Phages actively challenge niche communities in Antarctic soils

• Published in: mSystems
• Main Authors: Bezuidt, Keoagile Ignatius Oliver, Lebre, Pedro H., Pierneef, Rian Ewald, Leon-Sobrino, Carlos, Adriaenssens, Evelien M., Cowan, Don A., Van de Peer, Yves, Makhalanyane, Thulani P.
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Society for Microbiology 2020
• Subjects: Antarctic soils; Archaea; Bacteria; Hypoliths; Phages; Viromics; Antarc*; Antarctic
• Online Access: http://hdl.handle.net/2263/79991; https://doi.org/10.1128/mSystems.00234-20

By modulating the structure, diversity, and trophic outputs of microbial communities, phages play crucial roles in many biomes. In oligotrophic polar deserts, the effects of katabatic winds, constrained nutrients, and low water availability are known to limit microbial activity. Although phages may substantially govern trophic interactions in cold deserts, relatively little is known regarding the precise ecological mechanisms. Here, we provide the first evidence of widespread antiphage innate immunity in Antarctic environments using metagenomic sequence data from hypolith communities as model systems. In particular, immunity systems such as DISARM and BREX are shown to be dominant systems in these communities. Additionally, we show a direct correlation between the CRISPR-Cas adaptive immunity and the metavirome of hypolith communities, suggesting the existence of dynamic host-phage interactions. In addition to providing the first exploration of immune systems in cold deserts, our results suggest that phages actively challenge niche communities in Antarctic polar deserts. We provide evidence suggesting that the regulatory role played by phages in this system is an important determinant of bacterial host interactions in this environment. The National Research Foundation (NRF), the South African National Antarctic Program (SANAP 110717), the University of Pretoria, the Fulbright Visiting Scholar Program and the Biotechnology and Biological Sciences Research Council (BBSRC). https://msystems.asm.org am2021 Biochemistry Genetics Microbiology and Plant Pathology