Evolution of satellite plasmids can prolong the maintenance of newly acquired accessory genes in bacteria
Evolution of satellite plasmids can prolong the maintenance of newly acquired accessory genes in bacteria
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DOI：
10.1038/s41467-019-13709-x
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发表时间：
2019-12
影响因子：
16.6
通讯作者：
Xue Zhang;Daniel E. Deatherage;Hao Zheng;Stratton J. Georgoulis;Jeffrey E. Barrick
中科院分区：
文献类型：
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作者：
Xue Zhang;Daniel E. Deatherage;Hao Zheng;Stratton J. Georgoulis;Jeffrey E. Barrick
可传播质粒将编码抗生素抗性和其他特性的基因传播给新的细菌物种。在这里，我们报告说，实验室人口ofEscherichia coli与新获得的IncQ质粒往往演变的“卫星质粒”与删除的辅助基因和基因所需的质粒复制。卫星质粒是分子寄生物：它们的存在减少了它们继续复制所依赖的全长质粒的拷贝数。具有卫星质粒的细胞通过减少辅助基因的繁重表达而获得直接的适应性优势。然而，它们保留了这些基因的拷贝和完整的质粒，这可能使它们能够在未来受益于并传播它们编码的性状。卫星质粒的进化是短暂的。从长远来看，完全失去辅助基因功能或质粒移动性的细胞占主导地位。卫星质粒也进化inSassgrassella alvicolonizing蜜蜂肠道，这表明这种机制可能广泛有助于IncQ质粒的重要性，在自然界中的细菌基因转移的代理。
Transmissible plasmids spread genes encoding antibiotic resistance and other traits to new bacterial species. Here we report that laboratory populations ofEscherichia coliwith a newly acquired IncQ plasmid often evolve ‘satellite plasmids’ with deletions of accessory genes and genes required for plasmid replication. Satellite plasmids are molecular parasites: their presence reduces the copy number of the full-length plasmid on which they rely for their continued replication. Cells with satellite plasmids gain an immediate fitness advantage from reducing burdensome expression of accessory genes. Yet, they maintain copies of these genes and the complete plasmid, which potentially enables them to benefit from and transmit the traits they encode in the future. Evolution of satellite plasmids is transient. Cells that entirely lose accessory gene function or plasmid mobility dominate in the long run. Satellite plasmids also evolve inSnodgrassella alvicolonizing the honey bee gut, suggesting that this mechanism may broadly contribute to the importance of IncQ plasmids as agents of bacterial gene transfer in nature.