Diversity of dsDNA viruses in a South African hot spring assessed by metagenomics and microscopy

Abstract

The current view of virus diversity in terrestrial hot springs is limited to a few sampling sites. To expand our current understanding of hot spring viral community diversity, this study aimed to investigate the first African hot spring (Brandvlei hot spring; 60 C, pH 5.7) by means of electron microscopy and sequencing of the virus fraction. Microscopy analysis revealed a mixture of regular- and ‘jumbo’-sized tailed morphotypes (Caudovirales), lemon-shaped virions (Fuselloviridae-like; salterprovirus-like) and pleiomorphic virus-like particles. Metavirome analysis corroborated the presence of His1-like viruses and has expanded the current clade of salterproviruses using a polymerase B gene phylogeny. The most represented viral contig was to a cyanophage genome fragment, which may underline basic ecosystem functioning provided by these viruses. Furthermore, a putative Gemmata-related phage was assembled with high coverage, a previously undocumented phage-host association. This study demonstrated that a moderately thermophilic spring environment contained a highly novel pool of viruses and should encourage future characterization of a wider temperature range of hot springs throughout the world.

Description

Keywords

Hot spring, Metavirome, Fuselloviridae, Jumbo phage, Archaeal viruses, Freshwater Cyanophages, Gemmata

Citation

Zablocki, O. et al. (2017). Diversity of dsDNA viruses in a South African hot spring assessed by metagenomics and microscopy. Viruses, 9: 384