The enteric microbiota exerts a major influence on the host. It promotes food degradation, nutrient absorption, immune maturation and protects from infection with pathogenic microorganisms. However, certain compositional alterations also enhance the risk to develop metabolic, inflammatory and immune-mediated diseases. This suggests that the enteric microbiota is subject to strong evolutionary pressure. Here, we hypothesize that endogenous, genetically determined mechanisms exist that shape and optimize the enteric microbiota. We discuss that the postnatal period as the starting point of the host-microbial interaction bears the greatest chance to identify such regulatory mechanisms and report on two recently identified ways how the neonate host favours or disfavours colonization by certain bacteria and thereby manipulates the postnatally emerging bacterial ecosystem. A better understanding of these mechanisms might ultimately help to define the features of a beneficial enteric microbiota and to develop interventional strategies to overcome adverse microbiota alterations.

肠道菌群对宿主产生重要影响。它促进食物降解，营养吸收，免疫成熟并保护免受病原微生物的感染。但是，某些成分的改变也增加了发生代谢，炎性和免疫介导的疾病的风险。这表明肠微生物群受到强大的进化压力。在这里，我们假设存在内源性，遗传确定的机制，可以塑造和优化肠道菌群。我们讨论了，作为宿主-微生物相互作用起点的产后时期具有最大的机会来确定这种调节机制，并报告了最近发现的两种新方法，即新生儿宿主如何通过某些细菌有利或不利于定殖，从而操纵了出生后出现的细菌生态系统。对这些机制的更好的理解可能最终有助于定义有益的肠道菌群的特征，并开发出克服不利菌群变化的干预策略。