother-infant pairs. Moreover, the repetitive sequence-based polymerase chain reaction (rep-PCR) results illustrated that B. pseudolongum and B. bifidum showed genotypic similarities of 95.3 and 98.2%, respectively. Combined with the carbohydrate fermentation study, these results indicated that the adult-type strains have a stronger ability to use plant-derived glycans than infant-type strains. Our work suggests that bifidobacterial carbohydrate metabolism differences resulted in the selective adaptation to the distinct intestinal environment of an adult or breastfed infant. The present study revealed that the different gut environments can lead to the differences in the polysaccharide utilization in the same strains of bifidobacterial strains, suggesting a further goal of investigating the exact expression of certain enzymes in response to specific carbon sources.

中文翻译：

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母婴双歧杆菌菌株的基因分型和植物来源的聚糖利用分析。

双歧杆菌是重要的益生菌；双歧杆菌的一些有益作用是通过水解人体肠道中的聚糖来实现的。然而，由于母乳喂养婴儿的饮食通常缺乏植物来源的聚糖，在母亲及其母乳喂养婴儿的肠道环境中，母亲会通过饮食摄入多种植物来源的聚糖，例如洋葱和香蕉。在这种假设下，我们感兴趣的是从母婴对中分离出的相同种类的双歧杆菌是否在植物来源的碳水化合物水解方面存在差异。在 36 种双歧杆菌菌株中，双歧杆菌碳水化合物的利用显示出两种与细菌生活的肠道环境相关的趋势。与婴儿型双歧杆菌相比，成人型双歧杆菌菌株更喜欢使用植物来源的聚糖。在这些菌株中，有 10 个分离株，2 个假链状双歧杆菌 (B.pseudocatenulatum)、2 个假长双歧杆菌 (B.pseudolongum)、2 个双歧杆菌 (B. bifidum)、2 个短双歧杆菌 (B. breve) 和 2 个长双歧杆菌 (B. longum），在母婴之间共享。此外，基于重复序列的聚合酶链反应 (rep-PCR) 结果表明假长双歧杆菌和双歧双歧杆菌分别显示 95.3% 和 98.2% 的基因型相似性。结合碳水化合物发酵研究，这些结果表明，成人型菌株比婴儿型菌株具有更强的利用植物来源聚糖的能力。我们的工作表明，双歧杆菌碳水化合物代谢差异导致对成人或母乳喂养婴儿不同肠道环境的选择性适应。目前的研究表明，不同的肠道环境会导致相同双歧杆菌菌株中多糖利用的差异，这表明进一步研究某些酶响应特定碳源的确切表达的目标。