Diversity, distribution, and functional potentials of magroviruses from marine and brackish waters

Bu Xu; Lu Fan; Wenxiu Wang; Yuanqing Zhu; Chuanlun Zhang

doi:10.3389/fmicb.2023.1151034

Diversity, distribution, and functional potentials of magroviruses from marine and brackish waters

Front Microbiol. 2023 Apr 21:14:1151034. doi: 10.3389/fmicb.2023.1151034. eCollection 2023.

Authors

Bu Xu^{1

2}, Lu Fan^{2

3}, Wenxiu Wang², Yuanqing Zhu^{2

4}, Chuanlun Zhang^{2

3

4}

Affiliations

¹ School of Environment, Harbin Institute of Technology, Harbin, China.
² Shenzhen Key Laboratory of Marine Archaea Geo-Omics, Department of Ocean Science and Engineering, Southern University of Science and Technology, Shenzhen, China.
³ Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China.
⁴ Shanghai Sheshan National Geophysical Observatory, Shanghai, China.

Abstract

Marine group II (MGII) archaea (Ca. Poseidoniales) are among the most abundant microbes in global oceanic surface waters and play an important role in driving marine biogeochemical cycles. Magroviruses - the viruses of MGII archaea have been recently found to occur ubiquitously in surface ocean. However, their diversity, distribution, and potential ecological functions in coastal zones especially brackish waters are unknown. Here we obtained 234 non-redundant magroviral genomes from brackish surface waters by using homology searches for viral signature proteins highlighting the uncovered vast diversity of this novel viral group. Phylogenetic analysis based on these brackish magroviruses along with previously reported marine ones identified six taxonomic groups with close evolutionary connection to both haloviruses and the viruses of Marine Group I archaea. Magroviruses were present abundantly both in brackish and open ocean samples with some showing habitat specification and others having broad spectrums of distribution between different habitats. Genome annotation suggests they may be involved in regulating multiple metabolic pathways of MGII archaea. Our results uncover the previously overlooked diversity and ecological potentials of a major archaeal virial group in global ocean and brackish waters and shed light on the cryptic evolutionary history of archaeal viruses.

Keywords: archaeal viruses; brackish water system; magroviruses; marine archaea; marine group II archaea.