Laboratory of Veterinary Public Health, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan.
J Appl Microbiol. 2009 Dec 1;107(6):2088-97. doi: 10.1111/j.1365-2672.2009.04431.x. Epub 2009 Jul 15.
To determine phylogenetic groups of clostridia inhabiting the mouse intestine that are essential for normalization of germfree (GF) mice.
Using both the culture method and cloning, clostridia inhabiting the mouse intestine were isolated, and phylogenetic analysis based on 16S rRNA gene sequences was carried out. As a result, the isolates were found to have novel sequences, and no isolate was determined to be identical to previously known identified clostridia. Although the taxonomy of mouse intestinal clostridia was complex, many of them belonged to Clostridium clusters XIVa and IV in conventional (CV) and limited flora mice and ex-germfree mice administered chloroform-treated CV mouse faeces. The clostridia that belonged to cluster XIVa were most often present and showed the highest diversity.
Clostridia belonging clusters XIVa and IV are dominant in the mouse intestine as in other gut ecosystems. The novel groups in these clusters are essential for normalization of GF mice.
The results of this study can be applied in the strict control of mouse intestinal microbiota and will provide important information for normalization of GF mice and also for research on microbiology of the mouse intestine.
确定栖息于无菌（GF）小鼠肠道内的梭菌的进化群，这些梭菌对于 GF 小鼠的正常化是必需的。
使用培养法和克隆法分离栖息于小鼠肠道内的梭菌，并进行基于 16S rRNA 基因序列的系统发育分析。结果发现，这些分离株具有新的序列，并且没有分离株与先前已知的梭菌相同。尽管小鼠肠道梭菌的分类学很复杂，但其中许多属于常规（CV）和有限菌群小鼠以及用氯仿处理的 CV 小鼠粪便处理的无菌前小鼠中的梭菌 XIVa 簇和 IV 簇。属于簇 XIVa 的梭菌最为常见，且多样性最高。
与其他肠道生态系统一样，簇 XIVa 和 IV 的梭菌在小鼠肠道中占主导地位。这些簇中的新群体对于 GF 小鼠的正常化是必需的。
本研究的结果可应用于严格控制小鼠肠道微生物群，并为 GF 小鼠的正常化以及对小鼠肠道微生物学的研究提供重要信息。
