Molecular Evolution and Systematics of Animals, Institute of Biology, University of Leipzig, Talstrasse 33, 04103 Leipzig, Germany.
Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany.
Nat Commun. 2014 Oct 6;5:5117. doi: 10.1038/ncomms6117.
Of all obligate intracellular bacteria, Wolbachia is probably the most common. In general, Wolbachia are either widespread, opportunistic reproductive parasites of arthropods or essential mutualists in a single group of filarial nematodes, including many species of medical significance. To date, a robust phylogenetic backbone of Wolbachia is lacking and consequently, many Wolbachia-related phenomena cannot be discussed in a broader evolutionary context. Here we present the first comprehensive phylogenomic analysis of Wolbachia supergroup relationships based on new whole-genome-shotgun data. Our results suggest that Wolbachia has switched between its two major host groups at least twice. The ability of some arthropod-infecting Wolbachia to universally infect and to adapt to a broad range of hosts quickly is restricted to a single monophyletic lineage (containing supergroups A and B). Thus, the currently observable pandemic has likely a single evolutionary origin and is unique within the radiation of Wolbachia strains.
在所有专性细胞内细菌中，沃尔巴克氏体可能是最常见的。一般来说，沃尔巴克氏体要么是广泛存在的、机会主义的节肢动物生殖寄生虫，要么是包括许多具有医学意义的物种在内的单一组丝虫的必要共生体。迄今为止，沃尔巴克氏体缺乏强大的系统发育骨干，因此，许多与沃尔巴克氏体相关的现象无法在更广泛的进化背景下进行讨论。在这里，我们基于新的全基因组鸟枪法数据，首次对沃尔巴克氏体超级群的关系进行了全面的基因组系统发育分析。我们的研究结果表明，沃尔巴克氏体至少在两种主要宿主群之间发生了两次切换。一些感染节肢动物的沃尔巴克氏体普遍感染和快速适应广泛宿主的能力仅限于一个单系谱系（包含超级群 A 和 B）。因此，目前观察到的大流行可能只有一个单一的进化起源，并且在沃尔巴克氏体菌株的辐射中是独一无二的。
