|
1
|
Hetta HF, Ahmed R, Ramadan YN, Fathy H, Khorshid M, Mabrouk MM, Hashem M. Gut virome: New key players in the pathogenesis of inflammatory bowel disease. World J Methodol 2025; 15:92592. [DOI: 10.5662/wjm.v15.i2.92592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 05/28/2024] [Accepted: 07/23/2024] [Indexed: 11/27/2024] Open
Abstract
Inflammatory bowel disease (IBD) is a chronic inflammatory illness of the intestine. While the mechanism underlying the pathogenesis of IBD is not fully understood, it is believed that a complex combination of host immunological response, environmental exposure, particularly the gut microbiota, and genetic susceptibility represents the major determinants. The gut virome is a group of viruses found in great frequency in the gastrointestinal tract of humans. The gut virome varies greatly among individuals and is influenced by factors including lifestyle, diet, health and disease conditions, geography, and urbanization. The majority of research has focused on the significance of gut bacteria in the progression of IBD, although viral populations represent an important component of the microbiome. We conducted this review to highlight the viral communities in the gut and their expected roles in the etiopathogenesis of IBD regarding published research to date.
Collapse
Affiliation(s)
- Helal F Hetta
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut 71515, Egypt
- Division of Microbiology, Immunology and Biotechnology, Faculty of pharmacy, University of Tabuk, Tabuk 71491, Saudi Arabia
| | - Rehab Ahmed
- Division of Microbiology, Immunology and Biotechnology, Department of Natural Products and Alternative Medicine, Faculty of Pharmacy, University of Tabuk, Tabuk 71491, Saudi Arabia
| | - Yasmin N Ramadan
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Assiut University, Assiut 71515, Egypt
| | - Hayam Fathy
- Department of Internal Medicine, Division Hepatogastroenterology, Assiut University, Assiut 71515, Egypt
| | - Mohammed Khorshid
- Department of Clinical Research, Egyptian Developers of Gastroenterology and Endoscopy Foundation, Cairo 11936, Egypt
| | - Mohamed M Mabrouk
- Department of Internal Medicine, Faculty of Medicine. Tanta University, Tanta 31527, Egypt
| | - Mai Hashem
- Department of Tropical Medicine, Gastroenterology and Hepatology, Assiut University Hospital, Assiut 71515, Egypt
| |
Collapse
|
|
2
|
Huisman JS, Bernhard A, Igler C. Should I stay or should I go: transmission trade-offs in phages and plasmids. Trends Microbiol 2025; 33:484-495. [PMID: 39979200 DOI: 10.1016/j.tim.2025.01.007] [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: 11/04/2024] [Revised: 01/13/2025] [Accepted: 01/15/2025] [Indexed: 02/22/2025]
Abstract
Mobile genetic elements (MGEs), like temperate bacteriophages and conjugative plasmids, are major vectors of virulence and antibiotic resistance in bacterial populations. For reproductive success, MGEs must balance horizontal and vertical transmission. Yet, the cost of horizontal transmission (metabolic burden or host death) puts these transmission modes at odds. Using virulence-transmission trade-off (VTT) theory, we identify three groups of environmental variables affecting the balance between horizontal and vertical transmission: host density, host physiology, and competitors. We find that general theoretical predictions of the optimal response to environmental cues align with experimental evidence on the regulation of transmission by phages and plasmids. We further highlight gaps between theory and experiments, differences between phages and plasmids, and suggest areas for future research.
Collapse
Affiliation(s)
- Jana S Huisman
- Physics of Living Systems, Massachusetts Institute of Technology, Cambridge, MA, USA.
| | - Andrina Bernhard
- Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland
| | - Claudia Igler
- Division of Evolution, Infection, and Genomics, School of Biological Sciences, University of Manchester, Manchester, UK
| |
Collapse
|
|
3
|
Al-Anany AM, Fatima R, Nair G, Mayol JT, Hynes AP. Temperate phage-antibiotic synergy across antibiotic classes reveals new mechanism for preventing lysogeny. mBio 2024; 15:e0050424. [PMID: 38757974 PMCID: PMC11237771 DOI: 10.1128/mbio.00504-24] [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: 02/21/2024] [Accepted: 04/18/2024] [Indexed: 05/18/2024] Open
Abstract
A recent demonstration of synergy between a temperate phage and the antibiotic ciprofloxacin suggested a scalable approach to exploiting temperate phages in therapy, termed temperate phage-antibiotic synergy, which specifically interacted with the lysis-lysogeny decision. To determine whether this would hold true across antibiotics, we challenged Escherichia coli with the phage HK97 and a set of 13 antibiotics spanning seven classes. As expected, given the conserved induction pathway, we observed synergy with classes of drugs known to induce an SOS response: a sulfa drug, other quinolones, and mitomycin C. While some β-lactams exhibited synergy, this appeared to be traditional phage-antibiotic synergy, with no effect on the lysis-lysogeny decision. Curiously, we observed a potent synergy with antibiotics not known to induce the SOS response: protein synthesis inhibitors gentamicin, kanamycin, tetracycline, and azithromycin. The synergy results in an eightfold reduction in the effective minimum inhibitory concentration of gentamicin, complete eradication of the bacteria, and, when administered at sub-optimal doses, drastically decreases the frequency of lysogens emerging from the combined challenge. However, lysogens exhibit no increased sensitivity to the antibiotic; synergy was maintained in the absence of RecA; and the antibiotic reduced the initial frequency of lysogeny rather than selecting against formed lysogens. Our results confirm that SOS-inducing antibiotics broadly result in temperate-phage-specific synergy, but that other antibiotics can interact with temperate phages specifically and result in synergy. This is the first report of a means of chemically blocking entry into lysogeny, providing a new means for manipulating the key lysis-lysogeny decision.IMPORTANCEThe lysis-lysogeny decision is made by most bacterial viruses (bacteriophages, phages), determining whether to kill their host or go dormant within it. With over half of the bacteria containing phages waiting to wake, this is one of the most important behaviors in all of biology. These phages are also considered unusable for therapy because of this behavior. In this paper, we show that many antibiotics bias this behavior to "wake" the dormant phages, forcing them to kill their host, but some also prevent dormancy in the first place. These will be important tools to study this critical decision point and may enable the therapeutic use of these phages.
Collapse
Affiliation(s)
- Amany M Al-Anany
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Rabia Fatima
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Gayatri Nair
- Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Jordan T Mayol
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Alexander P Hynes
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
- Department of Medicine, McMaster University, Hamilton, Ontario, Canada
- Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, Ontario, Canada
- Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| |
Collapse
|
|
4
|
Gilman RT, Muldoon MR, Megremis S, Robertson DL, Chanishvili N, Papadopoulos NG. Lysogeny destabilizes computationally simulated microbiomes. Ecol Lett 2024; 27:e14464. [PMID: 38923281 DOI: 10.1111/ele.14464] [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: 01/03/2024] [Revised: 05/06/2024] [Accepted: 06/06/2024] [Indexed: 06/28/2024]
Abstract
Microbiomes are ecosystems, and their stability can impact the health of their hosts. Theory predicts that predators influence ecosystem stability. Phages are key predators of bacteria in microbiomes, but phages are unusual predators because many have lysogenic life cycles. It has been hypothesized that lysogeny can destabilize microbiomes, but lysogeny has no direct analog in classical ecological theory, and no formal theory exists. We studied the stability of computationally simulated microbiomes with different numbers of temperate (lysogenic) and virulent (obligate lytic) phage species. Bacterial populations were more likely to fluctuate over time when there were more temperate phages species. After disturbances, bacterial populations returned to their pre-disturbance densities more slowly when there were more temperate phage species, but cycles engendered by disturbances dampened more slowly when there were more virulent phage species. Our work offers the first formal theory linking lysogeny to microbiome stability.
Collapse
Affiliation(s)
- R Tucker Gilman
- Department of Earth and Environmental Sciences, Faculty of Science and Engineering, University of Manchester, Manchester, UK
| | - Mark R Muldoon
- Department of Mathematics, Faculty of Science and Engineering, University of Manchester, Manchester, UK
| | - Spyridon Megremis
- Division of Infection, Immunity and Respiratory Medicine, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
- Department of Genetics and Genome Biology, Centre for Phage Research, Institute for Precision Health, University of Leicester, Leicester, UK
| | | | - Nina Chanishvili
- George Eliava Institute of Bacteriophages, Microbiology and Virology, Tbilisi, Georgia
- Ivane Javakhishvili Tbilisi State University, Tbilisi, Georgia
- NewVision University, Tbilisi, Georgia
| | - Nikolaos G Papadopoulos
- Allergy Department, 2nd Pediatric Clinic, University of Athens, Athens, Greece
- Lydia Becker Institute of Immunology and Inflammation, University of Manchester, Manchester, UK
| |
Collapse
|
|
5
|
Abadikhah M, Persson F, Farewell A, Wilén BM, Modin O. Viral diversity and host associations in microbial electrolysis cells. ISME COMMUNICATIONS 2024; 4:ycae143. [PMID: 39660013 PMCID: PMC11629682 DOI: 10.1093/ismeco/ycae143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2024] [Revised: 10/24/2024] [Accepted: 11/14/2024] [Indexed: 12/12/2024]
Abstract
In microbial electrolysis cells (MECs), microbial communities catalyze conversions between dissolved organic compounds, electrical energy, and energy carriers such as hydrogen and methane. Bacteria and archaea, which catalyze reactions on the anode and cathode of MECs, interact with phages; however, phage communities have previously not been examined in MECs. In this study, we used metagenomic sequencing to study prokaryotes and phages in nine MECs. A total of 852 prokaryotic draft genomes representing 278 species, and 1476 phage contigs representing 873 phage species were assembled. Among high quality prokaryotic genomes (>95% completion), 55% carried a prophage, and the three Desulfobacterota spp. that dominated the anode communities all carried prophages. Geobacter anodireducens, one of the bacteria dominating the anode communities, carried a CRISPR spacer showing evidence of a previous infection by a Peduoviridae phage present in the liquid of some MECs. Methanobacteriaceae spp. and an Acetobacterium sp., which dominated the cathodes, had several associations with Straboviridae spp. The results of this study show that phage communities in MECs are diverse and interact with functional microorganisms on both the anode and cathode.
Collapse
Affiliation(s)
- Marie Abadikhah
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Sven Hultins gata 6, SE-412 96 Gothenburg, Sweden
| | - Frank Persson
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Sven Hultins gata 6, SE-412 96 Gothenburg, Sweden
| | - Anne Farewell
- Department of Chemistry and Molecular Biology, University of Gothenburg, SE-405 30 Gothenburg, Sweden
| | - Britt-Marie Wilén
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Sven Hultins gata 6, SE-412 96 Gothenburg, Sweden
| | - Oskar Modin
- Division of Water Environment Technology, Department of Architecture and Civil Engineering, Chalmers University of Technology, Sven Hultins gata 6, SE-412 96 Gothenburg, Sweden
| |
Collapse
|
|
6
|
Hsieh SY, Savva GM, Telatin A, Tiwari SK, Tariq MA, Newberry F, Seton KA, Booth C, Bansal AS, Wileman T, Adriaenssens EM, Carding SR. Investigating the Human Intestinal DNA Virome and Predicting Disease-Associated Virus-Host Interactions in Severe Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). Int J Mol Sci 2023; 24:17267. [PMID: 38139096 PMCID: PMC10744171 DOI: 10.3390/ijms242417267] [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: 11/15/2023] [Revised: 11/27/2023] [Accepted: 11/30/2023] [Indexed: 12/24/2023] Open
Abstract
Understanding how the human virome, and which of its constituents, contributes to health or disease states is reliant on obtaining comprehensive virome profiles. By combining DNA viromes from isolated virus-like particles (VLPs) and whole metagenomes from the same faecal sample of a small cohort of healthy individuals and patients with severe myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), we have obtained a more inclusive profile of the human intestinal DNA virome. Key features are the identification of a core virome comprising tailed phages of the class Caudoviricetes, and a greater diversity of DNA viruses including extracellular phages and integrated prophages. Using an in silico approach, we predicted interactions between members of the Anaerotruncus genus and unique viruses present in ME/CFS microbiomes. This study therefore provides a framework and rationale for studies of larger cohorts of patients to further investigate disease-associated interactions between the intestinal virome and the bacteriome.
Collapse
Affiliation(s)
- Shen-Yuan Hsieh
- Food, Microbiome, and Health Research Programme, Quadram Institute Bioscience, Norwich Research Park, Norwich NR4 7UQ, UK; (S.-Y.H.); (A.T.); (S.K.T.); (M.A.T.); (F.N.); (K.A.S.); (T.W.)
| | - George M. Savva
- Core Science Resources, Quadram Institute Bioscience, Norwich NR4 7UQ, UK; (G.M.S.); (C.B.)
| | - Andrea Telatin
- Food, Microbiome, and Health Research Programme, Quadram Institute Bioscience, Norwich Research Park, Norwich NR4 7UQ, UK; (S.-Y.H.); (A.T.); (S.K.T.); (M.A.T.); (F.N.); (K.A.S.); (T.W.)
| | - Sumeet K. Tiwari
- Food, Microbiome, and Health Research Programme, Quadram Institute Bioscience, Norwich Research Park, Norwich NR4 7UQ, UK; (S.-Y.H.); (A.T.); (S.K.T.); (M.A.T.); (F.N.); (K.A.S.); (T.W.)
| | - Mohammad A. Tariq
- Food, Microbiome, and Health Research Programme, Quadram Institute Bioscience, Norwich Research Park, Norwich NR4 7UQ, UK; (S.-Y.H.); (A.T.); (S.K.T.); (M.A.T.); (F.N.); (K.A.S.); (T.W.)
| | - Fiona Newberry
- Food, Microbiome, and Health Research Programme, Quadram Institute Bioscience, Norwich Research Park, Norwich NR4 7UQ, UK; (S.-Y.H.); (A.T.); (S.K.T.); (M.A.T.); (F.N.); (K.A.S.); (T.W.)
| | - Katharine A. Seton
- Food, Microbiome, and Health Research Programme, Quadram Institute Bioscience, Norwich Research Park, Norwich NR4 7UQ, UK; (S.-Y.H.); (A.T.); (S.K.T.); (M.A.T.); (F.N.); (K.A.S.); (T.W.)
| | - Catherine Booth
- Core Science Resources, Quadram Institute Bioscience, Norwich NR4 7UQ, UK; (G.M.S.); (C.B.)
| | | | - Thomas Wileman
- Food, Microbiome, and Health Research Programme, Quadram Institute Bioscience, Norwich Research Park, Norwich NR4 7UQ, UK; (S.-Y.H.); (A.T.); (S.K.T.); (M.A.T.); (F.N.); (K.A.S.); (T.W.)
- Norwich Medical School, University of East Anglia, Norwich NR4 7TJ, UK
| | - Evelien M. Adriaenssens
- Food, Microbiome, and Health Research Programme, Quadram Institute Bioscience, Norwich Research Park, Norwich NR4 7UQ, UK; (S.-Y.H.); (A.T.); (S.K.T.); (M.A.T.); (F.N.); (K.A.S.); (T.W.)
| | - Simon R. Carding
- Food, Microbiome, and Health Research Programme, Quadram Institute Bioscience, Norwich Research Park, Norwich NR4 7UQ, UK; (S.-Y.H.); (A.T.); (S.K.T.); (M.A.T.); (F.N.); (K.A.S.); (T.W.)
- Norwich Medical School, University of East Anglia, Norwich NR4 7TJ, UK
| |
Collapse
|
|
7
|
Dougherty PE, Nielsen TK, Riber L, Lading HH, Forero-Junco LM, Kot W, Raaijmakers JM, Hansen LH. Widespread and largely unknown prophage activity, diversity, and function in two genera of wheat phyllosphere bacteria. THE ISME JOURNAL 2023; 17:2415-2425. [PMID: 37919394 PMCID: PMC10689766 DOI: 10.1038/s41396-023-01547-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 10/11/2023] [Accepted: 10/16/2023] [Indexed: 11/04/2023]
Abstract
Environmental bacteria host an enormous number of prophages, but their diversity and natural functions remain largely elusive. Here, we investigate prophage activity and diversity in 63 Erwinia and Pseudomonas strains isolated from flag leaves of wheat grown in a single field. Introducing and validating Virion Induction Profiling Sequencing (VIP-Seq), we identify and quantify the activity of 120 spontaneously induced prophages, discovering that some phyllosphere bacteria produce more than 108 virions/mL in overnight cultures, with significant induction also observed in planta. Sequence analyses and plaque assays reveal E. aphidicola prophages contribute a majority of intraspecies genetic diversity and divide their bacterial hosts into antagonistic factions engaged in widespread microbial warfare, revealing the importance of prophage-mediated microdiversity. When comparing spontaneously active prophages with predicted prophages we also find insertion sequences are strongly correlated with non-active prophages. In conclusion, we discover widespread and largely unknown prophage diversity and function in phyllosphere bacteria.
Collapse
Affiliation(s)
- Peter Erdmann Dougherty
- Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Tue Kjærgaard Nielsen
- Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Leise Riber
- Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Helen Helgå Lading
- Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | | | - Witold Kot
- Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Jos M Raaijmakers
- Department of Microbial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands
| | - Lars Hestbjerg Hansen
- Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark.
| |
Collapse
|
|
8
|
Sutcliffe SG, Reyes A, Maurice CF. Bacteriophages playing nice: Lysogenic bacteriophage replication stable in the human gut microbiota. iScience 2023; 26:106007. [PMID: 36798434 PMCID: PMC9926308 DOI: 10.1016/j.isci.2023.106007] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 10/28/2022] [Accepted: 01/13/2023] [Indexed: 01/19/2023] Open
Abstract
Bacteriophages, viruses specific to bacteria, coexist with their bacterial hosts with limited diversity fluctuations in the guts of healthy individuals where they replicate mostly via lysogenic replication. This favors 'piggy-back-the-winner' over 'kill-the-winner' dynamics which are driven by lytic bacteriophage replication. Revisiting the deep-viral sequencing data of a healthy individual sampled over 2.4 years, we explore how these dynamics occur. Prophages found in assembled bacterial metagenomes were also found extra-cellularly, as induced phage particles (iPPs), likely derived from prophage activation. These iPPs were diverse and continually present in low abundance, relative to the highly abundant but less diverse lytic phage population. The continuous detection of low levels of iPPs suggests that spontaneous induction regularly occurs in this healthy individual, possibly allowing prophages to maintain their ability to replicate and avoiding degradation and loss from the gut microbiota.
Collapse
Affiliation(s)
- Steven G. Sutcliffe
- McGill Centre for Microbiome Research, McGill University, Montreal, QC, Canada,Department of Microbiology & Immunology, McGill University, Montreal, QC, Canada
| | - Alejandro Reyes
- Max Planck Tandem Group in Computational Biology, Department of Biological Sciences, Universidad de los Andes, Bogotá 111711, Colombia,The Edison Family Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St Louis, MO, USA,Corresponding author
| | - Corinne F. Maurice
- McGill Centre for Microbiome Research, McGill University, Montreal, QC, Canada,Department of Microbiology & Immunology, McGill University, Montreal, QC, Canada,Corresponding author
| |
Collapse
|
|
9
|
Jansen D, Matthijnssens J. The Emerging Role of the Gut Virome in Health and Inflammatory Bowel Disease: Challenges, Covariates and a Viral Imbalance. Viruses 2023; 15:173. [PMID: 36680214 PMCID: PMC9861652 DOI: 10.3390/v15010173] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 01/03/2023] [Accepted: 01/05/2023] [Indexed: 01/11/2023] Open
Abstract
Virome research is a rapidly growing area in the microbiome field that is increasingly associated with human diseases, such as inflammatory bowel disease (IBD). Although substantial progress has been made, major methodological challenges limit our understanding of the virota. In this review, we describe challenges that must be considered to accurately report the virome composition and the current knowledge on the virome in health and IBD. First, the description of the virome shows strong methodological biases related to wetlab (e.g., VLP enrichment) and bioinformatics approaches (viral identification and classification). Second, IBD patients show consistent viral imbalances characterized by a high relative abundance of phages belonging to the Caudovirales and a low relative abundance of phages belonging to the Microviridae. Simultaneously, a sporadic contraction of CrAss-like phages and a potential expansion of the lysogenic potential of the intestinal virome are observed. Finally, despite numerous studies that have conducted diversity analysis, it is difficult to draw firm conclusions due to methodological biases. Overall, we present the many methodological and environmental factors that influence the virome, its current consensus in health and IBD, and a contributing hypothesis called the "positive inflammatory feedback loop" that may play a role in the pathophysiology of IBD.
Collapse
Affiliation(s)
| | - Jelle Matthijnssens
- Laboratory of Viral Metagenomics, Rega Institute, Department of Microbiology, Immunology and Transplantation, University of Leuven, B-3000 Leuven, Belgium
| |
Collapse
|
|
10
|
Growth Substrate and Prophage Induction Collectively Influence Metabolite and Lipid Profiles in a Marine Bacterium. mSystems 2022; 7:e0058522. [PMID: 35972149 PMCID: PMC9600351 DOI: 10.1128/msystems.00585-22] [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: 12/24/2022] Open
Abstract
Bacterial growth substrates influence a variety of biological functions, including the biosynthesis and regulation of lipid intermediates. The extent of this rewiring is not well understood nor has it been considered in the context of virally infected cells. Here, we used a one-host-two-temperate phage model system to probe the combined influence of growth substrate and phage infection on host carbon and lipid metabolism. Using untargeted metabolomics and lipidomics, we reported the detection of a suite of metabolites and lipid classes for two Sulfitobacter lysogens provided with three growth substrates of differing complexity and nutrient composition (yeast extract/tryptone [complex], glutamate and acetate). The growth medium led to dramatic differences in the detectable intracellular metabolites, with only 15% of 175 measured metabolites showing overlap across the three growth substrates. Between-strain differences were most evident in the cultures grown on acetate, followed by glutamate then complex medium. Lipid distribution profiles were also distinct between cultures grown on different substrates as well as between the two lysogens grown in the same medium. Five phospholipids, three aminolipid, and one class of unknown lipid-like features were identified. Most (≥94%) of these 75 lipids were quantifiable in all samples. Metabolite and lipid profiles were strongly determined by growth medium composition and modestly by strain type. Because fluctuations in availability and form of carbon substrates and nutrients, as well as virus pressure, are common features of natural systems, the influence of these intersecting factors will undoubtedly be imprinted in the metabolome and lipidome of resident bacteria. IMPORTANCE Community-level metabolomics approaches are increasingly used to characterize natural microbial populations. These approaches typically depend upon temporal snapshots from which the status and function of communities are often inferred. Such inferences are typically drawn from lab-based studies of select model organisms raised under limited growth conditions. To better interpret community-level data, the extent to which ecologically relevant bacteria demonstrate metabolic flexibility requires elucidation. Herein, we used an environmentally relevant model heterotrophic marine bacterium to assess the relationship between growth determinants and metabolome. We also aimed to assess the contribution of phage activity to the host metabolome. Striking differences in primary metabolite and lipid profiles appeared to be driven primarily by growth regime and, secondarily, by phage type. These findings demonstrated the malleable nature of metabolomes and lipidomes and lay the foundation for future studies that relate cellular composition with function in complex environmental microbial communities.
Collapse
|
|
11
|
Liang G, Gao H, Bushman FD. The pediatric virome in health and disease. Cell Host Microbe 2022; 30:639-649. [PMID: 35550667 DOI: 10.1016/j.chom.2022.04.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 03/22/2022] [Accepted: 04/11/2022] [Indexed: 11/03/2022]
Abstract
Associations between the global microbiome and diseases of children have been studied extensively; however, research on the viral component of the microbiome, the "virome," is less advanced. The analysis of disease associations with the virome is often technically challenging, requiring a close examination of the "virome dark matter." The gut is a particularly rich source of viral particles, and now multiple studies have reported intriguing associations of the virome with childhood diseases. For example, virome studies have elucidated new lineages of gut viruses that appear to be tightly associated with childhood diarrhea, and consistent patterns are starting to emerge from virome studies in pediatric IBD. In this review, we summarize the methods for studying the virome and recent research on the nature of the virome during childhood, focusing on specific studies of the intestinal virome in pediatric diseases.
Collapse
Affiliation(s)
- Guanxiang Liang
- Center for Infectious Disease Research, School of Medicine, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Center for Life Sciences, Beijing 100084, China.
| | - Hongyan Gao
- Center for Infectious Disease Research, School of Medicine, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Center for Life Sciences, Beijing 100084, China
| | - Frederic D Bushman
- Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6076, USA.
| |
Collapse
|
|
12
|
Abstract
Bacteriophages are the most diverse and abundant biological entities on the Earth and require host bacteria to replicate. Because of this obligate relationship, in addition to the challenging conditions of surrounding environments, phages must integrate information about extrinsic and intrinsic factors when infecting their host. This integration helps to determine whether the infection becomes lytic or lysogenic, which likely influences phage spreading and long-term survival. Although a variety of environmental and physiological clues are known to modulate lysis-lysogeny decisions, the social interplay among phages and host populations has been overlooked until recently. A growing body of evidence indicates that cell-cell communication in bacteria and, more recently, peptide-based communication among phage-phage populations, affect phage-host interactions by controlling phage lysis-lysogeny decisions and phage counter-defensive strategies in bacteria. Here, we explore and discuss the role of signal molecules as well as quorum sensing and quenching factors that mediate phage-host interactions. Our aim is to provide an overview of population-dependent mechanisms that influence phage replication, and how social communication may affect the dynamics and evolution of microbial communities, including their implications in phage therapy.
Collapse
|
|
13
|
Temperate phage-antibiotic synergy eradicates bacteria through depletion of lysogens. Cell Rep 2021; 35:109172. [PMID: 34038739 DOI: 10.1016/j.celrep.2021.109172] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 03/13/2021] [Accepted: 05/04/2021] [Indexed: 01/02/2023] Open
Abstract
There is renewed interest in bacterial viruses (phages) as alternatives to antibiotics. All phage treatments to date have used virulent phages rather than temperate ones, as these can integrate into the genome of the bacterial host and lie dormant. However, temperate phages are abundant and easier to isolate. To make use of these entities, we leverage stressors known to awaken these dormant, integrated phages. Co-administration of the temperate phage HK97 with sub-inhibitory concentrations of the antibiotic ciprofloxacin results in bacterial eradication (≥8 log reduction) in vitro. This synergy is mechanistically distinct from phage-antibiotic-synergy described for virulent phages. Instead, the antibiotic specifically selects against bacteria in which the phage has integrated. As the interaction between temperate phages and stressors such as ciprofloxacin are known to be widespread, this approach may be broadly applicable and enable the use of temperate phages to combat bacterial infections.
Collapse
|
|
14
|
Topka-Bielecka G, Bloch S, Nejman-Faleńczyk B, Grabski M, Jurczak-Kurek A, Górniak M, Dydecka A, Necel A, Węgrzyn G, Węgrzyn A. Characterization of the Bacteriophage vB_EfaS-271 Infecting Enterococcus faecalis. Int J Mol Sci 2020; 21:ijms21176345. [PMID: 32882938 PMCID: PMC7503890 DOI: 10.3390/ijms21176345] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/28/2020] [Accepted: 08/31/2020] [Indexed: 12/11/2022] Open
Abstract
A newly isolated bacteriophage infecting Enterococcus faecalis strains has been characterized, including determination of its molecular features. This phage, named vB_EfaS-271, has been classified as a Siphoviridae member, according to electron microscopy characterization of the virions, composed of a 50 nm-diameter head and a long, flexible, noncontractable tail (219 × 12.5 nm). Analysis of the whole dsDNA genome of this phage showed that it consists of 40,197 bp and functional modules containing genes coding for proteins that are involved in DNA replication (including DNA polymerase/primase), morphogenesis, packaging and cell lysis. Mass spectrometry analysis allowed us to identify several phage-encoded proteins. vB_EfaS-271 reveals a relatively narrow host range, as it is able to infect only a few E. faecalis strains. On the other hand, it is a virulent phage (unable to lysogenize host cells), effectively and quickly destroying cultures of sensitive host bacteria, with a latent period as short as 8 min and burst size of approximately 70 phages per cell at 37 °C. This phage was also able to destroy biofilms formed by E. faecalis. These results contribute to our understanding of the biodiversity of bacteriophages, confirming the high variability among these viruses and indicating specific genetic and functional features of vB_EfaS-271.
Collapse
Affiliation(s)
- Gracja Topka-Bielecka
- Department of Molecular Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland; (G.T.-B.); (B.N.-F.); (M.G.); (A.D.); (A.N.); (G.W.)
| | - Sylwia Bloch
- Laboratory of Molecular Biology, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Kładki 24, 80-822 Gdansk, Poland;
| | - Bożena Nejman-Faleńczyk
- Department of Molecular Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland; (G.T.-B.); (B.N.-F.); (M.G.); (A.D.); (A.N.); (G.W.)
| | - Michał Grabski
- Department of Molecular Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland; (G.T.-B.); (B.N.-F.); (M.G.); (A.D.); (A.N.); (G.W.)
- Laboratory of Marine Biogeochemistry, Institute of Oceanology, Polish Academy of Sciences, Powstańców Warszawy 55, 81-712 Sopot, Poland
| | - Agata Jurczak-Kurek
- Department of Molecular Evolution, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland; (A.J.-K.); (M.G.)
| | - Marcin Górniak
- Department of Molecular Evolution, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland; (A.J.-K.); (M.G.)
| | - Aleksandra Dydecka
- Department of Molecular Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland; (G.T.-B.); (B.N.-F.); (M.G.); (A.D.); (A.N.); (G.W.)
| | - Agnieszka Necel
- Department of Molecular Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland; (G.T.-B.); (B.N.-F.); (M.G.); (A.D.); (A.N.); (G.W.)
| | - Grzegorz Węgrzyn
- Department of Molecular Biology, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland; (G.T.-B.); (B.N.-F.); (M.G.); (A.D.); (A.N.); (G.W.)
| | - Alicja Węgrzyn
- Laboratory of Molecular Biology, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Kładki 24, 80-822 Gdansk, Poland;
- Correspondence: ; Tel.: +48-58-523-6040
| |
Collapse
|
|
15
|
Quigley LNM, Edwards A, Steen AD, Buchan A. Characterization of the Interactive Effects of Labile and Recalcitrant Organic Matter on Microbial Growth and Metabolism. Front Microbiol 2019; 10:493. [PMID: 30941109 PMCID: PMC6433851 DOI: 10.3389/fmicb.2019.00493] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 02/26/2019] [Indexed: 11/23/2022] Open
Abstract
Geochemical models typically represent organic matter (OM) as consisting of multiple, independent pools of compounds, each accessed by microorganisms at different rates. However, recent findings indicate that organic compounds can interact within microbial metabolisms. The relevance of interactive effects within marine systems is debated and a mechanistic understanding of its complexities, including microbe-substrate relationships, is lacking. As a first step toward uncovering mediating processes, the interactive effects of distinct pools of OM on the growth and respiration of marine bacteria, individual strains and a simple, constructed community of Roseobacter lineage members were tested. Isolates were provided with natural organic matter (NOM) and different concentrations (1, 4, 40, 400 μM-C) and forms of labile OM (acetate, casamino acids, tryptone, coumarate). The microbial response to the mixed substrate regimes was assessed using viable counts and respiration in two separate experiments. Two marine bacteria and a six-member constructed community were assayed with these experiments. Both synergistic and antagonistic growth responses were evident for all strains, but all were transient. The specific substrate conditions promoting a response, and the direction of that response, varied amongst species. These findings indicate that the substrate conditions that result in OM interactive effects are both transient and species-specific and thus influenced by both the composition and metabolic potential of a microbial community.
Collapse
Affiliation(s)
- Lauren N M Quigley
- Department of Microbiology, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Abigail Edwards
- Department of Microbiology, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Andrew D Steen
- Department of Earth and Planetary Sciences, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Alison Buchan
- Department of Microbiology, The University of Tennessee, Knoxville, Knoxville, TN, United States
| |
Collapse
|
|
16
|
Jacquiod S, Nunes I, Brejnrod A, Hansen MA, Holm PE, Johansen A, Brandt KK, Priemé A, Sørensen SJ. Long-term soil metal exposure impaired temporal variation in microbial metatranscriptomes and enriched active phages. MICROBIOME 2018; 6:223. [PMID: 30545417 PMCID: PMC6292020 DOI: 10.1186/s40168-018-0606-1] [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: 09/03/2018] [Accepted: 11/25/2018] [Indexed: 05/13/2023]
Abstract
BACKGROUND It remains unclear whether adaptation and changes in diversity associated to a long-term perturbation are sufficient to ensure functional resilience of soil microbial communities. We used RNA-based approaches (16S rRNA gene transcript amplicon coupled to shotgun mRNA sequencing) to study the legacy effects of a century-long soil copper (Cu) pollution on microbial activity and composition, as well as its effect on the capacity of the microbial community to react to temporal fluctuations. RESULTS Despite evidence of microbial adaptation (e.g., iron homeostasis and avoidance/resistance strategies), increased heterogeneity and richness loss in transcribed gene pools were observed with increasing soil Cu, together with an unexpected predominance of phage mRNA signatures. Apparently, phage activation was either triggered directly by Cu, or indirectly via enhanced expression of DNA repair/SOS response systems in Cu-exposed bacteria. Even though total soil carbon and nitrogen had accumulated with increasing Cu, a reduction in temporally induced mRNA functions was observed. Microbial temporal response groups (TRGs, groups of microbes with a specific temporal response) were heavily affected by Cu, both in abundance and phylogenetic composition. CONCLUSION Altogether, results point toward a Cu-mediated "decoupling" between environmental fluctuations and microbial activity, where Cu-exposed microbes stopped fulfilling their expected contributions to soil functioning relative to the control. Nevertheless, some functions remained active in February despite Cu, concomitant with an increase in phage mRNA signatures, highlighting that somehow, microbial activity is still happening under these adverse conditions.
Collapse
Affiliation(s)
- Samuel Jacquiod
- Section of Microbiology, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen, Denmark
- Agroécologie, AgroSup Dijon, INRA, Univ Bourgogne Franche-Comté, 17 rue Sully, 21000, Dijon, France
| | - Inês Nunes
- Section of Microbiology, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen, Denmark
- Present address: Microbe Technology Department, Novozymes A/S, Krogshoejvej 36, 2880, Bagsværd, Denmark
| | - Asker Brejnrod
- Section of Microbiology, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen, Denmark
- Present address: Center for Basic Metabolic Research, University of Copenhagen, Blegdamsvej 3A, 2200, Copenhagen, Denmark
| | - Martin A Hansen
- Section of Microbiology, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen, Denmark
| | - Peter E Holm
- Present address: Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark
| | - Anders Johansen
- Department of Environmental Science, Aarhus University, Frederiksborgvej 399, 4000, Roskilde, Denmark
| | - Kristian K Brandt
- Present address: Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark
| | - Anders Priemé
- Section of Microbiology, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen, Denmark
| | - Søren J Sørensen
- Section of Microbiology, University of Copenhagen, Universitetsparken 15, 2100, Copenhagen, Denmark.
| |
Collapse
|
|
17
|
Štveráková D, Šedo O, Benešík M, Zdráhal Z, Doškař J, Pantůček R. Rapid Identification of Intact Staphylococcal Bacteriophages Using Matrix-Assisted Laser Desorption Ionization-Time-of-Flight Mass Spectrometry. Viruses 2018; 10:v10040176. [PMID: 29617332 PMCID: PMC5923470 DOI: 10.3390/v10040176] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 04/01/2018] [Accepted: 04/02/2018] [Indexed: 12/31/2022] Open
Abstract
Staphylococcus aureus is a major causative agent of infections associated with hospital environments, where antibiotic-resistant strains have emerged as a significant threat. Phage therapy could offer a safe and effective alternative to antibiotics. Phage preparations should comply with quality and safety requirements; therefore, it is important to develop efficient production control technologies. This study was conducted to develop and evaluate a rapid and reliable method for identifying staphylococcal bacteriophages, based on detecting their specific proteins using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) profiling that is among the suggested methods for meeting the regulations of pharmaceutical authorities. Five different phage purification techniques were tested in combination with two MALDI-TOF MS matrices. Phages, either purified by CsCl density gradient centrifugation or as resuspended phage pellets, yielded mass spectra with the highest information value if ferulic acid was used as the MALDI matrix. Phage tail and capsid proteins yielded the strongest signals whereas the culture conditions had no effect on mass spectral quality. Thirty-seven phages from Myoviridae, Siphoviridae or Podoviridae families were analysed, including 23 siphophages belonging to the International Typing Set for human strains of S. aureus, as well as phages in preparations produced by Microgen, Bohemia Pharmaceuticals and MB Pharma. The data obtained demonstrate that MALDI-TOF MS can be used to effectively distinguish between Staphylococcus-specific bacteriophages.
Collapse
Affiliation(s)
- Dana Štveráková
- Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic.
| | - Ondrej Šedo
- Central European Institute of Technology, Masaryk University, Kamenice 5, 62500 Brno, Czech Republic.
| | - Martin Benešík
- Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic.
| | - Zbyněk Zdráhal
- Central European Institute of Technology, Masaryk University, Kamenice 5, 62500 Brno, Czech Republic.
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, Kamenice 5, 62500 Brno, Czech Republic.
| | - Jiří Doškař
- Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic.
| | - Roman Pantůček
- Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic.
| |
Collapse
|
|
18
|
Balikó G, Vernyik V, Karcagi I, Györfy Z, Draskovits G, Fehér T, Pósfai G. Rational Efforts to Streamline the Escherichia coliGenome. Synth Biol (Oxf) 2018. [DOI: 10.1002/9783527688104.ch4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Gabriella Balikó
- Biological Research Centre of the Hungarian Academy of Sciences; Institute of Biochemistry, Synthetic and Systems Biology Unit; Temesvari krt. 62 Szeged 6726 Hungary
| | - Viktor Vernyik
- Biological Research Centre of the Hungarian Academy of Sciences; Institute of Biochemistry, Synthetic and Systems Biology Unit; Temesvari krt. 62 Szeged 6726 Hungary
| | - Ildikó Karcagi
- Biological Research Centre of the Hungarian Academy of Sciences; Institute of Biochemistry, Synthetic and Systems Biology Unit; Temesvari krt. 62 Szeged 6726 Hungary
| | - Zsuzsanna Györfy
- Biological Research Centre of the Hungarian Academy of Sciences; Institute of Biochemistry, Synthetic and Systems Biology Unit; Temesvari krt. 62 Szeged 6726 Hungary
| | - Gábor Draskovits
- Biological Research Centre of the Hungarian Academy of Sciences; Institute of Biochemistry, Synthetic and Systems Biology Unit; Temesvari krt. 62 Szeged 6726 Hungary
| | - Tamás Fehér
- Biological Research Centre of the Hungarian Academy of Sciences; Institute of Biochemistry, Synthetic and Systems Biology Unit; Temesvari krt. 62 Szeged 6726 Hungary
| | - György Pósfai
- Biological Research Centre of the Hungarian Academy of Sciences; Institute of Biochemistry, Synthetic and Systems Biology Unit; Temesvari krt. 62 Szeged 6726 Hungary
| |
Collapse
|
|
19
|
Lysogeny in nature: mechanisms, impact and ecology of temperate phages. ISME JOURNAL 2017; 11:1511-1520. [PMID: 28291233 DOI: 10.1038/ismej.2017.16] [Citation(s) in RCA: 457] [Impact Index Per Article: 57.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 12/04/2016] [Accepted: 01/19/2017] [Indexed: 01/07/2023]
Abstract
Viruses that infect bacteria (phages) can influence bacterial community dynamics, bacterial genome evolution and ecosystem biogeochemistry. These influences differ depending on whether phages establish lytic, chronic or lysogenic infections. Although the first two produce virion progeny, with lytic infections resulting in cell destruction, phages undergoing lysogenic infections replicate with cells without producing virions. The impacts of lysogeny are numerous and well-studied at the cellular level, but ecosystem-level consequences remain underexplored compared to those of lytic infections. Here, we review lysogeny from molecular mechanisms to ecological patterns to emerging approaches of investigation. Our goal is to highlight both its diversity and importance in complex communities. Altogether, using a combined viral ecology toolkit that is applied across broad model systems and environments will help us understand more of the diverse lifestyles and ecological impacts of lysogens in nature.
Collapse
|
|
20
|
Srinivasiah S, Lovett J, Ghosh D, Roy K, Fuhrmann JJ, Radosevich M, Wommack KE. Dynamics of autochthonous soil viral communities parallels dynamics of host communities under nutrient stimulation. FEMS Microbiol Ecol 2015; 91:fiv063. [PMID: 26149131 DOI: 10.1093/femsec/fiv063] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/03/2015] [Indexed: 11/14/2022] Open
Abstract
Viruses are highly abundant in soils with their numbers exceeding those of cooccurring bacterial cells by 10- to over 1000-fold. Water and organic matter content influence the magnitude of the viral-to-bacterial ratio in soils; thus, ecosystem type and land use shape interactions between viral and host microbial communities in soils. Less understood are the shorter term interactions between viral and host communities that ultimately maintain the large viral standing stock within soils. This study examined short-term dynamics of viral and bacterial communities in soils to determine whether the growth of soil bacterial communities results in the production of soil viruses, and if viral community responses occur within specific populations. In microcosms amended with different carbon sources, increases in viral abundance (VA) accompanied increases in bacterial abundance (BA) and bacterial respiration rate (BRR). The timing and intensity of increases in BA, VA and BRR were different across C sources suggesting differences in the predominant mode of viral replication within growth-stimulated bacterial populations. Moreover, compositional changes occurred in soil bacterial and viral communities indicating that new viral production arose from a subset of host populations. To our knowledge, these are the first observations of soil viral populations responding to short-term changes in soil bacterial communities.
Collapse
Affiliation(s)
- Sharath Srinivasiah
- Delaware Biotechnology Institute, University of Delaware, 15 Innovation Way, Newark, DE 19711, USA
| | - Jacqueline Lovett
- Delaware Biotechnology Institute, University of Delaware, 15 Innovation Way, Newark, DE 19711, USA
| | - Dhritiman Ghosh
- Biosystems Engineering & Soil Science Department, University of Tennessee, Knoxville, TN 37996 USA
| | - Krishnakali Roy
- Biosystems Engineering & Soil Science Department, University of Tennessee, Knoxville, TN 37996 USA
| | - Jeffry J Fuhrmann
- Department of Plant and Soil Sciences, University of Delaware, Newark, DE 19716, USA
| | - Mark Radosevich
- Biosystems Engineering & Soil Science Department, University of Tennessee, Knoxville, TN 37996 USA
| | - K Eric Wommack
- Delaware Biotechnology Institute, University of Delaware, 15 Innovation Way, Newark, DE 19711, USA Department of Plant and Soil Sciences, University of Delaware, Newark, DE 19716, USA
| |
Collapse
|
|
21
|
Impact of spontaneous prophage induction on the fitness of bacterial populations and host-microbe interactions. J Bacteriol 2014; 197:410-9. [PMID: 25404701 DOI: 10.1128/jb.02230-14] [Citation(s) in RCA: 196] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Bacteriophages and genetic elements, such as prophage-like elements, pathogenicity islands, and phage morons, make up a considerable amount of bacterial genomes. Their transfer and subsequent activity within the host's genetic circuitry have had a significant impact on bacterial evolution. In this review, we consider what underlying mechanisms might cause the spontaneous activity of lysogenic phages in single bacterial cells and how the spontaneous induction of prophages can lead to competitive advantages for and influence the lifestyle of bacterial populations or the virulence of pathogenic strains.
Collapse
|
|
22
|
Cenens W, Makumi A, Mebrhatu MT, Lavigne R, Aertsen A. Phage-host interactions during pseudolysogeny: Lessons from the Pid/dgo interaction. BACTERIOPHAGE 2013; 3:e25029. [PMID: 23819109 PMCID: PMC3694060 DOI: 10.4161/bact.25029] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 04/13/2013] [Revised: 05/06/2013] [Accepted: 05/13/2013] [Indexed: 12/11/2022]
Abstract
Although the study of phage infection has a long history and catalyzed much of our current understanding in bacterial genetics, molecular biology, evolution and ecology, it seems that microbiologists have only just begun to explore the intricacy of phage-host interactions. In a recent manuscript by Cenens et al. we found molecular and genetic support for pseudolysogenic development in the Salmonella Typhimurium-phage P22 model system. More specifically, we observed the existence of phage carrier cells harboring an episomal P22 element that segregated asymmetrically upon subsequent divisions. Moreover, a newly discovered P22 ORFan protein (Pid) able to derepress a metabolic operon of the host (dgo) proved to be specifically expressed in these phage carrier cells. In this addendum we expand on our view regarding pseudolysogeny and its effects on bacterial and phage biology.
Collapse
Affiliation(s)
- William Cenens
- Laboratory of Food Microbiology; Department of Microbial and Molecular Systems (M2S); Faculty of Bioscience Engineering; KU Leuven; Leuven, Belgium
| | - Angella Makumi
- Laboratory of Food Microbiology; Department of Microbial and Molecular Systems (M2S); Faculty of Bioscience Engineering; KU Leuven; Leuven, Belgium
| | - Mehari Tesfazgi Mebrhatu
- Laboratory of Food Microbiology; Department of Microbial and Molecular Systems (M2S); Faculty of Bioscience Engineering; KU Leuven; Leuven, Belgium
| | - Rob Lavigne
- Laboratory of Gene Technology; Department of Biosystems; Faculty of Bioscience Engineering; KU Leuven; Leuven, Belgium
| | - Abram Aertsen
- Laboratory of Food Microbiology; Department of Microbial and Molecular Systems (M2S); Faculty of Bioscience Engineering; KU Leuven; Leuven, Belgium
| |
Collapse
|
|
23
|
Keen EC. Paradigms of pathogenesis: targeting the mobile genetic elements of disease. Front Cell Infect Microbiol 2012; 2:161. [PMID: 23248780 PMCID: PMC3522046 DOI: 10.3389/fcimb.2012.00161] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Accepted: 11/30/2012] [Indexed: 11/13/2022] Open
Affiliation(s)
- Eric C Keen
- Department of Biology, University of Miami Coral Gables, FL, USA.
| |
Collapse
|
|
24
|
Nirmal Kumar GP, Sundarrajan S, Paul VD, Nandini S, Saravanan RS, Hariharan S, Sriram B, Padmanabhan S. Use of prophage free host for achieving homogenous population of bacteriophages: new findings. Virus Res 2012; 169:182-7. [PMID: 22917718 DOI: 10.1016/j.virusres.2012.07.026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2012] [Revised: 07/18/2012] [Accepted: 07/24/2012] [Indexed: 01/21/2023]
Abstract
We demonstrate that the prophage status of bacteria plays a critical role in achieving homogenous population of a phage preparation. When a lytic Staphylococcus bacteriophage 44AHJD was propagated in a Staphylococcus clinical isolate, the enriched phage showed 44AHJD phage virions along with the released prophages from the baiting host. The released prophage was identified as a siphophage by transmission electron microscopy. To obtain a phage preparation free of prophages, when we carried out multiplication of the 44AHJD phage in a prophage free Staphyloccoccus aureus host namely RN4220, we were surprised not to see any phage plaques in spite of the phage exhibiting >99.9% adsorption to such cells. Since RN4220 host is devoid of restriction modification system and prophages, we hypothesized that in spite of successful infection and multiplication, the phage virions might have failed to show plaques due to its insignificant release from the cell possibly due to insufficient endolysin expressed from phage virions during phage development and assembly. Our hypothesis was confirmed when we observed plaques of 44AHJD phage in RN4220 cells where additional phage endolysin protein was supplemented via a plasmid. Endolysin protein from various types of Staphylococcus phages showed plaques of 44AHJD in RN4220 cells confirming our hypothesis. Also, we demonstrate for the first time that propagation of 44AHJD phage with endolysin supplementation in prophage free RN4220 host yields pure phage preparation.
Collapse
Affiliation(s)
- G P Nirmal Kumar
- Gangagen Biotechnologies Pvt Ltd, No 12, 5th Cross, Raghavendra Layout, Opp MEI Ltd, Tumkur Road, Yeshwantpur, Bangalore 560022, India
| | | | | | | | | | | | | | | |
Collapse
|
|
25
|
Nejman-Faleńczyk B, Golec P, Maciąg M, Wegrzyn A, Węgrzyn G. Inhibition of development of Shiga toxin-converting bacteriophages by either treatment with citrate or amino acid starvation. Foodborne Pathog Dis 2011; 9:13-9. [PMID: 22047055 DOI: 10.1089/fpd.2011.0980] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
OBJECTIVES Shiga toxin-producing Escherichia coli (STEC) are pathogenic strains, whose virulence depends on induction of Shiga toxin-converting prophages and their subsequent lytic development. We explored which factors or conditions could inhibit development of these phages, potentially decreasing virulence of STEC. MATERIALS AND METHODS Lytic development of Shiga toxin-converting bacteriophages was monitored after mitomycin C-provoked prophage induction under various conditions. Phage DNA replication efficiency was assessed by measurement of DNA amount in cells using quantitative polymerase chain reaction. RESULTS We demonstrated that the use of citrate delayed Shiga toxin-converting phage development after prophage induction. This effect was independent on efficiency of prophage induction and phage DNA replication. However, an excess of glucose reversed the effect of citrate. Amino acid starvation prevented the phage development in bacteria both able and unable to induce the stringent response. CONCLUSIONS Lytic development of Shiga toxin-converting bacteriophages can be inhibited by either the presence of citrate or amino acid starvation. We suggest that the inhibition caused by the latter condition may be due to a block in prophage induction or phage DNA replication or both. APPLICATIONS Our findings may facilitate development of procedures for treatment of STEC-infected patients.
Collapse
|
|
26
|
Maskow T, Kiesel B, Schubert T, Yong Z, Harms H, Yao J. Calorimetric real time monitoring of lambda prophage induction. J Virol Methods 2010; 168:126-32. [PMID: 20470826 DOI: 10.1016/j.jviromet.2010.05.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2009] [Revised: 04/28/2010] [Accepted: 05/05/2010] [Indexed: 11/29/2022]
Abstract
Calorimetry can be used for a noninvasive monitoring of metabolic and energy changes in bacterial cultures in real time. This potentially includes changes occurring during phage infection cycles. To demonstrate this, the growth of Escherichia coli K124 F(-) carrying the lambda prophage was monitored in a reaction calorimeter, while inducing the shift from lysogeny to lysis using methotrexate (MTX) as the inducer. Different phases of the phage infection were distinguishable calorimetrically. The calorimetric signals corresponded well to changes in growth stoichiometry and kinetics that were measured non-calorimetrically. The comparison of the calorimetric results with other measurements of activity revealed that the calorimetric method was superior since the calorimetric data mirrored the progress of infection in more detail. Contradictions between the calorimetric data and the appearance of infectious phages could result from inactivation of phage by MTX.
Collapse
Affiliation(s)
- Thomas Maskow
- UFZ, Helmholtz Centre for Environmental Research, Department of Environmental Microbiology, Permoserstr. Leipzig, Germany.
| | | | | | | | | | | |
Collapse
|
|
27
|
Loś JM, Loś M, Wegrzyn A, Wegrzyn G. Hydrogen peroxide-mediated induction of the Shiga toxin-converting lambdoid prophage ST2-8624 in Escherichia coli O157:H7. ACTA ACUST UNITED AC 2009; 58:322-9. [PMID: 20070366 DOI: 10.1111/j.1574-695x.2009.00644.x] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Shiga toxin-producing Escherichia coli (STEC) may cause bloody diarrhea and hemorrhagic colitis, with sometimes severe complications. Because genes coding for Shiga toxins are located on lambdoid prophages, effective toxin production occurs only after prophage induction. However, although agents that effectively induce prophage lambda (a paradigm of the family of lambdoid phages) under laboratory conditions, such as UV irradiation or DNA replication inhibitors, are well known, it is unlikely that such factors are present in human intestine infected with STEC. In this report, we demonstrate that induction of a Shiga toxin-converting prophage in its host (E. coli O157:H7) occurs not only in the presence of DNA-interfering antibiotics (mitomycin C and norfloxacin) but also under conditions of oxidative stress [following treatment with hydrogen peroxide (H(2)O(2))]. Under these conditions, we observed not only effective prophage induction but also expression of the reporter gene (replacing the original stx2 gene). In the light of previously published reports, indicating that oxidative stress conditions might occur during colonization of human intestine by enteric bacteria, and that neutrophil-produced H(2)O(2) can increase production of the Shiga toxin in a clinical isolate of STEC, these results suggest that oxidative stress may be one of the agents responsible for stimulating the pathogenicity determinants of STEC, leading to induction of Shiga toxin-converting prophages in these bacteria.
Collapse
Affiliation(s)
- Joanna M Loś
- Department of Molecular Biology, University of Gdańsk, Poland
| | | | | | | |
Collapse
|
|
28
|
Jofre J. Is the replication of somatic coliphages in water environments significant? J Appl Microbiol 2009; 106:1059-69. [DOI: 10.1111/j.1365-2672.2008.03957.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
|
29
|
Kitamoto D. [Naturally engineered glycolipid biosurfactants leading to distinctive self-assembling properties]. YAKUGAKU ZASSHI 2008; 128:695-706. [PMID: 18451615 DOI: 10.1248/yakushi.128.695] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Biosurfactants (BS) are functional amphiphilic compounds produced by a variety of microorganisms. They show unique properties (e.g. mild production conditions, lower toxicity, and environmental compatibility) compared to chemically synthesized counterparts. The numerous advantages of BS have prompted applications not only in the food, cosmetic, and pharmaceutical industries but in energy and environmental technologies as well. Mannosylerythritol lipids (MELs) are one of the most promising BS known, and are produced at yields of over 100 g/l from vegetable oils by yeast strains belonging to the genus Pseudozyma. MELs exhibit excellent surface-active and self-assembling properties leading to the formation of different lyotropic liquid crystals such as sponge (L(3)), bicontinuous cubic (V(2)) and lamella (L(alpha)) phases. They also show versatile biochemical actions, including antitumor and differentiation-inducing activities against human leukemia cells, rat pheochromocytoma cells and mouse melanoma cells. MELs also display high binding affinity toward different immunoglobulins and lectins, indicating great potentials as new affinity ligands for the glycoproteins. More significantly, the cationic liposomes bearing MELs increase dramatically the efficiency of gene transfection into mammalian cells via membrane fusion processes. The yeast BS should thus be novel nanobiomaterials, and broaden their applications in various advanced technologies.
Collapse
Affiliation(s)
- Dai Kitamoto
- Research Institute for Innovation in Sustainable Chemistry, National Institute of Advanced Science and Technology (AIST), Tsukuba City, Japan.
| |
Collapse
|
|
30
|
Thouand G, Vachon P, Liu S, Dayre M, Griffiths MW. Optimization and validation of a simple method using P22::luxAB bacteriophage for rapid detection of Salmonella enterica serotypes A, B, and D in poultry samples. J Food Prot 2008; 71:380-5. [PMID: 18326191 DOI: 10.4315/0362-028x-71.2.380] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A simple method was developed for the fast and inexpensive detection of Salmonella Typhimurium using a recombinant P22::luxAB phage. All the steps from phage production to detection were considered. A strain of Salmonella Typhimurium harboring the prophage P22::luxAB was grown in batch culture to produce spontaneously the recombinant bacteriophage. Batch production to stationary phase was better for propagation of the phage and led to a total population of 4.3 x 10(9) (+/-4.3 x 10(9)) PFU/ml of P22, including only 1.4 x 10(6) (+/-1 x 10(6)) PFU/ml harboring the luxAB genes. After preenrichment, a simple four-step bioassay was tested and optimized for several parameters. The detection limit of the luminometer was only 5 x 10(2) (+/-1.75 x 10(2)) CFU Salmonella Typhimurium per ml, but increased to 1.5 x 10(4) (+/-1.17 x 10(4)) CFU Salmonella Typhimurium per ml when the cells were in a complex matrix. The detection limit after the preenrichment was 6.5 x 10(3) (+/-1.5 x 10(3)) CFU Salmonella Typhimurium per ml, but the detection limit after the preenrichment also increased markedly to 1.65 x 10(5) (+/-0.15 x 10(5)) CFU Salmonella Typhimurium per ml when Salmonella Typhimurium was in a complex matrix. Finally, the bioassay was applied to the detection of Salmonella Typhimurium LT2 in 14 different feed and environmental samples (including duck feed, litters, and feces) spiked either before or after the preenrichment process. It was possible to detect Salmonella Typhimurium LT2 in all samples within 16 h.
Collapse
Affiliation(s)
- G Thouand
- University Nantes, UMR CNRS 6144 GEPEA ERT CBAC, Campus de la Courtaisière-IUT, Département Génie Biologique, 18 Bd Gaston Defferre, 85035 La Roche-sur-Yon cedex, France.
| | | | | | | | | |
Collapse
|
|
31
|
Muniesa M, Jofre J. The contribution of induction of temperate phages to the numbers of free somatic coliphages in waters is not significant. FEMS Microbiol Lett 2007; 270:272-6. [PMID: 17343678 DOI: 10.1111/j.1574-6968.2007.00676.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Somatic coliphages have been proposed as indicators of water quality. But several factors have been considered a drawback for their use as indicators. We evaluated the contribution of temperate phages to the numbers of somatic coliphages detected in water by ISO (International Standards Organization) standardised methods. Prophage induction from naturally occurring bacteria was assayed with mitomycin C, ciprofloxacin and UV irradiation. Results indicate that the presence of prophages will not influence the determinations of somatic coliphages in water.
Collapse
Affiliation(s)
- Maite Muniesa
- Department of Microbiology, Faculty of Biology, University of Barcelona, Barcelona, Spain
| | | |
Collapse
|
|
32
|
Łoś M, Golec P, Łoś JM, Weglewska-Jurkiewicz A, Czyz A, Wegrzyn A, Wegrzyn G, Neubauer P. Effective inhibition of lytic development of bacteriophages lambda, P1 and T4 by starvation of their host, Escherichia coli. BMC Biotechnol 2007; 7:13. [PMID: 17324284 PMCID: PMC1820593 DOI: 10.1186/1472-6750-7-13] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2006] [Accepted: 02/26/2007] [Indexed: 11/26/2022] Open
Abstract
Background Bacteriophage infections of bacterial cultures cause serious problems in genetic engineering and biotechnology. They are dangerous not only because of direct effects on the currently infected cultures, i.e. their devastation, but also due to a high probability of spreading the phage progeny throughout a whole laboratory or plant, which causes a real danger for further cultivations. Therefore, a simple method for quick inhibition of phage development after detection of bacterial culture infection should be very useful. Results Here, we demonstrate that depletion of a carbon source from the culture medium, which provokes starvation of bacterial cells, results in rapid inhibition of lytic development of three Escherichia coli phages, λ, P1 and T4. Since the effect was similar for three different phages, it seems that it may be a general phenomenon. Moreover, similar effects were observed in flask cultures and in chemostats. Conclusion Bacteriophage lytic development can be inhibited efficiently by carbon source limitation in bacterial cultures. Thus, if bacteriophage contamination is detected, starvation procedures may be recommended to alleviate deleterious effects of phage infection on the culture. We believe that this strategy, in combination with the use of automated and sensitive bacteriophage biosensors, may be employed in the fermentation laboratory practice to control phage outbreaks in bioprocesses more effectively.
Collapse
Affiliation(s)
- Marcin Łoś
- Department of Molecular Biology, University of Gdańsk, Kładki 24, 80-822 Gdańsk, Poland.
| | | | | | | | | | | | | | | |
Collapse
|
|
33
|
Łoś M, Łoś JM, Blohm L, Spillner E, Grunwald T, Albers J, Hintsche R, Wegrzyn G. Rapid detection of viruses using electrical biochips and anti-virion sera. Lett Appl Microbiol 2005; 40:479-85. [PMID: 15892746 DOI: 10.1111/j.1472-765x.2005.01706.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIMS Rapid detection and quantification of viruses is crucial in clinical practice, veterinary medicine, agriculture, basic research as well as in biotechnological factories. However, although various techniques were described and are currently used, development of more rapid, more sensitive and quantitative methods seems to be still important. METHODS AND RESULTS Here we describe a method for rapid detection of viruses (using bacteriophages as model viruses), based on electrical biochip array technology with the use of antibodies against capsid proteins. CONCLUSIONS Using the procedure developed in this work, we were able to detect 2 x 10(4) virions on the chip. The whole assay procedure takes c. 50 min and the assay is quantitative. SIGNIFICANCE AND IMPACT OF THE STUDY This procedure may be useful in various approaches, including detection of bacteriophage contamination in bioreactors and possibly detection of toxin gene-bearing phages or other viruses in food samples.
Collapse
Affiliation(s)
- M Łoś
- Department of Molecular Biology, University of Gdańsk, Gdańsk, Poland
| | | | | | | | | | | | | | | |
Collapse
|
|
34
|
Wegrzyn G, Wegrzyn A. Genetic switches during bacteriophage lambda development. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 2005; 79:1-48. [PMID: 16096026 DOI: 10.1016/s0079-6603(04)79001-7] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Affiliation(s)
- Grzegorz Wegrzyn
- Department of Molecular Biology, University of Gdańsk, 80-822 Gdańsk, Poland
| | | |
Collapse
|
|
35
|
Gabig-Ciminska M, Los M, Holmgren A, Albers J, Czyz A, Hintsche R, Wegrzyn G, Enfors SO. Detection of bacteriophage infection and prophage induction in bacterial cultures by means of electric DNA chips. Anal Biochem 2004; 324:84-91. [PMID: 14654049 DOI: 10.1016/j.ab.2003.09.020] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Infections of bacterial cultures by bacteriophages are common and serious problems in many biotechnological laboratories and factories. A method for specific, quantitative, and quick detection of phage contamination, based on the use of electric DNA chip is described here. Different phages of Escherichia coli and Bacillus subtilis were analyzed. Phage DNA was isolated from bacterial culture samples and detected by combination of bead-based sandwich hybridization with enzyme-labeled probes and detection of the enzymatic product using silicon chips. The assay resulted in specific signals from all four tested phages without significant background. Although high sensitivity was achieved in 4h assay time, a useful level of sensitivity (10(7)-10(8) phages) is achievable within 25 min. A multiplex DNA chip technique involving a mixture of probes allows for detection of various types of phages in one sample. These analyses confirmed the specificity of the assay.
Collapse
Affiliation(s)
- Magdalena Gabig-Ciminska
- Department of Biotechnology, Royal Institute of Technology (KTH), Roslagstullsbacken 21, S-10691 Stockholm, Sweden.
| | | | | | | | | | | | | | | |
Collapse
|
|
36
|
Lunde M, Blatny JM, Lillehaug D, Aastveit AH, Nes IF. Use of real-time quantitative PCR for the analysis of phiLC3 prophage stability in lactococci. Appl Environ Microbiol 2003; 69:41-8. [PMID: 12513975 PMCID: PMC152469 DOI: 10.1128/aem.69.1.41-48.2003] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacteriophages are a common and constant threat to proper milk fermentation. It has become evident that lysogeny is widespread in lactic acid bacteria, and in this work the temperate lactococcal bacteriophage phi LC3 was used as a model to study prophage stability in lactococci. The stability was analyzed in six phi LC3 lysogenic Lactococcus lactis subsp. cremoris host strains when they were growing at 15 and 30 degrees C. In order to perform these analyses, a real-time PCR assay was developed. The stability of the phi LC3 prophage was found to vary with the growth phase of its host L. lactis IMN-C1814, in which the induction rate increased during the exponential growth phase and reached a maximum level when the strain was entering the stationary phase. The maximum spontaneous induction frequency of the phi LC3 prophage varied between 0.32 and 9.1% (28-fold) in the six lysogenic strains. No correlation was observed between growth rates of the host cells and the spontaneous prophage induction frequencies. Furthermore, the level of extrachromosomal phage DNA after induction of the prophage varied between the strains (1.9 to 390%), and the estimated burst sizes varied up to eightfold. These results show that the host cells have a significant impact on the lytic and lysogenic life styles of temperate bacteriophages. The present study shows the power of the real-time PCR technique in the analysis of temperate phage biology and will be useful in work to reveal the impact of temperate phages and lysogenic bacteria in various ecological fields.
Collapse
Affiliation(s)
- Merete Lunde
- Laboratory of Microbial Gene Technology, Department of Chemistry and Biotechnology, Agricultural University of Norway, N-1432 Aas, Norway.
| | | | | | | | | |
Collapse
|