Despite their herbivorous lifestyle, studies have shown that the panda faecal microbiota is more similar to other Carnivora than to unrelated SN-38 herbivores suggesting that next to diet also gut physiology is a regulator of the faecal microbiota composition [13, 35]. Within the Firmicutes, the majority of the Clostridiales isolates common to both clone libraries
was assigned to Clostridium clusters XIVa (43%), XI (38%) and I (13%). Our results are consistent with previous studies that reported a high prevalence of these three Clostridium clusters in carnivores [48, 49]. Likewise, similar distributions were found in feline microbiome studies using 16S rRNA clone libraries [43, 50] or 16S rRNA gene pyrosequencing [42]. Also in the two cheetahs studied by Ley and co-workers [35], similar high abundances of Clostridium clusters XIVa and XI were found in two other cheetahs. Clostridium cluster Sapitinib concentration XIVa constitutes a major and highly diverse bacterial group in the distal intestines of mammals [51]. This phylogenetically heterogeneous cluster is
in both clone libraries represented by Ruminococcaceae spp. most closely related to known mucin-degrading organisms such as Ruminococcus torques and Ruminococcus gnavus[52] as well as members of the recently proposed genus Blautia[53]. The latter group comprises important producers selleck inhibitor of short-chain fatty acids such as butyrate, which is an important source of energy for colonic epithelial cells and has shown to possess anti-inflammatory and anticarcinogenic potential [54, 55]. Feline and canine inflammatory bowel diseases have been associated with reduced bacterial species richness and a reduced proportion of Clostridium cluster XIVa [56–58]. Noteworthy, the two cheetahs included in our study showed no signs of gastrointestinal disease. Clostridium clusters XI and I include saccharolytic fibre-fermenting species but also proteolytic or toxinogenic clostridia [34]. In Clostridium cluster XI, 87% of the common sequences displayed >99% sequence similarity to the type strain of Clostridium hiranonis. This species was PDK4 first described in human faeces and
displays bile acid 7-α-dehydroxylating activity. In addition, acetic acid and minor amounts of propionic acid and iso-butyric acid are produced from mono- and disaccharides [59]. Ritchie and co-workers [43] found Clostridium cluster XI to account for 22% of the faecal microbiota in healthy cats. Up to 86% of the clones assigned to Clostridium cluster I in our study were phylogenetically most closely related to the type strain of the potentially pathogenic species Clostridium perfringens. However, with reported isolation rates of up to 63% in healthy cats [60], C. perfringens should probably be considered as a common commensal of the feline intestine. Moreover, no significant differences in prevalence of either C.