Mimivirus relatives in the Sargasso sea.
Mimivirus relatives in the Sargasso sea.
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DOI：
10.1186/1743-422x-2-62
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发表时间：
2005-08-16
期刊：
影响因子：
4.8
通讯作者：
Claverie, Jean-Michel
中科院分区：
文献类型：
--
作者：
Ghedin, Elodie;Claverie, Jean-Michel
已知的最大的DNA病毒--棘阿米巴多食线虫病毒的发现和基因组分析挑战了许多关于病毒的公认教条。它的颗粒大小(400 Nm)、基因组长度(120万bp)和庞大的基因库(911个蛋白质编码基因)都有助于模糊病毒和最小的寄生细胞生物之间的既定界限。系统发育分析还表明，迷你病毒谱系可能出现在来自三个已建立的领域的细胞生物体个体化之前，引发了一场辩论，只有通过产生和分析更多数据才能解决这一问题。然后，下一步是寻找一些证据，证明米米病毒不是同类病毒的唯一代表，并确定在哪里寻找新的米米病毒科。对所有MimiVirus预测的蛋白质与所有可公开获得的序列进行详尽的相似性搜索后，在马尾藻海环境序列中发现了许多它们最接近的同源物。随后的系统发育分析表明，马尾藻海中大量存在未知的大型病毒，它们在进化上更接近MimiVirus，而不是目前所描述的任何物种。它们的分离和基因组测序对于理解大型DNA病毒的起源和多样性可能被证明是非常宝贵的，并揭示了它们最终在真核生物出现中所起的作用。
The discovery and genome analysis of Acanthamoeba polyphaga Mimivirus, the largest known DNA virus, challenged much of the accepted dogma regarding viruses. Its particle size (>400 nm), genome length (1.2 million bp) and huge gene repertoire (911 protein coding genes) all contribute to blur the established boundaries between viruses and the smallest parasitic cellular organisms. Phylogenetic analyses also suggested that the Mimivirus lineage could have emerged prior to the individualization of cellular organisms from the three established domains, triggering a debate that can only be resolved by generating and analyzing more data. The next step is then to seek some evidence that Mimivirus is not the only representative of its kind and determine where to look for new Mimiviridae. An exhaustive similarity search of all Mimivirus predicted proteins against all publicly available sequences identified many of their closest homologues among the Sargasso Sea environmental sequences. Subsequent phylogenetic analyses suggested that unknown large viruses evolutionarily closer to Mimivirus than to any presently characterized species exist in abundance in the Sargasso Sea. Their isolation and genome sequencing could prove invaluable in understanding the origin and diversity of large DNA viruses, and shed some light on the role they eventually played in the emergence of eukaryotes.