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George NA, Zhou Z, Anantharaman K, Hug LA. Discarded diversity: Novel megaphages, auxiliary metabolic genes, and virally encoded CRISPR-Cas systems in landfills. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.30.596742. [PMID: 38854013 PMCID: PMC11160803 DOI: 10.1101/2024.05.30.596742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Background Viruses are the most abundant microbial entity on the planet, impacting microbial community structure and ecosystem services. Despite outnumbering Bacteria and Archaea by an order of magnitude, viruses have been comparatively underrepresented in reference databases. Metagenomic examinations have illustrated that viruses of Bacteria and Archaea have been specifically understudied in engineered environments. Here we employed metagenomic and computational biology methods to examine the diversity, host interactions, and genetic systems of viruses predicted from 27 samples taken from three municipal landfills across North America. Results We identified numerous viruses that are not represented in reference databases, including the third largest bacteriophage genome identified to date (~678 kbp), and note a cosmopolitan diversity of viruses in landfills that are distinct from viromes in other systems. Host-virus interactions were examined via host CRISPR spacer to viral protospacer mapping which captured hyper-targeted viral populations and six viral populations predicted to infect across multiple phyla. Virally-encoded auxiliary metabolic genes (AMGs) were identified with the potential to augment hosts' methane, sulfur, and contaminant degradation metabolisms, including AMGs not previously reported in literature. CRISPR arrays and CRISPR-Cas systems were identified from predicted viral genomes, including the two largest bacteriophage genomes to contain these genetic features. Some virally encoded Cas effector proteins appear distinct relative to previously reported Cas systems and are interesting targets for potential genome editing tools. Conclusions Our observations indicate landfills, as heterogeneous contaminated sites with unique selective pressures, are key locations for diverse viruses and atypical virus-host dynamics.
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Affiliation(s)
- Nikhil A. George
- Department of Biology, University of Waterloo, Waterloo ON, Canada
| | - Zhichao Zhou
- Department of Bacteriology, University of Wisconsin – Madison, Madison, WI, USA
| | | | - Laura A. Hug
- Department of Biology, University of Waterloo, Waterloo ON, Canada
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Liu Y, Meng X, Zheng H, Cai L, Wei S, He M, He J, Hao Y, Ge C, Liu J, Chen F, Xu Y. A novel long-tailed myovirus represents a new T4-like cyanophage cluster. Front Microbiol 2023; 14:1293846. [PMID: 38029084 PMCID: PMC10665884 DOI: 10.3389/fmicb.2023.1293846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 10/19/2023] [Indexed: 12/01/2023] Open
Abstract
Cyanophages affect the abundance, diversity, metabolism, and evolution of picocyanobacteria in marine ecosystems. Here we report an estuarine Synechococcus phage, S-CREM2, which represents a novel viral genus and leads to the establishment of a new T4-like cyanophage clade named cluster C. S-CREM2 possesses the longest tail (~418 nm) among isolated cyanomyoviruses and encodes six tail-related proteins that are exclusively homologous to those predicted in the cluster C cyanophages. Furthermore, S-CREM2 may carry three regulatory proteins in the virion, which may play a crucial role in optimizing the host intracellular environment for viral replication at the initial stage of infection. The cluster C cyanophages lack auxiliary metabolic genes (AMGs) that are commonly found in cyanophages of the T4-like clusters A and B and encode unique AMGs like an S-type phycobilin lyase gene. A variation in the composition of tRNA and cis-regulatory RNA genes was observed between the marine and freshwater phage strains in cluster C, reflecting their different modes of coping with hosts and habitats. The cluster C cyanophages are widespread in estuarine and coastal regions and exhibit equivalent or even higher relative abundance compared to those of clusters A and B cyanophages in certain estuarine regions. The isolation of cyanophage S-CREM2 provides new insights into the phage-host interactions mediated by both newly discovered AMGs and virion-associated proteins and emphasizes the ecological significance of cluster C cyanophages in estuarine environments.
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Affiliation(s)
- Yuanfang Liu
- Institute of Marine Science and Technology, Shandong University, Qingdao, China
| | - Xue Meng
- Institute of Marine Science and Technology, Shandong University, Qingdao, China
| | - Hongrui Zheng
- Institute of Marine Science and Technology, Shandong University, Qingdao, China
| | - Lanlan Cai
- Department of Ocean Science, The Hong Kong University of Science and Technology, Kowloon, Hong Kong SAR, China
| | - Shuzhen Wei
- State Key Laboratory of Marine Environmental Science, Fujian Key Laboratory of Marine Carbon Sequestration, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Minglu He
- School of Information Science and Engineering, Shandong University, Qingdao, China
| | - Jiale He
- School of Life Science, Shandong University, Qingdao, China
| | - Yue Hao
- School of Life Science, Shandong University, Qingdao, China
| | - Chang Ge
- School of Life Science, Shandong University, Qingdao, China
| | - Jihua Liu
- Institute of Marine Science and Technology, Shandong University, Qingdao, China
| | - Feng Chen
- Institute of Marine and Environmental Technology, University of Maryland Center for Environmental Science, Baltimore, MD, United States
| | - Yongle Xu
- Institute of Marine Science and Technology, Shandong University, Qingdao, China
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Cai L, Liu H, Zhang W, Xiao S, Zeng Q, Dang S. Cryo-EM structure of cyanophage P-SCSP1u offers insights into DNA gating and evolution of T7-like viruses. Nat Commun 2023; 14:6438. [PMID: 37833330 PMCID: PMC10575957 DOI: 10.1038/s41467-023-42258-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 10/05/2023] [Indexed: 10/15/2023] Open
Abstract
Cyanophages, together with their host cyanobacteria, play important roles in marine biogeochemical cycles and control of marine food webs. The recently identified MPP-C (Marine Picocyanobacteria Podovirus clade C) cyanophages, belonging to the T7-like podoviruses, contain the smallest genomes among cyanopodoviruses and exhibit distinct infection kinetics. However, understanding of the MPP-C cyanophage infection process is hindered by the lack of high-resolution structural information. Here, we report the cryo-EM structure of the cyanophage P-SCSP1u, a representative member of the MPP-C phages, in its native form at near-atomic resolution, which reveals the assembly mechanism of the capsid and molecular interaction of the portal-tail complex. Structural comparison of the capsid proteins of P-SCSP1u and other podoviruses with known structures provides insights into the evolution of T7-like viruses. Furthermore, our study provides the near-atomic resolution structure of portal-tail complex for T7-like viruses. On the basis of previously reported structures of phage T7, we identify an additional valve and gate to explain the DNA gating mechanism for the T7-like viruses.
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Affiliation(s)
- Lanlan Cai
- Department of Ocean Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
- HKUST Shenzhen-Hong Kong Collaborative Innovation Research Institute, Shenzhen, China
| | - Hang Liu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Wen Zhang
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Shiwei Xiao
- Department of Ocean Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Qinglu Zeng
- Department of Ocean Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
- HKUST Shenzhen-Hong Kong Collaborative Innovation Research Institute, Shenzhen, China.
- Center for Ocean Research in Hong Kong and Macau, The Hong Kong University of Science and Technology, Hong Kong, China.
| | - Shangyu Dang
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
- HKUST-Shenzhen Research Institute, Nanshan, Shenzhen 518057, China.
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4
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Wang T, Luo L, Xiong Y, Wang C, Shao H, Wang M, Guo C. Characterization and genomic analysis of an oceanic cyanophage infecting marine Synechococcus reveal a novel genus. Front Microbiol 2023; 14:1231279. [PMID: 37601358 PMCID: PMC10436341 DOI: 10.3389/fmicb.2023.1231279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 07/25/2023] [Indexed: 08/22/2023] Open
Abstract
Cyanophages play a crucial role in the biogeochemical cycles of aquatic ecosystems by affecting the population dynamics and community structure of cyanobacteria. In this study, a novel cyanophage, Nanhaivirus ms29, that infects Synechococcus sp. MW02 was isolated from the ocean basin in the South China Sea. It was identified as a T4-like phage using transmission electron microscopy. Phylogenetic analysis demonstrated that this cyanophage is distinct from other known T4-like cyanophage, belonging to a novel genus named Nanhaivirus within the family Kyanoviridae, according to the most recent classification proposed by the International Committee on Taxonomy of Viruses (ICTV). The genome of this novel cyanophage is composed of 178,866 bp of double-stranded DNA with a G + C content of 42.5%. It contains 217 potential open reading frames (ORFs) and 6 tRNAs. As many as 30 auxiliary metabolic genes (AMGs) were identified in the genome, which related to photosynthesis, carbon metabolism, nutrient uptake and stress tolerance, possibly reflecting a genomic adaption to the oligotrophic environment. Read-mapping analysis showed that Nanhaivirus ms29 mainly distributed in temperate and tropical epipelagic waters. This study enriches of the virus gene database of cyanophages and provides valuable insights into the phylogeny of cyanophages and their interactions with their hosts.
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Affiliation(s)
- Tiancong Wang
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, China
| | - Lin Luo
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, China
| | - Yao Xiong
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, China
| | - Chuxiao Wang
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, China
| | - Hongbing Shao
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, China
- UMT-OUC Joint Centre for Marine Studies, Ocean University of China, Qingdao, China
| | - Min Wang
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, China
- UMT-OUC Joint Centre for Marine Studies, Ocean University of China, Qingdao, China
- Haide College, Ocean University of China, Qingdao, China
- The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Cui Guo
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, China
- UMT-OUC Joint Centre for Marine Studies, Ocean University of China, Qingdao, China
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Wang Y, Ferrinho S, Connaris H, Goss RJM. The Impact of Viral Infection on the Chemistries of the Earth's Most Abundant Photosynthesizes: Metabolically Talented Aquatic Cyanobacteria. Biomolecules 2023; 13:1218. [PMID: 37627283 PMCID: PMC10452541 DOI: 10.3390/biom13081218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 07/17/2023] [Accepted: 07/24/2023] [Indexed: 08/27/2023] Open
Abstract
Cyanobacteria are the most abundant photosynthesizers on earth, and as such, they play a central role in marine metabolite generation, ocean nutrient cycling, and the control of planetary oxygen generation. Cyanobacteriophage infection exerts control on all of these critical processes of the planet, with the phage-ported homologs of genes linked to photosynthesis, catabolism, and secondary metabolism (marine metabolite generation). Here, we analyze the 153 fully sequenced cyanophages from the National Center for Biotechnology Information (NCBI) database and the 45 auxiliary metabolic genes (AMGs) that they deliver into their hosts. Most of these AMGs are homologs of those found within cyanobacteria and play a key role in cyanobacterial metabolism-encoding proteins involved in photosynthesis, central carbon metabolism, phosphate metabolism, methylation, and cellular regulation. A greater understanding of cyanobacteriophage infection will pave the way to a better understanding of carbon fixation and nutrient cycling, as well as provide new tools for synthetic biology and alternative approaches for the use of cyanobacteria in biotechnology and sustainable manufacturing.
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Affiliation(s)
- Yunpeng Wang
- School of Chemistry, University of St Andrews, North Haugh, St Andrews KY16 9AJ, UK; (S.F.); (H.C.)
- Biomedical Sciences Research Complex, University of St Andrews, North Haugh, St Andrews KY16 9SX, UK
| | - Scarlet Ferrinho
- School of Chemistry, University of St Andrews, North Haugh, St Andrews KY16 9AJ, UK; (S.F.); (H.C.)
- Biomedical Sciences Research Complex, University of St Andrews, North Haugh, St Andrews KY16 9SX, UK
| | - Helen Connaris
- School of Chemistry, University of St Andrews, North Haugh, St Andrews KY16 9AJ, UK; (S.F.); (H.C.)
- Biomedical Sciences Research Complex, University of St Andrews, North Haugh, St Andrews KY16 9SX, UK
| | - Rebecca J. M. Goss
- School of Chemistry, University of St Andrews, North Haugh, St Andrews KY16 9AJ, UK; (S.F.); (H.C.)
- Biomedical Sciences Research Complex, University of St Andrews, North Haugh, St Andrews KY16 9SX, UK
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6
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Luo L, Ma X, Guo R, Jiang T, Wang T, Shao H, He H, Wang H, Liang Y, McMinn A, Guo C, Wang M. Characterization and genomic analysis of a novel Synechococcus phage S-H9-2 belonging to Bristolvirus genus isolated from the Yellow Sea. Virus Res 2023; 328:199072. [PMID: 36781075 DOI: 10.1016/j.virusres.2023.199072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 02/08/2023] [Accepted: 02/10/2023] [Indexed: 02/15/2023]
Abstract
Cyanophages are known to influence the population dynamics and community structure of cyanobacteria and thus play an important role in biogeochemical cycles in aquatic ecosystems. In this study, a novel Synechococcus phage S-H9-2 infecting Synechococcus sp. WH 8102 was isolated from the coastal water of the Yellow Sea. Synechococcus phage S-H9-2 contains a 187,320 bp genome of double-stranded DNA with a G + C content of 40.3%, 202 potential open reading frames (ORFs), and 15 tRNAs. Phylogenetic analysis and nucleotide-based intergenomic similarity suggest that Synechococcus phage S-H9-2 belongs to the Bristolvirus genus under the family Kyanoviridae. Homologs of the S-H9-2 open reading frame can be found in a variety of marine environments, as shown by the results of mapping the genome sequence of S-H9-2 to the Global Ocean Viromes 2.0 dataset. The presence of auxiliary metabolic genes (AMGs) related to photosynthesis, carbon metabolism, and phosphorus assimilation, as well as phylogenetic relationships based on complete genome sequences, reflect the mechanism of phage-host interaction and host-specific strategies for adaptation to environmental conditions. This study enriches the current genomic database of cyanophage and contributed to our understanding of the virus-host interactions and their adaption to the environment.
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Affiliation(s)
- Lin Luo
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
| | - Xiaohong Ma
- Department of Pediatrics, Qingdao Municipal Hospital, Qingdao266011, China
| | - Ruizhe Guo
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
| | - Tong Jiang
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
| | - Tiancong Wang
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
| | - Hongbing Shao
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China; UMT-OUC Joint Centre for Marine Studies, Qingdao 266003, China
| | - Hui He
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China; UMT-OUC Joint Centre for Marine Studies, Qingdao 266003, China
| | - Hualong Wang
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China; UMT-OUC Joint Centre for Marine Studies, Qingdao 266003, China
| | - Yantao Liang
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China; UMT-OUC Joint Centre for Marine Studies, Qingdao 266003, China
| | - Andrew McMinn
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China; Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, TAS 7001, SA
| | - Cui Guo
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China; UMT-OUC Joint Centre for Marine Studies, Qingdao 266003, China.
| | - Min Wang
- College of Marine Life Sciences, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China; UMT-OUC Joint Centre for Marine Studies, Qingdao 266003, China; The Affiliated Hospital of Qingdao University, Qingdao 266000, China.
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7
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George NA, Hug LA. CRISPR-resolved virus-host interactions in a municipal landfill include non-specific viruses, hyper-targeted viral populations, and interviral conflicts. Sci Rep 2023; 13:5611. [PMID: 37019939 PMCID: PMC10076291 DOI: 10.1038/s41598-023-32078-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 03/22/2023] [Indexed: 04/07/2023] Open
Abstract
Viruses are the most abundant microbial guild on the planet, impacting microbial community structure and ecosystem services. Viruses are specifically understudied in engineered environments, including examinations of their host interactions. We examined host-virus interactions via host CRISPR spacer to viral protospacer mapping in a municipal landfill across two years. Viruses comprised ~ 4% of both the unassembled reads and assembled basepairs. A total of 458 unique virus-host connections captured hyper-targeted viral populations and host CRISPR array adaptation over time. Four viruses were predicted to infect across multiple phyla, suggesting that some viruses are far less host-specific than is currently understood. We detected 161 viral elements that encode CRISPR arrays, including one with 187 spacers, the longest virally-encoded CRISPR array described to date. Virally-encoded CRISPR arrays targeted other viral elements in interviral conflicts. CRISPR-encoding proviruses integrated into host chromosomes were latent examples of CRISPR-immunity-based superinfection exclusion. The bulk of the observed virus-host interactions fit the one-virus-one-host paradigm, but with limited geographic specificity. Our networks highlight rare and previously undescribed complex interactions influencing the ecology of this dynamic engineered system. Our observations indicate landfills, as heterogeneous contaminated sites with unique selective pressures, are key locations for atypical virus-host dynamics.
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Affiliation(s)
- Nikhil A George
- Department of Biology, University of Waterloo, Waterloo, ON, Canada
| | - Laura A Hug
- Department of Biology, University of Waterloo, Waterloo, ON, Canada.
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Rodríguez-Ramos J, Oliverio A, Borton MA, Danczak R, Mueller BM, Schulz H, Ellenbogen J, Flynn RM, Daly RA, Schopflin L, Shaffer M, Goldman A, Lewandowski J, Stegen JC, Wrighton KC. Spatial and temporal metagenomics of river compartments reveals viral community dynamics in an urban impacted stream. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.04.535500. [PMID: 37066413 PMCID: PMC10104031 DOI: 10.1101/2023.04.04.535500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
Although river ecosystems comprise less than 1% of Earth's total non-glaciated area, they are critical modulators of microbially and virally orchestrated global biogeochemical cycles. However, most studies either use data that is not spatially resolved or is collected at timepoints that do not reflect the short life cycles of microorganisms. As a result, the relevance of microbiome interactions and the impacts they have over time on biogeochemical cycles are poorly understood. To assess how viral and microbial communities change over time, we sampled surface water and pore water compartments of the wastewater-impacted River Erpe in Germany every 3 hours over a 48-hour period resulting in 32 metagenomes paired to geochemical and metabolite measurements. We reconstructed 6,500 viral and 1,033 microbial genomes and found distinct communities associated with each river compartment. We show that 17% of our vMAGs clustered to viruses from other ecosystems like wastewater treatment plants and rivers. Our results also indicated that 70% of the viral community was persistent in surface waters, whereas only 13% were persistent in the pore waters taken from the hyporheic zone. Finally, we predicted linkages between 73 viral genomes and 38 microbial genomes. These putatively linked hosts included members of the Competibacteraceae, which we suggest are potential contributors to carbon and nitrogen cycling. Together, these findings demonstrate that microbial and viral communities in surface waters of this urban river can exist as stable communities along a flowing river; and raise important considerations for ecosystem models attempting to constrain dynamics of river biogeochemical cycles.
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Cai L, Xu B, Li H, Xu Y, Wei W, Zhang R. Spatiotemporal Shift of T4-Like Phage Community Structure in the Three Largest Estuaries of China. Microbiol Spectr 2023; 11:e0520322. [PMID: 36877016 PMCID: PMC10101079 DOI: 10.1128/spectrum.05203-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Accepted: 02/08/2023] [Indexed: 03/07/2023] Open
Abstract
Estuaries are one of the most highly productive and economically important ecosystems at the continent-ocean interface. Estuary productivity is largely determined by the microbial community structure and activity. Viruses are major agents of microbial mortality and are key drivers of global geochemical cycles. However, the taxonomic diversity of viral communities and their spatial-temporal distribution in estuarine ecosystems have been poorly studied. In this study, we investigated the T4-like viral community composition at three major Chinese estuaries in winter and in summer. Diverse T4-like viruses, which were divided into three main clusters (Clusters I to III), were revealed. The Marine Group of Cluster III, with seven identified subgroups, was the most dominant (averaging 76.5% of the total sequences) in the Chinese estuarine ecosystems. Significant variations of T4-like viral community composition were observed among estuaries and seasons, with higher diversity occurring in winter. Among various environmental variables, temperature was a main driver of the viral communities. This study demonstrates viral assemblage diversification and seasonality in Chinese estuarine ecosystems. IMPORTANCE Viruses are ubiquitous but largely uncharacterized members of aquatic environments that cause significant mortality in microbial communities. Recent large-scale oceanic projects have greatly advanced our understanding of viral ecology in marine environments, but those studies mostly focused on oceanic regions. There have yet to be spatiotemporal studies of viral communities in estuarine ecosystems, which are unique habitats that play a significant role in global ecology and biogeochemistry. This work is the first comprehensive study that provides a detailed picture of the spatial and seasonal variation of viral communities (specifically, T4-like viral communities) in three major estuarine ecosystems in China. These findings provide much-needed knowledge regarding estuarine viral ecosystems, which currently lags in oceanic ecosystem research.
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Affiliation(s)
- Lanlan Cai
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
- Department of Ocean Science, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Bu Xu
- School of Environment, Harbin Institute of Technology, Harbin, China
- Department of Ocean Science and Engineering, Southern University of Science and Technology, Shenzhen, China
| | - Huifang Li
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
- Key Laboratory of Coastal Salt Marsh Ecosystems and Resources, Ministry of Natural Resources, Jiangsu Ocean University, Lianyungang, China
| | - Yongle Xu
- Institute of Marine Science and Technology, Shandong University, Shandong, China
| | - Wei Wei
- School of Environmental Ecology and Biological Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Rui Zhang
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
- Institute for Advanced Study, Shenzhen University, Shenzhen, China
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10
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Fuchsman CA, Garcia Prieto D, Hays MD, Cram JA. Associations between picocyanobacterial ecotypes and cyanophage host genes across ocean basins and depth. PeerJ 2023; 11:e14924. [PMID: 36874978 PMCID: PMC9983427 DOI: 10.7717/peerj.14924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 01/30/2023] [Indexed: 03/06/2023] Open
Abstract
Background Cyanophages, viruses that infect cyanobacteria, are globally abundant in the ocean's euphotic zone and are a potentially important cause of mortality for marine picocyanobacteria. Viral host genes are thought to increase viral fitness by either increasing numbers of genes for synthesizing nucleotides for virus replication, or by mitigating direct stresses imposed by the environment. The encoding of host genes in viral genomes through horizontal gene transfer is a form of evolution that links viruses, hosts, and the environment. We previously examined depth profiles of the proportion of cyanophage containing various host genes in the Eastern Tropical North Pacific Oxygen Deficient Zone (ODZ) and at the subtropical North Atlantic (BATS). However, cyanophage host genes have not been previously examined in environmental depth profiles across the oceans. Methodology We examined geographical and depth distributions of picocyanobacterial ecotypes, cyanophage, and their viral-host genes across ocean basins including the North Atlantic, Mediterranean Sea, North Pacific, South Pacific, and Eastern Tropical North and South Pacific ODZs using phylogenetic metagenomic read placement. We determined the proportion of myo and podo-cyanophage containing a range of host genes by comparing to cyanophage single copy core gene terminase (terL). With this large dataset (22 stations), network analysis identified statistical links between 12 of the 14 cyanophage host genes examined here with their picocyanobacteria host ecotypes. Results Picyanobacterial ecotypes, and the composition and proportion of cyanophage host genes, shifted dramatically and predictably with depth. For most of the cyanophage host genes examined here, we found that the composition of host ecotypes predicted the proportion of viral host genes harbored by the cyanophage community. Terminase is too conserved to illuminate the myo-cyanophage community structure. Cyanophage cobS was present in almost all myo-cyanophage and did not vary in proportion with depth. We used the composition of cobS phylotypes to track changes in myo-cyanophage composition. Conclusions Picocyanobacteria ecotypes shift with changes in light, temperature, and oxygen and many common cyanophage host genes shift concomitantly. However, cyanophage phosphate transporter gene pstS appeared to instead vary with ocean basin and was most abundant in low phosphate regions. Abundances of cyanophage host genes related to nutrient acquisition may diverge from host ecotype constraints as the same host can live in varying nutrient concentrations. Myo-cyanophage community in the anoxic ODZ had reduced diversity. By comparison to the oxic ocean, we can see which cyanophage host genes are especially abundant (nirA, nirC, and purS) or not abundant (myo psbA) in ODZs, highlighting both the stability of conditions in the ODZ and the importance of nitrite as an N source to ODZ endemic LLV Prochlorococcus.
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Affiliation(s)
- Clara A Fuchsman
- Horn Point Laboratory, University of Maryland Center for Environmental Science, Cambridge, MD, United States of America
| | - David Garcia Prieto
- Horn Point Laboratory, University of Maryland Center for Environmental Science, Cambridge, MD, United States of America
| | - Matthew D Hays
- Horn Point Laboratory, University of Maryland Center for Environmental Science, Cambridge, MD, United States of America
| | - Jacob A Cram
- Horn Point Laboratory, University of Maryland Center for Environmental Science, Cambridge, MD, United States of America
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Two Novel Yersinia pestis Bacteriophages with a Broad Host Range: Potential as Biocontrol Agents in Plague Natural Foci. Viruses 2022; 14:v14122740. [PMID: 36560744 PMCID: PMC9785759 DOI: 10.3390/v14122740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 12/02/2022] [Accepted: 12/05/2022] [Indexed: 12/13/2022] Open
Abstract
Bacteriophages (phages) have been successfully used as disinfectors to kill bacteria in food and the environment and have been used medically for curing human diseases. The objective of this research was to elucidate the morphological and genomic characteristics of two novel Yersinia pestis phages, vB_YpeM_ MHS112 (MHS112) and vB_YpeM_GMS130 (GMS130), belonging to the genus Gaprivervirus, subfamily Tevenvirinae, family Myoviridae. Genome sequencing showed that the sizes of MHS112 and GMS130 were 170507 and 168552 bp, respectively. A total of 303 and 292 open reading frames with 2 tRNA and 3 tRNA were predicted in MHS112 and GMS130, respectively. The phylogenetic relationships were analysed among the two novel Y. pestis phages, phages in the genus Gaprivervirus, and several T4-like phages infecting the Yersinia genus. The bacteriophage MHS112 and GMS130 exhibited a wider lytic host spectrum and exhibited comparative temperature and pH stability. Such features signify that these phages do not need to rely on Y. pestis as their host bacteria in the ecological environment, while they could be based on more massive Enterobacteriales species to propagate and form ecological barriers against Y. pestis pathogens colonised in plague foci. Such characteristics indicated that the two phages have potential as biocontrol agents for eliminating the endemics of animal plague in natural plague foci.
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Baran N, Carlson MCG, Sabehi G, Peleg M, Kondratyeva K, Pekarski I, Lindell D. Widespread yet persistent low abundance of TIM5-like cyanophages in the oceans. Environ Microbiol 2022; 24:6476-6492. [PMID: 36116015 PMCID: PMC10087341 DOI: 10.1111/1462-2920.16210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 09/12/2022] [Indexed: 01/12/2023]
Abstract
Ocean ecosystems are inhabited by a diverse set of viruses that impact microbial mortality and evolution. However, the distribution and abundances of specific viral lineages, particularly those from the large bank of rare viruses, remains largely unknown. Here, we assessed the diversity and abundance of the TIM5-like cyanophages. The sequencing of three new TIM5-like cyanophage genomes and environmental amplicons of a signature gene from the Red Sea revealed highly conserved gene content and sequence similarity. We adapted the polony method, a solid-phase polymerase chain reaction assay, to quantify TIM5-like cyanophages during three 2000 km expeditions in the Pacific Ocean and four annual cycles in the Red Sea. TIM5-like cyanophages were widespread, detected at all latitudes and seasons surveyed throughout the photic zone. Yet they were generally rare, ranging between <100 and 4000 viruses·ml-1 . Occasional peaks in abundance of 10- to 100-fold were observed, reaching 71,000 viruses·ml-1 . These peaks were ephemeral and seasonally variable in the Red Sea. Infection levels, quantified during one such peak, were very low. These characteristics of low diversity and abundance, as well as variable outbreaks, distinguishes the TIM5-like lineage from other major cyanophage lineages and illuminates that rare virus lineages can be persistent and widespread in the oceans.
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Affiliation(s)
- Nava Baran
- Technion - Israel Institute of Technology, Faculty of Biology, Haifa, Israel
| | - Michael C G Carlson
- Technion - Israel Institute of Technology, Faculty of Biology, Haifa, Israel
| | - Gazalah Sabehi
- Technion - Israel Institute of Technology, Faculty of Biology, Haifa, Israel
| | - Margalit Peleg
- Technion - Israel Institute of Technology, Faculty of Biology, Haifa, Israel
| | - Kira Kondratyeva
- Technion - Israel Institute of Technology, Faculty of Biology, Haifa, Israel
| | - Irena Pekarski
- Technion - Israel Institute of Technology, Faculty of Biology, Haifa, Israel
| | - Debbie Lindell
- Technion - Israel Institute of Technology, Faculty of Biology, Haifa, Israel
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13
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Wang Q, Cai L, Zhang R, Wei S, Li F, Liu Y, Xu Y. A Unique Set of Auxiliary Metabolic Genes Found in an Isolated Cyanophage Sheds New Light on Marine Phage-Host Interactions. Microbiol Spectr 2022; 10:e0236722. [PMID: 36190421 PMCID: PMC9602691 DOI: 10.1128/spectrum.02367-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 09/10/2022] [Indexed: 01/04/2023] Open
Abstract
Cyanophages, viruses that infect cyanobacteria, are abundant and widely distributed in aquatic ecosystems, playing important roles in regulating the abundance, activity, diversity, and evolution of cyanobacteria. A T4-like cyanophage, S-SCSM1, infecting Synechococcus and Prochlorococcus strains of different ecotypes, was isolated from the South China Sea in this study. For the first time, a mannose-6-phosphate isomerase (MPI) gene was identified in the cultured cyanophage. At least 11 phylogenetic clusters of cyanophage MPIs were retrieved and identified from the marine metagenomic data sets, indicating that cyanophage MPIs in the marine environment are extremely diverse. The existence of 24 genes encoding 2-oxoglutarate (2OG)-Fe(II) oxygenase superfamily proteins in the S-SCSM1 genome emphasizes their potential importance and diverse functions in reprogramming host metabolism during phage infection. Novel cell wall synthesis and modification genes found in the S-SCSM1 genome indicate that diverse phenotypic modifications imposed by phages on cyanobacterial hosts remain to be discovered. Two noncoding RNAs of cis-regulatory elements in the S-SCSM1 genome were predicted to be associated with host exopolysaccharide metabolism and photosynthesis. The isolation and genomic characterization of cyanophage S-SCSM1 provide more information on the genetic diversity of cyanophages and phage-host interactions in the marine environment. IMPORTANCE Cyanophages play important ecological roles in aquatic ecosystems. Genomic and proteomic characterizations of the T4-like cyanophage S-SCSM1 indicate that novel and diverse viral genes and phage-host interactions in the marine environment remain unexplored. The first identified mannose-6-phosphate isomerase (MPI) gene from a cultured cyanophage was found in the S-SCSM1 genome, although MPIs were previously found in viral metagenomes at high frequencies similar to those of the cyanophage photosynthetic gene psbA. The presence of 24 genes encoding 2-oxoglutarate (2OG)-Fe(II) oxygenase superfamily proteins, novel cell wall synthesis and modification genes, a nonbleaching protein A gene, and 2 noncoding RNAs of cis-regulatory elements in the S-SCSM1 genome as well as the presence of a virion-associated regulatory protein indicate the diverse functions that cyanophages have in reprogramming the metabolism and modifying the phenotypes of hosts during infection.
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Affiliation(s)
- Qiong Wang
- Institute of Marine Science and Technology, Shandong University, Qingdao, People’s Republic of China
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen, People’s Republic of China
| | - Lanlan Cai
- Department of Ocean Science, The Hong Kong University of Science and Technology, Hong Kong, People’s Republic of China
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, People’s Republic of China
| | - Rui Zhang
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen, People’s Republic of China
| | - Shuzhen Wei
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Fujian Key Laboratory of Marine Carbon Sequestration, Xiamen University, Xiamen, People’s Republic of China
| | - Fang Li
- State Key Laboratory Breeding Base of Marine Genetic Resource, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, People’s Republic of China
| | - Yuanfang Liu
- Institute of Marine Science and Technology, Shandong University, Qingdao, People’s Republic of China
| | - Yongle Xu
- Institute of Marine Science and Technology, Shandong University, Qingdao, People’s Republic of China
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Genomes from Uncultivated Pelagiphages Reveal Multiple Phylogenetic Clades Exhibiting Extensive Auxiliary Metabolic Genes and Cross-Family Multigene Transfers. mSystems 2022; 7:e0152221. [PMID: 35972150 PMCID: PMC9599517 DOI: 10.1128/msystems.01522-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
For the abundant marine Alphaproteobacterium Pelagibacter (SAR11), and other bacteria, phages are powerful forces of mortality. However, little is known about the most abundant Pelagiphages in nature, such as the widespread HTVC023P-type, which is currently represented by two cultured phages. Using viral metagenomic data sets and fluorescence-activated cell sorting, we recovered 80 complete, undescribed Podoviridae genomes that form 10 phylogenomically distinct clades (herein, named Clades I to X) related to the HTVC023P-type. These expanded the HTVC023P-type pan-genome by 15-fold and revealed 41 previously unknown auxiliary metabolic genes (AMGs) in this viral lineage. Numerous instances of partner-AMGs (colocated and involved in related functions) were observed, including partners in nucleotide metabolism, DNA hypermodification, and Curli biogenesis. The Type VIII secretion system (T8SS) responsible for Curli biogenesis was identified in nine genomes and expanded the repertoire of T8SS proteins reported thus far in viruses. Additionally, the identified T8SS gene cluster contained an iron-dependent regulator (FecR), as well as a histidine kinase and adenylate cyclase that can be implicated in T8SS function but are not within T8SS operons in bacteria. While T8SS are lacking in known Pelagibacter, they contribute to aggregation and biofilm formation in other bacteria. Phylogenetic reconstructions of partner-AMGs indicate derivation from cellular lineages with a more recent transfer between viral families. For example, homologs of all T8SS genes are present in syntenic regions of distant Myoviridae Pelagiphages, and they appear to have alphaproteobacterial origins with a later transfer between viral families. The results point to an unprecedented multipartner-AMG transfer between marine Myoviridae and Podoviridae. Together with the expansion of known metabolic functions, our studies provide new prospects for understanding the ecology and evolution of marine phages and their hosts. IMPORTANCE One of the most abundant and diverse marine bacterial groups is Pelagibacter. Phages have roles in shaping Pelagibacter ecology; however, several Pelagiphage lineages are represented by only a few genomes. This paucity of data from even the most widespread lineages has imposed limits on the understanding of the diversity of Pelagiphages and their impacts on hosts. Here, we report 80 complete genomes, assembled directly from environmental data, which are from undescribed Pelagiphages and render new insights into the manipulation of host metabolism during infection. Notably, the viruses have functionally related partner genes that appear to be transferred between distant viruses, including a suite that encode a secretion system which both brings a new functional capability to the host and is abundant in phages across the ocean. Together, these functions have important implications for phage evolution and for how Pelagiphage infection influences host biology in manners extending beyond canonical viral lysis and mortality.
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A Novel Freshwater Cyanophage Mae-Yong1326-1 Infecting Bloom-Forming Cyanobacterium Microcystis aeruginosa. Viruses 2022; 14:v14092051. [PMID: 36146857 PMCID: PMC9503304 DOI: 10.3390/v14092051] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 09/02/2022] [Accepted: 09/13/2022] [Indexed: 11/25/2022] Open
Abstract
Microcystis aeruginosa is a major harmful cyanobacterium causing water bloom worldwide. Cyanophage has been proposed as a promising tool for cyanobacterial bloom. In this study, M. aeruginosa FACHB-1326 was used as an indicator host to isolate cyanophage from Lake Taihu. The isolated Microcystis cyanophage Mae-Yong1326-1 has an elliptical head of about 47 nm in diameter and a slender flexible tail of about 340 nm in length. Mae-Yong1326-1 could lyse cyanobacterial strains across three orders (Chroococcales, Nostocales, and Oscillatoriales) in the host range experiments. Mae-Yong1326-1 was stable in stability tests, maintaining high titers at 0–40 °C and at a wide pH range of 3–12. Mae-Yong 1326-1 has a burst size of 329 PFU/cell, which is much larger than the reported Microcystis cyanophages so far. The complete genome of Mae-Yong1326-1 is a double-stranded DNA of 48, 822 bp, with a G + C content of 71.80% and long direct terminal repeats (DTR) of 366 bp, containing 57 predicted ORFs. No Mae-Yong1326-1 ORF was found to be associated with virulence factor or antibiotic resistance. PASC scanning illustrated that the highest nucleotide sequence similarity between Mae-Yong1326-1 and all known phages in databases was only 17.75%, less than 70% (the threshold to define a genus), which indicates that Mae-Yong1326-1 belongs to an unknown new genus. In the proteomic tree based on genome-wide sequence similarities, Mae-Yong1326-1 distantly clusters with three unclassified Microcystis cyanophages (MinS1, Mwe-Yong1112-1, and Mwes-Yong2). These four Microcystis cyanophages form a monophyletic clade, which separates at a node from the other clade formed by two independent families (Zierdtviridae and Orlajensenviridae) of Caudoviricetes class. We propose to establish a new family to harbor the Microcystis cyanophages Mae-Yong1326-1, MinS1, Mwe-Yong1112-1, and Mwes-Yong2. This study enriched the understanding of freshwater cyanophages.
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Abstract
Alteromonas is an opportunistic marine bacterium that persists in the global ocean and has important ecological significance. However, current knowledge about the diversity and ecology of alterophages (phages that infect Alteromonas) is lacking. Here, three similar phages infecting Alteromonas macleodii ATCC 27126T were isolated and physiologically characterized. Transmission electron microscopy revealed Siphoviridae morphology, with an oblate icosahedral head and a long noncontractile tail. Notably, these members displayed a small burst size (15–19 plaque-forming units/cell) yet an extensively broad host spectrum when tested on 175 Alteromonas strains. Such unique infection kinetics are potentially associated with discrepancies in codon usage bias from the host tRNA inventory. Phylogenetic analysis indicated that the three phages are closely evolutionarily related; they clustered at the species level and represent a novel genus. Three auxiliary metabolic genes with roles in nucleotide metabolism and putative biofilm dispersal were found in these phage genomes, which revealed important biogeochemical significance of these alterophages in marine ecosystems. Our isolation and characterization of these novel phages expand the current understanding of alterophage diversity, evolution, and phage–host interactions. IMPORTANCE The marine bacterium Alteromonas is prevalent in the global ocean with crucial ecological significance; however, little is known about the diversity and evolution of its bacteriophages that profoundly affect the bacterial communities. Our study characterized a novel genus of three newly isolated Alteromonas phages that exhibited a distinct infection strategy of broad host spectrum and small burst size. This strategy is likely a consequence of the viral trade-off between virulence and lysis profiles during phage–host coevolution, and our work provides new insight into viral evolution and infection strategies.
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17
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Heyerhoff B, Engelen B, Bunse C. Auxiliary Metabolic Gene Functions in Pelagic and Benthic Viruses of the Baltic Sea. Front Microbiol 2022; 13:863620. [PMID: 35875520 PMCID: PMC9301287 DOI: 10.3389/fmicb.2022.863620] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 06/02/2022] [Indexed: 11/13/2022] Open
Abstract
Marine microbial communities are facing various ecosystem fluctuations (e.g., temperature, organic matter concentration, salinity, or redox regimes) and thus have to be highly adaptive. This might be supported by the acquisition of auxiliary metabolic genes (AMGs) originating from virus infections. Marine bacteriophages frequently contain AMGs, which allow them to augment their host’s metabolism or enhance virus fitness. These genes encode proteins for the same metabolic functions as their highly similar host homologs. In the present study, we analyzed the diversity, distribution, and composition of marine viruses, focusing on AMGs to identify their putative ecologic role. We analyzed viruses and assemblies of 212 publicly available metagenomes obtained from sediment and water samples across the Baltic Sea. In general, the virus composition in both compartments differed compositionally. While the predominant viral lifestyle was found to be lytic, lysogeny was more prevalent in sediments than in the pelagic samples. The highest proportion of AMGs was identified in the genomes of Myoviridae. Overall, the most abundantly occurring AMGs are encoded for functions that protect viruses from degradation by their hosts, such as methylases. Additionally, some detected AMGs are known to be involved in photosynthesis, 7-cyano-7-deazaguanine synthesis, and cobalamin biosynthesis among other functions. Several AMGs that were identified in this study were previously detected in a large-scale analysis including metagenomes from various origins, i.e., different marine sites, wastewater, and the human gut. This supports the theory of globally conserved core AMGs that are spread over virus genomes, regardless of host or environment.
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18
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Isolation and Characterization of a Novel Cyanophage Encoding Multiple Auxiliary Metabolic Genes. Viruses 2022; 14:v14050887. [PMID: 35632629 PMCID: PMC9146016 DOI: 10.3390/v14050887] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 04/15/2022] [Accepted: 04/20/2022] [Indexed: 02/04/2023] Open
Abstract
As significant drivers of cyanobacteria mortality, cyanophages have been known to regulate the population dynamics, metabolic activities, and community structure of this most important marine autotrophic picoplankton and, therefore, influence the global primary production and biogeochemical cycle in aquatic ecosystems. In the present study, a lytic Synechococcus phage, namely S-SZBM1, was isolated and identified. Cyanophage S-SZBM1 has a double-stranded DNA genome of 177,834 bp with a G+C content of 43.31% and contains a total of 218 predicted ORFs and six tRNA genes. Phylogenetic analysis and nucleotide-based intergenomic similarity suggested that cyanophage S-SZBM1 belongs to a new genus under the family Kyanoviridae. A variety of auxiliary metabolic genes (AMGs) that have been proved or speculated to relate to photosynthesis, carbon metabolism, nucleotide synthesis and metabolism, cell protection, and other cell metabolism were identified in cyanophage S-SZBM1 genome and may affect host processes during infection. In addition, 24 of 32 predicted structural proteins were identified by a high-throughput proteome analysis which were potentially involved in the assembly processes of virion. The genomic and proteomic analysis features of cyanophage S-SZBM1 offer a valuable insight into the interactions between cyanophages and their hosts during infection.
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19
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Viral community analysis in a marine oxygen minimum zone indicates increased potential for viral manipulation of microbial physiological state. THE ISME JOURNAL 2022; 16:972-982. [PMID: 34743175 PMCID: PMC8940887 DOI: 10.1038/s41396-021-01143-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 10/11/2021] [Accepted: 10/13/2021] [Indexed: 11/08/2022]
Abstract
Microbial communities in oxygen minimum zones (OMZs) are known to have significant impacts on global biogeochemical cycles, but viral influence on microbial processes in these regions are much less studied. Here we provide baseline ecological patterns using microscopy and viral metagenomics from the Eastern Tropical North Pacific (ETNP) OMZ region that enhance our understanding of viruses in these climate-critical systems. While extracellular viral abundance decreased below the oxycline, viral diversity and lytic infection frequency remained high within the OMZ, demonstrating that viral influences on microbial communities were still substantial without the detectable presence of oxygen. Viral community composition was strongly related to oxygen concentration, with viral populations in low-oxygen portions of the water column being distinct from their surface layer counterparts. However, this divergence was not accompanied by the expected differences in viral-encoded auxiliary metabolic genes (AMGs) relating to nitrogen and sulfur metabolisms that are known to be performed by microbial communities in these low-oxygen and anoxic regions. Instead, several abundant AMGs were identified in the oxycline and OMZ that may modulate host responses to low-oxygen stress. We hypothesize that this is due to selection for viral-encoded genes that influence host survivability rather than modulating host metabolic reactions within the ETNP OMZ. Together, this study shows that viruses are not only diverse throughout the water column in the ETNP, including the OMZ, but their infection of microorganisms has the potential to alter host physiological state within these biogeochemically important regions of the ocean.
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20
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Record-Breaking Rain Event Altered Estuarine Viral Assemblages. Microorganisms 2022; 10:microorganisms10040729. [PMID: 35456780 PMCID: PMC9025952 DOI: 10.3390/microorganisms10040729] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 03/24/2022] [Accepted: 03/25/2022] [Indexed: 02/06/2023] Open
Abstract
Viruses are the dominant biological entity in the ocean, play a vital role in biogeochemical cycles, and provide their hosts with novel metabolic capabilities through auxiliary metabolic genes (AMGs). Hurricane Harvey was a category 4 hurricane that made landfall on the Texas coast in 2017 and lashed the Houston area with 1.4–1.7 × 1010 m3 of rainfall. In this paper, we aim to characterize how the changes in abiotic conditions brought by Hurricane Harvey altered the viral assemblages of Galveston Bay at the taxonomic level and determine how viral ecosystem functions were altered. Metagenomes of the viruses and their hosts were sequenced from a transect in Galveston Bay over the five weeks following the storm. Our results show that the viral assemblages of Galveston Bay dramatically changed following Hurricane Harvey’s landfall. Of the abiotic parameters measured, salinity had the strongest effect on shaping the viral assemblages. In the five weeks following Hurricane Harvey, there was a steady increase of metabolic genes and putative viral infections. Our study provides the first in-depth look at how marine viral assemblages respond and recover from extreme rainfall events, which models predict will become more frequent and intense with climate change.
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21
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Wang L, Zhao J, Wang Z, Li N, Song J, Zhang R, Jiao N, Zhang Y. phoH-carrying virus communities responded to multiple factors and their correlation network with prokaryotes in sediments along Bohai Sea, Yellow Sea, and East China Sea in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 812:152477. [PMID: 34952046 DOI: 10.1016/j.scitotenv.2021.152477] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 11/18/2021] [Accepted: 12/13/2021] [Indexed: 06/14/2023]
Abstract
Viruses carrying phoH genes are an important functional group that may boost phosphate metabolism of their prokaryote hosts and affect phosphorus cycle in the ocean. However, at present, very little is known about the phoH-carrying viruses' community structure and diversity in marine sediments, as well as their correlation network with prokaryotes and environment. Here, via a large spatial scale investigation along the Bohai Sea, Yellow Sea, and East China Sea, for the first time, diverse unknown benthic phoH-carrying viruses were uncovered, which were mainly affiliated to three clusters. Interestingly, these viruses presented a very distinct community structure compared to those in seawaters. Correlation network analysis implied that these viruses might mainly infect the prokaryotes of Gamm-/Delta-proteobacteria, Thaumarchaeota, and Cyanobacteria in sediments. Distinct virus-prokaryote correlation network modules were shown in different sea areas. These modules' highly nested feature implied their coevolution with prokaryotes during long-term arms race. Their distribution in sediments was influenced by multiple factors including geographic separation and the key environmental variables of total organic carbon and total phosphorus, and responded to terrestrial inputs and coastal aquaculture activities. The results of this study provide novel insights into the benthic virus communities potentially participating in phosphorus cycling in the ocean.
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Affiliation(s)
- Long Wang
- Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China; Institute of Marine Microbes and Ecospheres, State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361101, China
| | - Jiulong Zhao
- Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zengmeng Wang
- Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ning Li
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Jinming Song
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Rui Zhang
- Institute of Marine Microbes and Ecospheres, State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361101, China
| | - Nianzhi Jiao
- Institute of Marine Microbes and Ecospheres, State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361101, China
| | - Yongyu Zhang
- Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Energy Genetics, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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22
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Genetic engineering of marine cyanophages reveals integration but not lysogeny in T7-like cyanophages. THE ISME JOURNAL 2022; 16:488-499. [PMID: 34429521 PMCID: PMC8776855 DOI: 10.1038/s41396-021-01085-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Revised: 08/02/2021] [Accepted: 08/03/2021] [Indexed: 02/07/2023]
Abstract
Marine cyanobacteria of the genera Synechococcus and Prochlorococcus are the most abundant photosynthetic organisms on earth, spanning vast regions of the oceans and contributing significantly to global primary production. Their viruses (cyanophages) greatly influence cyanobacterial ecology and evolution. Although many cyanophage genomes have been sequenced, insight into the functional role of cyanophage genes is limited by the lack of a cyanophage genetic engineering system. Here, we describe a simple, generalizable method for genetic engineering of cyanophages from multiple families, that we named REEP for REcombination, Enrichment and PCR screening. This method enables direct investigation of key cyanophage genes, and its simplicity makes it adaptable to other ecologically relevant host-virus systems. T7-like cyanophages often carry integrase genes and attachment sites, yet exhibit lytic infection dynamics. Here, using REEP, we investigated their ability to integrate and maintain a lysogenic life cycle. We found that these cyanophages integrate into the host genome and that the integrase and attachment site are required for integration. However, stable lysogens did not form. The frequency of integration was found to be low in both lab cultures and the oceans. These findings suggest that T7-like cyanophage integration is transient and is not part of a classical lysogenic cycle.
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23
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Vladimirov M, Gautam V, Davidson AR. Identification of the tail assembly chaperone genes of T4-Like phages suggests a mechanism other than translational frameshifting for biogenesis of their encoded proteins. Virology 2021; 566:9-15. [PMID: 34826709 DOI: 10.1016/j.virol.2021.11.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 11/11/2021] [Accepted: 11/11/2021] [Indexed: 11/29/2022]
Abstract
Tape measure (TM) proteins are essential for the formation of long-tailed phages. TM protein assembly into tails requires the action of tail assembly chaperones (TACs). TACs (e.g. gpG and gpT of E. coli phage lambda) are usually produced in a short (TAC-N) and long form (TAC-NC) with the latter comprised of TAC-N with an additional C-terminal domain (TAC-C). TAC-NC is generally synthesized through a ribosomal frameshifting mechanism. TAC encoding genes have never been identified in the intensively studied Escherichia coli phage T4, or any related phages. Here, we have bioinformatically identified putative TAC encoding genes in diverse T4-like phage genomes. The frameshifting mechanism for producing TAC-NC appears to be conserved in several T4-like phage groups. However, the group including phage T4 itself likely employs a different strategy whereby TAC-N and TAC-NC are encoded by separate genes (26 and 51 in phage T4).
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Affiliation(s)
- Maria Vladimirov
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Vasu Gautam
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Alan R Davidson
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada; Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada.
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Dutilh BE, Varsani A, Tong Y, Simmonds P, Sabanadzovic S, Rubino L, Roux S, Muñoz AR, Lood C, Lefkowitz EJ, Kuhn JH, Krupovic M, Edwards RA, Brister JR, Adriaenssens EM, Sullivan MB. Perspective on taxonomic classification of uncultivated viruses. Curr Opin Virol 2021; 51:207-215. [PMID: 34781105 DOI: 10.1016/j.coviro.2021.10.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 10/26/2021] [Accepted: 10/27/2021] [Indexed: 12/19/2022]
Abstract
Historically, virus taxonomy has been limited to describing viruses that were readily cultivated in the laboratory or emerging in natural biomes. Metagenomic analyses, single-particle sequencing, and database mining efforts have yielded new sequence data on an astounding number of previously unknown viruses. As metagenomes are relatively free of biases, these data provide an unprecedented insight into the vastness of the virosphere, but to properly value the extent of this diversity it is critical that the viruses are taxonomically classified. Inclusion of uncultivated viruses has already improved the process as well as the understanding of the taxa, viruses, and their evolutionary relationships. The continuous development and testing of computational tools will be required to maintain a dynamic virus taxonomy that can accommodate the new discoveries.
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Affiliation(s)
- Bas E Dutilh
- Theoretical Biology and Bioinformatics, Science for Life, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands; Institute of Bioloversity, Faculty of Biological Sciences, Cluster of Excellence Balance of the Microverse, Friedrich-Schiller-University Jena, 07743, Jena, Germany.
| | - Arvind Varsani
- The Biodesign Center of Fundamental and Applied Microbiomics, School of Life Sciences, Center for Evolution and Medicine, Arizona State University, Tempe, AZ 85287, USA; Structural Biology Research Unit, Department of Integrative Biomedical Sciences, University of Cape Town, 7925, Cape Town, South Africa
| | - Yigang Tong
- Beijing Advanced Innovation Centre for Soft Matter Science and Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Peter Simmonds
- Nuffield Department of Medicine, University of Oxford, Peter Medawar Building, South Parks Road, Oxford, OX1 3SY, UK
| | - Sead Sabanadzovic
- Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, MS 39762, USA
| | - Luisa Rubino
- Istituto per la Protezione Sostenibile delle Piante, Consiglio Nazionale delle Ricerche, Bari, Italy
| | - Simon Roux
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Alejandro Reyes Muñoz
- Max Planck Tandem Group in Computational Biology, Department of Biological Sciences, Universidad de los Andes, Bogotá, Colombia
| | - Cédric Lood
- Department of Microbial and Molecular Systems, KU Leuven, Kasteelpark Arenberg 23, 3001, Leuven, Belgium; Department of Biosystems, KU Leuven, Willem de Croylaan 42, 3001, Leuven, Belgium
| | - Elliot J Lefkowitz
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Jens H Kuhn
- Integrated Research Facility at Fort Detrick, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Fort Detrick, Frederick, MD 21702, USA
| | - Mart Krupovic
- Institut Pasteur, Université de Paris, Archaeal Virology Unit, F-75015, Paris, France
| | - Robert A Edwards
- College of Science and Engineering, Flinders University, Bedford Park, SA 5042, Australia
| | - J Rodney Brister
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda MD 20894, USA
| | | | - Matthew B Sullivan
- Departments of Microbiology and Civil, Environmental, and Geodetic Engineering, Ohio State University, Columbus, OH, USA
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25
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Liu Y, Demina TA, Roux S, Aiewsakun P, Kazlauskas D, Simmonds P, Prangishvili D, Oksanen HM, Krupovic M. Diversity, taxonomy, and evolution of archaeal viruses of the class Caudoviricetes. PLoS Biol 2021; 19:e3001442. [PMID: 34752450 PMCID: PMC8651126 DOI: 10.1371/journal.pbio.3001442] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 12/07/2021] [Accepted: 10/17/2021] [Indexed: 11/19/2022] Open
Abstract
The archaeal tailed viruses (arTV), evolutionarily related to tailed double-stranded DNA (dsDNA) bacteriophages of the class Caudoviricetes, represent the most common isolates infecting halophilic archaea. Only a handful of these viruses have been genomically characterized, limiting our appreciation of their ecological impacts and evolution. Here, we present 37 new genomes of haloarchaeal tailed virus isolates, more than doubling the current number of sequenced arTVs. Analysis of all 63 available complete genomes of arTVs, which we propose to classify into 14 new families and 3 orders, suggests ancient divergence of archaeal and bacterial tailed viruses and points to an extensive sharing of genes involved in DNA metabolism and counterdefense mechanisms, illuminating common strategies of virus-host interactions with tailed bacteriophages. Coupling of the comparative genomics with the host range analysis on a broad panel of haloarchaeal species uncovered 4 distinct groups of viral tail fiber adhesins controlling the host range expansion. The survey of metagenomes using viral hallmark genes suggests that the global architecture of the arTV community is shaped through recurrent transfers between different biomes, including hypersaline, marine, and anoxic environments.
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Affiliation(s)
- Ying Liu
- Institut Pasteur, Université de Paris, Archaeal Virology Unit, Paris, France
| | - Tatiana A. Demina
- Molecular and Integrative Biosciences Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Simon Roux
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America
| | - Pakorn Aiewsakun
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand
- Pornchai Matangkasombut Center for Microbial Genomics, Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Darius Kazlauskas
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Vilnius, Lithuania
| | - Peter Simmonds
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - David Prangishvili
- Institut Pasteur, Université de Paris, Archaeal Virology Unit, Paris, France
- Ivane Javakhishvili Tbilisi State University, Tbilisi, Georgia
| | - Hanna M. Oksanen
- Molecular and Integrative Biosciences Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Mart Krupovic
- Institut Pasteur, Université de Paris, Archaeal Virology Unit, Paris, France
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26
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Ma R, Lai J, Chen X, Wang L, Yang Y, Wei S, Jiao N, Zhang R. A Novel Phage Infecting Alteromonas Represents a Distinct Group of Siphophages Infecting Diverse Aquatic Copiotrophs. mSphere 2021; 6:e0045421. [PMID: 34106770 PMCID: PMC8265664 DOI: 10.1128/msphere.00454-21] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 05/19/2021] [Indexed: 12/14/2022] Open
Abstract
Bacteriophages play critical roles in impacting microbial community succession both ecologically and evolutionarily. Although the majority of phage genetic diversity has been increasingly unveiled, phages infecting members of the ecologically important genus Alteromonas remain poorly understood. Here, we present a comprehensive analysis of a newly isolated alterophage, vB_AcoS-R7M (R7M), to characterize its life cycle traits, genomic features, and putative evolutionary origin. R7M harbors abundant genes identified as host-like auxiliary metabolic genes facilitating viral propagation. Genomic analysis suggested that R7M is distinct from currently known alterophages. Interestingly, R7M was found to share a set of similar characteristics with a number of siphophages infecting diverse aquatic opportunistic copiotrophs. We therefore proposed the creation of one new subfamily (Queuovirinae) to group with these evolutionarily related phages. Notably, tail genes were less likely to be shared among them, and baseplate-related genes varied the most. In-depth analyses indicated that R7M has replaced its distal tail with a Rhodobacter capsulatus gene transfer agent (RcGTA)-like baseplate and further acquired a putative receptor interaction site targeting Alteromonas. These findings suggest that horizontal exchanges of viral tail adsorption apparatuses are widespread and vital for phages to hunt new hosts and to adapt to new niches. IMPORTANCE The evolution and ecology of phages infecting members of Alteromonas, a marine opportunistic genus that is widely distributed and of great ecological significance, remain poorly understood. The present study integrates physiological and genomic evidence to characterize the properties and putative phage-host interactions of a newly isolated Alteromonas phage, vB_AcoS-R7M (R7M). A taxonomic study reveals close evolutionary relationships among R7M and a number of siphophages infecting various aquatic copiotrophs. Their similar head morphology and overall genetic framework suggest their putative common ancestry and the grouping of a new viral subfamily. However, their major difference lies in the viral tail adsorption apparatuses and the horizontal exchanges of which possibly account for variations in host specificity. These findings outline an evolutionary scenario for the emergence of diverse viral lineages of a shared genetic pool and give insights into the genetics and ecology of viral host jumps.
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Affiliation(s)
- Ruijie Ma
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen, China
| | - Jiayong Lai
- College of Ocean and Earth Sciences, Xiamen University, Xiamen, China
| | - Xiaowei Chen
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen, China
| | - Long Wang
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen, China
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
| | - Yahui Yang
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen, China
| | - Shuzhen Wei
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen, China
| | - Nianzhi Jiao
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen, China
| | - Rui Zhang
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen, China
- Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
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27
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Mangalea MR, Paez-Espino D, Kieft K, Chatterjee A, Chriswell ME, Seifert JA, Feser ML, Demoruelle MK, Sakatos A, Anantharaman K, Deane KD, Kuhn KA, Holers VM, Duerkop BA. Individuals at risk for rheumatoid arthritis harbor differential intestinal bacteriophage communities with distinct metabolic potential. Cell Host Microbe 2021; 29:726-739.e5. [PMID: 33957082 PMCID: PMC8186507 DOI: 10.1016/j.chom.2021.03.020] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 03/12/2021] [Accepted: 03/30/2021] [Indexed: 02/08/2023]
Abstract
Rheumatoid arthritis (RA) is an autoimmune disease characterized in seropositive individuals by the presence of anti-cyclic citrullinated protein (CCP) antibodies. RA is linked to the intestinal microbiota, yet the association of microbes with CCP serology and their contribution to RA is unclear. We describe intestinal phage communities of individuals at risk for developing RA, with or without anti-CCP antibodies, whose first-degree relatives have been diagnosed with RA. We show that at-risk individuals harbor intestinal phage compositions that diverge based on CCP serology, are dominated by Streptococcaceae, Bacteroidaceae, and Lachnospiraceae phages, and may originate from disparate ecosystems. These phages encode unique repertoires of auxiliary metabolic genes, which associate with anti-CCP status, suggesting that these phages directly influence the metabolic and immunomodulatory capability of the microbiota. This work sets the stage for the use of phages as preclinical biomarkers and provides insight into a possible microbial-based causation of RA disease development.
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Affiliation(s)
- Mihnea R Mangalea
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | | | - Kristopher Kieft
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53715, USA
| | - Anushila Chatterjee
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Meagan E Chriswell
- Division of Rheumatology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Jennifer A Seifert
- Division of Rheumatology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Marie L Feser
- Division of Rheumatology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - M Kristen Demoruelle
- Division of Rheumatology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | | | - Karthik Anantharaman
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53715, USA
| | - Kevin D Deane
- Division of Rheumatology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Kristine A Kuhn
- Division of Rheumatology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - V Michael Holers
- Division of Rheumatology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Breck A Duerkop
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045, USA.
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28
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Nikulin NA, Zimin AA. Influence of Non-canonical DNA Bases on the Genomic Diversity of Tevenvirinae. Front Microbiol 2021; 12:632686. [PMID: 33889139 PMCID: PMC8056088 DOI: 10.3389/fmicb.2021.632686] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 03/08/2021] [Indexed: 12/03/2022] Open
Abstract
The Tevenvirinae viruses are some of the most common viruses on Earth. Representatives of this subfamily have long been used in the molecular biology studies as model organisms – since the emergence of the discipline. Tevenvirinae are promising agents for phage therapy in animals and humans, since their representatives have only lytic life cycle and many of their host bacteria are pathogens. As confirmed experimentally, some Tevenvirinae have non-canonical DNA bases. Non-canonical bases can play an essential role in the diversification of closely related viruses. The article performs a comparative and evolutionary analysis of Tevenvirinae genomes and components of Tevenvirinae genomes. A comparative analysis of these genomes and the genes associated with the synthesis of non-canonical bases allows us to conclude that non-canonical bases have a major influence on the divergence of Tevenvirinae viruses within the same habitats. Supposedly, Tevenvirinae developed a strategy for changing HGT frequency in individual populations, which was based on the accumulation of proteins for the synthesis of non-canonical bases and proteins that used those bases as substrates. Owing to this strategy, ancestors of Tevenvirinae with the highest frequency of HGT acquired genes that allowed them to exist in a certain niche, and ancestors with the lowest HGT frequency preserved the most adaptive of those genes. Given the origin and characteristics of genes associated with the synthesis of non-canonical bases in Tevenvirinae, one can assume that other phages may have similar strategies. The article demonstrates the dependence of genomic diversity of closely related Tevenvirinae on non-canonical bases.
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Affiliation(s)
- Nikita A Nikulin
- Laboratory of Bacteriophage Biology, G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences, Pushchino, Russia
| | - Andrei A Zimin
- Laboratory of Molecular Microbiology, G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences, Pushchino, Russia
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29
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Huang X, Jiao N, Zhang R. The genomic content and context of auxiliary metabolic genes in roseophages. Environ Microbiol 2021; 23:3743-3757. [PMID: 33511765 DOI: 10.1111/1462-2920.15412] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 01/24/2021] [Indexed: 11/26/2022]
Abstract
Marine bacteriophages frequently possess auxiliary metabolic genes (AMGs) that accelerate host metabolism during phage infection. The significance of AMGs in phage infecting the ecologically important Roseobacter clade, found predominantly in marine environments, remains to be determined. Here, we analysed the distribution and genomic context of 180 AMGs, annotated into 20 types, across 50 roseophage genomes. Roseophages share seven high-frequency AMGs (trx, grx, RNR, thyX, DCD, phoH, and mazG), most of them involved in the nucleotide biosynthesis pathway that represent conserved intra and inter operational taxonomic units (OTUs), and share ≥97% full-length DNA sequence similarity. Sporadic AMGs (dUTPase, lexA, degS, Que, NAPRT, AHL, pcnB, ctrA, RTX, RNR-nrdA, RNR-nrdE, wclP, and flgJ), present in only one or two OTUs, show high functional diversity. The roseophage AMG repertoire weakly correlates with environmental factors, while host range partially explains the sporadic AMG distribution. Locally co-linear blocks distribution index (LDI) analysis indicated that high-frequency roseopodovirus AMGs are restricted to particular genomic islands, possibly originating from limited historical acquisition events. Low-frequency roseopodovirus AMGs and all roseosiphovirus AMGs have high LDI values, implying multiple historical acquisition events. In summary, roseophages have acquired a range of AMGs through horizontal gene transfer, and the forces shaping the evolution of roseophages are described.
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Affiliation(s)
- Xingyu Huang
- State Key Laboratory of Marine Environmental Science, Fujian Key Laboratory of Marine Carbon Sequestration, College of Ocean & Earth Sciences, Xiamen University, Xiamen, 361102, China
| | - Nianzhi Jiao
- State Key Laboratory of Marine Environmental Science, Fujian Key Laboratory of Marine Carbon Sequestration, College of Ocean & Earth Sciences, Xiamen University, Xiamen, 361102, China
| | - Rui Zhang
- State Key Laboratory of Marine Environmental Science, Fujian Key Laboratory of Marine Carbon Sequestration, College of Ocean & Earth Sciences, Xiamen University, Xiamen, 361102, China
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30
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Predetermined clockwork microbial worlds: Current understanding of aquatic microbial diel response from model systems to complex environments. ADVANCES IN APPLIED MICROBIOLOGY 2020; 113:163-191. [PMID: 32948266 DOI: 10.1016/bs.aambs.2020.06.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
In the photic zone of aquatic ecosystems, microorganisms with different metabolisms and their viruses form complex interactions and food webs. Within these interactions, phototrophic microorganisms such as eukaryotic microalgae and cyanobacteria interact directly with sunlight, and thereby generate circadian rhythms. Diel cycling originally generated in microbial phototrophs is directly transmitted toward heterotrophic microorganisms utilizing the photosynthetic products as they are excreted or exuded. Such diel cycling seems to be indirectly propagated toward heterotrophs as a result of complex biotic interactions. For example, cell death of phototrophic microorganisms induced by viral lysis and protistan grazing provides additional resources of dissolved organic matter to the microbial community, and so generates diel cycling in other heterotrophs with different nutrient dependencies. Likewise, differences in the diel transmitting pathway via complex interactions among heterotrophs, and between heterotrophs and their viruses, may also generate higher variation and time lag diel rhythms in different heterotrophic taxa. Thus, sunlight and photosynthesis not only contribute energy and carbon supply, but also directly or indirectly control diel cycling of the microbial community through complex interactions in the photic zone of aquatic ecosystems.
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31
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Fuchsman CA, Carlson MCG, Garcia Prieto D, Hays MD, Rocap G. Cyanophage host-derived genes reflect contrasting selective pressures with depth in the oxic and anoxic water column of the Eastern Tropical North Pacific. Environ Microbiol 2020; 23:2782-2800. [PMID: 32869473 DOI: 10.1111/1462-2920.15219] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 08/14/2020] [Accepted: 08/27/2020] [Indexed: 01/19/2023]
Abstract
Cyanophages encode host-derived genes that may increase their fitness. We examined the relative abundance of 18 host-derived cyanophages genes in metagenomes and viromes along depth profiles from the Eastern Tropical North Pacific Oxygen Deficient Zone (ETNP ODZ) where Prochlorococcus dominates a secondary chlorophyll maximum within the ODZ. Cyanophages at the oxic primary chlorophyll maximum encoded genes related to light and phosphate stress (psbA, psbD and pstS in T4-like and psbA in T7-like), but the proportion of cyanophage with these genes decreased with depth. The proportion of cyanophage with purine biosynthesis genes increased with depth in T4-like, but not T7-like cyanophages. No additional host-derived genes were found in deep T7-like cyanophages, suggesting that T4-like and T7-like cyanophages have different host-derived gene acquisition strategies, possibly linked to their different genome packaging mechanisms. In contrast to the ETNP, in the oxic North Atlantic T4-like cyanophages encoded psbA and pstS throughout the euphotic zone. Differences in pstS between the ETNP and the North Atlantic stations were consistent with differences in phosphate concentrations in those regimes. We suggest that the low proportion of cyanophage with psbA within the ODZ reflects the stably stratified low-light conditions occupied by their hosts, a Prochlorococcus ecotype endemic to ODZs.
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Affiliation(s)
- Clara A Fuchsman
- School of Oceanography, University of Washington, Seattle, WA, USA.,Horn Point Laboratory, University of Maryland Center of Environmental Science, Cambridge, MD, 21613, USA
| | - Michael C G Carlson
- School of Oceanography, University of Washington, Seattle, WA, USA.,Technion-Israel Institute of Technology, Haifa, Israel
| | - David Garcia Prieto
- School of Oceanography, University of Washington, Seattle, WA, USA.,Horn Point Laboratory, University of Maryland Center of Environmental Science, Cambridge, MD, 21613, USA
| | - Matthew D Hays
- Horn Point Laboratory, University of Maryland Center of Environmental Science, Cambridge, MD, 21613, USA
| | - Gabrielle Rocap
- School of Oceanography, University of Washington, Seattle, WA, USA
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32
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Zhong ZP, Rapp JZ, Wainaina JM, Solonenko NE, Maughan H, Carpenter SD, Cooper ZS, Jang HB, Bolduc B, Deming JW, Sullivan MB. Viral Ecogenomics of Arctic Cryopeg Brine and Sea Ice. mSystems 2020; 5:e00246-20. [PMID: 32546670 PMCID: PMC7300359 DOI: 10.1128/msystems.00246-20] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 05/24/2020] [Indexed: 01/09/2023] Open
Abstract
Arctic regions, which are changing rapidly as they warm 2 to 3 times faster than the global average, still retain microbial habitats that serve as natural laboratories for understanding mechanisms of microbial adaptation to extreme conditions. Seawater-derived brines within both sea ice (sea-ice brine) and ancient layers of permafrost (cryopeg brine) support diverse microbes adapted to subzero temperatures and high salinities, yet little is known about viruses in these extreme environments, which, if analogous to other systems, could play important evolutionary and ecosystem roles. Here, we characterized viral communities and their functions in samples of cryopeg brine, sea-ice brine, and melted sea ice. Viral abundance was high in cryopeg brine (1.2 × 108 ml-1) and much lower in sea-ice brine (1.3 × 105 to 2.1 × 105 ml-1), which roughly paralleled the differences in cell concentrations in these samples. Five low-input, quantitative viral metagenomes were sequenced to yield 476 viral populations (i.e., species level; ≥10 kb), only 12% of which could be assigned taxonomy by traditional database approaches, indicating a high degree of novelty. Additional analyses revealed that these viruses: (i) formed communities that differed between sample type and vertically with sea-ice depth; (ii) infected hosts that dominated these extreme ecosystems, including Marinobacter, Glaciecola, and Colwellia; and (iii) encoded fatty acid desaturase (FAD) genes that likely helped their hosts overcome cold and salt stress during infection, as well as mediated horizontal gene transfer of FAD genes between microbes. Together, these findings contribute to understanding viral abundances and communities and how viruses impact their microbial hosts in subzero brines and sea ice.IMPORTANCE This study explores viral community structure and function in remote and extreme Arctic environments, including subzero brines within marine layers of permafrost and sea ice, using a modern viral ecogenomics toolkit for the first time. In addition to providing foundational data sets for these climate-threatened habitats, we found evidence that the viruses had habitat specificity, infected dominant microbial hosts, encoded host-derived metabolic genes, and mediated horizontal gene transfer among hosts. These results advance our understanding of the virosphere and how viruses influence extreme ecosystems. More broadly, the evidence that virally mediated gene transfers may be limited by host range in these extreme habitats contributes to a mechanistic understanding of genetic exchange among microbes under stressful conditions in other systems.
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Affiliation(s)
- Zhi-Ping Zhong
- Byrd Polar and Climate Research Center, The Ohio State University, Columbus, Ohio, USA
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
| | - Josephine Z Rapp
- School of Oceanography, University of Washington, Seattle, Washington, USA
| | - James M Wainaina
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
| | | | | | - Shelly D Carpenter
- School of Oceanography, University of Washington, Seattle, Washington, USA
| | - Zachary S Cooper
- School of Oceanography, University of Washington, Seattle, Washington, USA
| | - Ho Bin Jang
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
| | - Benjamin Bolduc
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
| | - Jody W Deming
- School of Oceanography, University of Washington, Seattle, Washington, USA
| | - Matthew B Sullivan
- Byrd Polar and Climate Research Center, The Ohio State University, Columbus, Ohio, USA
- Department of Microbiology, The Ohio State University, Columbus, Ohio, USA
- Department of Civil, Environmental and Geodetic Engineering, The Ohio State University, Columbus, Ohio, USA
- Center of Microbiome Science, The Ohio State University, Columbus, Ohio, USA
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33
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Jiang T, Guo C, Wang M, Wang M, You S, Liu Y, Zhang X, Liu H, Jiang Y, Shao H, Liang Y, McMinn A. Isolation and complete genome sequence of a novel cyanophage, S-B05, infecting an estuarine Synechococcus strain: insights into environmental adaptation. Arch Virol 2020; 165:1397-1407. [PMID: 32307604 DOI: 10.1007/s00705-020-04595-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Accepted: 02/21/2020] [Indexed: 11/24/2022]
Abstract
A new cyanophage, S-B05, infecting a phycoerythrin-enriched (PE-type) Synechococcus strain was isolated by the liquid infection method, and its morphology and genetic features were examined. Phylogenetic analysis and morphological observation confirmed that S-B05 belongs to the family Myoviridae of the order Caudovirales. Its genome was fully sequenced, and found to be 208,857 bp in length with a G + C content of 39.9%. It contained 280 potential open reading frames and 123 conserved domains. Ninety-eight functional genes responsible for cyanophage structuring and packaging, DNA replication and regulation, and photosynthesis were identified, as well as genes encoding 172 hypothetical proteins. The genome of S-B05 is most similar to that of Prochlorococcus phage P-TIM68. Homologues of open reading frames of S-B05 can be found in various marine environments, as revealed by comparison of the S-B05 genome sequence to sequences in marine viral metagenomic databases. The presence of auxiliary metabolic genes (AMGs) related to photosynthesis, carbon metabolism, and phosphorus assimilation, as well as the phylogenetic relationships based on AMGs and the complete genome sequence, reflect the phage-host interaction mechanism or the specific adaptation strategy of the host to environmental conditions. The genome sequence information reported here will provide an important basis for further study of the adaptive evolution and ecological role of cyanophages and their hosts in the marine environment.
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Affiliation(s)
- Tong Jiang
- College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China
| | - Cui Guo
- College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China. .,Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, 266003, China. .,Key Lab of Polar Oceanography and Global Ocean Change, Ocean University of China, Qingdao, 266003, China.
| | - Min Wang
- College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China.,Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, 266003, China.,Key Lab of Polar Oceanography and Global Ocean Change, Ocean University of China, Qingdao, 266003, China
| | - Meiwen Wang
- College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China
| | - Siyuan You
- College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China
| | - Yundan Liu
- College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China
| | - Xinran Zhang
- College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China
| | - Hongbin Liu
- Department of Ocean Science, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong SAR, China
| | - Yong Jiang
- College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China.,Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, 266003, China.,Key Lab of Polar Oceanography and Global Ocean Change, Ocean University of China, Qingdao, 266003, China
| | - Hongbing Shao
- College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China
| | - Yantao Liang
- College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China.,Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, 266003, China.,Key Lab of Polar Oceanography and Global Ocean Change, Ocean University of China, Qingdao, 266003, China
| | - Andrew McMinn
- College of Marine Life Sciences, Ocean University of China, Qingdao, 266003, China.,Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Australia
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Zimmerman AE, Howard-Varona C, Needham DM, John SG, Worden AZ, Sullivan MB, Waldbauer JR, Coleman ML. Metabolic and biogeochemical consequences of viral infection in aquatic ecosystems. Nat Rev Microbiol 2019; 18:21-34. [PMID: 31690825 DOI: 10.1038/s41579-019-0270-x] [Citation(s) in RCA: 175] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/09/2019] [Indexed: 12/23/2022]
Abstract
Ecosystems are controlled by 'bottom-up' (resources) and 'top-down' (predation) forces. Viral infection is now recognized as a ubiquitous top-down control of microbial growth across ecosystems but, at the same time, cell death by viral predation influences, and is influenced by, resource availability. In this Review, we discuss recent advances in understanding the biogeochemical impact of viruses, focusing on how metabolic reprogramming of host cells during lytic viral infection alters the flow of energy and nutrients in aquatic ecosystems. Our synthesis revealed several emerging themes. First, viral infection transforms host metabolism, in part through virus-encoded metabolic genes; the functions performed by these genes appear to alleviate energetic and biosynthetic bottlenecks to viral production. Second, viral infection depends on the physiological state of the host cell and on environmental conditions, which are challenging to replicate in the laboratory. Last, metabolic reprogramming of infected cells and viral lysis alter nutrient cycling and carbon export in the oceans, although the net impacts remain uncertain. This Review highlights the need for understanding viral infection dynamics in realistic physiological and environmental contexts to better predict their biogeochemical consequences.
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Affiliation(s)
- Amy E Zimmerman
- Department of the Geophysical Sciences, University of Chicago, Chicago, IL, USA
| | | | - David M Needham
- Monterey Bay Aquarium Research Institute, Moss Landing, CA, USA
| | - Seth G John
- Department of Earth Science, University of Southern California, Los Angeles, CA, USA
| | - Alexandra Z Worden
- Monterey Bay Aquarium Research Institute, Moss Landing, CA, USA.,Ocean EcoSystems Biology Unit, GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany
| | - Matthew B Sullivan
- Department of Microbiology, Ohio State University, Columbus, OH, USA.,Department of Civil, Environmental and Geodetic Engineering, Ohio State University, Columbus, OH, USA
| | - Jacob R Waldbauer
- Department of the Geophysical Sciences, University of Chicago, Chicago, IL, USA
| | - Maureen L Coleman
- Department of the Geophysical Sciences, University of Chicago, Chicago, IL, USA.
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Genomic and Seasonal Variations among Aquatic Phages Infecting the Baltic Sea Gammaproteobacterium Rheinheimera sp. Strain BAL341. Appl Environ Microbiol 2019; 85:AEM.01003-19. [PMID: 31324626 PMCID: PMC6715854 DOI: 10.1128/aem.01003-19] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 07/10/2019] [Indexed: 12/25/2022] Open
Abstract
Phages are important in aquatic ecosystems as they influence their microbial hosts through lysis, gene transfer, transcriptional regulation, and expression of phage metabolic genes. Still, there is limited knowledge of how phages interact with their hosts, especially at fine scales. Here, a Rheinheimera phage-host system constituting highly similar phages infecting one host strain is presented. This relatively limited diversity has previously been seen only when smaller numbers of phages have been isolated and points toward ecological constraints affecting the Rheinheimera phage diversity. The variation of metabolic genes among the species points toward various fitness advantages, opening up possibilities for future hypothesis testing. Phage-host dynamics monitored over several years point toward recurring “kill-the-winner” oscillations and an ecological niche fulfilled by this system in the Baltic Sea. Identifying and quantifying ecological dynamics of such phage-host model systems in situ allow us to understand and study the influence of phages on aquatic ecosystems. Knowledge in aquatic virology has been greatly improved by culture-independent methods, yet there is still a critical need for isolating novel phages to identify the large proportion of “unknowns” that dominate metagenomes and for detailed analyses of phage-host interactions. Here, 54 phages infecting Rheinheimera sp. strain BAL341 (Gammaproteobacteria) were isolated from Baltic Sea seawater and characterized through genome content analysis and comparative genomics. The phages showed a myovirus-like morphology and belonged to a novel genus, for which we propose the name Barbavirus. All phages had similar genome sizes and numbers of genes (80 to 84 kb; 134 to 145 genes), and based on average nucleotide identity and genome BLAST distance phylogeny, the phages were divided into five species. The phages possessed several genes involved in metabolic processes and host signaling, such as genes encoding ribonucleotide reductase and thymidylate synthase, phoH, and mazG. One species had additional metabolic genes involved in pyridine nucleotide salvage, possibly providing a fitness advantage by further increasing the phages’ replication efficiency. Recruitment of viral metagenomic reads (25 Baltic Sea viral metagenomes from 2012 to 2015) to the phage genomes showed pronounced seasonal variations, with increased relative abundances of barba phages in August and September synchronized with peaks in host abundances, as shown by 16S rRNA gene amplicon sequencing. Overall, this study provides detailed information regarding genetic diversity, phage-host interactions, and temporal dynamics of an ecologically important aquatic phage-host system. IMPORTANCE Phages are important in aquatic ecosystems as they influence their microbial hosts through lysis, gene transfer, transcriptional regulation, and expression of phage metabolic genes. Still, there is limited knowledge of how phages interact with their hosts, especially at fine scales. Here, a Rheinheimera phage-host system constituting highly similar phages infecting one host strain is presented. This relatively limited diversity has previously been seen only when smaller numbers of phages have been isolated and points toward ecological constraints affecting the Rheinheimera phage diversity. The variation of metabolic genes among the species points toward various fitness advantages, opening up possibilities for future hypothesis testing. Phage-host dynamics monitored over several years point toward recurring “kill-the-winner” oscillations and an ecological niche fulfilled by this system in the Baltic Sea. Identifying and quantifying ecological dynamics of such phage-host model systems in situ allow us to understand and study the influence of phages on aquatic ecosystems.
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36
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Rates of Molecular Evolution in a Marine Synechococcus Phage Lineage. Viruses 2019; 11:v11080720. [PMID: 31390807 PMCID: PMC6722890 DOI: 10.3390/v11080720] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 07/27/2019] [Accepted: 07/31/2019] [Indexed: 12/30/2022] Open
Abstract
Cyanophages are characterized by vast genomic diversity and the formation of stable ecotypes over time. The evolution of phage diversity includes vertical processes, such as mutation, and horizontal processes, such as recombination and gene transfer. Here, we study the contribution of vertical and horizontal processes to short-term evolution of marine cyanophages. Analyzing time series data of Synechococcus-infecting Myoviridae ecotypes spanning up to 17 years, we found a high contribution of recombination relative to mutation (r/m) in all ecotypes. Additionally, we found a molecular clock of substitution and recombination in one ecotype, RIM8. The estimated RIM8 evolutionary rates are 2.2 genome-wide substitutions per year (1.275 × 10−5 substitutions/site/year) and 29 genome-wide nucleotide alterations due to recombination per year. We found 26 variable protein families, of which only two families have a predicted functional annotation, suggesting that they are auxiliary metabolic genes with bacterial homologs. A comparison of our rate estimates to other phage evolutionary rate estimates in the literature reveals a negative correlation of phage substitution rates with their genome size. A comparison to evolutionary rates in bacterial organisms further shows that phages have high rates of mutation and recombination compared to their bacterial hosts. We conclude that the increased recombination rate in phages likely contributes to their vast genomic diversity.
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Expanding the Diversity of Myoviridae Phages Infecting Lactobacillus plantarum-A Novel Lineage of Lactobacillus Phages Comprising Five New Members. Viruses 2019; 11:v11070611. [PMID: 31277436 PMCID: PMC6669764 DOI: 10.3390/v11070611] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 06/07/2019] [Accepted: 07/02/2019] [Indexed: 01/01/2023] Open
Abstract
Lactobacillus plantarum is a bacterium with probiotic properties and promising applications in the food industry and agriculture. So far, bacteriophages of this bacterium have been moderately addressed. We examined the diversity of five new L. plantarum phages via whole genome shotgun sequencing and in silico protein predictions. Moreover, we looked into their phylogeny and their potential genomic similarities to other complete phage genome records through extensive nucleotide and protein comparisons. These analyses revealed a high degree of similarity among the five phages, which extended to the vast majority of predicted virion-associated proteins. Based on these, we selected one of the phages as a representative and performed transmission electron microscopy and structural protein sequencing tests. Overall, the results suggested that the five phages belong to the family Myoviridae, they have a long genome of 137,973-141,344 bp, a G/C content of 36.3-36.6% that is quite distinct from their host's, and surprisingly, 7 to 15 tRNAs. Only an average 41/174 of their predicted genes were assigned a function. The comparative analyses unraveled considerable genetic diversity for the five L. plantarum phages in this study. Hence, the new genus "Semelevirus" was proposed, comprising exclusively of the five phages. This novel lineage of Lactobacillus phages provides further insight into the genetic heterogeneity of phages infecting Lactobacillus sp. The five new Lactobacillus phages have potential value for the development of more robust starters through, for example, the selection of mutants insensitive to phage infections. The five phages could also form part of phage cocktails, which producers would apply in different stages of L. plantarum fermentations in order to create a range of organoleptic outputs.
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38
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Zhao Y, Qin F, Zhang R, Giovannoni SJ, Zhang Z, Sun J, Du S, Rensing C. Pelagiphages in thePodoviridaefamily integrate into host genomes. Environ Microbiol 2018; 21:1989-2001. [DOI: 10.1111/1462-2920.14487] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 11/16/2018] [Accepted: 11/21/2018] [Indexed: 11/28/2022]
Affiliation(s)
- Yanlin Zhao
- Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, College of Life SciencesFujian Agriculture and Forestry University Fuzhou Fujian China
| | - Fang Qin
- Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, College of Life SciencesFujian Agriculture and Forestry University Fuzhou Fujian China
| | - Rui Zhang
- State Key Laboratory of Marine Environmental ScienceCollege of Ocean and Earth Sciences, Institute of Marine Microbes and Ecospheres, Xiamen University Xiamen Fujian China
| | | | - Zefeng Zhang
- Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, College of Life SciencesFujian Agriculture and Forestry University Fuzhou Fujian China
| | - Jing Sun
- Department of MicrobiologyOregon State University Corvallis OR USA
| | - Sen Du
- Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, College of Life SciencesFujian Agriculture and Forestry University Fuzhou Fujian China
| | - Christopher Rensing
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and EnvironmentFujian Agriculture and Forestry University Fuzhou Fujian China
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Zhang QY, Gui JF. Diversity, evolutionary contribution and ecological roles of aquatic viruses. SCIENCE CHINA-LIFE SCIENCES 2018; 61:1486-1502. [DOI: 10.1007/s11427-018-9414-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 09/26/2018] [Indexed: 01/21/2023]
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40
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Enav H, Kirzner S, Lindell D, Mandel-Gutfreund Y, Béjà O. Adaptation to sub-optimal hosts is a driver of viral diversification in the ocean. Nat Commun 2018; 9:4698. [PMID: 30409965 PMCID: PMC6224464 DOI: 10.1038/s41467-018-07164-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 10/22/2018] [Indexed: 12/16/2022] Open
Abstract
Cyanophages of the Myoviridae family include generalist viruses capable of infecting a wide range of hosts including those from different cyanobacterial genera. While the influence of phages on host evolution has been studied previously, it is not known how the infection of distinct hosts influences the evolution of cyanophage populations. Here, using an experimental evolution approach, we investigated the adaptation of multiple cyanophage populations to distinct cyanobacterial hosts. We show that when infecting an "optimal" host, whose infection is the most efficient, phage populations accumulated only a few mutations. However, when infecting "sub-optimal" hosts, different mutations spread in the phage populations, leading to rapid diversification into distinct subpopulations. Based on our results, we propose a model demonstrating how shifts in microbial abundance, which lead to infection of "sub-optimal" hosts, act as a driver for rapid diversification of viral populations.
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Affiliation(s)
- Hagay Enav
- Faculty of Biology, Technion-Israel Institute of Technology, 32000, Haifa, Israel. .,Department of Microbiome Science, Max-Planck Institute for Developmental Biology, 72076, Tübingen, Germany.
| | - Shay Kirzner
- Faculty of Biology, Technion-Israel Institute of Technology, 32000, Haifa, Israel
| | - Debbie Lindell
- Faculty of Biology, Technion-Israel Institute of Technology, 32000, Haifa, Israel
| | - Yael Mandel-Gutfreund
- Faculty of Biology, Technion-Israel Institute of Technology, 32000, Haifa, Israel.,Department of Computer Sciences, Technion-Israel Institute of Technology, 32000, Haifa, Israel
| | - Oded Béjà
- Faculty of Biology, Technion-Israel Institute of Technology, 32000, Haifa, Israel.
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41
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Sieradzki ET, Fuhrman JA, Rivero-Calle S, Gómez-Consarnau L. Proteorhodopsins dominate the expression of phototrophic mechanisms in seasonal and dynamic marine picoplankton communities. PeerJ 2018; 6:e5798. [PMID: 30370186 PMCID: PMC6202958 DOI: 10.7717/peerj.5798] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 09/20/2018] [Indexed: 12/13/2022] Open
Abstract
The most abundant and ubiquitous microbes in the surface ocean use light as an energy source, capturing it via complex chlorophyll-based photosystems or simple retinal-based rhodopsins. Studies in various ocean regimes compared the abundance of these mechanisms, but few investigated their expression. Here we present the first full seasonal study of abundance and expression of light-harvesting mechanisms (proteorhodopsin, PR; aerobic anoxygenic photosynthesis, AAnP; and oxygenic photosynthesis, PSI) from deep-sequenced metagenomes and metatranscriptomes of marine picoplankton (<1 µm) at three coastal stations of the San Pedro Channel in the Pacific Ocean. We show that, regardless of season or sampling location, the most common phototrophic mechanism in metagenomes of this dynamic region was PR (present in 65–104% of the genomes as estimated by single-copy recA), followed by PSI (5–104%) and AAnP (5–32%). Furthermore, the normalized expression (RNA to DNA ratio) of PR genes was higher than that of oxygenic photosynthesis (average ± standard deviation 26.2 ± 8.4 vs. 11 ± 9.7), and the expression of the AAnP marker gene was significantly lower than both mechanisms (0.013 ± 0.02). We demonstrate that PR expression was dominated by the SAR11-cluster year-round, followed by other Alphaproteobacteria, unknown-environmental clusters and Gammaproteobacteria. This highly dynamic system further allowed us to identify a trend for PR spectral tuning, in which blue-absorbing PR genes dominate in areas with low chlorophyll-a concentrations (<0.25 µgL−1). This suggests that PR phototrophy is not an accessory function but instead a central mechanism that can regulate photoheterotrophic population dynamics.
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Affiliation(s)
- Ella T Sieradzki
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, United States of America
| | - Jed A Fuhrman
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, United States of America
| | - Sara Rivero-Calle
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, United States of America
| | - Laura Gómez-Consarnau
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, United States of America
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42
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Ahlgren NA, Fuchsman CA, Rocap G, Fuhrman JA. Discovery of several novel, widespread, and ecologically distinct marine Thaumarchaeota viruses that encode amoC nitrification genes. ISME JOURNAL 2018; 13:618-631. [PMID: 30315316 DOI: 10.1038/s41396-018-0289-4] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 06/15/2018] [Accepted: 09/19/2018] [Indexed: 12/22/2022]
Abstract
Much of the diversity of prokaryotic viruses has yet to be described. In particular, there are no viral isolates that infect abundant, globally significant marine archaea including the phylum Thaumarchaeota. This phylum oxidizes ammonia, fixes inorganic carbon, and thus contributes to globally significant nitrogen and carbon cycles in the oceans. Metagenomics provides an alternative to culture-dependent means for identifying and characterizing viral diversity. Some viruses carry auxiliary metabolic genes (AMGs) that are acquired via horizontal gene transfer from their host(s), allowing inference of what host a virus infects. Here we present the discovery of 15 new genomically and ecologically distinct Thaumarchaeota virus populations, identified as contigs that encode viral capsid and thaumarchaeal ammonia monooxygenase genes (amoC). These viruses exhibit depth and latitude partitioning and are distributed globally in various marine habitats including pelagic waters, estuarine habitats, and hydrothermal plume water and sediments. We found evidence of viral amoC expression and that viral amoC AMGs sometimes comprise up to half of total amoC DNA copies in cellular fraction metagenomes, highlighting the potential impact of these viruses on N cycling in the oceans. Phylogenetics suggest they are potentially tailed viruses and share a common ancestor with related marine Euryarchaeota viruses. This work significantly expands our view of viruses of globally important marine Thaumarchaeota.
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Affiliation(s)
- Nathan A Ahlgren
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA. .,Clark University, Worcester, MA, USA.
| | - Clara A Fuchsman
- School of Oceanography, University of Washington, Seattle, WA, USA.,Horn Point Laboratory, University of Maryland, Cambridge, MD, USA
| | - Gabrielle Rocap
- School of Oceanography, University of Washington, Seattle, WA, USA
| | - Jed A Fuhrman
- Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA
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43
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Xu Y, Zhang R, Wang N, Cai L, Tong Y, Sun Q, Chen F, Jiao N. Novel phage-host interactions and evolution as revealed by a cyanomyovirus isolated from an estuarine environment. Environ Microbiol 2018; 20:2974-2989. [DOI: 10.1111/1462-2920.14326] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 06/09/2018] [Accepted: 06/13/2018] [Indexed: 12/15/2022]
Affiliation(s)
- Yongle Xu
- Institute of Marine Science and Technology; Shandong University; Qingdao China
- School of Life Science; Shandong University; Qingdao China
- Institute of Marine Microbes and Ecospheres; Xiamen University; Xiamen China
| | - Rui Zhang
- Institute of Marine Microbes and Ecospheres; Xiamen University; Xiamen China
- State Key Laboratory of Marine Environmental Sciences, College of Ocean & Earth Sciences; Xiamen University; Xiamen China
| | - Nannan Wang
- Institute of Marine Microbes and Ecospheres; Xiamen University; Xiamen China
- State Key Laboratory of Marine Environmental Sciences, College of Ocean & Earth Sciences; Xiamen University; Xiamen China
| | - Lanlan Cai
- Institute of Marine Microbes and Ecospheres; Xiamen University; Xiamen China
- State Key Laboratory of Marine Environmental Sciences, College of Ocean & Earth Sciences; Xiamen University; Xiamen China
| | - Yigang Tong
- State Key Laboratory of Pathogen and Biosecurity; Beijing Institute of Microbiology and Epidemiology; Beijing China
| | - Qiang Sun
- State Key Laboratory of Pathogen and Biosecurity; Beijing Institute of Microbiology and Epidemiology; Beijing China
| | - Feng Chen
- Institute of Marine Science and Technology; Shandong University; Qingdao China
- Institute of Marine and Environmental Technology; University of Maryland Center for Environmental Science; Baltimore MD USA
| | - Nianzhi Jiao
- Institute of Marine Science and Technology; Shandong University; Qingdao China
- Institute of Marine Microbes and Ecospheres; Xiamen University; Xiamen China
- State Key Laboratory of Marine Environmental Sciences, College of Ocean & Earth Sciences; Xiamen University; Xiamen China
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44
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Godde JS, Baichoo S, Mungloo-Dilmohamud Z, Jaufeerally-Fakim Y. Comparison of genomic islands in cyanobacteria: Evidence of bacteriophage-mediated horizontal gene transfer from eukaryotes. Microbiol Res 2018; 211:31-46. [DOI: 10.1016/j.micres.2018.03.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Revised: 02/11/2018] [Accepted: 03/17/2018] [Indexed: 12/21/2022]
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45
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Hou W, Wang S, Briggs BR, Li G, Xie W, Dong H. High Diversity of Myocyanophage in Various Aquatic Environments Revealed by High-Throughput Sequencing of Major Capsid Protein Gene With a New Set of Primers. Front Microbiol 2018; 9:887. [PMID: 29774020 PMCID: PMC5943533 DOI: 10.3389/fmicb.2018.00887] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2018] [Accepted: 04/18/2018] [Indexed: 12/02/2022] Open
Abstract
Myocyanophages, a group of viruses infecting cyanobacteria, are abundant and play important roles in elemental cycling. Here we investigated the particle-associated viral communities retained on 0.2 μm filters and in sediment samples (representing ancient cyanophage communities) from four ocean and three lake locations, using high-throughput sequencing and a newly designed primer pair targeting a gene fragment (∼145-bp in length) encoding the cyanophage gp23 major capsid protein (MCP). Diverse viral communities were detected in all samples. The fragments of 142-, 145-, and 148-bp in length were most abundant in the amplicons, and most sequences (>92%) belonged to cyanophages. Additionally, different sequencing depths resulted in different diversity estimates of the viral community. Operational taxonomic units obtained from deep sequencing of the MCP gene covered the majority of those obtained from shallow sequencing, suggesting that deep sequencing exhibited a more complete picture of cyanophage community than shallow sequencing. Our results also revealed a wide geographic distribution of marine myocyanophages, i.e., higher dissimilarities of the myocyanophage communities corresponded with the larger distances between the sampling sites. Collectively, this study suggests that the newly designed primer pair can be effectively used to study the community and diversity of myocyanophage from different environments, and the high-throughput sequencing represents a good method to understand viral diversity.
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Affiliation(s)
- Weiguo Hou
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing, China
| | - Shang Wang
- CAS Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences (CAS), Beijing, China
| | - Brandon R Briggs
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK, United States
| | - Gaoyuan Li
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing, China
| | - Wei Xie
- State Key Laboratory of Marine Geology, Tongji University, Shanghai, China
| | - Hailiang Dong
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing, China.,Department of Geology and Environmental Earth Science, Miami University, Oxford, OH, United States
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46
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Chrismas NAM, Anesio AM, Sánchez-Baracaldo P. The future of genomics in polar and alpine cyanobacteria. FEMS Microbiol Ecol 2018; 94:4904125. [PMID: 29506259 PMCID: PMC5939894 DOI: 10.1093/femsec/fiy032] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Accepted: 02/23/2018] [Indexed: 01/01/2023] Open
Abstract
In recent years, genomic analyses have arisen as an exciting way of investigating the functional capacity and environmental adaptations of numerous micro-organisms of global relevance, including cyanobacteria. In the extreme cold of Arctic, Antarctic and alpine environments, cyanobacteria are of fundamental ecological importance as primary producers and ecosystem engineers. While their role in biogeochemical cycles is well appreciated, little is known about the genomic makeup of polar and alpine cyanobacteria. In this article, we present ways that genomic techniques might be used to further our understanding of cyanobacteria in cold environments in terms of their evolution and ecology. Existing examples from other environments (e.g. marine/hot springs) are used to discuss how methods developed there might be used to investigate specific questions in the cryosphere. Phylogenomics, comparative genomics and population genomics are identified as methods for understanding the evolution and biogeography of polar and alpine cyanobacteria. Transcriptomics will allow us to investigate gene expression under extreme environmental conditions, and metagenomics can be used to complement tradition amplicon-based methods of community profiling. Finally, new techniques such as single cell genomics and metagenome assembled genomes will also help to expand our understanding of polar and alpine cyanobacteria that cannot readily be cultured.
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Affiliation(s)
- Nathan A M Chrismas
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, University Road, Bristol, BS8 1SS, UK
- Marine Biological Association of the United Kingdom, The Laboratory, Citadel Hill, Plymouth, PL1 2PB, UK
| | - Alexandre M Anesio
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, University Road, Bristol, BS8 1SS, UK
| | - Patricia Sánchez-Baracaldo
- Bristol Glaciology Centre, School of Geographical Sciences, University of Bristol, University Road, Bristol, BS8 1SS, UK
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47
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Liu L, Cai L, Zhang R. Co-existence of freshwater and marine T4-like myoviruses in a typical subtropical estuary. FEMS Microbiol Ecol 2018; 93:4584463. [PMID: 29099976 DOI: 10.1093/femsec/fix119] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 09/14/2017] [Indexed: 11/13/2022] Open
Abstract
Viruses are the most abundant biological entities on Earth and play an important role in microbial community dynamics and biogeochemical cycling, yet their ecological characteristics in estuarine ecosystems are unclear. Here, virioplankton communities in a typical subtropical estuary, the Jiulong River estuary (JRE) in China, were investigated. The abundance of virioplankton ranged from 1.01 ± 0.05 × 107 to 1.62 ± 0.09 × 107 particles mL-1 in JRE, and the population size of viruses was correlated with temperature and nutrient levels. Three tailed viral morphotypes (myovirus, siphovirus and podovirus) were observed. Phylogenetic analysis showed that most of the g23 sequences in the JRE fell into three previously established groups (Marine, Paddy and Lake Groups) and two potential Estuary Groups. This demonstrates the co-existence of typical freshwater and marine T4-like myoviruses in the estuarine ecosystem, suggesting the movement of viruses and their hosts among biomes. Additionally, the spatial variation of g23 sequences suggests a geographic distribution pattern of T4-like myoviruses in the JRE, which might be shaped by the environmental gradient and/or their host distribution. These results provide valuable insights into the abundance, diversity and distribution patterns of virioplankton, as well as the factors influencing them, in subtropical estuarine ecosystems.
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Affiliation(s)
- Lu Liu
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiang'an, Xiamen, Fujian 361102, People's Republic of China
| | - Lanlan Cai
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiang'an, Xiamen, Fujian 361102, People's Republic of China
| | - Rui Zhang
- State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiang'an, Xiamen, Fujian 361102, People's Republic of China
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The Gut Microbiota Facilitates Drifts in the Genetic Diversity and Infectivity of Bacterial Viruses. Cell Host Microbe 2017; 22:801-808.e3. [PMID: 29174401 DOI: 10.1016/j.chom.2017.10.010] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 09/11/2017] [Accepted: 09/29/2017] [Indexed: 01/12/2023]
Abstract
The intestinal microbiota and human health are intimately linked, but interactions between bacteria and bacteriophages in the context of the mammalian intestine remain largely unexplored. We used comparative population genomics to study a tripartite network consisting of a virulent bacteriophage, its bacterial host, and a phage-insensitive bacterial strain both in vitro and within the murine gut. The bacteriophage adapted to infect the insensitive strain when the three partners co-existed in the gut of conventional mice, but not in dixenic mice or in planktonic cultures. The molecular changes associated with modifications in the bacteriophage host spectrum included single amino acid substitutions and an unusual homologous intragenomic recombination event within the genome of the bacteriophage. An intermediate bacterial host isolated from the murine microbiota mediated bacteriophage adaptation. Our data indicate that by offering access to new hosts, the microbiota shifts the genetic diversity of bacteriophages, thereby promoting long-term persistence of bacteriophage populations.
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Cyanophage-encoded lipid desaturases: oceanic distribution, diversity and function. ISME JOURNAL 2017; 12:343-355. [PMID: 29028002 PMCID: PMC5776448 DOI: 10.1038/ismej.2017.159] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 08/17/2017] [Accepted: 08/22/2017] [Indexed: 11/08/2022]
Abstract
Cyanobacteria are among the most abundant photosynthetic organisms in the oceans; viruses infecting cyanobacteria (cyanophages) can alter cyanobacterial populations, and therefore affect the local food web and global biochemical cycles. These phages carry auxiliary metabolic genes (AMGs), which rewire various metabolic pathways in the infected host cell, resulting in increased phage fitness. Coping with stress resulting from photodamage appears to be a central necessity of cyanophages, yet the overall mechanism is poorly understood. Here we report a novel, widespread cyanophage AMG, encoding a fatty acid desaturase (FAD), found in two genotypes with distinct geographical distribution. FADs are capable of modulating the fluidity of the host’s membrane, a fundamental stress response in living cells. We show that both viral FAD (vFAD) families are Δ9 lipid desaturases, catalyzing the desaturation at carbon 9 in C16 fatty acid chains. In addition, we present a comprehensive fatty acid profiling for marine cyanobacteria, which suggests a unique desaturation pathway of medium- to long-chain fatty acids no longer than C16, in accordance with the vFAD activity. Our findings suggest that cyanophages are capable of fiddling with the infected host’s membranes, possibly leading to increased photoprotection and potentially enhancing viral-encoded photosynthetic proteins, resulting in a new viral metabolic network.
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