Department of Microbial Ecology, Microbial Ecology - Groningen Institute for Evolutionary Life Sciences, University of Groningen, Nijenborgh 7, Groningen, 9747 AG, The Netherlands.
Sci Rep. 2017 Aug 22;7(1):9156. doi: 10.1038/s41598-017-09317-8.
Bacteriophages constitute key gene transfer agents in many bacteria. Specifically, they may confer gene mobility to Paraburkholderia spp. that dwells in soil and the mycosphere. In this study, we first screened mycosphere and bulk soils for phages able to produce plaques, however found these to be below detection. Then, prophage identification methods were applied to the genome sequences of the mycosphere-derived Paraburkholderia terrae strains BS001, BS007, BS110 and BS437, next to P. phytofirmans strains BS455, BIFAS53, J1U5 and PsJN. These analyses revealed all bacterial genomes to contain considerable amounts [up to 13.3%] of prophage-like sequences. One sequence predicted to encode a complete phage was found in the genome of P. terrae BS437. Using the inducing agent mitomycin C, we produced high-titered phage suspensions. These indeed encompassed the progeny of the identified prophage (denoted ɸ437), as evidenced using phage major capsid gene molecular detection. We obtained the full sequence of phage ɸ437, which, remarkably, had undergone a reshuffling of two large gene blocks. One predicted moron gene was found, and it is currently analyzed to understand the extent of its ecological significance for the host.
噬菌体是许多细菌中重要的基因转移因子。具体来说，它们可能赋予土壤和菌根土壤中栖息的 Paraburkholderia spp. 基因的可移动性。在这项研究中，我们首先筛选了菌根土壤和土壤样本中能够产生噬菌斑的噬菌体，但发现这些噬菌体的数量低于检测限。然后，我们应用原噬菌体鉴定方法对来自菌根土壤的 Paraburkholderia terrae 菌株 BS001、BS007、BS110 和 BS437 以及 P. phytofirmans 菌株 BS455、BIFAS53、J1U5 和 PsJN 的基因组序列进行了分析，结果发现所有细菌基因组都含有大量的原噬菌体样序列（高达 13.3%）。在 P. terrae BS437 的基因组中发现了一个预测编码完整噬菌体的序列。使用诱导剂丝裂霉素 C，我们产生了高滴度的噬菌体悬浮液。这些悬浮液确实包含了鉴定出的原噬菌体（命名为 ɸ437）的后代，这可以通过噬菌体主要衣壳基因的分子检测来证明。我们获得了噬菌体 ɸ437 的完整序列，值得注意的是，它经历了两个大基因块的重排。发现了一个预测的 moron 基因，目前正在对其进行分析，以了解其对宿主的生态意义的程度。
