Graduate School of Bioresources, Mie University, Tsu, Mie, Japan.
Curr Microbiol. 2010 Feb;60(2):112-6. doi: 10.1007/s00284-009-9513-9. Epub 2009 Sep 29.
The purpose of this study was to detect three fibrolytic bacteria, Fibrobacter succinogenes, Ruminococcus flavefaciens, and Ruminococcus albus, in the cecal digesta of the ostrich (Struthio camelus) by PCR using a species-specific primer set for each 16S ribosomal RNA gene (16S rDNA). Although amplified DNA fragments obtained from each primer set had the expected size, the clone library derived from the amplimer contained non-specific sequences. The F. succinogenes-specific primer set recovered a partial 16S rDNA sequence of an uncultivated Fibrobacter with low similarity (<95%) and distantly related phylogenetic positioning to Fibrobacter sequences deposited in the databases, indicating a novel species of Fibrobacter. The sequence was considered to be identical to a clone detected in our previous experiment. Thus, we confirm that the gastrointestinal tract of the ostrich is one of the habitats of Fibrobacter species. The clone library derived from the R. flavefaciens-specific primer set contained a 16S rDNA sequence with 97% similarity to R. flavefaciens, indicating it could be one of a major fibrolytic bacterium in the ostrich ceca. No R. albus 16S rDNA sequence was found in the clone library of the R. albus-specific primer set.
本研究旨在通过使用针对每个 16S 核糖体 RNA 基因（16S rDNA）的种特异性引物对，从鸵鸟（Struthio camelus）盲肠消化物中检测三种纤维分解菌，即纤维丁酸弧菌、黄色瘤胃球菌和白色瘤胃球菌。虽然从每个引物对获得的扩增 DNA 片段具有预期的大小，但从扩增子获得的克隆文库包含非特异性序列。纤维丁酸弧菌特异性引物对回收了一个与数据库中纤维丁酸弧菌序列相似性低（<95%）且亲缘关系较远的未培养纤维丁酸弧菌的部分 16S rDNA 序列，表明存在一种新型纤维丁酸弧菌。该序列被认为与我们之前实验中检测到的克隆相同。因此，我们确认鸵鸟的胃肠道是纤维丁酸弧菌的栖息地之一。从黄色瘤胃球菌特异性引物对获得的克隆文库包含与黄色瘤胃球菌具有 97%相似性的 16S rDNA 序列，表明它可能是鸵鸟盲肠中主要的纤维分解菌之一。在黄色瘤胃球菌特异性引物对的克隆文库中未发现白色瘤胃球菌 16S rDNA 序列。
