Host-virus interactions structure microbial communities, drive biogeochemical cycles and enhance genetic diversity in nature1,2. Hypotheses proposed to explain the range of interactions that mediate these processes often invoke lysogeny3-6, a latent infection strategy used by temperate bacterial viruses to replicate in host cells until an induction event triggers the production and lytic release of free viruses. Most cultured bacteria harbour temperate viruses in their genomes (prophage)7. The absence of prophages in cultures of the dominant lineages of marine bacteria has contributed to an ongoing debate over the ecological significance of lysogeny and other viral life strategies in nature6,8-15. Here, we report the discovery of prophages in cultured SAR11, the ocean's most abundant clade of heterotrophic bacteria16,17. We show the concurrent production of cells and viruses, with enhanced virus production under carbon-limiting growth conditions. Evidence that related prophages are broadly distributed in the oceans suggests that similar interactions have contributed to the evolutionary success of SAR11 in nutrient-limited systems.

中文翻译：

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SAR11 海洋细菌中的溶原性宿主病毒相互作用。


宿主-病毒相互作用构建微生物群落，驱动生物地球化学循环并增强自然界的遗传多样性1,2。为解释介导这些过程的相互作用范围而提出的假设通常会调用溶原性3-6，这是温带细菌病毒使用的一种潜伏感染策略，用于在宿主细胞中复制，直到诱导事件触发游离病毒的产生和裂解释放。大多数培养细菌的基因组中都含有温带病毒（原噬菌体）7。海洋细菌主要谱系培养物中缺乏原噬菌体，引发了关于溶源和自然界其他病毒生命策略的生态意义的持续争论6,8-15。在这里，我们报告了在培养的 SAR11 中发现了原噬菌体，SAR11 是海洋中最丰富的异养细菌分支 16,17。我们展示了细胞和病毒的同时产生，并且在碳限制生长条件下病毒产量增强。相关原噬菌体广泛分布在海洋中的证据表明，类似的相互作用有助于 SAR11 在营养有限的系统中进化成功。