Schierack Peter, Walk Nicole, Reiter Katja, Weyrauch Karl D, Wieler Lothar H
Institut für Mikrobiologie und Tierseuchen, Freie Universität Berlin, Philippstr. 13, 10115 Berlin, Germany.
Institut für Veterinär-Anatomie, Freie Universität Berlin, Koserstr. 20, 14195 Berlin, Germany.
Microbiology (Reading). 2007 Nov;153(Pt 11):3830-3837. doi: 10.1099/mic.0.2007/010173-0.
In this study, the Enterobacteriaceae microbiota, including their diversity as well as the distribution of haemolytic and virulence gene-harbouring Escherichia coli of 56-day-old healthy piglets, was characterized. Both the composition and the diversity of Enterobacteriaceae populations varied considerably between individual pigs and intestinal sections. E. coli, Enterobacter cloacae, Citrobacter freundii and Klebsiella pneumoniae dominated the Enterobacteriaceae microbiota. However, mucosa-associated Enterobacteriaceae were scarce or in some cases undetectable. The majority of E. coli clones from the jejunum were also found in the colon, with up to 10 different E. coli clones in one intestinal section. Other Enterobacteriaceae species were represented by only one clone localized to one intestinal section. While several piglets did not harbour virulence gene-positive or haemolytic E. coli, such strains dominated intestinal sections of other animals. This study reveals that the diversity of intestinal Enterobacteriaceae is clearly individual. In general, Enterobacteriaceae do not appear to be a consistent fraction of the microbiota of the jejunum. High numbers of adherent bacteria do not appear to be essential for successful intestinal colonization, and E. coli clones do not necessarily colonize distinct intestinal sections based on the particular phylogenetic affiliation. Furthermore, dominance of haemolytic or virulence gene-positive E. coli does not correlate with disease. Finally, probiotic Enterococcus faecium feed supplementation does not affect the Enterobacteriaceae microbiota.
在本研究中，对56日龄健康仔猪的肠杆菌科微生物群进行了特征分析，包括其多样性以及携带溶血和毒力基因的大肠杆菌的分布情况。肠杆菌科菌群的组成和多样性在个体猪和肠道节段之间差异很大。大肠杆菌、阴沟肠杆菌、弗氏柠檬酸杆菌和肺炎克雷伯菌在肠杆菌科微生物群中占主导地位。然而，与黏膜相关的肠杆菌科细菌很少，在某些情况下甚至无法检测到。来自空肠的大多数大肠杆菌克隆也在结肠中被发现，在一个肠道节段中最多有10种不同的大肠杆菌克隆。其他肠杆菌科物种仅由定位于一个肠道节段的一个克隆代表。虽然几只仔猪未携带毒力基因阳性或溶血大肠杆菌，但此类菌株在其他动物的肠道节段中占主导地位。本研究表明，肠道肠杆菌科的多样性明显具有个体差异。一般来说，肠杆菌科似乎不是空肠微生物群的一个稳定组成部分。大量的黏附细菌对于成功的肠道定植似乎并非必不可少，并且大肠杆菌克隆不一定基于特定的系统发育关系而定植于不同的肠道节段。此外，溶血或毒力基因阳性大肠杆菌的优势地位与疾病无关。最后，补充益生菌粪肠球菌饲料不会影响肠杆菌科微生物群。
