101
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Šulčius S, Mazur-Marzec H, Vitonytė I, Kvederavičiūtė K, Kuznecova J, Šimoliūnas E, Holmfeldt K. Insights into cyanophage-mediated dynamics of nodularin and other non-ribosomal peptides in Nodularia spumigena. HARMFUL ALGAE 2018; 78:69-74. [PMID: 30196926 DOI: 10.1016/j.hal.2018.07.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 07/09/2018] [Accepted: 07/10/2018] [Indexed: 06/08/2023]
Abstract
The effect of cyanophage infection and lysis on the dynamics of the hepatotoxin nodularin (NOD) and other non-ribosomal peptides (NRPs) produced by cyanobacteria is poorly understood. In this study, changes in concentration of NOD and other NRPs during cyanophage infection of the filamentous cyanobacteria Nodularia spumigena were assessed using incubation experiments. Viral infection and lysis were associated with a significant reduction (93% at the 96 h post infection) of N. spumigena cell density. While no correlation between N. spumigena abundance and total concentration of NOD (ng mL-1) within the infected cells was observed, cellular NOD quota (ng cell-1) gradually increased in the remaining cyanophage resistant N. spumigena subpopulation. Lysis of N. spumigena cells resulted in a substantial increase (>57 times) of dissolved NOD concentration in the culture medium. The relative concentration of other cyclic (anabaenopeptins) and linear (aeruginosins, spumigins) NRPs produced by N. spumigena also increased in response to cyanophage addition. This study highlights the importance of cyanophage infection on the population toxicity of filamentous cyanobacteria and demonstrates a significant contribution of virus-mediated cell lysis on the conversion of NOD from the particulate to dissolved phase.
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Affiliation(s)
- Sigitas Šulčius
- Laboratory of Algology and Microbial Ecology, Nature Research Centre, Akademijos str. 2, LT-08412, Vilnius, Lithuania; Center for Ecology and Evolution in Microbial Model Systems, Department of Biology and Environmental Science, Linnaeus University, Barlastgatan 11, SE-39231, Kalmar, Sweden.
| | - Hanna Mazur-Marzec
- Department of Marine Biotechnology, Institute of Oceanography, University of Gdańsk, Marszałka Józefa Piłsudskiego 46, PL-81378, Gdynia, Poland; Institute of Oceanology, Polish Academy of Sciences, Powstańców Warszawy 55, PL-81712 Sopot, Poland
| | - Irma Vitonytė
- Laboratory of Algology and Microbial Ecology, Nature Research Centre, Akademijos str. 2, LT-08412, Vilnius, Lithuania
| | - Kotryna Kvederavičiūtė
- MAP Kinase Resource, Melchiorstrasse 9, CH-3027, Bern, Switzerland; Institute of Biotechnology, Vilnius University, Saulėtekio av. 7, LT-10257, Vilnius, Lithuania
| | - Jolita Kuznecova
- Laboratory of Algology and Microbial Ecology, Nature Research Centre, Akademijos str. 2, LT-08412, Vilnius, Lithuania
| | - Eugenijus Šimoliūnas
- Institute of Biochemistry, Vilnius University, Saulėtekio av. 7, LT-10257, Vilnius, Lithuania
| | - Karin Holmfeldt
- Center for Ecology and Evolution in Microbial Model Systems, Department of Biology and Environmental Science, Linnaeus University, Barlastgatan 11, SE-39231, Kalmar, Sweden
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102
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Coutinho FH, Gregoracci GB, Walter JM, Thompson CC, Thompson FL. Metagenomics Sheds Light on the Ecology of Marine Microbes and Their Viruses. Trends Microbiol 2018; 26:955-965. [PMID: 29937307 DOI: 10.1016/j.tim.2018.05.015] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Revised: 05/18/2018] [Accepted: 05/29/2018] [Indexed: 01/31/2023]
Abstract
Advances brought about by omics-based approaches have revolutionized our understanding of the diversity and ecological processes involving marine archaea, bacteria, and their viruses. This broad review discusses recent examples of how genomics, metagenomics, and ecogenomics have been applied to reveal the ecology of these biological entities. Three major topics are covered in this revision: (i) the novel roles of microorganisms in ecosystem processes; (ii) virus-host associations; and (iii) ecological associations of microeukaryotes and other microbes. We also briefly comment on the discovery of novel taxa from marine ecosystems; development of a robust taxonomic framework for prokaryotes; breakthroughs on the diversity and ecology of cyanobacteria; and advances on ecological modelling. We conclude by discussing limitations of the field and suggesting directions for future research.
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Affiliation(s)
- Felipe Hernandes Coutinho
- Laboratory of Microbiology, Instituto de Biologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil; Evolutionary Genomics Group, Departamento de Produccíon Vegetal y Microbiología, Universidad Miguel Hernández (UMH), Alicante, Spain
| | | | - Juline Marta Walter
- Laboratory of Microbiology, Instituto de Biologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Cristiane Carneiro Thompson
- Laboratory of Microbiology, Instituto de Biologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Fabiano L Thompson
- Laboratory of Microbiology, Instituto de Biologia, Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil; Center of Technology - CT2, SAGE-COPPE, Federal Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil.
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103
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Breitbart M, Bonnain C, Malki K, Sawaya NA. Phage puppet masters of the marine microbial realm. Nat Microbiol 2018; 3:754-766. [PMID: 29867096 DOI: 10.1038/s41564-018-0166-y] [Citation(s) in RCA: 322] [Impact Index Per Article: 53.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 04/20/2018] [Indexed: 11/09/2022]
Abstract
Viruses numerically dominate our oceans; however, we have only just begun to document the diversity, host range and infection dynamics of marine viruses, as well as the subsequent effects of infection on both host cell metabolism and oceanic biogeochemistry. Bacteriophages (that is, phages: viruses that infect bacteria) are highly abundant and are known to play critical roles in bacterial mortality, biogeochemical cycling and horizontal gene transfer. This Review Article summarizes current knowledge of marine viral ecology and highlights the importance of phage particles to the dissolved organic matter pool, as well as the complex interactions between phages and their bacterial hosts. We emphasize the newly recognized roles of phages as puppet masters of their bacterial hosts, where phages are capable of altering the metabolism of infected bacteria through the expression of auxiliary metabolic genes and the redirection of host gene expression patterns. Finally, we propose the 'royal family model' as a hypothesis to describe successional patterns of bacteria and phages over time in marine systems, where despite high richness and significant seasonal differences, only a small number of phages appear to continually dominate a given marine ecosystem. Although further testing is required, this model provides a framework for assessing the specificity and ecological consequences of phage-host dynamics.
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Affiliation(s)
- Mya Breitbart
- College of Marine Science, University of South Florida, Saint Petersburg, FL, USA.
| | - Chelsea Bonnain
- College of Marine Science, University of South Florida, Saint Petersburg, FL, USA
| | - Kema Malki
- College of Marine Science, University of South Florida, Saint Petersburg, FL, USA
| | - Natalie A Sawaya
- College of Marine Science, University of South Florida, Saint Petersburg, FL, USA
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104
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Forterre P. Viruses in the 21st Century: From the Curiosity-Driven Discovery of Giant Viruses to New Concepts and Definition of Life. Clin Infect Dis 2018; 65:S74-S79. [PMID: 28859344 DOI: 10.1093/cid/cix349] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The curiosity-driven discovery of giant DNA viruses infecting amoebas has triggered an intense debate about the origin, nature, and definition of viruses. This discovery was delayed by the current paradigm confusing viruses with small virions. Several new definitions and concepts have been proposed either to reconcile the unique features of giant viruses with previous paradigms or to propose a completely new vision of the living world. I briefly review here how several other lines of research in virology converged during the last 2 decades with the discovery of giant viruses to change our traditional perception of the viral world. This story emphasizes the power of multidisciplinary curiosity-driven research, from the hospital to the field and the laboratory. Notably, some philosophers have now also joined biologists in their quest to make sense of the abundance and diversity of viruses and related capsidless mobile elements in the biosphere.
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Affiliation(s)
- Patrick Forterre
- Institut Pasteur, Département de Microbiologie, Paris; and Institut Intégré de Biologie Cellulaire, Département de Microbiologie, Centre National de la Recherche Scientifique, Université Paris-Saclay, France
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105
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Moniruzzaman M, Gann ER, Wilhelm SW. Infection by a Giant Virus (AaV) Induces Widespread Physiological Reprogramming in Aureococcus anophagefferens CCMP1984 - A Harmful Bloom Algae. Front Microbiol 2018; 9:752. [PMID: 29725322 PMCID: PMC5917014 DOI: 10.3389/fmicb.2018.00752] [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: 01/29/2018] [Accepted: 04/03/2018] [Indexed: 01/05/2023] Open
Abstract
While viruses with distinct phylogenetic origins and different nucleic acid types can infect and lyse eukaryotic phytoplankton, “giant” dsDNA viruses have been found to be associated with important ecological processes, including the collapse of algal blooms. However, the molecular aspects of giant virus–host interactions remain largely unknown. Aureococcus anophagefferens virus (AaV), a giant virus in the Mimiviridae clade, is known to play a critical role in regulating the fate of brown tide blooms caused by the pelagophyte Aureococcus anophagefferens. To understand the physiological response of A. anophagefferens CCMP1984 upon AaV infection, we studied the transcriptomic landscape of this host–virus pair over an entire infection cycle using a RNA-sequencing approach. A massive transcriptional response of the host was evident as early as 5 min post-infection, with modulation of specific processes likely related to both host defense mechanism(s) and viral takeover of the cell. Infected Aureococcus showed a relative suppression of host-cell transcripts associated with photosynthesis, cytoskeleton formation, fatty acid, and carbohydrate biosynthesis. In contrast, host cell processes related to protein synthesis, polyamine biosynthesis, cellular respiration, transcription, and RNA processing were overrepresented compared to the healthy cultures at different stages of the infection cycle. A large number of redox active host-selenoproteins were overexpressed, which suggested that viral replication and assembly progresses in a highly oxidative environment. The majority (99.2%) of annotated AaV genes were expressed at some point during the infection cycle and demonstrated a clear temporal–expression pattern and an increasing relative expression for the majority of the genes through the time course. We detected a putative early promoter motif for AaV, which was highly similar to the early promoter elements of two other Mimiviridae members, indicating some degree of evolutionary conservation of gene regulation within this clade. This large-scale transcriptome study provides insights into the Aureococcus cells infected by a giant virus and establishes a foundation to test hypotheses regarding metabolic and regulatory processes critical for AaV and other Mimiviridae members.
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Affiliation(s)
- Mohammad Moniruzzaman
- Department of Microbiology, The University of Tennessee, Knoxville, Knoxville, TN, United States.,Monterey Bay Aquarium Research Institute (MBARI), Moss Landing, CA, United States
| | - Eric R Gann
- Department of Microbiology, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Steven W Wilhelm
- Department of Microbiology, The University of Tennessee, Knoxville, Knoxville, TN, United States
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106
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Schvarcz CR, Steward GF. A giant virus infecting green algae encodes key fermentation genes. Virology 2018; 518:423-433. [PMID: 29649682 DOI: 10.1016/j.virol.2018.03.010] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 03/08/2018] [Accepted: 03/11/2018] [Indexed: 11/29/2022]
Abstract
The family Mimiviridae contains uncommonly large viruses, many of which were isolated using a free-living amoeba as a host. Although the genomes of these and other mimivirids that infect marine heterokont and haptophyte protists have now been sequenced, there has yet to be a genomic investigation of a mimivirid that infects a member of the Viridiplantae lineage (green algae and land plants). Here we characterize the 668-kilobase complete genome of TetV-1, a mimivirid that infects the cosmopolitan green alga Tetraselmis (Chlorodendrophyceae). The analysis revealed genes not previously seen in viruses, such as the mannitol metabolism enzyme mannitol 1-phosphate dehydrogenase, the saccharide degradation enzyme alpha-galactosidase, and the key fermentation genes pyruvate formate-lyase and pyruvate formate-lyase activating enzyme. The TetV genome is the largest sequenced to date for a virus that infects a photosynthetic organism, and its genes reveal unprecedented mechanisms by which viruses manipulate their host's metabolism.
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Affiliation(s)
- Christopher R Schvarcz
- Department of Oceanography, Daniel K. Inouye Center for Microbial Oceanography: Research and Education, University of Hawai'i at Mānoa, 1950 East-West Road, Honolulu, HI 96822, United States
| | - Grieg F Steward
- Department of Oceanography, Daniel K. Inouye Center for Microbial Oceanography: Research and Education, University of Hawai'i at Mānoa, 1950 East-West Road, Honolulu, HI 96822, United States.
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107
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Danovaro R, Corinaldesi C, Dell'Anno A, Rastelli E. Potential impact of global climate change on benthic deep-sea microbes. FEMS Microbiol Lett 2018; 364:4553516. [PMID: 29045616 DOI: 10.1093/femsle/fnx214] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Accepted: 10/12/2017] [Indexed: 11/12/2022] Open
Abstract
Benthic deep-sea environments are the largest ecosystem on Earth, covering ∼65% of the Earth surface. Microbes inhabiting this huge biome at all water depths represent the most abundant biological components and a relevant portion of the biomass of the biosphere, and play a crucial role in global biogeochemical cycles. Increasing evidence suggests that global climate changes are affecting also deep-sea ecosystems, both directly (causing shifts in bottom-water temperature, oxygen concentration and pH) and indirectly (through changes in surface oceans' productivity and in the consequent export of organic matter to the seafloor). However, the responses of the benthic deep-sea biota to such shifts remain largely unknown. This applies particularly to deep-sea microbes, which include bacteria, archaea, microeukaryotes and their viruses. Understanding the potential impacts of global change on the benthic deep-sea microbial assemblages and the consequences on the functioning of the ocean interior is a priority to better forecast the potential consequences at global scale. Here we explore the potential changes in the benthic deep-sea microbiology expected in the coming decades using case studies on specific systems used as test models.
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Affiliation(s)
- Roberto Danovaro
- Department of Life and Environmental Sciences, Polytechnic University of Marche, 60131 Ancona, Italy.,Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy
| | - Cinzia Corinaldesi
- Department of Sciences and Engineering of Materials, Environment and Urbanistics, Polytechnic University of Marche, 60131 Ancona, Italy
| | - Antonio Dell'Anno
- Department of Life and Environmental Sciences, Polytechnic University of Marche, 60131 Ancona, Italy
| | - Eugenio Rastelli
- Department of Life and Environmental Sciences, Polytechnic University of Marche, 60131 Ancona, Italy.,Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy
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108
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Sheyn U, Rosenwasser S, Lehahn Y, Barak-Gavish N, Rotkopf R, Bidle KD, Koren I, Schatz D, Vardi A. Expression profiling of host and virus during a coccolithophore bloom provides insights into the role of viral infection in promoting carbon export. ISME JOURNAL 2018; 12:704-713. [PMID: 29335637 DOI: 10.1038/s41396-017-0004-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 09/19/2017] [Accepted: 10/08/2017] [Indexed: 11/09/2022]
Abstract
The cosmopolitan coccolithophore Emiliania huxleyi is a unicellular eukaryotic alga that forms vast blooms in the oceans impacting large biogeochemical cycles. These blooms are often terminated due to infection by the large dsDNA virus, E. huxleyi virus (EhV). It was recently established that EhV-induced modulation of E. huxleyi metabolism is a key factor for optimal viral infection cycle. Despite the huge ecological importance of this host-virus interaction, the ability to assess its spatial and temporal dynamics and its possible impact on nutrient fluxes is limited by current approaches that focus on quantification of viral abundance and biodiversity. Here, we applied a host and virus gene expression analysis as a sensitive tool to quantify the dynamics of this interaction during a natural E. huxleyi bloom in the North Atlantic. We used viral gene expression profiling as an index for the level of active infection and showed that the latter correlated with water column depth. Intriguingly, this suggests a possible sinking mechanism for removing infected cells as aggregates from the E. huxleyi population in the surface layer into deeper waters. Viral infection was also highly correlated with induction of host metabolic genes involved in host life cycle, sphingolipid, and antioxidant metabolism, providing evidence for modulation of host metabolism under natural conditions. The ability to track and quantify defined phases of infection by monitoring co-expression of viral and host genes, coupled with advance omics approaches, will enable a deeper understanding of the impact that viruses have on the environment.
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Affiliation(s)
- Uri Sheyn
- Departments of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Shilo Rosenwasser
- Departments of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, 7610001, Israel.,The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University, Rehovot, 7610001, Israel
| | - Yoav Lehahn
- Departments of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Noa Barak-Gavish
- Departments of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Ron Rotkopf
- Department of Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Kay D Bidle
- Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, NJ, 08901, USA
| | - Ilan Koren
- Departments of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Daniella Schatz
- Departments of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Assaf Vardi
- Departments of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, 7610001, Israel.
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109
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Tennant P, Fermin G. Beneficial Interactions with Viruses. Viruses 2018. [DOI: 10.1016/b978-0-12-811257-1.00011-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
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110
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Frada MJ, Rosenwasser S, Ben-Dor S, Shemi A, Sabanay H, Vardi A. Morphological switch to a resistant subpopulation in response to viral infection in the bloom-forming coccolithophore Emiliania huxleyi. PLoS Pathog 2017; 13:e1006775. [PMID: 29244854 PMCID: PMC5756048 DOI: 10.1371/journal.ppat.1006775] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 01/05/2018] [Accepted: 11/27/2017] [Indexed: 11/18/2022] Open
Abstract
Recognizing the life cycle of an organism is key to understanding its biology and ecological impact. Emiliania huxleyi is a cosmopolitan marine microalga, which displays a poorly understood biphasic sexual life cycle comprised of a calcified diploid phase and a morphologically distinct biflagellate haploid phase. Diploid cells (2N) form large-scale blooms in the oceans, which are routinely terminated by specific lytic viruses (EhV). In contrast, haploid cells (1N) are resistant to EhV. Further evidence indicates that 1N cells may be produced during viral infection. A shift in morphology, driven by meiosis, could therefore constitute a mechanism for E. huxleyi cells to escape from EhV during blooms. This process has been metaphorically coined the 'Cheshire Cat' (CC) strategy. We tested this model in two E. huxleyi strains using a detailed assessment of morphological and ploidy-level variations as well as expression of gene markers for meiosis and the flagellate phenotype. We showed that following the CC model, production of resistant cells was triggered during infection. This led to the rise of a new subpopulation of cells in the two strains that morphologically resembled haploid cells and were resistant to EhV. However, ploidy-level analyses indicated that the new resistant cells were diploid or aneuploid. Thus, the CC strategy in E. huxleyi appears to be a life-phase switch mechanism involving morphological remodeling that is decoupled from meiosis. Our results highlight the adaptive significance of morphological plasticity mediating complex host-virus interactions in marine phytoplankton.
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Affiliation(s)
- Miguel José Frada
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Shilo Rosenwasser
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Shifra Ben-Dor
- Bioinformatics and Biological Computing Unit–Department of Biological Services, Weizmann Institute of Science, Rehovot, Israel
| | - Adva Shemi
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Helena Sabanay
- Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, Israel
| | - Assaf Vardi
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
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111
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Anderson CL, Sullivan MB, Fernando SC. Dietary energy drives the dynamic response of bovine rumen viral communities. MICROBIOME 2017; 5:155. [PMID: 29179741 PMCID: PMC5704599 DOI: 10.1186/s40168-017-0374-3] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 11/14/2017] [Indexed: 05/05/2023]
Abstract
BACKGROUND Rumen microbes play a greater role in host energy acquisition than that of gut-associated microbes in monogastric animals. Although genome-enabled advancements are providing access to the vast diversity of uncultivated microbes, our understanding of variables shaping rumen microbial communities is in its infancy. Viruses have been shown to impact microbial populations through a myriad of processes, including cell lysis and reprogramming of host metabolism. However, little is known about the processes shaping the distribution of rumen viruses or how viruses may modulate microbial-driven processes in the rumen. To this end, we investigated how rumen bacterial and viral community structure and function responded in five steers fed four randomized dietary treatments in a crossover design. RESULTS Total digestible nutrients (TDN), a measure of dietary energy, best explained the variation in bacterial and viral communities. Additional ecological drivers of viral communities included dietary zinc content and microbial functional diversity. Using partial least squares regression, we demonstrate significant associations between the abundances of 267 viral populations and variables driving the variation in rumen viral communities. While rumen viruses were dynamic, 14 near ubiquitous viral populations were identified, suggesting the presence of a core rumen virome largely comprised of novel viruses. Moreover, analysis of virally encoded auxiliary metabolic genes (AMGs) indicates rumen viruses have glycosidic hydrolases to potentially augment the breakdown of complex carbohydrates to increase energy production. Other AMGs identified have a role in redirecting carbon to the pentose phosphate pathway and one carbon pools by folate to boost viral replication. CONCLUSIONS We demonstrate that rumen bacteria and viruses have differing responses and ecological drivers to dietary perturbation. Our results show that rumen viruses have implications for understanding the structuring of the previously identified core rumen microbiota and impacting microbial metabolism through a vast array of AMGs. AMGs in the rumen appear to have consequences for microbial metabolism that are largely in congruence with the current paradigm established in marine systems. This study provides a foundation for future hypotheses regarding the dynamics of viral-mediated processes in the rumen.
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Affiliation(s)
- Christopher L. Anderson
- School of Biological Sciences, University of Nebraska, Lincoln, NE 68588 USA
- Department of Animal Science, University of Nebraska-Lincoln, C220K Animal Science Complex, Lincoln, NE 68583-0908 USA
| | - Matthew B. Sullivan
- Departments of Microbiology, and Civil, Environmental and Geodetic Engineering, The Ohio State University, Riffe Building 266, 496 W 12th Ave, Columbus, OH 43210 USA
| | - Samodha C. Fernando
- Department of Animal Science, University of Nebraska-Lincoln, C220K Animal Science Complex, Lincoln, NE 68583-0908 USA
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112
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Brodie J, Ball SG, Bouget FY, Chan CX, De Clerck O, Cock JM, Gachon C, Grossman AR, Mock T, Raven JA, Saha M, Smith AG, Vardi A, Yoon HS, Bhattacharya D. Biotic interactions as drivers of algal origin and evolution. THE NEW PHYTOLOGIST 2017; 216:670-681. [PMID: 28857164 DOI: 10.1111/nph.14760] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 07/10/2017] [Indexed: 05/07/2023]
Abstract
Contents 670 I. 671 II. 671 III. 676 IV. 678 678 References 678 SUMMARY: Biotic interactions underlie life's diversity and are the lynchpin to understanding its complexity and resilience within an ecological niche. Algal biologists have embraced this paradigm, and studies building on the explosive growth in omics and cell biology methods have facilitated the in-depth analysis of nonmodel organisms and communities from a variety of ecosystems. In turn, these advances have enabled a major revision of our understanding of the origin and evolution of photosynthesis in eukaryotes, bacterial-algal interactions, control of massive algal blooms in the ocean, and the maintenance and degradation of coral reefs. Here, we review some of the most exciting developments in the field of algal biotic interactions and identify challenges for scientists in the coming years. We foresee the development of an algal knowledgebase that integrates ecosystem-wide omics data and the development of molecular tools/resources to perform functional analyses of individuals in isolation and in populations. These assets will allow us to move beyond mechanistic studies of a single species towards understanding the interactions amongst algae and other organisms in both the laboratory and the field.
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Affiliation(s)
- Juliet Brodie
- Department of Life Sciences, Natural History Museum, London, SW7 5BD, UK
| | - Steven G Ball
- UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, Université de Lille CNRS, F 59000, Lille, France
| | - François-Yves Bouget
- Laboratoire d'Océanographie Microbienne, Observatoire Océanologique, University Pierre et Marie Curie, University of Paris VI, CNRS, F-66650, Banyuls-sur-Mer, France
| | - Cheong Xin Chan
- Institute for Molecular Bioscience and School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, Qld, 4072, Australia
| | - Olivier De Clerck
- Phycology Research Group, Ghent University, Krijgslaan 281, S8, 9000, Gent, Belgium
| | - J Mark Cock
- CNRS, Sorbonne Université, UPMC University Paris 06, Algal Genetics Group, UMR 8227, Integrative Biology of Marine Models, Station Biologique de Roscoff, CS 90074, Roscoff, F-29688, France
| | | | - Arthur R Grossman
- Department of Plant Biology, The Carnegie Institution for Science, Stanford, CA, 94305, USA
| | - Thomas Mock
- School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, UK
| | - John A Raven
- Division of Plant Sciences, University of Dundee at the James Hutton Institute, Dundee, DD2 5DA, UK
| | - Mahasweta Saha
- Helmholtz Center for Ocean Research, Kiel, 24105, Germany
| | - Alison G Smith
- Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, UK
| | - Assaf Vardi
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Hwan Su Yoon
- Department of Biological Sciences, Sungkyunkwan University, Suwon, 440-746, South Korea
| | - Debashish Bhattacharya
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ, 08901, USA
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113
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Williamson KE, Fuhrmann JJ, Wommack KE, Radosevich M. Viruses in Soil Ecosystems: An Unknown Quantity Within an Unexplored Territory. Annu Rev Virol 2017; 4:201-219. [PMID: 28961409 DOI: 10.1146/annurev-virology-101416-041639] [Citation(s) in RCA: 158] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Viral abundance in soils can range from below detection limits in hot deserts to over 1 billion per gram in wetlands. Abundance appears to be strongly influenced by water availability and temperature, but a lack of informational standards creates difficulties for cross-study analysis. Soil viral diversity is severely underestimated and undersampled, although current measures of viral richness are higher for soils than for aquatic ecosystems. Both morphometric and metagenomic analyses have raised questions about the prevalence of nontailed, ssDNA viruses in soils. Soil is complex and critically important to terrestrial biodiversity and human civilization, but impacts of viral activities on soil ecosystem services are poorly understood. While information from aquatic systems and medical microbiology suggests the potential for viral influences on nutrient cycles, food web interactions, gene transfer, and other key processes in soils, very few empirical data are available. To understand the soil virome, much work remains.
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Affiliation(s)
- Kurt E Williamson
- Biology Department, College of William and Mary, Williamsburg, Virginia 23185;
| | - Jeffry J Fuhrmann
- Department of Plant and Soil Sciences, University of Delaware, Newark, Delaware 19716
| | - K Eric Wommack
- Department of Plant and Soil Sciences, University of Delaware, Newark, Delaware 19716.,Department Biological Sciences, University of Delaware, Newark, Delaware 19716.,College of Earth, Ocean, and Environment, University of Delaware, Newark, Delaware 19716
| | - Mark Radosevich
- Biosystems Engineering and Soil Science Department, University of Tennessee, Knoxville, Tennessee 37996
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114
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Rastelli E, Corinaldesi C, Dell'Anno A, Tangherlini M, Martorelli E, Ingrassia M, Chiocci FL, Lo Martire M, Danovaro R. High potential for temperate viruses to drive carbon cycling in chemoautotrophy-dominated shallow-water hydrothermal vents. Environ Microbiol 2017; 19:4432-4446. [DOI: 10.1111/1462-2920.13890] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 07/06/2017] [Accepted: 08/08/2017] [Indexed: 11/29/2022]
Affiliation(s)
- Eugenio Rastelli
- Department of Life and Environmental Sciences; Polytechnic University of Marche; Ancona 60131 Italy
- Stazione Zoologica Anton Dohrn; Villa Comunale; Naples 80121 Italy
| | - Cinzia Corinaldesi
- Department of Life and Environmental Sciences; Polytechnic University of Marche; Ancona 60131 Italy
| | - Antonio Dell'Anno
- Department of Life and Environmental Sciences; Polytechnic University of Marche; Ancona 60131 Italy
| | - Michael Tangherlini
- Department of Life and Environmental Sciences; Polytechnic University of Marche; Ancona 60131 Italy
| | - Eleonora Martorelli
- Institute of Environmental Geology and Geoengineering; Italian National Research Council; Rome Italy
| | - Michela Ingrassia
- Institute of Environmental Geology and Geoengineering; Italian National Research Council; Rome Italy
- Department of Earth Science; University of Rome Sapienza; Rome Italy
| | - Francesco L. Chiocci
- Institute of Environmental Geology and Geoengineering; Italian National Research Council; Rome Italy
- Department of Earth Science; University of Rome Sapienza; Rome Italy
| | - Marco Lo Martire
- Department of Life and Environmental Sciences; Polytechnic University of Marche; Ancona 60131 Italy
| | - Roberto Danovaro
- Department of Life and Environmental Sciences; Polytechnic University of Marche; Ancona 60131 Italy
- Stazione Zoologica Anton Dohrn; Villa Comunale; Naples 80121 Italy
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115
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Young T, Kesarcodi-Watson A, Alfaro AC, Merien F, Nguyen TV, Mae H, Le DV, Villas-Bôas S. Differential expression of novel metabolic and immunological biomarkers in oysters challenged with a virulent strain of OsHV-1. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2017; 73:229-245. [PMID: 28373065 DOI: 10.1016/j.dci.2017.03.025] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Revised: 03/30/2017] [Accepted: 03/30/2017] [Indexed: 06/07/2023]
Abstract
Early lifestages of the Pacific oyster (Crassostrea gigas) are highly susceptible to infection by OsHV-1 μVar, but little information exists regarding metabolic or pathophysiological responses of larval hosts. Using a metabolomics approach, we identified a range of metabolic and immunological responses in oyster larvae exposed to OsHV-1 μVar; some of which have not previously been reported in molluscs. Multivariate analyses of entire metabolite profiles were able to separate infected from non-infected larvae. Correlation analysis revealed the presence of major perturbations in the underlying biochemical networks and secondary pathway analysis of functionally-related metabolites identified a number of prospective pathways differentially regulated in virus-exposed larvae. These results provide new insights into the pathogenic mechanisms of OsHV-1 infection in oyster larvae, which may be applied to develop disease mitigation strategies and/or as new phenotypic information for selective breeding programmes aiming to enhance viral resistance.
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Affiliation(s)
- Tim Young
- Institute for Applied Ecology New Zealand, School of Science, Faculty of Health and Environmental Sciences, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand; Metabolomics Laboratory, School of Biological Sciences, The University of Auckland, Private Bag 92019, Auckland Mail Centre, Auckland 1142, New Zealand
| | | | - Andrea C Alfaro
- Institute for Applied Ecology New Zealand, School of Science, Faculty of Health and Environmental Sciences, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand.
| | - Fabrice Merien
- AUT-Roche Diagnostics Laboratory, School of Science, Faculty of Health and Environmental Sciences, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand
| | - Thao V Nguyen
- Institute for Applied Ecology New Zealand, School of Science, Faculty of Health and Environmental Sciences, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand
| | - Hannah Mae
- Cawthron Institute, 98 Halifax Street East, Private Bag 2, Nelson 7042, New Zealand
| | - Dung V Le
- Institute for Applied Ecology New Zealand, School of Science, Faculty of Health and Environmental Sciences, Auckland University of Technology, Private Bag 92006, Auckland 1142, New Zealand
| | - Silas Villas-Bôas
- Metabolomics Laboratory, School of Biological Sciences, The University of Auckland, Private Bag 92019, Auckland Mail Centre, Auckland 1142, New Zealand
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116
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Danovaro R, Rastelli E, Corinaldesi C, Tangherlini M, Dell'Anno A. Marine archaea and archaeal viruses under global change. F1000Res 2017; 6:1241. [PMID: 29034077 PMCID: PMC5532796 DOI: 10.12688/f1000research.11404.1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/26/2017] [Indexed: 01/08/2023] Open
Abstract
Global change is altering oceanic temperature, salinity, pH, and oxygen concentration, directly and indirectly influencing marine microbial food web structure and function. As microbes represent >90% of the ocean’s biomass and are major drivers of biogeochemical cycles, understanding their responses to such changes is fundamental for predicting the consequences of global change on ecosystem functioning. Recent findings indicate that marine archaea and archaeal viruses are active and relevant components of marine microbial assemblages, far more abundant and diverse than was previously thought. Further research is urgently needed to better understand the impacts of global change on virus–archaea dynamics and how archaea and their viruses can interactively influence the ocean’s feedbacks on global change.
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Affiliation(s)
- Roberto Danovaro
- Stazione Zoologica Anton Dohrn, Villa Comunale, Naples, Italy.,Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Eugenio Rastelli
- Stazione Zoologica Anton Dohrn, Villa Comunale, Naples, Italy.,Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Cinzia Corinaldesi
- Department of Sciences and Engineering of Materials, Environment and Urbanistics, Polytechnic University of Marche, Ancona, Italy
| | - Michael Tangherlini
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Antonio Dell'Anno
- Department of Life and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
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117
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Coutinho FH, Silveira CB, Gregoracci GB, Thompson CC, Edwards RA, Brussaard CPD, Dutilh BE, Thompson FL. Marine viruses discovered via metagenomics shed light on viral strategies throughout the oceans. Nat Commun 2017; 8:15955. [PMID: 28677677 PMCID: PMC5504273 DOI: 10.1038/ncomms15955] [Citation(s) in RCA: 146] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Accepted: 05/12/2017] [Indexed: 12/19/2022] Open
Abstract
Marine viruses are key drivers of host diversity, population dynamics and biogeochemical cycling and contribute to the daily flux of billions of tons of organic matter. Despite recent advancements in metagenomics, much of their biodiversity remains uncharacterized. Here we report a data set of 27,346 marine virome contigs that includes 44 complete genomes. These outnumber all currently known phage genomes in marine habitats and include members of previously uncharacterized lineages. We designed a new method for host prediction based on co-occurrence associations that reveals these viruses infect dominant members of the marine microbiome such as Prochlorococcus and Pelagibacter. A negative association between host abundance and the virus-to-host ratio supports the recently proposed Piggyback-the-Winner model of reduced phage lysis at higher host densities. An analysis of the abundance patterns of viruses throughout the oceans revealed how marine viral communities adapt to various seasonal, temperature and photic regimes according to targeted hosts and the diversity of auxiliary metabolic genes.
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Affiliation(s)
- Felipe H. Coutinho
- Instituto de Biologia (IB), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro 21944970, Brazil
- Centre for Molecular and Biomolecular Informatics (CMBI), Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, Nijmegen 6500 HB, The Netherlands
- Theoretical Biology and Bioinformatics, Utrecht University (UU), Utrecht 3584 CH, The Netherlands
| | - Cynthia B. Silveira
- Instituto de Biologia (IB), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro 21944970, Brazil
- Biology Department, San Diego State University (SDSU), San Diego, California 92182, USA
| | - Gustavo B. Gregoracci
- Departamento de Ciências do Mar, Universidade Federal de São Paulo (UNIFESP), Baixada Santista 11070100, Brazil
| | - Cristiane C. Thompson
- Instituto de Biologia (IB), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro 21944970, Brazil
| | - Robert A. Edwards
- Biology Department, San Diego State University (SDSU), San Diego, California 92182, USA
| | - Corina P. D. Brussaard
- Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, and University of Utrecht, PO Box 59, 1790 AB Den Burg Texel, The Netherlands
- Department of Aquatic Microbiology, Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam, Amsterdam 1090 GE, The Netherlands
| | - Bas E. Dutilh
- Instituto de Biologia (IB), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro 21944970, Brazil
- Centre for Molecular and Biomolecular Informatics (CMBI), Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, Nijmegen 6500 HB, The Netherlands
- Theoretical Biology and Bioinformatics, Utrecht University (UU), Utrecht 3584 CH, The Netherlands
| | - Fabiano L. Thompson
- Instituto de Biologia (IB), Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro 21944970, Brazil
- Universidade Federal do Rio de Janeiro (UFRJ)/COPPE/SAGE, Rio de Janeiro 21941950, Brazil
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118
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Abstract
Viruses are incapable of autonomous energy production. Although many experimental studies make it clear that viruses are parasitic entities that hijack the molecular resources of the host, a detailed estimate for the energetic cost of viral synthesis is largely lacking. To quantify the energetic cost of viruses to their hosts, we enumerated the costs associated with two very distinct but representative DNA and RNA viruses, namely, T4 and influenza. We found that, for these viruses, translation of viral proteins is the most energetically expensive process. Interestingly, the costs of building a T4 phage and a single influenza virus are nearly the same. Due to influenza's higher burst size, however, the overall cost of a T4 phage infection is only 2-3% of the cost of an influenza infection. The costs of these infections relative to their host's estimated energy budget during the infection reveal that a T4 infection consumes about a third of its host's energy budget, whereas an influenza infection consumes only ≈ 1%. Building on our estimates for T4, we show how the energetic costs of double-stranded DNA phages scale with the capsid size, revealing that the dominant cost of building a virus can switch from translation to genome replication above a critical size. Last, using our predictions for the energetic cost of viruses, we provide estimates for the strengths of selection and genetic drift acting on newly incorporated genetic elements in viral genomes, under conditions of energy limitation.
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Affiliation(s)
- Gita Mahmoudabadi
- Department of Bioengineering, California Institute of Technology, Pasadena, CA 91125
| | - Ron Milo
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Rob Phillips
- Department of Bioengineering, California Institute of Technology, Pasadena, CA 91125;
- Department of Applied Physics, California Institute of Technology, Pasadena, CA 91125
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119
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Parmar KM, Gaikwad SL, Dhakephalkar PK, Kothari R, Singh RP. Intriguing Interaction of Bacteriophage-Host Association: An Understanding in the Era of Omics. Front Microbiol 2017; 8:559. [PMID: 28439260 PMCID: PMC5383658 DOI: 10.3389/fmicb.2017.00559] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 03/16/2017] [Indexed: 01/09/2023] Open
Abstract
Innovations in next-generation sequencing technology have introduced new avenues in microbial studies through “omics” approaches. This technology has considerably augmented the knowledge of the microbial world without isolation prior to their identification. With an enormous volume of bacterial “omics” data, considerable attempts have been recently invested to improve an insight into virosphere. The interplay between bacteriophages and their host has created a significant influence on the biogeochemical cycles, microbial diversity, and bacterial population regulation. This review highlights various concepts such as genomics, transcriptomics, proteomics, and metabolomics to infer the phylogenetic affiliation and function of bacteriophages and their impact on diverse microbial communities. Omics technologies illuminate the role of bacteriophage in an environment, the influences of phage proteins on the bacterial host and provide information about the genes important for interaction with bacteria. These investigations will reveal some of bio-molecules and biomarkers of the novel phage which demand to be unveiled.
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Affiliation(s)
| | | | | | - Ramesh Kothari
- Department of Biosciences, Saurashtra UniversityRajkot, India
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120
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EBV Infection and Glucose Metabolism in Nasopharyngeal Carcinoma. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1018:75-90. [DOI: 10.1007/978-981-10-5765-6_6] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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121
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Hassard F, Gwyther CL, Farkas K, Andrews A, Jones V, Cox B, Brett H, Jones DL, McDonald JE, Malham SK. Abundance and Distribution of Enteric Bacteria and Viruses in Coastal and Estuarine Sediments-a Review. Front Microbiol 2016; 7:1692. [PMID: 27847499 PMCID: PMC5088438 DOI: 10.3389/fmicb.2016.01692] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Accepted: 10/10/2016] [Indexed: 11/26/2022] Open
Abstract
The long term survival of fecal indicator organisms (FIOs) and human pathogenic microorganisms in sediments is important from a water quality, human health and ecological perspective. Typically, both bacteria and viruses strongly associate with particulate matter present in freshwater, estuarine and marine environments. This association tends to be stronger in finer textured sediments and is strongly influenced by the type and quantity of clay minerals and organic matter present. Binding to particle surfaces promotes the persistence of bacteria in the environment by offering physical and chemical protection from biotic and abiotic stresses. How bacterial and viral viability and pathogenicity is influenced by surface attachment requires further study. Typically, long-term association with surfaces including sediments induces bacteria to enter a viable-but-non-culturable (VBNC) state. Inherent methodological challenges of quantifying VBNC bacteria may lead to the frequent under-reporting of their abundance in sediments. The implications of this in a quantitative risk assessment context remain unclear. Similarly, sediments can harbor significant amounts of enteric viruses, however, the factors regulating their persistence remains poorly understood. Quantification of viruses in sediment remains problematic due to our poor ability to recover intact viral particles from sediment surfaces (typically <10%), our inability to distinguish between infective and damaged (non-infective) viral particles, aggregation of viral particles, and inhibition during qPCR. This suggests that the true viral titre in sediments may be being vastly underestimated. In turn, this is limiting our ability to understand the fate and transport of viruses in sediments. Model systems (e.g., human cell culture) are also lacking for some key viruses, preventing our ability to evaluate the infectivity of viruses recovered from sediments (e.g., norovirus). The release of particle-bound bacteria and viruses into the water column during sediment resuspension also represents a risk to water quality. In conclusion, our poor process level understanding of viral/bacterial-sediment interactions combined with methodological challenges is limiting the accurate source apportionment and quantitative microbial risk assessment for pathogenic organisms associated with sediments in aquatic environments.
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Affiliation(s)
| | - Ceri L. Gwyther
- Department of Engineering and Innovation, Open UniversityMilton Keynes, UK
| | - Kata Farkas
- School of Environment, Natural Resources and Geography, Bangor UniversityBangor, UK
| | | | | | | | | | - Davey L. Jones
- School of Environment, Natural Resources and Geography, Bangor UniversityBangor, UK
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