Shandong University, Jinan, PR China.
ISME J. 2010 Dec;4(12):1520-30. doi: 10.1038/ismej.2010.84. Epub 2010 Jul 1.
Microorganisms are globally dispersed and are able to proliferate in any habitat that supports their lifestyles, which, however, has not yet been explored in any specific microbial taxon. The social myxobacteria are considered typical soil bacteria because they have been identified in various terrestrial samples, a few in coastal areas, but none in other oceanic environments. To explore the prevalence of marine myxobacteria and to investigate their phylogenetic relationships with their terrestrial counterparts, we established myxobacteria-enriched libraries of 16S rRNA gene sequences from four deep-sea sediments collected at depths from 853 to 4675 m and a hydrothermal vent at a depth of 204 m. In all, 68 different myxobacteria-related sequences were identified from randomly sequenced clones of the libraries of different samples. These myxobacterial sequences were diverse but phylogenetically similar at different locations and depths. However, they were separated from terrestrial myxobacteria at high levels of classification. This discovery indicates that the marine myxobacteria are phylogeographically separated from their terrestrial relatives, likely because of geographic separation and environment selection.
微生物在全球范围内分散存在，能够在任何支持其生活方式的栖息地中繁殖，然而，这在任何特定的微生物分类群中都尚未得到探索。粘细菌被认为是典型的土壤细菌，因为它们已在各种陆地样本中被识别出来，在一些沿海地区也有发现，但在其他海洋环境中尚未发现。为了探索海洋粘细菌的流行情况，并研究它们与陆地同类的系统发育关系，我们从深度为 853 至 4675 米的四个深海沉积物和深度为 204 米的热液喷口采集了样本，建立了 16S rRNA 基因序列的粘细菌富集文库。总共从不同样本文库的随机测序克隆中鉴定出了 68 种不同的粘细菌相关序列。这些粘细菌序列在不同地点和深度具有多样性，但在系统发育上相似。然而，它们与陆地粘细菌在分类水平上有明显的分离。这一发现表明，海洋粘细菌在地理上与其陆地亲缘种分离，可能是由于地理隔离和环境选择。
