Heterogeneous Viral Strategies Promote Coexistence in Virus-Microbe Systems
Heterogeneous Viral Strategies Promote Coexistence in Virus-Microbe Systems
复制标题
异质病毒策略促进病毒-微生物系统共存
DOI：
10.1101/297127
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
J. Weitz
中科院分区：
文献类型：
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作者：
H. Gulbudak;J. Weitz
微生物病毒，包括细菌病毒（噬菌体）、古菌病毒和真核病毒，可以影响单个微生物和整个种群的命运。在这里，我们模拟了病毒与宿主相互作用的不同模式，并研究了它们对病毒及其微生物宿主的丰度和多样性的影响。我们考虑两种不同的病毒群体通过两种不同的策略感染相同的微生物群体：裂解和慢性。裂解策略对应于专门感染并裂解宿主以释放新病毒粒子的病毒。慢性策略对应于感染宿主的病毒，然后通过出芽过程不断释放新病毒而无需细胞裂解。慢性病毒也可以在细胞分裂过程中传递给子细胞。病毒和微生物在慢性模式下的长期关联导致了相对于裂解模式的选择压力的差异。我们利用相应的非线性微分方程模型的入侵分析来研究异质病毒策略的生态和进化。我们首先研究平衡的稳定性，并表征一些参数区域的振荡和双稳态动力学。然后，我们得出两种病毒类型的适应量，并研究竞争排斥和共存的条件。通过这样做，我们发现了意想不到的结果，包括慢性病毒需要裂解病毒才能生存和入侵的机制。
Viruses of microbes, including bacterial viruses (phage), archaeal viruses, and eukaryotic viruses, can influence the fate of individual microbes and entire populations. Here, we model distinct modes of virus-host interactions and study their impact on the abundance and diversity of both viruses and their microbial hosts. We consider two distinct viral populations infecting the same microbial population via two different strategies: lytic and chronic. A lytic strategy corresponds to viruses that exclusively infect and lyse their hosts to release new virions. A chronic strategy corresponds to viruses that infect hosts and then continually release new viruses via a budding process without cell lysis. The chronic virus can also be passed on to daughter cells during cell division. The long-term association of virus and microbe in the chronic mode drives differences in selective pressures with respect to the lytic mode. We utilize invasion analysis of the corresponding nonlinear differential equation model to study the ecology and evolution of heterogenous viral strategies. We first investigate stability of equilibria, and characterize oscillatory and bistable dynamics in some parameter regions. Then, we derive fitness quantities for both virus types and investigate conditions for competitive exclusion and coexistence. In so doing we find unexpected results, including a regime in which the chronic virus requires the lytic virus for survival and invasion.