张和平等Microbiome：母乳源益生菌Probio-M8可通过哺乳经口腔/肠道-乳腺轴垂直传递到婴儿肠道

Microbiome[IF:16.837]

① 纳入哺乳期健康母婴志愿者，母亲口服Probio-M8菌粉，通过培养组从母亲粪便、母乳和婴儿粪便中均分离出Probio-M8同源株，表明Probio-M8可通过哺乳经过口腔/肠道-乳腺轴垂直传递给婴儿；

② 从母婴粪便宏基因组数据中组装出Probio-M8同源株，再次证明Probio-M8可实现母婴间垂直传递；

③ 在母婴分离的同源株中发现编码葡萄糖转运蛋白基因glcU高频突变，表型鉴定发现该基因突变株对碳源代谢能力增强，表明Probio-M8在肠道中发生了适应性进化。

Bifidobacterium animalis subsp. lactis Probio-M8 undergoes host adaptive evolution by glcU mutation and translocates to the infant’s gut via oral-/entero-mammary routes through lactation
11-22, doi: 10.1186/s40168-022-01398-6

【主编评语】以往大多数试图证明母婴间菌群传递现象的研究都是观察性，仅在属/种水平分辨率下进行，并且完全依赖于非培养组的方法，这些问题阻碍了针对婴儿肠道菌群靶向调节其生理及健康的策略。近日，内蒙古农业大学张和平团队在Microbiome上发表最新研究，以乳双歧杆菌Probio-M8作为生物标记菌株，通过分离、培养和特定菌株的生化表征等综合功能分析来充分验证菌群在母婴间垂直传递。结果发现母亲摄入的Probio-M8可以通过口腔-肠道-乳腺途径转移到婴儿肠道，这表明通过哺乳用双歧杆菌和其他可能的益生菌喂养婴儿是可行的。总之，该研究提供了关于母乳菌群对婴儿肠道定植影响的独特见解，也为未来新生儿补充母乳源益生菌提供了新的策略。

Bifidobacterium animalis subsp. lactis Probio-M8 undergoes host adaptive evolution by glcU mutation and translocates to the infant’s gut via oral-/entero-mammary routes through lactation

乳双歧杆菌Probio‑M8通过glcU进行宿主突变适应性进化，在哺乳期借助口腔-肠道-乳腺途径转移到婴儿肠道

10.1186/s40168-022-01398-6

11-22, Article

Abstract:
Background: Most previous studies attempting to prove the phenomenon of mother-to-infant microbiota transmission were observational, performed only at genus/species-level resolution, and relied entirely on non-culture-based methodologies, impeding interpretation.
Results: This work aimed to use a biomarker strain, Bifidobacterium animalis subsp. lactis Probio-M8 (M8), to directly evaluate the vertical transmission of maternally ingested bacteria by integrated culture-dependent/-independent methods. Our culture and metagenomics results showed that small amounts of maternally ingested bacteria could translocate to the infant gut via oral-/entero-mammary routes through lactation. Interestingly, many mother-infant-pair-recovered M8 homologous isolates exhibited high-frequency nonsynonymous mutations in a sugar transporter gene (glcU) and altered carbohydrate utilization preference/capacity compared with non-mutant isolates, suggesting that M8 underwent adaptive evolution for better survival in simple sugar-deprived lower gut environments.
Conclusions: This study presented direct and strain-level evidence of mother-to-infant bacterial transmission through lactation and provided insights into the impact of milk microbiota on infant gut colonization.

First Authors:
Zhi Zhong,Hai Tang

Correspondence Authors:
Heping Zhang

All Authors:
Zhi Zhong,Hai Tang,Tingting Shen,Xinwei Ma,Feiyan Zhao,Lai-Yu Kwok,Zhihong Sun,Menghe Bilige,Heping Zhang