The 3Cs provide a novel concept of bacterial species: messages from the genome as illustrated by Salmonella
The 3Cs provide a novel concept of bacterial species: messages from the genome as illustrated by Salmonella
复制标题
DOI：
10.1007/s10482-011-9680-0
复制
发表时间：
2012-01-01
影响因子：
2.6
通讯作者：
Liu, Shu-Lin
中科院分区：
文献类型：
--
作者：
Tang, Le;Liu, Shu-Lin
困扰细菌分类学和系统学的一个关键问题是缺乏生物物种定义。用于在遗传和生物学基础上定义细菌种类的标准应该能够揭示细菌群之间的明确界限。迄今为止，DNA-DNA重关联测定和核糖体RNA序列比较在确定细菌之间的相对进化距离方面很有用，但这些数据是连续的，因此不能将细菌簇定义为分类单位，称为物种。以沙门氏菌为模型，我们寻找了细菌群的明确的遗传和生物学独特性。根据我们的发现，每个沙门氏菌谱系都有一个独特的基因组结构，同一谱系的菌株共享，但不与其他沙门氏菌谱系的菌株重叠，我们得出结论，这是细菌分化后遗传分离的结果。我们建议在基因组水平上，不同种类的细菌之间应该存在遗传边界，这需要进一步的基因组信息来验证。
A key issue troubling bacterial taxonomy and systematics is the lack of a biological species definition. Criteria to be used for defining bacterial species on genetic and biological bases should be able to reveal clear-cut boundaries among clusters of bacteria. To date, DNA-DNA re-association assays and ribosomal RNA sequence comparison have been useful in determining relative evolutionary distances among bacteria but the data are continuous and thus cannot define bacterial clusters as taxonomic units to be called species. Using Salmonella as models, we have looked for definite genetic and biologic uniqueness of clusters of bacteria. Based on our findings that each Salmonella lineage has a unique genome structure shared by strains of the same lineage but not overlapping with strains of other Salmonella lineages, we conclude that this is a result of genetic isolation following divergence of the bacteria. We propose that there should be genetic boundaries between different species of bacteria at the genomic level, which awaits further genomic information for validation.