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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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2
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Shaalan H, Cattan-Tsaushu E, Li K, Avrani S. Sequencing the genomes of LPP-1, the first isolated cyanophage, and its relative LPP-2 reveal different integration mechanisms in closely related phages. HARMFUL ALGAE 2023; 124:102409. [PMID: 37164560 DOI: 10.1016/j.hal.2023.102409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Revised: 02/16/2023] [Accepted: 02/18/2023] [Indexed: 05/12/2023]
Abstract
In the early 1960s, the first cyanophage was isolated. The description of this phage, named LPP-1, led to the extensive investigation of various cyanophages and to the study of their interactions with their cyanobacterial hosts towards controlling blooms. Here, the genomes of LPP-1 and its putative relative, LPP-2 were sequenced. Sequencing these genomes revealed that LPP-1 and LPP-2 are members of a group of short-tailed cyanophages, which are distantly related to the T7-like cyanophages. Most of the phages in this group have the ability to lysogenize their hosts. Their ability to switch between lytic and lysogenic infection may explain the formation of cyanobacterial blooms despite the persistence of their phages. This lysogenic capacity of the LPP-1-like phages occurs despite the lack of an obvious integrase gene within their genomes. Interestingly, we show that LPP-2 integrates into the host genome through an integration site in high proximity to a recombination endonuclease that may have integrase activity. Further understanding of cyanobacterial-phage relationships may provide insight into their population dynamics and suggest novel approaches for control of destructive cyanobacterial blooms.
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Affiliation(s)
- Hanaa Shaalan
- Department of Evolutionary and Environmental Biology and The Institute of Evolution, University of Haifa, Haifa, Israel
| | - Eti Cattan-Tsaushu
- Department of Evolutionary and Environmental Biology and The Institute of Evolution, University of Haifa, Haifa, Israel
| | - Ke Li
- Department of Evolutionary and Environmental Biology and The Institute of Evolution, University of Haifa, Haifa, Israel
| | - Sarit Avrani
- Department of Evolutionary and Environmental Biology and The Institute of Evolution, University of Haifa, Haifa, Israel.
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Zhu X, Li Z, Tong Y, Chen L, Sun T, Zhang W. From natural to artificial cyanophages: Current progress and application prospects. ENVIRONMENTAL RESEARCH 2023; 223:115428. [PMID: 36746205 DOI: 10.1016/j.envres.2023.115428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Revised: 02/01/2023] [Accepted: 02/03/2023] [Indexed: 06/18/2023]
Abstract
The over proliferation of harmful cyanobacteria and their cyanotoxins resulted in damaged aquatic ecosystem, polluted drinking water and threatened human health. Cyanophages are a kind of viruses that exclusively infect cyanobacteria, which is considered as a potential strategy to deal with cyanobacterial blooms. Nevertheless, the infecting host range and/or lysis efficiency of natural cyanophages is limited, rising the necessity of constructing non-natural cyanophages via artificial modification, design and synthesis to expand their host range and/or efficiency. The paper firstly reviewed representative cyanophages such as P60 with a short latent period of 1.5 h and S-CBS1 having a burst size up to 200 PFU/cell. To explore the in-silico design principles, we critically summarized the interactions between cyanophages and the hosts, indicating modifying the recognized receptors, enhancing the adsorption ability, changing the lysogeny and excluding the defense of hosts are important for artificial cyanophages. The research progress of synthesizing artificial cyanophages were summarized subsequently, raising the importance of developing genetic manipulation technologies and their rescue strategies in the future. Meanwhile, Large-scale preparation of cyanophages for bloom control is a big challenge. The application prospects of artificial cyanophages besides cyanobacteria bloom control like adaptive evolution and phage therapy were discussed at last. The review will promote the design, synthesis and application of cyanophages for cyanobacteria blooms, which may provide new insights for the related water pollution control and ensuring hydrosphere security.
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Affiliation(s)
- Xiaofei Zhu
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, 300072, PR China; Frontier Science Center for Synthetic Biology & Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, 300072, PR China
| | - Zipeng Li
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Yindong Tong
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Lei Chen
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, 300072, PR China; Frontier Science Center for Synthetic Biology & Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, 300072, PR China.
| | - Tao Sun
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, 300072, PR China; Frontier Science Center for Synthetic Biology & Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, 300072, PR China; Center for Biosafety Research and Strategy, Tianjin University, Tianjin, 300072, PR China.
| | - Weiwen Zhang
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, 300072, PR China; Frontier Science Center for Synthetic Biology & Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, 300072, PR China; Center for Biosafety Research and Strategy, Tianjin University, Tianjin, 300072, PR China
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4
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Zhou Q, Li D, Lin W, Pan L, Qian M, Wang F, Cai R, Qu C, Tong Y. Genomic Analysis of a New Freshwater Cyanophage Lbo240-yong1 Suggests a New Taxonomic Family of Bacteriophages. Viruses 2023; 15:v15040831. [PMID: 37112811 PMCID: PMC10140849 DOI: 10.3390/v15040831] [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: 03/02/2023] [Revised: 03/18/2023] [Accepted: 03/20/2023] [Indexed: 04/29/2023] Open
Abstract
A worldwide ecological issue, cyanobacterial blooms in marine and freshwater have caused enormous losses in both the economy and the environment. Virulent cyanophages-specifically, infecting and lysing cyanobacteria-are key ecological factors involved in limiting the overall extent of the population development of cyanobacteria. Over the past three decades, reports have mainly focused on marine Prochlorococcus and Synechococcus cyanophages, while information on freshwater cyanophages remained largely unknown. In this study, a novel freshwater cyanophage, named Lbo240-yong1, was isolated via the double-layer agar plate method using Leptolyngbya boryana FACHB-240 as a host. Transmission electron microscopy observation illustrated the icosahedral head (50 ± 5 nm in diameter) and short tail (20 ± 5 nm in length) of Lbo240-yong1. Experimental infection against 37 cyanobacterial strains revealed that host-strain-specific Lbo240-yong1 could only lyse FACHB-240. The complete genome of Lbo240-yong1 is a double-stranded DNA of 39,740 bp with a G+C content of 51.99%, and it harbors 44 predicted open reading frames (ORFs). A Lbo240-yong1 ORF shared the highest identity with a gene of a filamentous cyanobacterium, hinting at a gene exchange between the cyanophage and cyanobacteria. A BLASTn search illustrated that Lbo240-yong1 had the highest sequence similarity with the Phormidium cyanophage Pf-WMP4 (89.67% identity, 84% query coverage). In the proteomic tree based on genome-wide sequence similarities, Lbo240-yong1, three Phormidium cyanophages (Pf-WMP4, Pf-WMP3, and PP), one Anabaena phage (A-4L), and one unclassified Arthronema cyanophage (Aa-TR020) formed a monophyletic group that was more deeply diverging than several other families. Pf-WMP4 is the only member of the independent genus Wumpquatrovirus that belongs to the Caudovircetes class. Pf-WMP3 and PP formed the independent genus Wumptrevirus. Anabaena phage A-4L is the only member of the independent Kozyakovvirus genus. The six cyanopodoviruses share similar gene arrangements. Eight core genes were found in them. We propose, here, to set up a new taxonomic family comprising the six freshwater cyanopodoviruses infecting filamentous cyanobacteria. This study enriched the field's knowledge of freshwater cyanophages.
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Affiliation(s)
- Qin Zhou
- Key Laboratory of Marine Biotechnology of Zhejiang Province, School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Dengfeng Li
- Key Laboratory of Marine Biotechnology of Zhejiang Province, School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Wei Lin
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
| | - Linting Pan
- Key Laboratory of Marine Biotechnology of Zhejiang Province, School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Minhua Qian
- Key Laboratory of Marine Biotechnology of Zhejiang Province, School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Fei Wang
- Key Laboratory of Marine Biotechnology of Zhejiang Province, School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Ruqian Cai
- Key Laboratory of Marine Biotechnology of Zhejiang Province, School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Chenxin Qu
- Key Laboratory of Marine Biotechnology of Zhejiang Province, School of Marine Sciences, Ningbo University, Ningbo 315211, China
| | - Yigang Tong
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
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Tychonema sp. BBK16 Characterisation: Lifestyle, Phylogeny and Related Phages. Viruses 2023; 15:v15020442. [PMID: 36851656 PMCID: PMC9958718 DOI: 10.3390/v15020442] [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: 11/03/2022] [Revised: 01/20/2023] [Accepted: 02/03/2023] [Indexed: 02/09/2023] Open
Abstract
Cyanobacterial expansion is harmful to the environment, the ecology of Lake Baikal and the economy of nearby regions and can be dangerous to people and animals. Since 2011, the process of colonisation of the lake with potentially toxic cyanobacteria belonging to the genus Tychonema has continued. An understanding of the mechanism of successful expansion of Tychonema requires scrutiny of biological and genomic features. Tychonema sp. BBK16 was isolated from the coastal zone of Lake Baikal. The morphology of BBK16 biofilm was studied with light, scanning electron and confocal microscopy. The biofilm is based on filaments of cyanobacteria, which are intertwined like felt; there are also dense fascicles of rope-like twisted filaments that impart heterogeneity to the surface of the biofilm. Genome sequencing, intergenomic comparisons and phylogenetic analyses indicated that Tychonema sp. BBK16 represent a new species related to planktic cyanobacterium Tychonema bourrellyi, isolated from Alpine lentic freshwater. Genome investigation revealed the genes possibly responsible for the mixotrophic lifestyle. The presence of CRISPR-Cas and restriction modification defence mechanisms allowed to suggest the existence of phages infecting Tychonema sp. BBK16. Analysis of CRISPR spacers and prophage-derived regions allowed to suggest related cyanophages. Genomic analysis supported the assumption that mobile elements and horizontal transfer participate in shaping the Tychonema sp. BBK16 genome. The findings of the current research suggest that the aptitude of Tychonema sp. BBK16 for biofilm formation and, possibly, its mixotrophic lifestyle provide adaptation advantages that lead to the successful expansion of this cyanobacterium in the Baikal's conditions of freshwater lake environments.
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Du K, Yang F, Zhang JT, Yu RC, Deng Z, Li WF, Chen Y, Li Q, Zhou CZ. Comparative genomic analysis of five freshwater cyanophages and reference-guided metagenomic data mining. MICROBIOME 2022; 10:128. [PMID: 35974417 PMCID: PMC9382816 DOI: 10.1186/s40168-022-01324-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 07/06/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND As important producers using photosynthesis on Earth, cyanobacteria contribute to the oxygenation of atmosphere and the primary production of biosphere. However, due to the eutrophication of urban waterbodies and global warming, uncontrollable growth of cyanobacteria usually leads to the seasonal outbreak of cyanobacterial blooms. Cyanophages, a group of viruses that specifically infect and lyse cyanobacteria, are considered as potential environment-friendly agents to control the harmful blooms. Compared to the marine counterparts, only a few freshwater cyanophages have been isolated and genome sequenced to date, largely limiting their characterizations and applications. RESULTS Here, we isolated five freshwater cyanophages varying in tail morphology, termed Pam1~Pam5, all of which infect the cyanobacterium Pseudanabaena mucicola Chao 1806 that was isolated from the bloom-suffering Lake Chaohu in Anhui, China. The whole-genome sequencing showed that cyanophages Pam1~Pam5 all contain a dsDNA genome, varying in size from 36 to 142 Kb. Phylogenetic analyses suggested that Pam1~Pam5 possess different DNA packaging mechanisms and are evolutionarily distinct from each other. Notably, Pam1 and Pam5 have lysogeny-associated gene clusters, whereas Pam2 possesses 9 punctuated DNA segments identical to the CRISPR spacers in the host genome. Metagenomic data-based calculation of the relative abundance of Pam1~Pam5 at the Nanfei estuary towards the Lake Chaohu revealed that the short-tailed Pam1 and Pam5 account for the majority of the five cyanophages. Moreover, comparative analyses of the reference genomes of Pam1~Pam5 and previously reported cyanophages enabled us to identify three circular and seven linear contigs of virtual freshwater cyanophages from the metagenomic data of the Lake Chaohu. CONCLUSIONS We propose a high-throughput strategy to systematically identify cyanophages based on the currently available metagenomic data and the very limited reference genomes of experimentally isolated cyanophages. This strategy could be applied to mine the complete or partial genomes of unculturable bacteriophages and viruses. Transformation of the synthesized whole genomes of these virtual phages/viruses to proper hosts will enable the rescue of bona fide viral particles and eventually enrich the library of microorganisms that exist on Earth. Video abstract.
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Affiliation(s)
- Kang Du
- School of Life Sciences, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Feng Yang
- School of Life Sciences, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Jun-Tao Zhang
- School of Life Sciences, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Rong-Cheng Yu
- School of Life Sciences, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Ziqing Deng
- BGI-Shenzhen, Shenzhen, 518083, China
- BGI-Beijing, BGI-Shenzhen, Beijing, 100101, China
| | - Wei-Fang Li
- School of Life Sciences, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Yuxing Chen
- School of Life Sciences, University of Science and Technology of China, Hefei, 230027, Anhui, China
| | - Qiong Li
- School of Life Sciences, University of Science and Technology of China, Hefei, 230027, Anhui, China.
| | - Cong-Zhao Zhou
- School of Life Sciences, University of Science and Technology of China, Hefei, 230027, Anhui, China.
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7
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Zhang D, He Y, Gin KYH. Genomic Characterization of a Novel Freshwater Cyanophage Reveals a New Lineage of Cyanopodovirus. Front Microbiol 2022; 12:768868. [PMID: 35095789 PMCID: PMC8790148 DOI: 10.3389/fmicb.2021.768868] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 12/03/2021] [Indexed: 11/13/2022] Open
Abstract
Cyanobacteria are one of the dominant autotrophs in tropical freshwater communities, yet phages infecting them remain poorly characterized. Here we present the characterization of cyanophage S-SRP02, isolated from a tropical freshwater lake in Singapore, which infects Synechococcus sp. Strain SR-C1 isolated from the same lake. S-SRP02 represents a new evolutionary lineage of cyanophage. Out of 47 open reading frames (ORFs), only 20 ORFs share homology with genes encoding proteins of known function. There is lack of auxiliary metabolic genes which was commonly found as core genes in marine cyanopodoviruses. S-SRP02 also harbors unique structural genes highly divergent from other cultured phages. Phylogenetic analysis and viral proteomic tree further demonstrate the divergence of S-SRP02 from other sequenced phage isolates. Nonetheless, S-SRP02 shares synteny with phage genes of uncultured phages obtained from the Mediterranean Sea deep chlorophyll maximum fosmids, indicating the ecological importance of S-SRP02 and its related viruses. This is further supported by metagenomic mapping of environmental viral metagenomic reads onto the S-SRP02 genome.
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Affiliation(s)
- Dong Zhang
- NUS Environmental Research Institute (E2S2-CREATE), National University of Singapore, Singapore, Singapore
| | - Yiliang He
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Karina Yew-Hoong Gin
- NUS Environmental Research Institute (E2S2-CREATE), National University of Singapore, Singapore, Singapore.,Department of Civil and Environmental Engineering, National University of Singapore, Singapore, Singapore
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Host Cyanobacteria Killing by Novel Lytic Cyanophage YongM: A Protein Profiling Analysis. Microorganisms 2022; 10:microorganisms10020257. [PMID: 35208712 PMCID: PMC8875764 DOI: 10.3390/microorganisms10020257] [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: 12/13/2021] [Revised: 01/18/2022] [Accepted: 01/22/2022] [Indexed: 02/01/2023] Open
Abstract
Cyanobacteria are autotrophic prokaryotes that can proliferate robustly in eutrophic waters through photosynthesis. This can lead to outbreaks of lake “water blooms”, which result in water quality reduction and environmental pollution that seriously affect fisheries and aquaculture. The use of cyanophages to control the growth of cyanobacteria is an important strategy to tackle annual cyanobacterial blooms. YongM is a novel lytic cyanophage with a broad host spectrum and high efficiency in killing its host, cyanobacteria FACHB-596. However, changes in cyanophage protein profile during infestation and killing of the host remains unknown. To characterize the proteins and its regulation networks involved in the killing of host cyanobacteria by YongM and evaluate whether this strain YongM could be used as a chassis for further engineering to be a powerful tool in dealing with cyanobacterial blooms, we herein applied 4D label-free high-throughput quantitative proteomics to analyze differentially expressed proteins (DEPs) involved in cyanobacteria host response infected 1 and 8 h with YongM cyanophage. Metabolic pathways, such as photosynthesis, photosynthesis-antennal protein, oxidative phosphorylation, ribosome, carbon fixation, and glycolysis/glycol-isomerization were significantly altered in the infested host, whereas DEPs were associated with the metabolic processes of photosynthesis, precursor metabolites, energy production, and organic nitrogen compounds. Among these DEPs, key proteins involved in YongM-host interaction may be photosystem I P700 chlorophyll-a apolipoprotein, carbon dioxide concentration mechanism protein, cytochrome B, and some YongM infection lysis-related enzymes. Our results provide comprehensive information of protein profiles during the invasion and killing of host cyanobacteria by its cyanophage, which may shed light on future design and manipulation of artificial cyanophages against water blooms.
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Predicting the capsid architecture of phages from metagenomic data. Comput Struct Biotechnol J 2022; 20:721-732. [PMID: 35140890 PMCID: PMC8814770 DOI: 10.1016/j.csbj.2021.12.032] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 12/22/2021] [Accepted: 12/22/2021] [Indexed: 12/29/2022] Open
Abstract
Tailed phages are viruses that infect bacteria and are the most abundant biological entities on Earth. Their ecological, evolutionary, and biogeochemical roles in the planet stem from their genomic diversity. Known tailed phage genomes range from 10 to 735 kilobase pairs thanks to the size variability of the protective protein capsids that store them. However, the role of tailed phage capsids’ diversity in ecosystems is unclear. A fundamental gap is the difficulty of associating genomic information with viral capsids in the environment. To address this problem, here, we introduce a computational approach to predict the capsid architecture (T-number) of tailed phages using the sequence of a single gene—the major capsid protein. This approach relies on an allometric model that relates the genome length and capsid architecture of tailed phages. This allometric model was applied to isolated phage genomes to generate a library that associated major capsid proteins and putative capsid architectures. This library was used to train machine learning methods, and the most computationally scalable model investigated (random forest) was applied to human gut metagenomes. Compared to isolated phages, the analysis of gut data reveals a large abundance of mid-sized (T = 7) capsids, as expected, followed by a relatively large frequency of jumbo-like tailed phage capsids (T ≥ 25) and small capsids (T = 4) that have been under-sampled. We discussed how to increase the method’s accuracy and how to extend the approach to other viruses. The computational pipeline introduced here opens the doors to monitor the ongoing evolution and selection of viral capsids across ecosystems.
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Novel Freshwater Cyanophages Provide New Insights into Evolutionary Relationships between Freshwater and Marine Cyanophages. Microbiol Spectr 2021; 9:e0059321. [PMID: 34585945 PMCID: PMC8557907 DOI: 10.1128/spectrum.00593-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cyanobacteria and cyanophages are present widely in both freshwater and marine environments. However, freshwater cyanophages remain unknown largely due to the small numbers of cyanophage isolates despite their ecological and environmental significance. In this study, we present the characterization of two novel lytic freshwater cyanophages isolated from a tropical inland lake in Singapore, namely, cyanopodovirus S-SRP01 and cyanomyovirus S-SRM01, infecting two different strains of Synechococcus spp. Functional annotation of S-SRP01 and S-SRM01 genomes revealed a high degree of homology with marine cyanophages. Phylogenetic trees of concatenated genes and whole-genome alignment provided further evidence that S-SRP01 is close evolutionarily to marine cyanopodoviruses, while S-SRM01 is evolutionarily close to marine cyanomyoviruses. Few genetic similarities between freshwater and marine cyanophages have been identified in previous studies. The isolation of S-SRP01 and S-SRM01 expand current knowledge on freshwater cyanophages infecting Synechococcus spp. Their high degree of gene sharing provides new insights into the evolutionary relationships between freshwater and marine cyanophages. This relatedness is further supported by the discovery of similar phenomenon from other freshwater viral metagenomes. IMPORTANCE This study expands the current knowledge on freshwater cyanophage isolates and cyanophage genetic diversity, indicating that freshwater and marine cyanophages infecting Synechococcus spp. may share close genetic similarity and evolutionary relationships.
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Petrzik K, Lukavský J, Koloniuk I. Novel Virus on Filamentous Arthronema africanum Cyanobacterium. MICROBIAL ECOLOGY 2021; 81:454-459. [PMID: 32901386 DOI: 10.1007/s00248-020-01599-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 09/03/2020] [Indexed: 06/11/2023]
Abstract
Widely distributed in water environments and in soil, cyanobacteria are hosts of lysogenic or lytic bacterioviruses. A novel, probably lysogenic virus (phage) for which the name Arthronema africanum virus TR020 (Aa-TR020) is proposed, has been isolated from filamentous freshwater cyanobacterium Arthronema africanum. The virus formed turbid plaques on plate culture of A. africanum strain 1980/01 but not on other Arthronema strain and other bacterial species. The genome of Aa-TR020 is linear molecule of dsDNA, 44,805 bp in length with 216 bp long terminal repeats and with G + C content of 46%. Fifty-five genes organized on plus and minus strands were predicted there. The genome size, gene arrangement, and selected protein sequences showed relatedness to Phormidium virus Pf-WMP3 and other viruses known to infect cyanobacteria and classified in the family Podoviridae.
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Affiliation(s)
- Karel Petrzik
- Department of Plant Virology, Institute of Plant Molecular Biology, Biology Centre, Czech Academy of Sciences, Branišovská 31, České Budějovice, Czech Republic.
| | - Jaromír Lukavský
- Centre for Phycology, Institute of Botany, Czech Academy of Sciences, Dukelská 135, Třeboň, Czech Republic
| | - Igor Koloniuk
- Department of Plant Virology, Institute of Plant Molecular Biology, Biology Centre, Czech Academy of Sciences, Branišovská 31, České Budějovice, Czech Republic
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12
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Huang S, Sun Y, Zhang S, Long L. Temporal transcriptomes of a marine cyanopodovirus and its Synechococcus host during infection. Microbiologyopen 2020; 10:e1150. [PMID: 33377630 PMCID: PMC7885011 DOI: 10.1002/mbo3.1150] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 12/01/2020] [Accepted: 12/07/2020] [Indexed: 12/24/2022] Open
Abstract
Marine picocyanobacteria belonging to genera Synechococcus and Prochlorococcus are genetically diverged and distributed into distinct biogeographical patterns, and both are infected by genetically closely related cyanopodoviruses. Previous studies have not fully explored whether the two virus–host systems share similar gene expression patterns during infection. Whole‐genome expression dynamics of T7‐like cyanopodovirus P‐SSP7 and its host Prochlorococcus strain MED4 have already been reported. Here, we conducted genomic and transcriptomic analyses on T7‐like cyanopodovirus S‐SBP1 during its infection on Synechococcus strain WH7803. S‐SBP1 has a latent period of 8 h and phage DNA production of 30 copies per cell. In terms of whole‐genome phylogenetic relationships and average nucleotide identity, S‐SBP1 was most similar to cyanopodovirus S‐RIP2, which also infects Synechococcus WH7803. Three hypervariable genomic islands were identified when comparing the genomes of S‐SBP1 and S‐RIP2. Single nucleotide variants were also observed in three S‐SBP1 genes, which were located within the island regions. Based on RNA‐seq analysis, S‐SBP1 genes clustered into three temporal expression classes, whose gene content was similar to that of P‐SSP7. Thirty‐two host genes were upregulated during phage infection, including those involved in carbon metabolism, ribosome components, and stress response. These upregulated genes were similar to those upregulated by Prochlorococcus MED4 in response to infection by P‐SSP7. Our study demonstrates a programmed temporal expression pattern of cyanopodoviruses and hosts during infection.
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Affiliation(s)
- Sijun Huang
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - Yingting Sun
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - Si Zhang
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
| | - Lijuan Long
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China
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13
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Morimoto D, Šulčius S, Yoshida T. Viruses of freshwater bloom-forming cyanobacteria: genomic features, infection strategies and coexistence with the host. ENVIRONMENTAL MICROBIOLOGY REPORTS 2020; 12:486-502. [PMID: 32754956 DOI: 10.1111/1758-2229.12872] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 07/28/2020] [Accepted: 07/31/2020] [Indexed: 06/11/2023]
Abstract
Freshwater bloom-forming cyanobacteria densely grow in the aquatic environments, leading to an increase in the viral-contact rate. They possess numerous antiviral genes, as well as cell differentiation- and physiological performance-related genes, owing to genome expansion. Their genomic features and unique lifestyles suggest that they coexist with cyanoviruses in ways different from marine cyanobacteria. Furthermore, genome contents of isolated freshwater bloom-forming cyanobacterial viruses have little in common with those of marine cyanoviruses studied to date. They lack the marine cyanoviral hallmark genes that sustain photosynthetic activity and redirect host metabolism to viral reproduction; therefore, they are predicted to share metabolisms and precursor pools with host cyanobacteria to ensure efficient viral reproduction and avoid nutrient deficiencies and antiviral response. Additionally, cyanovirus-cyanobacteria coexistence strategies may change as bloom density increases. Diverse genotypic populations of cyanoviruses and hosts coexist and fluctuate under high viral-contact rate conditions, leading to their rapid coevolution through antiviral responses. The ancestral and newly evolved genotypes coexist, thereby expanding the diversity levels of host and viral populations. Bottleneck events occurring due to season-related decreases in bloom-forming species abundance provide each genotype within cyanobacterial population an equal chance to increase in prevalence during the next bloom and enhance further diversification.
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Affiliation(s)
- Daichi Morimoto
- Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Sigitas Šulčius
- Laboratory of Algology and Microbial Ecology, Nature Research Centre, Akademijos 2, Vilnius, 08412, Lithuania
| | - Takashi Yoshida
- Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake, Sakyo-ku, Kyoto, 606-8502, Japan
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14
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Yang F, Jin H, Wang XQ, Li Q, Zhang JT, Cui N, Jiang YL, Chen Y, Wu QF, Zhou CZ, Li WF. Genomic Analysis of Mic1 Reveals a Novel Freshwater Long-Tailed Cyanophage. Front Microbiol 2020; 11:484. [PMID: 32322241 PMCID: PMC7156551 DOI: 10.3389/fmicb.2020.00484] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Accepted: 03/05/2020] [Indexed: 12/12/2022] Open
Abstract
Lake Chaohu, one of the five largest freshwater lakes in China, has been suffering from severe cyanobacterial blooms in the summer for many years. Cyanophages, the viruses that specifically infect cyanobacteria, play a key role in modulating cyanobacterial population, and thus regulate the emergence and decline of cyanobacterial blooms. Here we report a long-tailed cyanophage isolated from Lake Chaohu, termed Mic1, which specifically infects the cyanobacterium Microcystis aeruginosa. Mic1 has an icosahedral head of 88 nm in diameter and a long flexible tail of 400 nm. It possesses a circular genome of 92,627 bp, which contains 98 putative open reading frames. Genome sequence analysis enabled us to define a novel terminase large subunit that consists of two types of intein, indicating that the genome packaging of Mic1 is under fine control via posttranslational maturation of the terminase. Moreover, phylogenetic analysis suggested Mic1 and mitochondria share a common evolutionary origin of DNA polymerase γ gene. All together, these findings provided a start-point for investigating the co-evolution of cyanophages and its cyanobacterial hosts.
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Affiliation(s)
- Feng Yang
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Hua Jin
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Xiao-Qian Wang
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Qiong Li
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Jun-Tao Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Ning Cui
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Yong-Liang Jiang
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Yuxing Chen
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Qing-Fa Wu
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Cong-Zhao Zhou
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Wei-Fang Li
- Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, China
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15
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Ruiz-Perez CA, Tsementzi D, Hatt JK, Sullivan MB, Konstantinidis KT. Prevalence of viral photosynthesis genes along a freshwater to saltwater transect in Southeast USA. ENVIRONMENTAL MICROBIOLOGY REPORTS 2019; 11:672-689. [PMID: 31265211 DOI: 10.1111/1758-2229.12780] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Accepted: 06/29/2019] [Indexed: 05/28/2023]
Abstract
Bacteriophages encode host-acquired functional genes known as auxiliary metabolic genes (AMGs). Photosynthesis AMGs are commonly found in marine cyanobacteria-infecting Myoviridae and Podoviridae cyanophages, but their ecology remains understudied in freshwater environments. To advance knowledge of this issue, we analysed viral metagenomes collected in the summertime for four years from five lakes and two estuarine locations interconnected by the Chattahoochee River, Southeast USA. Sequences representing ten different AMGs were recovered and found to be prevalent in all sites. Most freshwater AMGs were 10-fold less abundant than estuarine and marine AMGs and were encoded by novel Myoviridae and Podoviridae cyanophage genera. Notably, several of the corresponding viral genomes showed endemism to a specific province along the river. This translated into psbA gene phylogenetic clustering patterns that matched a marine vs. freshwater origin indicating that psbA may serve as a robust classification and source-tracking biomarker. Genomes classified in a novel viral lineage represented by isolate S-EIVl contained psbA, which is unprecedented for this lineage. Collectively, our findings indicated that the acquisition of photosynthesis AMGs is a widespread strategy used by cyanophages in aquatic ecosystems, and further indicated the existence of viral provinces in which certain viral species and/or genotypes are locally abundant.
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Affiliation(s)
- Carlos A Ruiz-Perez
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, USA
| | - Despina Tsementzi
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Janet K Hatt
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Matthew B Sullivan
- Departments of Microbiology and Civil, Environmental and Geodetic Engineering, Ohio State University, Columbus, OH, USA
| | - Konstantinos T Konstantinidis
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA, USA
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, USA
- Center for Bioinformatics and Computational Genomics, Georgia Institute of Technology, Atlanta, GA, USA
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16
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Cheng K, Frenken T, Brussaard CPD, Van de Waal DB. Cyanophage Propagation in the Freshwater Cyanobacterium Phormidium Is Constrained by Phosphorus Limitation and Enhanced by Elevated pCO 2. Front Microbiol 2019; 10:617. [PMID: 30984143 PMCID: PMC6449453 DOI: 10.3389/fmicb.2019.00617] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 03/11/2019] [Indexed: 11/17/2022] Open
Abstract
Intensification of human activities has led to changes in the availabilities of CO2 and nutrients in freshwater ecosystems, which may greatly alter the physiological status of phytoplankton. Viruses require hosts for their reproduction and shifts in phytoplankton host physiology through global environmental change may thus affect viral infections as well. Various studies have investigated the impacts of single environmental factors on phytoplankton virus propagation, yet little is known about the impacts of multiple factors, particularly in freshwater systems. We therefore tested the combined effects of phosphorus limitation and elevated pCO2 on the propagation of a cyanophage infecting a freshwater cyanobacterium. To this end, we cultured Phormidium in P-limited chemostats under ambient (400 μatm) and elevated (800 μatm) pCO2 at growth rates of 0.6, 0.3, and 0.05 d-1. Host C:P ratios generally increased with strengthened P-limitation and with elevated pCO2. Upon host steady state conditions, virus growth characteristics were obtained in separate infection assays where hosts were infected by the double-stranded DNA cyanophage PP. Severe P-limitation (host growth 0.05 d-1) led to a 85% decrease in cyanophage production rate and a 73% decrease in burst size compared to the 0.6 d-1 grown P-limited cultures. Elevated pCO2 induced a 96% increase in cyanophage production rate and a 57% increase in burst size, as well as an 85% shorter latent period as compared to ambient pCO2 at the different host growth rates. In addition, elevated pCO2 caused a decrease in the plaquing efficiency and an increase in the abortion percentage for the 0.05 d-1 P-limited treatment, while the plaquing efficiency increased for the 0.6 d-1 P-limited cultures. Together, our results demonstrate interactive effects of elevated pCO2 and P-limitation on cyanophage propagation, and show that viral propagation is generally constrained by P-limitation but enhanced with elevated pCO2. Our findings indicate that global change will likely have a severe impact on virus growth characteristics and thereby on the control of cyanobacterial hosts in freshwater ecosystems.
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Affiliation(s)
- Kai Cheng
- Hubei Key Laboratory of Ecological Restoration for River-Lakes and Algal Utilization, College of Resources and Environmental Engineering, Hubei University of Technology, Wuhan, China.,Department of Aquatic Ecology, Netherlands Institute of Ecology, Wageningen, Netherlands
| | - Thijs Frenken
- Department of Aquatic Ecology, Netherlands Institute of Ecology, Wageningen, Netherlands
| | - Corina P D Brussaard
- Department of Marine Microbiology and Biogeochemistry, Royal Netherlands Institute for Sea Research and University of Utrecht, Texel, Netherlands
| | - Dedmer B Van de Waal
- Department of Aquatic Ecology, Netherlands Institute of Ecology, Wageningen, Netherlands
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17
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Genomic Characterization of Cyanophage vB_AphaS-CL131 Infecting Filamentous Diazotrophic Cyanobacterium Aphanizomenon flos-aquae Reveals Novel Insights into Virus-Bacterium Interactions. Appl Environ Microbiol 2018; 85:AEM.01311-18. [PMID: 30367000 PMCID: PMC6293099 DOI: 10.1128/aem.01311-18] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2018] [Accepted: 10/07/2018] [Indexed: 12/29/2022] Open
Abstract
While filamentous cyanobacteria play a crucial role in food web dynamics and biogeochemical cycling of many aquatic ecosystems around the globe, the knowledge regarding the phages infecting them is limited. Here, we describe the complete genome of the virulent cyanophage vB_AphaS-CL131 (here, CL 131), a Siphoviridae phage that infects the filamentous diazotrophic bloom-forming cyanobacterium Aphanizomenon flos-aquae in the brackish Baltic Sea. CL 131 features a 112,793-bp double-stranded DNA (dsDNA) genome encompassing 149 putative open reading frames (ORFs), of which the majority (86%) lack sequence homology to genes with known functions in other bacteriophages or bacteria. Phylogenetic analysis revealed that CL 131 possibly represents a new evolutionary lineage within the group of cyanophages infecting filamentous cyanobacteria, which form a separate cluster from phages infecting unicellular cyanobacteria. CL 131 encodes a putative type V-U2 CRISPR-Cas system with one spacer (out of 10) targeting a DNA primase pseudogene in a cyanobacterium and a putative type II toxin-antitoxin system, consisting of a GNAT family N-acetyltransferase and a protein of unknown function containing the PRK09726 domain (characteristic of HipB antitoxins). Comparison of CL 131 proteins to reads from Baltic Sea and other available fresh- and brackish-water metagenomes and analysis of CRISPR-Cas arrays in publicly available A. flos-aquae genomes demonstrated that phages similar to CL 131 are present and dynamic in the Baltic Sea and share a common history with their hosts dating back at least several decades. In addition, different CRISPR-Cas systems within individual A. flos-aquae genomes targeted several sequences in the CL 131 genome, including genes related to virion structure and morphogenesis. Altogether, these findings revealed new genomic information for exploring viral diversity and provide a model system for investigation of virus-host interactions in filamentous cyanobacteria.IMPORTANCE The genomic characterization of novel cyanophage vB_AphaS-CL131 and the analysis of its genomic features in the context of other viruses, metagenomic data, and host CRISPR-Cas systems contribute toward a better understanding of aquatic viral diversity and distribution in general and of brackish-water cyanophages infecting filamentous diazotrophic cyanobacteria in the Baltic Sea in particular. The results of this study revealed previously undescribed features of cyanophage genomes (e.g., self-excising intein-containing putative dCTP deaminase and putative cyanophage-encoded CRISPR-Cas and toxin-antitoxin systems) and can therefore be used to predict potential interactions between bloom-forming cyanobacteria and their cyanophages.
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18
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Guajardo-Leiva S, Pedrós-Alió C, Salgado O, Pinto F, Díez B. Active Crossfire Between Cyanobacteria and Cyanophages in Phototrophic Mat Communities Within Hot Springs. Front Microbiol 2018; 9:2039. [PMID: 30233525 PMCID: PMC6129581 DOI: 10.3389/fmicb.2018.02039] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 08/13/2018] [Indexed: 01/16/2023] Open
Abstract
Cyanophages are viruses with a wide distribution in aquatic ecosystems, that specifically infect Cyanobacteria. These viruses can be readily isolated from marine and fresh waters environments; however, their presence in cosmopolitan thermophilic phototrophic mats remains largely unknown. This study investigates the morphological diversity (TEM), taxonomic composition (metagenomics), and active infectivity (metatranscriptomics) of viral communities over a thermal gradient in hot spring phototrophic mats from Northern Patagonia (Chile). The mats were dominated (up to 53%) by cosmopolitan thermophilic filamentous true-branching cyanobacteria from the genus Mastigocladus, the associated viral community was predominantly composed of Caudovirales (70%), with most of the active infections driven by cyanophages (up to 90% of Caudovirales transcripts). Metagenomic assembly lead to the first full genome description of a T7-like Thermophilic Cyanophage recovered from a hot spring (Porcelana Hot Spring, Chile), with a temperature of 58°C (TC-CHP58). This could potentially represent a world-wide thermophilic lineage of podoviruses that infect cyanobacteria. In the hot spring, TC-CHP58 was active over a temperature gradient from 48 to 66°C, showing a high population variability represented by 1979 single nucleotide variants (SNVs). TC-CHP58 was associated to the Mastigocladus spp. by CRISPR spacers. Marked differences in metagenomic CRISPR loci number and spacers diversity, as well as SNVs, in the TC-CHP58 proto-spacers at different temperatures, reinforce the theory of co-evolution between natural virus populations and cyanobacterial hosts. Considering the importance of cyanobacteria in hot spring biogeochemical cycles, the description of this new cyanopodovirus lineage may have global implications for the functioning of these extreme ecosystems.
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Affiliation(s)
- Sergio Guajardo-Leiva
- Department of Molecular Genetics and Microbiology, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Carlos Pedrós-Alió
- Programa de Biología de Sistemas, Centro Nacional de Biotecnología - Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Oscar Salgado
- Department of Molecular Genetics and Microbiology, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Fabián Pinto
- Department of Molecular Genetics and Microbiology, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Beatriz Díez
- Department of Molecular Genetics and Microbiology, Pontificia Universidad Católica de Chile, Santiago, Chile.,Center for Climate and Resilience Research, Santiago, Chile
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19
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Abstract
Viruses are integral to ecological and evolutionary processes, but we have a poor understanding of what drives variation in key traits across diverse viruses. For lytic viruses, burst size, latent period, and genome size are primary characteristics controlling host-virus dynamics. Here we synthesize data on these traits for 75 strains of phytoplankton viruses, which play an important role in global biogeochemistry. We find that primary traits of the host (genome size, growth rate) explain 40%-50% of variation in burst size and latent period. Specifically, burst size and latent period both exhibit saturating relationships versus the host∶virus genome size ratio, with both traits increasing at low genome size ratios while showing no relationship at high size ratios. In addition, latent period declines as host growth rate increases. We analyze a model of latent period evolution to explore mechanisms that could cause these patterns. The model predicts that burst size may often be set by the host genomic resources available for viral construction, while latent period evolves to permit this maximal burst size, modulated by host metabolic rate. These results suggest that general mechanisms may underlie the evolution of diverse viruses. Future extensions of this work could help explain viral regulation of host populations, viral influence on community structure and diversity, and viral roles in biogeochemical cycles.
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20
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Colombet J, Robin A, Sime-Ngando T. Genotypic, size and morphological diversity of virioplankton in a deep oligomesotrophic freshwater lake (Lac Pavin, France). J Environ Sci (China) 2017; 53:48-59. [PMID: 28372760 DOI: 10.1016/j.jes.2016.05.016] [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: 12/01/2015] [Revised: 05/02/2016] [Accepted: 05/05/2016] [Indexed: 06/07/2023]
Abstract
We examined changes in morphological and genomic diversities of viruses by means of transmission electronic microscopy and pulsed field gel electrophoresis (PFGE) over a nine-month period (April-December 2005) at four different depths in the oligomesotrophic Lac Pavin. We found that the majority of viruses in this lake belonged to the family of Siphoviridae or were untailed, with capsid sizes ranging from 30 to 60nm, and exhibited genome sizes ranging from 15 to 45kb. On average, 12 different genotypes dominated each of the PFGE fingerprints. The highest genomic viral richness was recorded in summer (mean=14 bands per PFGE fingerprint) and in the epilimnion (mean=13 bands per PFGE fingerprint). Among the physico-chemical and biological variables considered, the availability of the hosts appeared to be the main factor regulating the variations in the viral diversity.
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Affiliation(s)
- Jonathan Colombet
- Laboratory Microorganisms: Genome and Environment, Clermont University Blaise Pascal, UMR CNRS 6023, 24 avenue des Landais, BP 80026, F-63171 Aubière, France.
| | - Agnès Robin
- CIRAD, UMR Eco&Sols, 2 place Viala, 34060 Montpellier Cedex 1, France
| | - Télesphore Sime-Ngando
- Laboratory Microorganisms: Genome and Environment, Clermont University Blaise Pascal, UMR CNRS 6023, 24 avenue des Landais, BP 80026, F-63171 Aubière, France
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21
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Gao EB, Huang Y, Ning D. Metabolic Genes within Cyanophage Genomes: Implications for Diversity and Evolution. Genes (Basel) 2016; 7:genes7100080. [PMID: 27690109 PMCID: PMC5083919 DOI: 10.3390/genes7100080] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 08/30/2016] [Accepted: 09/15/2016] [Indexed: 11/16/2022] Open
Abstract
Cyanophages, a group of viruses specifically infecting cyanobacteria, are genetically diverse and extensively abundant in water environments. As a result of selective pressure, cyanophages often acquire a range of metabolic genes from host genomes. The host-derived genes make a significant contribution to the ecological success of cyanophages. In this review, we summarize the host-derived metabolic genes, as well as their origin and roles in cyanophage evolution and important host metabolic pathways, such as the light-dependent reactions of photosynthesis, the pentose phosphate pathway, nutrient acquisition and nucleotide biosynthesis. We also discuss the suitability of the host-derived metabolic genes as potential diagnostic markers for the detection of genetic diversity of cyanophages in natural environments.
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Affiliation(s)
- E-Bin Gao
- School of The Environment and Safety Engineering, Jiangsu University, No. 301, Xuefu Road, Zhenjiang 212013, Jiangsu Province, China.
| | - Youhua Huang
- Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, No. 164, Xingangxi Road, Haizhu District, Guangzhou 5103401, Guangdong Province, China.
| | - Degang Ning
- ACS Key Laboratory of Algae Biology, Institute of Hydrobiology, Chinese Academy of Sciences, No. 7, Donghu South Road, Wuchang District, Wuhan 430072, Hubei Province, China.
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22
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Viruses Infecting a Freshwater Filamentous Cyanobacterium (Nostoc sp.) Encode a Functional CRISPR Array and a Proteobacterial DNA Polymerase B. mBio 2016; 7:mBio.00667-16. [PMID: 27302758 PMCID: PMC4916379 DOI: 10.1128/mbio.00667-16] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
UNLABELLED Here we present the first genomic characterization of viruses infecting Nostoc, a genus of ecologically important cyanobacteria that are widespread in freshwater. Cyanophages A-1 and N-1 were isolated in the 1970s and infect Nostoc sp. strain PCC 7210 but remained genomically uncharacterized. Their 68,304- and 64,960-bp genomes are strikingly different from those of other sequenced cyanophages. Many putative genes that code for proteins with known functions are similar to those found in filamentous cyanobacteria, showing a long evolutionary history in their host. Cyanophage N-1 encodes a CRISPR array that is transcribed during infection and is similar to the DR5 family of CRISPRs commonly found in cyanobacteria. The presence of a host-related CRISPR array in a cyanophage suggests that the phage can transfer the CRISPR among related cyanobacteria and thereby provide resistance to infection with competing phages. Both viruses also encode a distinct DNA polymerase B that is closely related to those found in plasmids of Cyanothece sp. strain PCC 7424, Nostoc sp. strain PCC 7120, and Anabaena variabilis ATCC 29413. These polymerases form a distinct evolutionary group that is more closely related to DNA polymerases of proteobacteria than to those of other viruses. This suggests that the polymerase was acquired from a proteobacterium by an ancestral virus and transferred to the cyanobacterial plasmid. Many other open reading frames are similar to a prophage-like element in the genome of Nostoc sp. strain PCC 7524. The Nostoc cyanophages reveal a history of gene transfers between filamentous cyanobacteria and their viruses that have helped to forge the evolutionary trajectory of this previously unrecognized group of phages. IMPORTANCE Filamentous cyanobacteria belonging to the genus Nostoc are widespread and ecologically important in freshwater, yet little is known about the genomic content of their viruses. Here we report the first genomic analysis of cyanophages infecting filamentous freshwater cyanobacteria, revealing that their gene content is unlike that of other cyanophages. In addition to sharing many gene homologues with freshwater cyanobacteria, cyanophage N-1 encodes a CRISPR array and expresses it upon infection. Also, both viruses contain a DNA polymerase B-encoding gene with high similarity to genes found in proteobacterial plasmids of filamentous cyanobacteria. The observation that phages can acquire CRISPRs from their hosts suggests that phages can also move them among hosts, thereby conferring resistance to competing phages. The presence in these cyanophages of CRISPR and DNA polymerase B sequences, as well as a suite of other host-related genes, illustrates the long and complex evolutionary history of these viruses and their hosts.
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23
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Lal TM, Sano M, Ransangan J. Genome characterization of a novel vibriophage VpKK5 (Siphoviridae) specific to fish pathogenic strain of Vibrio parahaemolyticus. J Basic Microbiol 2016; 56:872-88. [PMID: 26960780 DOI: 10.1002/jobm.201500611] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 02/19/2016] [Indexed: 12/25/2022]
Abstract
Vibrio parahaemolyticus has long been known pathogenic to shrimp but only recently it is also reported pathogenic to tropical cultured marine finfish. Traditionally, bacterial diseases in aquaculture are often treated using synthetic antibiotics but concern due to side effects of these chemicals is elevating hence, new control strategies which are both environmental and consumer friendly, are urgently needed. One promising control strategy is the bacteriophage therapy. In this study, we report the isolation and characterization of a novel vibriophage (VpKK5), belonging to the family Siphoviridae that was specific and capable of complete lysing the fish pathogenic strain of V. parahaemolyticus. The VpKK5 exhibited short eclipse and latent periods of 24 and 36 min, respectively, but with a large burst size of 180 pfu/cell. The genome analysis revealed that the VpKK5 is a novel bacteriophage with the estimated genome size of 56,637 bp and has 53.1% G + C content. The vibriophage has about 80 predicted open reading frames consisted of 37 complete coding sequences which did not match to any protein databases. The analysis also found no lysogeny and virulence genes in the genome of VpKK5. With such genome features, we suspected the vibriophage is novel and could be explored for phage therapy against fish pathogenic strains of V. parahaemolyticus in the near future.
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Affiliation(s)
- Tamrin M Lal
- Microbiology and Fish Disease Laboratory, Borneo Marine Research Institute, Universiti Malaysia Sabah, Jalan UMS, Kota Kinabalu, Sabah, Malaysia
| | - Motohiko Sano
- Laboratory of Fish Pathology, Department of Marine Biosciences, Tokyo University of Marine Science and Technology, Minato-ku, Tokyo, Japan
| | - Julian Ransangan
- Microbiology and Fish Disease Laboratory, Borneo Marine Research Institute, Universiti Malaysia Sabah, Jalan UMS, Kota Kinabalu, Sabah, Malaysia
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24
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Mankiewicz-Boczek J, Jaskulska A, Pawełczyk J, Gągała I, Serwecińska L, Dziadek J. Cyanophages Infection of Microcystis Bloom in Lowland Dam Reservoir of Sulejów, Poland. MICROBIAL ECOLOGY 2016; 71:315-25. [PMID: 26403721 DOI: 10.1007/s00248-015-0677-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 09/10/2015] [Indexed: 05/28/2023]
Abstract
An increased incidence of cyanobacterial blooms, which are largely composed of toxigenic cyanobacteria from the Microcystis genus, leads to a disruption of aquatic ecosystems worldwide. Therefore, a better understanding of the impact of environmental parameters on the development and collapse of blooms is important. The objectives of the present study were as follows: (1) to investigate the presence and identity of Microcystis-specific cyanophages capable of cyanobacterial cell lysis in a lowland dam reservoir in Central Europe; (2) to investigate Microcystis sensitivity to phage infections with regard to toxic genotypes; and (3) to identify key abiotic parameters influencing phage infections during the summer seasons between 2009 and 2013. Sequencing analysis of selected g91 gene amplification products confirmed that the identified cyanophages belonged to the family Myoviridae (95 % homology). Cyanophages and Microcystis hosts, including toxic genotypes, were positively correlated in 4 of the 5 years analyzed (r = 0.67-0.82). The average percentage of infected Microcystis cells varied between 0.1 and 32 %, and no particular sensitivity of the phages to toxigenic genotypes was recorded. The highest number of cyanophages (>10(4) gene copy number per microliter) was observed in the period preceded by the following: an increase of the water retention time, growth of the water temperature, optimum nutrient concentrations, and the predomination of Microcystis bloom.
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Affiliation(s)
- J Mankiewicz-Boczek
- Department of Applied Ecology, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 90-237, Łódź, Poland.
- European Regional Centre for Ecohydrology, Polish Academy of Sciences, Tylna 3, 90-364, Łódź, Poland.
| | - A Jaskulska
- Department of Applied Ecology, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 90-237, Łódź, Poland
- European Regional Centre for Ecohydrology, Polish Academy of Sciences, Tylna 3, 90-364, Łódź, Poland
| | - J Pawełczyk
- Institute for Medical Biology, Polish Academy of Sciences, Lodowa 106, 93-232, Łódź, Poland
| | - I Gągała
- European Regional Centre for Ecohydrology, Polish Academy of Sciences, Tylna 3, 90-364, Łódź, Poland
| | - L Serwecińska
- European Regional Centre for Ecohydrology, Polish Academy of Sciences, Tylna 3, 90-364, Łódź, Poland
| | - J Dziadek
- Institute for Medical Biology, Polish Academy of Sciences, Lodowa 106, 93-232, Łódź, Poland
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Comparative Genomic and Phylogenomic Analyses Reveal a Conserved Core Genome Shared by Estuarine and Oceanic Cyanopodoviruses. PLoS One 2015; 10:e0142962. [PMID: 26569403 PMCID: PMC4646655 DOI: 10.1371/journal.pone.0142962] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 10/29/2015] [Indexed: 11/19/2022] Open
Abstract
Podoviruses are among the major viral groups that infect marine picocyanobacteria Prochlorococcus and Synechococcus. Here, we reported the genome sequences of five Synechococcus podoviruses isolated from the estuarine environment, and performed comparative genomic and phylogenomic analyses based on a total of 20 cyanopodovirus genomes. The genomes of all the known marine cyanopodoviruses are highly syntenic. A pan-genome of 349 clustered orthologous groups was determined, among which 15 were core genes. These core genes make up nearly half of each genome in length, reflecting the high level of genome conservation among this cyanophage type. The whole genome phylogenies based on concatenated core genes and gene content were highly consistent and confirmed the separation of two discrete marine cyanopodovirus clusters MPP-A and MPP-B. The genomes within cluster MPP-B grouped into subclusters mainly corresponding to Prochlorococcus or Synechococcus host types. Auxiliary metabolic genes tend to occur in a specific phylogenetic group of these cyanopodoviruses. All the MPP-B phages analyzed here encode the photosynthesis gene psbA, which are absent in all the MPP-A genomes thus far. Interestingly, all the MPP-B and two MPP-A Synechococcus podoviruses encode the thymidylate synthase gene thyX, while at the same genome locus all the MPP-B Prochlorococcus podoviruses encode the transaldolase gene talC. Both genes are hypothesized to have the potential to facilitate the biosynthesis of deoxynucleotide for phage replication. Inheritance of specific functional genes could be important to the evolution and ecological fitness of certain cyanophage genotypes. Our analyses demonstrate that cyanopodoviruses of estuarine and oceanic origins share a conserved core genome and suggest that accessory genes may be related to environmental adaptation.
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Ou T, Liao XY, Gao XC, Xu XD, Zhang QY. Unraveling the genome structure of cyanobacterial podovirus A-4L with long direct terminal repeats. Virus Res 2015; 203:4-9. [PMID: 25836275 DOI: 10.1016/j.virusres.2015.03.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 03/14/2015] [Accepted: 03/20/2015] [Indexed: 10/23/2022]
Abstract
The freshwater cyanobacterial virus (cyanophage) A-4L, a podovirus, can infect the model cyanobacterium Anabaena sp. strain PCC 7120 resulting in a high burst size and forming concentric plaques on its lawns. The complete genome sequence of A-4L was determined by the combination of high-throughput sequencing, terminal transferase-mediated polymerase chain reaction and restriction mapping. It contains 41,750 bp with 810 bp direct terminal repeats and 38 potential open reading frames. As compared with other cyanobacterial podoviruses in diverse ecosystems, the A-4L has the longest terminal repeat and shares similar genome organizations with freshwater members. Furthermore, phylogenetic analysis based on concatenated sequences of eight core proteins indicated that freshwater cyanobacterial podoviruses were clustered together and distinct from marine counterparts, suggesting a clear divergence in the cyanobacterial podovirus lineage between freshwater and marine ecosystems. Our findings uncover the unique genome structure of A-4L which contains long direct terminal repeats, and create the first model system to address knowledge gaps in understanding cyanobacterial virus-host interactions at the molecular level.
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Affiliation(s)
- Tong Ou
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Wuhan 430072, China
| | - Xiang-Yong Liao
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Wuhan 430072, China
| | - Xiao-Chan Gao
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Wuhan 430072, China
| | - Xu-Dong Xu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Wuhan 430072, China
| | - Qi-Ya Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Wuhan 430072, China.
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Chénard C, Chan AM, Vincent WF, Suttle CA. Polar freshwater cyanophage S-EIV1 represents a new widespread evolutionary lineage of phages. ISME JOURNAL 2015; 9:2046-58. [PMID: 25822482 DOI: 10.1038/ismej.2015.24] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 01/02/2015] [Accepted: 01/06/2015] [Indexed: 11/09/2022]
Abstract
Cyanobacteria are often the dominant phototrophs in polar freshwater communities; yet, the phages that infect them remain unknown. Here, we present a genomic and morphological characterization of cyanophage S-EIV1 that was isolated from freshwaters on Ellesmere Island (Nunavut, High Arctic Canada), and which infects the polar Synechococcus sp., strain PCCC-A2c. S-EIV1 represents a newly discovered evolutionary lineage of bacteriophages whose representatives are widespread in aquatic systems. Among the 130 predicted open reading frames (ORFs) there is no recognizable similarity to genes that encode structural proteins other than the large terminase subunit and a distant viral morphogenesis protein, indicating that the genes encoding the structural proteins of S-EIV1 are distinct from other viruses. As well, only 19 predicted coding sequences on the 79 178 bp circularly permuted genome have homology with genes encoding proteins of known function. Although S-EIV1 is divergent from other sequenced phage isolates, it shares synteny with phage genes captured on a fosmid from the deep-chlorophyll maximum in the Mediterranean Sea, as well as with an incision element in the genome of Anabaena variabilis (ATCC 29413). Sequence recruitment of metagenomic data indicates that S-EIV1-like viruses are cosmopolitan and abundant in a wide range of aquatic systems, suggesting they have an important ecological role.
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Affiliation(s)
- C Chénard
- Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - A M Chan
- Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - W F Vincent
- Département de Biologie and Centre d'études nordiques (CEN), Laval University, Quebec City, Quebec, Canada
| | - C A Suttle
- 1] Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia, Canada [2] Departments of Botany, and Microbiology & Immunology, University of British Columbia, Vancouver, British Columbia, Canada [3] Canadian Institute for Advanced Research, Toronto, Ontario, Canada
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Zhong X, Ram ASP, Colombet J, Jacquet S. Variations in abundance, genome size, morphology, and functional role of the virioplankton in Lakes Annecy and Bourget over a 1-year period. MICROBIAL ECOLOGY 2014; 67:66-82. [PMID: 24253662 DOI: 10.1007/s00248-013-0320-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Accepted: 10/24/2013] [Indexed: 06/02/2023]
Abstract
We sampled the surface waters (2-50 m) of two deep peri-alpine lakes over a 1-year period in order to examine (1) the abundance, vertical distribution, genome size, and morphology structures of the virioplankton; (2) the virus-mediated bacterial mortality; and (3) the specific genome size range of double-stranded DNA (dsDNA) phytoplankton viruses. Virus-like particle (VLP) concentrations varied between 4.16 × 10(7) (January) and 2.08 × 10(8) part mL(-1) (May) in Lake Bourget and between 2.7 × 10(7) (June) and 8.39 × 10(7) part mL(-1) (November) in Lake Annecy. Our flow cytometry analysis revealed at least three viral groups (referred to as virus-like particles 1, 2, and 3) that exhibited distinctive dynamics suggestive of different host types. Phage-induced bacterial mortality varied between 6.1% (June) and 33.2% (October) in Lake Bourget and between 7.4% (June) and 52.6% (November) in Lake Annecy, suggesting that viral lysis may be a key cause of mortality of the bacterioplankton. Virioplankton genome size ranged from 27 to 486 kb in Lake Bourget, while it reached 620 kb in Lake Annecy for which larger genome sizes were recorded. Our analysis of pulsed field gel electrophoresis bands using different PCR primers targeting both cyanophages and algal viruses showed that (1) dsDNA viruses infecting phytoplankton may range from 65 to 486 kb, and (2) both cyanophage and algal "diversity" were higher in Lake Annecy. Lakes Annecy and Bourget also differed regarding the proportions of both viral families (with the dominance of myoviruses vs. podoviruses) and infected bacterial morphotypes (short rods vs. elongated rods), in each of these lakes, respectively. Overall, our results reveal that (1) viruses displayed distinct temporal and vertical distribution, dynamics, community structure in terms of genome size and morphology, and viral activity in the two lakes; (2) the Myoviridae seemed to be the main cause of bacterial mortality in both lakes and this group seemed to be related to VLP2; and (3) phytoplankton viruses may have a broader range of genome size than previously thought. This study adds to growing evidence that viruses are diverse and play a significant role in freshwater microbial dynamics and more globally lake functioning. It highlights the importance of further considering this biological compartment for a better understanding of plankton ecology in peri-alpine lakes.
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Affiliation(s)
- Xu Zhong
- INRA, UMR 042 CARRTEL, 75 Avenue de Corzent, 74203, Thonon-les-Bains cx, France
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29
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Xia H, Li T, Deng F, Hu Z. Freshwater cyanophages. Virol Sin 2013; 28:253-9. [PMID: 24132756 DOI: 10.1007/s12250-013-3370-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2013] [Accepted: 09/25/2013] [Indexed: 12/01/2022] Open
Abstract
Cyanophages are double-stranded DNA viruses that infect cyanobacteria, and they can be found in both freshwater and marine environments. They have a complex pattern of host ranges and play important roles in controlling cyanobacteria population. Unlike marine cyanophages, for which there have been a number of recent investigations, very little attention has been paid to freshwater cyanophages. This review summarizes the taxonomy and morphology, host range, distribution, seasonal dynamics, and complete genomes of freshwater cyanophages, as well as diagnostic markers that can be used to identify them.
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Affiliation(s)
- Han Xia
- State Key Laboratory of Virology, Virus Resource and Bioinformatics Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
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30
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Zhou Y, Lin J, Li N, Hu Z, Deng F. Characterization and genomic analysis of a plaque purified strain of cyanophage PP. Virol Sin 2013; 28:272-9. [PMID: 24132757 DOI: 10.1007/s12250-013-3363-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Accepted: 09/23/2013] [Indexed: 11/24/2022] Open
Abstract
Cyanophages are ubiquitous and essential components of the aquatic environment and play an important role in the termination of algal blooms. As such, they have attracted widespread interest. PP was the first isolated cyanophage in China, which infects Plectonema boryanum and Phormidium foveolarum. In this study, this cyanophage was purified three times by a double-agar overlay plaque assay and characterized. Its genome was extracted, totally sequenced and analyzed. Electron microscopy revealed a particle with an icosahedral head connected to a short stubby tail. Bioassays showed that PP was quite virulent. The genome of PP is a 42,480 base pair (bp), linear, double-stranded DNA molecule with 222 bp terminal repeats. It has high similarity with the known Pf-WMP3 sequence. It contains 41 open reading frames (ORFs), 17 of which were annotated. Intriguingly, the genome can be divided into two completely different parts, which differ both in orientation and function.
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Affiliation(s)
- Yiran Zhou
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, 430071, China
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31
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Cai F, Axen SD, Kerfeld CA. Evidence for the widespread distribution of CRISPR-Cas system in the Phylum Cyanobacteria. RNA Biol 2013; 10:687-93. [PMID: 23628889 DOI: 10.4161/rna.24571] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Members of the phylum Cyanobacteria inhabit ecologically diverse environments. However, the CRISPR-Cas (clustered regularly interspaced short palindromic repeats, CRISPR associated genes), an extremely adaptable defense system, has not been surveyed in this phylum. We analyzed 126 cyanobacterial genomes and, surprisingly, found CRISPR-Cas in the majority except the marine subclade (Synechococcus and Prochlorococcus), in which cyanophages are a known force shaping their evolution. Multiple observations of CRISPR loci in the absence of cas1/cas2 genes may represent an early stage of losing a CRISPR-Cas locus. Our findings reveal the widespread distribution of their role in the phylum Cyanobacteria and provide a first step to systematically understanding CRISPR-Cas systems in cyanobacteria.
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Affiliation(s)
- Fei Cai
- U.S. Department of Energy-Joint Genome Institute, Walnut Creek, CA, USA
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32
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Labrie SJ, Frois-Moniz K, Osburne MS, Kelly L, Roggensack SE, Sullivan MB, Gearin G, Zeng Q, Fitzgerald M, Henn MR, Chisholm SW. Genomes of marine cyanopodoviruses reveal multiple origins of diversity. Environ Microbiol 2013; 15:1356-76. [DOI: 10.1111/1462-2920.12053] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Accepted: 11/13/2012] [Indexed: 11/30/2022]
Affiliation(s)
- S. J. Labrie
- Department of Civil and Environmental Engineering; Massachusetts Institute of Technology; Cambridge; MA; USA
| | - K. Frois-Moniz
- Department of Civil and Environmental Engineering; Massachusetts Institute of Technology; Cambridge; MA; USA
| | - M. S. Osburne
- Department of Civil and Environmental Engineering; Massachusetts Institute of Technology; Cambridge; MA; USA
| | - L. Kelly
- Department of Civil and Environmental Engineering; Massachusetts Institute of Technology; Cambridge; MA; USA
| | - S. E. Roggensack
- Department of Civil and Environmental Engineering; Massachusetts Institute of Technology; Cambridge; MA; USA
| | - M. B. Sullivan
- Department of Civil and Environmental Engineering; Massachusetts Institute of Technology; Cambridge; MA; USA
| | | | - Q. Zeng
- Broad Institute; Cambridge; MA; USA
| | | | | | - S. W. Chisholm
- Department of Civil and Environmental Engineering; Massachusetts Institute of Technology; Cambridge; MA; USA
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33
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Zhu B, Tabor S, Raytcheva DA, Hernandez A, King JA, Richardson CC. The RNA polymerase of marine cyanophage Syn5. J Biol Chem 2012; 288:3545-52. [PMID: 23258537 DOI: 10.1074/jbc.m112.442350] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A single subunit DNA-dependent RNA polymerase was identified and purified to apparent homogeneity from cyanophage Syn5 that infects the marine cyanobacteria Synechococcus. Syn5 is homologous to bacteriophage T7 that infects Escherichia coli. Using the purified enzyme its promoter has been identified by examining transcription of segments of Syn5 DNA and sequencing the 5'-termini of the transcripts. Only two Syn5 RNAP promoters, having the sequence 5'-ATTGGGCACCCGTAA-3', are found within the Syn5 genome. One promoter is located within the Syn5 RNA polymerase gene and the other is located close to the right genetic end of the genome. The purified enzyme and its promoter have enabled a determination of the requirements for transcription. Unlike the salt-sensitive bacteriophage T7 RNA polymerase, this marine RNA polymerase requires 160 mm potassium for maximal activity. The optimal temperature for Syn5 RNA polymerase is 24 °C, much lower than that for T7 RNA polymerase. Magnesium is required as a cofactor although some activity is observed with ferrous ions. Syn5 RNA polymerase is more efficient in utilizing low concentrations of ribonucleotides than T7 RNA polymerase.
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Affiliation(s)
- Bin Zhu
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.
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I-PfoP3I: a novel nicking HNH homing endonuclease encoded in the group I intron of the DNA polymerase gene in Phormidium foveolarum phage Pf-WMP3. PLoS One 2012; 7:e43738. [PMID: 22952751 PMCID: PMC3428280 DOI: 10.1371/journal.pone.0043738] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Accepted: 07/27/2012] [Indexed: 11/19/2022] Open
Abstract
Homing endonucleases encoded in a group I self-splicing intron in a protein-coding gene in cyanophage genomes have not been reported, apart from some free-standing homing edonucleases. In this study, a nicking DNA endonuclease, I-PfoP3I, encoded in a group IA2 intron in the DNA polymerase gene of a T7-like cyanophage Pf-WMP3, which infects the freshwater cyanobacterium Phormidium foveolarum is described. The Pf-WMP3 intron splices efficiently in vivo and self-splices in vitro simultaneously during transcription. I-PfoP3I belongs to the HNH family with an unconventional C-terminal HNH motif. I-PfoP3I nicks the intron-minus Pf-WMP3 DNA polymerase gene more efficiently than the Pf-WMP4 DNA polymerase gene that lacks any intervening sequence in vitro, indicating the variable capacity of I-PfoP3I. I-PfoP3I cleaves 4 nt upstream of the intron insertion site on the coding strand of EXON 1 on both intron-minus Pf-WMP3 and Pf-WMP4 DNA polymerase genes. Using an in vitro cleavage assay and scanning deletion mutants of the intronless target site, the minimal recognition site was determined to be a 14 bp region downstream of the cut site. I-PfoP3I requires Mg2+, Ca2+ or Mn2+ for nicking activity. Phylogenetic analysis suggests that the intron and homing endonuclease gene elements might be inserted in Pf-WMP3 genome individually after differentiation from Pf-WMP4. To our knowledge, this is the first report of the presence of a group I self-splicing intron encoding a functional homing endonuclease in a protein-coding gene in a cyanophage genome.
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Casjens SR, Molineux IJ. Short noncontractile tail machines: adsorption and DNA delivery by podoviruses. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 726:143-79. [PMID: 22297513 DOI: 10.1007/978-1-4614-0980-9_7] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Tailed dsDNA bacteriophage virions bind to susceptible cells with the tips of their tails and then deliver their DNA through the tail into the cells to initiate infection. This chapter discusses what is known about this process in the short-tailed phages (Podoviridae). Their short tails require that many of these virions adsorb to the outer layers of the cell and work their way down to the outer membrane surface before releasing their DNA. Interestingly, the receptor-binding protein of many short-tailed phages (and some with long tails) has an enzymatic activity that cleaves their polysaccharide receptors. Reversible adsorption and irreversible adsorption to primary and secondary receptors are discussed, including how sequence divergence in tail fiber and tailspike proteins leads to different host specificities. Upon reaching the outer membrane of Gram-negative cells, some podoviral tail machines release virion proteins into the cell that help the DNA efficiently traverse the outer layers of the cell and/or prepare the cell cytoplasm for phage genome arrival. Podoviruses utilize several rather different variations on this theme. The virion DNA is then released into the cell; the energetics of this process is discussed. Phages like T7 and N4 deliver their DNA relatively slowly, using enzymes to pull the genome into the cell. At least in part this mechanism ensures that genes in late-entering DNA are not expressed at early times. On the other hand, phages like P22 probably deliver their DNA more rapidly so that it can be circularized before the cascade of gene expression begins.
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Affiliation(s)
- Sherwood R Casjens
- Pathology Department, University of Utah School of Medicine, Salt Lake City, UT 84112, USA.
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36
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Huang S, Wang K, Jiao N, Chen F. Genome sequences of siphoviruses infecting marine Synechococcus unveil a diverse cyanophage group and extensive phage-host genetic exchanges. Environ Microbiol 2011; 14:540-58. [DOI: 10.1111/j.1462-2920.2011.02667.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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37
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Intracellular assembly of cyanophage Syn5 proceeds through a scaffold-containing procapsid. J Virol 2010; 85:2406-15. [PMID: 21177804 DOI: 10.1128/jvi.01601-10] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Syn5 is a marine cyanophage that is propagated on the marine photosynthetic cyanobacterial strain Synechococcus sp. WH8109 under laboratory conditions. Cryoelectron images of this double-stranded DNA (dsDNA) phage reveal an icosahedral capsid with short tail appendages and a single novel hornlike structure at the vertex opposite the tail. Despite the major impact of cyanophages on life in the oceans, there is limited information on cyanophage intracellular assembly processes within their photosynthetic hosts. The one-step growth curve of Syn5 demonstrated a short cycle with an eclipse period of ∼45 min, a latent phase of ∼60 min, and a burst size of 20 to 30 particles per cell at 28°C. SDS-PAGE and Western blot analysis of cell lysates at different times after infection showed the synthesis of major virion proteins and their increase as the infection progressed. The scaffolding protein of Syn5, absent from virions, was identified in the lysates and expressed from the cloned gene. It migrated anomalously on SDS-PAGE, similar to the phage T7 scaffolding protein. Particles lacking DNA but containing the coat and scaffolding proteins were purified from Syn5-infected cells using CsCl centrifugation followed by sucrose gradient centrifugation. Electron microscopic images of the purified particles showed shells lacking condensed DNA but filled with protein density, presumably scaffolding protein. These findings suggest that the cyanophages form infectious virions through the initial assembly of scaffolding-containing procapsids, similar to the assembly pathways for the enteric dsDNA bacteriophages. Since cyanobacteria predate the enteric bacteria, this procapsid-mediated assembly pathway may have originated with the cyanophages.
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Abstract
Pseudomonas species and their bacteriophages have been studied intensely since the beginning of the 20th century, due to their ubiquitous nature, and medical and ecological importance. Here, we summarize recent molecular research performed on Pseudomonas phages by reviewing findings on individual phage genera. While large phage collections are stored and characterized worldwide, the limits of their genomic diversity are becoming more and more apparent. Although this article emphasizes the biological background and molecular characteristics of these phages, special attention is given to emerging studies in coevolutionary and in therapeutic settings.
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Affiliation(s)
- Pieter-Jan Ceyssens
- Department of Biosystems, Katholieke Universiteit Leuven, Kasteelpark Arenberg 21, bus 2462, B-3001 Leuven, Belgium
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39
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Wang S, Qiao X, Liu X, Zhang X, Wang C, Zhao X, Chen Z, Wen Y, Song Y. Complete genomic sequence analysis of the temperate bacteriophage phiSASD1 of Streptomyces avermitilis. Virology 2010; 403:78-84. [PMID: 20447671 DOI: 10.1016/j.virol.2010.03.044] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2009] [Revised: 03/23/2010] [Accepted: 03/29/2010] [Indexed: 10/19/2022]
Abstract
The bacteriophage phiSASD1, isolated from a failed industrial avermectin fermentation, belongs to the Siphoviridae family. Its four predominant structural proteins, which include the major capsid, portal and two tail-related proteins, were separated and identified by SDS-PAGE and N-terminal sequence analysis. The entire double-stranded DNA genome of phiSASD1 consists of 37,068 bp, with 3'-protruding cohesive ends of nine nucleotides. Putative biological functions have been assigned to 24 of the 43 potential open reading frames. Comparative analysis shows perfect assembly of three "core" gene modules: the morphogenesis and head module, the tail module and the right arm gene module, which displays obvious similarity to the right arm genes of Streptomyces phage phiC31 in function and arrangement. Meanwhile, structural module flexibility within phiSASD1 suggests that assignment of phage taxonomy based on comparative genomics of structural genes will be more complex than expected due to the exchangeability of functional genetic elements.
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Affiliation(s)
- Shiwei Wang
- Department of Microbiology, College of Biological Sciences, China Agricultural University, Beijing, PR China.
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40
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Abstract
We designed and constructed a controllable inducing lysis system in Synechocystis sp. PCC 6803 to facilitate extracting lipids for biofuel production. Several bacteriophage-derived lysis genes were integrated into the genome and placed downstream of a nickel-inducible signal transduction system. We applied 3 strategies: (i) directly using the phage lysis cassette, (ii) constitutively expressing endolysin genes while restricting holin genes, and (iii) combining lysis genes from different phages. Significant autolysis was induced in the Synechocystis sp. PCC 6803 cells with this system by the addition of NiSO(4). Our inducible cyanobacterial lysing system eliminates the need for mechanical or chemical cell breakage and could facilitate recovery of biofuel from cyanobacteria.
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41
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Liu X, Kong S, Shi M, Fu L, Gao Y, An C. Genomic analysis of freshwater cyanophage Pf-WMP3 Infecting cyanobacterium Phormidium foveolarum: the conserved elements for a phage. MICROBIAL ECOLOGY 2008; 56:671-80. [PMID: 18443848 DOI: 10.1007/s00248-008-9386-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2007] [Revised: 02/17/2008] [Accepted: 02/20/2008] [Indexed: 05/14/2023]
Abstract
Cyanophages are ecologically abundant, genetically diverse in aquatic environments, and affect the population and evolutionary trajectories of their hosts. After reporting the cyanophage Pf-WMP4 genome (Liu et al. in Virology 366:28-39, 2007), we hereby present a related cyanophage, Pf-WMP3, which also infects the freshwater cyanobacterium Phormidium foveolarum. The Pf-WMP3 genome contains 43,249 bp with 234 bp direct terminal repeats. The overall genome organization and core genes of the two phages are comparable to those of the T7 supergroup phages. Compared with Pf-WMP4, cyanophage Pf-WMP3 has diverged extensively at the DNA level; however, they are closely related at the protein level and genome architecture. The left arm genes for the two phages, which mainly encode the DNA replication machinery, are not conserved in the gene order. Whereas the right arm genes of the two phages coding for structural proteins show high similarity in amino acid sequences and modular architecture, indicating that they have retained similar development strategies. The differences in similarity levels between the left and right arm genes suggest that the structural genes are the most conserved elements for a phage.
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Affiliation(s)
- Xinyao Liu
- National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing 100871, People's Republic of China.
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The intron-containing genome of the lytic Pseudomonas phage LUZ24 resembles the temperate phage PaP3. Virology 2008; 377:233-8. [PMID: 18519145 DOI: 10.1016/j.virol.2008.04.038] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2008] [Revised: 04/16/2008] [Accepted: 04/28/2008] [Indexed: 11/22/2022]
Abstract
The virulent Pseudomonas aeruginosa bacteriophage LUZ24 (45,625 bp) was isolated from hospital sewage. It belongs to the family of the Podoviridae, and carries a bidirectionally transcribed dsDNA genome delineated by two direct terminal repeats of 184 bp. In vitro transcriptional analysis identified seven sigma(70) promoters, revealing a bias towards stronger promoter strength in the late genomic region. Reverse transcription demonstrated in vivo splicing of a 668 bp Group I intron embedded inside the DNA polymerase gene. Using mass spectrometry, nine structural proteins were identified as part of the phage particle. The lytic characteristics of LUZ24 are evaluated against its genomic content, which displays an overall 71% sequence similarity to the temperate phage PaP3.
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Abstract
Cyanophages that infect coastal and oceanic Synechococcus have been studied extensively. However, no cyanophages infecting estuarine Synechococcus have been reported. In this study, seven cyanophages (three podoviruses, three siphoviruses and one myovirus) isolated from four estuarine Synechococcus strains were characterized in terms of their morphology, host range, growth and genetic features. All the podoviruses and siphoviruses were highly host specific. For the first time, the photosynthesis gene (psbA) was found in two podoviruses infecting estuarine Synechococcus. However, the psbA gene was not detected in the three siphoviruses. The psbA sequences from the two Synechococcus podoviruses clustered with some environmental psbA sequences, forming a unique cluster distantly related to previous known psbA clusters. Our results suggest that the psbA among Synechococcus podoviruses may evolve independently from the psbA of Synechococcus myoviruses. All three estuarine Synechococcus podoviruses contained the DNA polymerase (pol) gene, and clustered with other podoviruses that infect oceanic Synechococcus and Prochlorococcus, suggesting that the DNA pol is conserved among marine picocyanobacterial podoviruses. Prevalence of host-specific cyanophages in the estuary suggests that Synechococcus and their phages in the estuarine ecosystem may develop a host-phage relationship different from what have been found in the open ocean.
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Affiliation(s)
- Kui Wang
- Center of Marine Biotechnology, University of Maryland Biotechnology Institute, 701 E Pratt Street, Baltimore, MD 21202, USA
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