Department of Integrative Biology University of Texas, Austin, United States.
Elife. 2020 Feb 26;9:e51599. doi: 10.7554/eLife.51599.
Gokushoviruses are single-stranded, circular DNA bacteriophages found in metagenomic datasets from diverse ecosystems worldwide, including human gut microbiomes. Despite their ubiquity and abundance, little is known about their biology or host range: Isolates are exceedingly rare, known only from three obligate intracellular bacterial genera. By synthesizing circularized phage genomes from prophages embedded in diverse enteric bacteria, we produced gokushoviruses in an experimentally tractable model system, allowing us to investigate their features and biology. We demonstrate that virions can reliably infect and lysogenize hosts by hijacking a conserved chromosome-dimer resolution system. Sequence motifs required for lysogeny are detectable in other metagenomically defined gokushoviruses; however, we show that even partial motifs enable phages to persist cytoplasmically without leading to collapse of their host culture. This ability to employ multiple, disparate survival strategies is likely key to the long-term persistence and global distribution of .
Gokushoviruses 是单链、环形 DNA 噬菌体，在来自全球各种生态系统的宏基因组数据集（包括人类肠道微生物组）中被发现。尽管它们无处不在且丰富，但人们对其生物学或宿主范围知之甚少：分离株极为罕见，仅从三个专性细胞内细菌属中得知。通过从不同肠细菌中的潜伏噬菌体基因组合成环形化的噬菌体基因组，我们在一个实验上易于处理的模型系统中产生了 gokushoviruses，从而能够研究它们的特征和生物学。我们证明，通过劫持保守的染色体二聚体分辨率系统，病毒颗粒可以可靠地感染和溶原化宿主。在其他通过宏基因组定义的 gokushoviruses 中可以检测到用于溶原性的序列基序；然而，我们表明，即使是部分基序也能使噬菌体在细胞质中持续存在，而不会导致其宿主培养物崩溃。这种能够采用多种不同的生存策略的能力可能是 长期存在和全球分布的关键。
