Biogeographic Variation in Host Range Phenotypes and Taxonomic Composition of Marine Cyanophage Isolates.
Biogeographic Variation in Host Range Phenotypes and Taxonomic Composition of Marine Cyanophage Isolates.
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DOI：
10.3389/fmicb.2016.00983
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发表时间：
2016
影响因子：
5.2
通讯作者：
Martiny JB
中科院分区：
文献类型：
--
作者：
Hanson CA;Marston MF;Martiny JB
尽管生物多样性在海洋系统中发挥着重要作用，但人们对其多样性在空间中的分布情况知之甚少。海洋生物的生物地理模式可能很难检测，由于其巨大的遗传多样性，这可能无法准确地代表保守的标记基因。为了研究海洋蓝藻的空间地理结构，我们在美国三个沿海地区（罗得岛、华盛顿和南加州）的聚球藻宿主菌株WH 7803上分离出400多个噬藻体。大约90%的噬藻体分离物是肌病毒，而另外10%是足病毒。分离物的多样性进一步以两种方式表征：（i）分类学上，使用保守的标记基因;和（ii）表型上，通过测试分离物感染一套宿主或其“宿主范围”的能力。由于宿主范围是一个高度可变的性状，即使在密切相关的菌株，我们假设，宿主范围的噬藻体分离株的表型会更强烈的不同地点之间的分类组成。相反，我们发现的证据都在分类组成和主机范围表型，与三个沿海地区之间的分类重叠很小的地理变化。对于分类组成和宿主范围表型，噬藻体社区从加州和罗得岛是最不相似的，而华盛顿社区表现出相似性的其他两个位置。这些结果表明，宿主动态的空间变异所施加的选择影响噬藻体的地理分布。
Despite the important role of phages in marine systems, little is understood about how their diversity is distributed in space. Biogeographic patterns of marine phages may be difficult to detect due to their vast genetic diversity, which may not be accurately represented by conserved marker genes. To investigate the spatial biogeographic structure of marine phages, we isolated over 400 cyanophages on Synechococcus host strain WH7803 at three coastal locations in the United States (Rhode Island, Washington, and southern California). Approximately 90% of the cyanophage isolates were myoviruses, while the other 10% were podoviruses. The diversity of isolates was further characterized in two ways: (i) taxonomically, using conserved marker genes and (ii) phenotypically, by testing isolates for their ability to infect a suite of hosts, or their “host range.” Because host range is a highly variable trait even among closely related isolates, we hypothesized that host range phenotypes of cyanophage isolates would vary more strongly among locations than would taxonomic composition. Instead, we found evidence for strong biogeographic variation both in taxonomic composition and host range phenotypes, with little taxonomic overlap among the three coastal regions. For both taxonomic composition and host range phenotypes, cyanophage communities from California and Rhode Island were the most dissimilar, while Washington communities exhibited similarity to each of the other two locations. These results suggest that selection imposed by spatial variation in host dynamics influence the biogeographic distribution of cyanophages.