Malki Kema, Kula Alex, Bruder Katherine, Sible Emily, Hatzopoulos Thomas, Steidel Stephanie, Watkins Siobhan C, Putonti Catherine
Department of Biology, Loyola University Chicago, Chicago, IL, 60660, USA.
Bioinformatics Program, Loyola University Chicago, Chicago, IL, 60660, USA.
Virol J. 2015 Oct 9;12:164. doi: 10.1186/s12985-015-0395-0.
The study of bacteriophages continues to generate key information about microbial interactions in the environment. Many phenotypic characteristics of bacteriophages cannot be examined by sequencing alone, further highlighting the necessity for isolation and examination of phages from environmental samples. While much of our current knowledge base has been generated by the study of marine phages, freshwater viruses are understudied in comparison. Our group has previously conducted metagenomics-based studies samples collected from Lake Michigan - the data presented in this study relate to four phages that were extracted from the same samples.
Four phages were extracted from Lake Michigan on the same bacterial host, exhibiting similar morphological characteristics as shown under transmission electron microscopy. Growth characteristics of the phages were unique to each isolate. Each phage demonstrated a host-range spanning several phyla of bacteria - to date, such a broad host-range is yet to be reported. Genomic data reveals genomes of a similar size, and close similarities between the Lake Michigan phages and the Pseudomonas phage PB1, however, the majority of annotated genes present were ORFans and little insight was offered into mechanisms for host-range.
The phages isolated from Lake Michigan are capable of infecting several bacterial phyla, and demonstrate varied phenotypic characteristics despite similarities in host preference, and at the genomic level. We propose that such a broad host-range is likely related to the oligotrophic nature of Lake Michigan, and the competitive benefit that this characteristic may lend to phages in nature.
噬菌体研究持续产生有关环境中微生物相互作用的关键信息。许多噬菌体的表型特征无法仅通过测序来检测，这进一步凸显了从环境样本中分离和检测噬菌体的必要性。虽然我们目前的许多知识库是通过对海洋噬菌体的研究产生的，但相比之下，淡水病毒的研究较少。我们团队此前对从密歇根湖采集的样本进行了基于宏基因组学的研究——本研究中呈现的数据涉及从相同样本中提取的四种噬菌体。
从密歇根湖的同一细菌宿主中提取了四种噬菌体，在透射电子显微镜下显示出相似的形态特征。每种噬菌体分离株的生长特性都是独特的。每种噬菌体都表现出跨越几个细菌门的宿主范围——迄今为止，如此广泛的宿主范围尚未见报道。基因组数据显示基因组大小相似，且密歇根湖噬菌体与假单胞菌噬菌体PB1之间有密切的相似性，然而，大多数注释基因都是孤儿基因，对宿主范围的机制了解甚少。
从密歇根湖分离出的噬菌体能够感染几个细菌门，并且尽管在宿主偏好和基因组水平上有相似之处，但表现出不同的表型特征。我们认为，如此广泛的宿主范围可能与密歇根湖的贫营养性质以及这一特征可能赋予噬菌体在自然环境中的竞争优势有关。
