Phylogenetic diversity, localization, and cell morphologies of members of the candidate phylum TG3 and a subphylum in the phylum Fibrobacteres, recently discovered bacterial groups dominant in termite guts
Phylogenetic diversity, localization, and cell morphologies of members of the candidate phylum TG3 and a subphylum in the phylum Fibrobacteres, recently discovered bacterial groups dominant in termite guts
复制标题
DOI：
10.1128/aem.00891-06
复制
发表时间：
2006-10-01
影响因子：
4.4
通讯作者：
Ohkuma, Moriya
中科院分区：
文献类型：
--
作者：
Hongoh, Yuichi;Deevong, Pinsurang;Ohkuma, Moriya
最近，我们通过基于pcr的16S rRNA分析，在白蚁肠道中发现了两个新的，深度分支的域细菌谱系（Y. Hongoh， P. Deevong， T. Inoue， S. Moriya， S. Trakulnaleamsai， M. Ohkuma， C. Vongkaluang， N. Noparatnaraporn和T. Kudo, apple）。环绕。微生物学杂志。71:6590-6599,2005)。本文报道了利用荧光原位杂交技术在食木白蚁Microcerotermes sp.和nasuttermes takasagoensis的肠道中特异性检测到这些细菌，即候选门TG3（白蚁组3）和纤维细菌门的一个亚门。这两组细菌几乎只在后肠扩张部分的管腔液中检测到。每种细胞约占原核细胞总数的10%，构成了全肠道微生物群中的第二大优势群。两组检测到的细胞呈波状或振状，明显类似于小螺旋体。TG3和纤维杆菌的细胞大小分别为0.2 ~ 0.4 × 1.3 ~ 6.0 μ m和0.2 ~ 0.3 × 1.3 ~ 4.9 μ m。用特异引物进行PCR筛选，发现这两个类群分布在不同的白蚁中。获得的克隆形成了单系集群，这些集群是由宿主属而不是地理距离划定的，这意味着这些细菌与宿主白蚁之间存在强大的联系。从蟑螂肠道、湖泊沉积物、稻田土壤和深海沉积物中也获得了TG3无性系。我们的研究结果表明，TG3和纤维杆菌是各种白蚁的原生肠道共生体，TG3成员也广泛分布在各种其他环境中。
Recently we discovered two novel, deeply branching lineages in the domain Bacteria from termite guts by PCR-based analyses of 16S rRNA (Y. Hongoh, P. Deevong, T. Inoue, S. Moriya, S. Trakulnaleamsai, M. Ohkuma, C. Vongkaluang, N. Noparatnaraporn, and T. Kudo, Appl. Environ. Microbiol. 71:6590-6599, 2005). Here, we report on the specific detection of these bacteria, the candidate phylum TG3 (Termite Group 3) and a subphylum in the phylum Fibrobacteres, by fluorescence in situ hybridization in the guts of the wood-feeding termites Microcerotermes sp. and Nasutitermes takasagoensis. Both bacterial groups were detected almost exclusively from the luminal fluid of the dilated portion in the hindgut. Each accounted for approximately 10% of the total prokaryotic cells, constituting the second-most dominant groups in the whole-gut microbiota. The detected cells of both groups were in undulate or vibroid forms and apparently resembled small spirochetes. The cell sizes were 0.2 to 0.4 by 1.3 to 6.0 mu m and 0.2 to 0.3 by 1.3 to 4.9 mu m in the TG3 and Fibrobacteres, respectively. Using PCR screenings with specific primers, we found that both groups are distributed among various termites. The obtained clones formed monophyletic clusters that were delineated by the host genus rather than by the geographic distance, implying a robust association between these bacteria and host termites. TG3 clones were also obtained from a cockroach gut, lake sediment, rice paddy soil, and deep-sea sediments. Our results suggest that the TG3 and Fibrobacteres bacteria are autochthonous gut symbionts of various termites and that the TG3 members are also widely distributed among various other environments.