PDF(Pubmed)
Abstract：
Plasmids are so closely associated with pathogens and antibiotic resistance that their potential for conferring other traits is often overlooked. Few studies consider how the full suite of traits encoded by plasmids is related to a host\'s environmental adaptation, particularly for Gram-positive bacteria. To investigate the role that plasmid traits might play in microbial communities from natural ecosystems, we identified plasmids carried by isolates of Curtobacterium (phylum Actinomycetota) from a variety of soil environments. We found that plasmids were common, but not ubiquitous, in the genus and varied greatly in their size and genetic diversity. There was little evidence of phylogenetic conservation among Curtobacterium plasmids even for closely related bacterial strains within the same ecotype, indicating that horizontal transmission of plasmids is common. The plasmids carried a wide diversity of traits that were not a random subset of the host chromosome. Furthermore, the composition of these plasmid traits was associated with the environmental context of the host bacterium. Together, the results indicate that plasmids contribute substantially to the microdiversity of a soil bacterium and that this diversity may play a role in niche differentiation and a bacterium\'s adaptation to its local environment.
摘要：
质粒与病原体和抗生素抗性密切相关，以至于它们赋予其他性状的潜力经常被忽视。很少有研究考虑质粒编码的全套性状与宿主的环境适应有关，特别是革兰氏阳性细菌。为了研究质粒性状在自然生态系统微生物群落中可能发挥的作用，我们从各种土壤环境中鉴定了由弯曲杆菌（放线菌门）分离物携带的质粒。我们发现质粒很常见,但不是无处不在，在属中，其大小和遗传多样性差异很大。即使是同一生态型中密切相关的细菌菌株，也几乎没有证据表明弯曲杆菌质粒之间的系统发育保守性，表明质粒的水平传输是常见的。质粒具有广泛的性状多样性，这些性状不是宿主染色体的随机子集。此外，这些质粒性状的组成与宿主细菌的环境相关。一起,结果表明，质粒对土壤细菌的微多样性有很大贡献，这种多样性可能在生态位分化和细菌对其局部环境的适应中起作用。
