Rapid diversification of coevolving marine Synechococcus and a virus
Rapid diversification of coevolving marine Synechococcus and a virus
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DOI：
10.1073/pnas.1120310109
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发表时间：
2012-03-20
影响因子：
11.1
通讯作者：
Martiny, Jennifer B. H.
中科院分区：
文献类型：
--
作者：
Marston, Marcia F.;Pierciey, Francis J., Jr.;Martiny, Jennifer B. H.
海洋病毒对其宿主细菌造成很高的死亡率，而同时海洋细菌的病毒抵抗力似乎很高。对抗性共同进化——相互作用物种的相互进化变化——如果能够导致快速且动态的病毒抵抗力，那么它可能会调和这些观察结果。在这里，我们展示了生态上重要的海洋蓝细菌聚球藻和裂解病毒之间广泛的拮抗共同进化的潜力。在一项为期 6 个月的重复恒化器实验中，聚球藻属 sp。 WH7803和病毒（RIM8）经历了多个共同进化周期，导致宿主和病毒迅速多样化。在实验过程中，我们在每个恒化器中检测到 4 到 13 个新进化的病毒表型（宿主范围不同）和 4 到 11 个新进化的聚球藻表型（病毒抗性不同）。对分离株的基因组分析确定了宿主和病毒中可能影响它们相互作用的几个候选基因。值得注意的是，所有候选病毒都不是尾部纤维基因，而尾部纤维基因被认为是有尾噬菌体宿主范围的主要决定因素，这凸显了概括噬菌体感染变形菌结果的困难。最后，我们表明，成对的病毒-宿主共同进化可能会产生更广泛的社区后果；恒化器中的共同进化改变了聚球藻对多种病毒的敏感性，以及病毒感染其他聚球藻菌株的能力。我们的结果表明，快速共同进化可能有助于聚球藻和病毒多样性的产生和维持，从而影响这些关键海洋细菌的病毒介导的死亡率。
Marine viruses impose a heavy mortality on their host bacteria, whereas at the same time the degree of viral resistance in marine bacteria appears to be high. Antagonistic coevolution-the reciprocal evolutionary change of interacting species-might reconcile these observations, if it leads to rapid and dynamic levels of viral resistance. Here we demonstrate the potential for extensive antagonistic coevolution between the ecologically important marine cyanobacterium Synechococcus and a lytic virus. In a 6-mo-long replicated chemostat experiment, Synechococcus sp. WH7803 and the virus (RIM8) underwent multiple coevolutionary cycles, leading to the rapid diversification of both host and virus. Over the course of the experiment, we detected between 4 and 13 newly evolved viral phenotypes (differing in host range) and between 4 and 11 newly evolved Synechococcus phenotypes (differing in viral resistance) in each chemostat. Genomic analysis of isolates identified several candidate genes in both the host and virus that might influence their interactions. Notably, none of the viral candidates were tail fiber genes, thought to be the primary determinants of host range in tailed bacteriophages, highlighting the difficulty in generalizing results from bacteriophage infecting.-Proteobacteria. Finally, we show that pairwise virus-host coevolution may have broader community consequences; coevolution in the chemostat altered the sensitivity of Synechoccocus to a diverse suite of viruses, as well as the virus' ability to infect additional Synechococcus strains. Our results indicate that rapid coevolution may contribute to the generation and maintenance of Synechococcus and virus diversity and thereby influence viral-mediated mortality of these key marine bacteria.