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Sada TS, Tessema TS. Isolation and characterization of lytic bacteriophages from various sources in Addis Ababa against antimicrobial-resistant diarrheagenic Escherichia coli strains and evaluation of their therapeutic potential. BMC Infect Dis 2024; 24:310. [PMID: 38486152 PMCID: PMC10938718 DOI: 10.1186/s12879-024-09152-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Accepted: 02/19/2024] [Indexed: 03/18/2024] Open
Abstract
BACKGROUND Escherichia coli is a common fecal coliform, facultative aerobic, gram-negative bacterium. Pathogenic strains of such microbes have evolved to cause diarrhea, urinary tract infections, and septicemias. The emergence of antibiotic resistance urged the identification of an alternative strategy. The use of lytic bacteriophages against the control of pathogenic E. coli in clinics and different environmental setups (waste and drink water management) has become an alternative therapy to antibiotic therapy. Thus, this study aimed to isolate and characterize lytic bacteriophage from various sources in Addis Ababa, tested them against antimicrobial-resistant diarrheagenic E. coli strains and evaluated their therapeutic potential under in vitro conditions. METHODS A total of 14 samples were processed against six different diarrheagenic E. coli strains. The conventional culture and plaque analysis agar overlay method was used to recover lytic bacteriophage isolates. The phage isolates were characterized to determine their lytic effect, growth characteristics, host range activity, and stability under different temperature and pH conditions. Phage isolates were identified by scanning electron microscope (SEM), and molecular techniques (PCR). RESULTS In total, 17 phages were recovered from 84 tested plates. Of the 17 phage isolates, 11 (65%) were Myoviridae-like phages, and 6 (35%) phage isolates were Podoviridae and Siphoviridae by morphology and PCR identification. Based on the host range test, growth characteristics, and stability test 7 potent phages were selected. These phages demonstrated better growth characteristics, including short latent periods, highest burst sizes, and wider host ranges, as well as thermal stability and the ability to survive in a wide range of pH levels. CONCLUSIONS The promising effect of the phages isolated in this study against AMR pathogenic E. coli has raised the possibility of their use in the future treatment of E. coli infections.
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Affiliation(s)
- Tamirat Salile Sada
- Institute of Biotechnology, Addis Ababa University, P.O.Box 1176, Addis Ababa, Ethiopia.
- Department of Biotechnology, Woldia University, P.O. Box 400, Woldia, Ethiopia.
| | - Tesfaye Sisay Tessema
- Institute of Biotechnology, Addis Ababa University, P.O.Box 1176, Addis Ababa, Ethiopia
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2
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Chaudhary V, Kajla P, Lather D, Chaudhary N, Dangi P, Singh P, Pandiselvam R. Bacteriophages: a potential game changer in food processing industry. Crit Rev Biotechnol 2024:1-25. [PMID: 38228500 DOI: 10.1080/07388551.2023.2299768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Accepted: 10/03/2023] [Indexed: 01/18/2024]
Abstract
In the food industry, despite the widespread use of interventions such as preservatives and thermal and non-thermal processing technologies to improve food safety, incidences of foodborne disease continue to happen worldwide, prompting the search for alternative strategies. Bacteriophages, commonly known as phages, have emerged as a promising alternative for controlling pathogenic bacteria in food. This review emphasizes the potential applications of phages in biological sciences, food processing, and preservation, with a particular focus on their role as biocontrol agents for improving food quality and preservation. By shedding light on recent developments and future possibilities, this review highlights the significance of phages in the food industry. Additionally, it addresses crucial aspects such as regulatory status and safety concerns surrounding the use of bacteriophages. The inclusion of up-to-date literature further underscores the relevance of phage-based strategies in reducing foodborne pathogenic bacteria's presence in both food and the production environment. As we look ahead, new phage products are likely to be targeted against emerging foodborne pathogens. This will further advance the efficacy of approaches that are based on phages in maintaining the safety and security of food.
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Affiliation(s)
- Vandana Chaudhary
- Department of Dairy Technology, College of Dairy Science and Technology, Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar, Haryana, India
| | - Priyanka Kajla
- Department of Food Technology, Guru Jambheshwar University of Science and Technology, Hisar, Haryana, India
| | - Deepika Lather
- Department of Veterinary Pathology, Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar, Haryana, India
| | - Nisha Chaudhary
- Department of Food Science and Technology, College of Agriculture, Agriculture University, Jodhpur, Rajasthan, India
| | - Priya Dangi
- Department of Food and Nutrition and Food Technology, Institute of Home Economics, University of Delhi, New Delhi, India
| | - Punit Singh
- Department of Mechanical Engineering, Institute of Engineering and Technology, GLA University Mathura, Mathura, Uttar Pradesh, India
| | - Ravi Pandiselvam
- Physiology, Biochemistry and Post-Harvest Technology Division, ICAR -Central Plantation Crops Research Institute, Kasaragod, Kerala, India
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3
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Phage Resistance Evolution Induces the Sensitivity of Specific Antibiotics in Pseudomonas aeruginosa PAO1. Microbiol Spectr 2022; 10:e0135622. [PMID: 35972274 PMCID: PMC9603957 DOI: 10.1128/spectrum.01356-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Bacteria frequently encounter selection by both phages and antibiotics. However, our knowledge on the evolutionary interactions between phages and antibiotics are still limited. Here, we characterized a phage-resistant Pseudomonas aeruginosa variant PAO1-R1 that shows increased sensitivity to gentamicin and polymyxin B. Using whole genome sequencing, significant genome differences were observed between the reference P. aeruginosa PAO1 and PAO1-R1. Compared to PAO1, 64 gene-encoding proteins with nonsynonymous single nucleotide polymorphisms (SNPs) and 31 genes with insertion/deletion (indel) mutations were found in PAO1-R1. We observed a significant reduction in phage adsorption rate for both phage vB_Pae_QDWS and vB_Pae_W3 against PAO1-R1 and proposed that disruption of phage adsorption is likely the main cause for evolving resistance. Because the majority of spontaneous mutations are closely related to membrane components, alterations in the cell envelope may explain the antibiotic-sensitive phenotype of PAO1-R1. Collectively, we demonstrate that the evolution of phage resistance comes with fitness defects resulting in antibiotic sensitization. Our finding provides new insights into the evolutionary interactions between resistance to the phage and sensitivity to antibiotics, which may have implications for the future clinical use of steering in phage therapies. IMPORTANCE Bacteria frequently encounter the selection pressure from both antibiotics and lytic phages. Little is known about the evolutionary interactions between antibiotics and phages. Our study provides new insights into the trade-off mechanism between resistance to the phage and sensitivity to antibiotics. This evolutionary trade-off is not dependent on the outer membrane proteins (OMPs) of the multidrug efflux pumps. The disruption of phage adsorption that induced phage resistance and the changes in structure or composition of membranes are presumably one of the major causes for antibiotic sensitivity. Our finding may fill some gaps in the field of phage-host interplay and have implications for the future clinical use of steering in phage therapies.
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4
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Zhu H, Guo S, Zhao J, Arbab Sakandar H, Lv R, Wen Q, Chen X. Whole Genome Sequence Analysis of Lactiplantibacillus plantarum Bacteriophage P2. Pol J Microbiol 2022; 71:421-428. [PMID: 36185020 PMCID: PMC9608156 DOI: 10.33073/pjm-2022-037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 07/22/2022] [Indexed: 11/24/2022] Open
Abstract
Phage P2 was isolated from failed fermentation broth carried out by Lactiplantibacillus plantarum IMAU10120. A previous study in our laboratory showed that this phage belonged to the Siphoviridae family. In this study, this phage’s genomic characteristics were analyzed using whole-genome sequencing. It was revealed that phage P2 was 77.9 kb in length and had 39.28% G + C content. Its genome included 96 coding sequences (CDS) and two tRNA genes involved in the function of the structure, DNA replication, packaging, and regulation. Phage P2 had higher host specificity; many tested strains were not infected. Cell wall adsorption experiments showed that the adsorption receptor component of phage P2 might be a part of the cell wall peptidoglycan. This research might enrich the knowledge about genomic information of lactobacillus phages and provide some primary data to establish phage control measures.
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Affiliation(s)
- Hanfang Zhu
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot, P.R.China,Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs, Inner Mongolia Agricultural University, Hohhot, P.R.China,Collaborative Innovative Center of Ministry of Education for Lactic Acid Bacteria and Fermented Dairy Products, Inner Mongolia Agricultural University, Hohhot, P.R.China
| | - She Guo
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot, P.R.China,Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs, Inner Mongolia Agricultural University, Hohhot, P.R.China,Collaborative Innovative Center of Ministry of Education for Lactic Acid Bacteria and Fermented Dairy Products, Inner Mongolia Agricultural University, Hohhot, P.R.China
| | - Jie Zhao
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot, P.R.China,Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs, Inner Mongolia Agricultural University, Hohhot, P.R.China,Collaborative Innovative Center of Ministry of Education for Lactic Acid Bacteria and Fermented Dairy Products, Inner Mongolia Agricultural University, Hohhot, P.R.China
| | - Hafiz Arbab Sakandar
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot, P.R.China,Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs, Inner Mongolia Agricultural University, Hohhot, P.R.China,Collaborative Innovative Center of Ministry of Education for Lactic Acid Bacteria and Fermented Dairy Products, Inner Mongolia Agricultural University, Hohhot, P.R.China
| | - Ruirui Lv
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot, P.R.China,Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs, Inner Mongolia Agricultural University, Hohhot, P.R.China,Collaborative Innovative Center of Ministry of Education for Lactic Acid Bacteria and Fermented Dairy Products, Inner Mongolia Agricultural University, Hohhot, P.R.China
| | - Qiannan Wen
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot, P.R.China,Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs, Inner Mongolia Agricultural University, Hohhot, P.R.China,Collaborative Innovative Center of Ministry of Education for Lactic Acid Bacteria and Fermented Dairy Products, Inner Mongolia Agricultural University, Hohhot, P.R.China
| | - Xia Chen
- Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot, P.R.China,Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs, Inner Mongolia Agricultural University, Hohhot, P.R.China,Collaborative Innovative Center of Ministry of Education for Lactic Acid Bacteria and Fermented Dairy Products, Inner Mongolia Agricultural University, Hohhot, P.R.China, X. Chen, Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot, China # Hanfang Zhu and She Guo have contributed equally to this study.
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5
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Isolation, characterization, and application of bacteriophages to reduce and inhibit Listeria monocytogenes in celery and enoki mushroom. Food Control 2022. [DOI: 10.1016/j.foodcont.2022.108826] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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6
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Isolation and characterization of Escherichia coli O157: H7 novel bacteriophage for controlling this food-borne pathogen. Virus Res 2022; 315:198754. [PMID: 35346752 DOI: 10.1016/j.virusres.2022.198754] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 03/18/2022] [Accepted: 03/22/2022] [Indexed: 11/20/2022]
Abstract
Escherichia coli O157: H7 is known as a high-risk food-born pathogen, and its removal is vital for maintaining food safety. The increasing trend of food-borne diseases caused by this bacterium and other pathogens indicates the low efficiency of the methods to remove pathogens from foodstuffs. One of the new and effective methods is to use of a bio-control agent called bacteriophage, which has shown good function in eliminating and reducing pathogens. In this study, a novel bacteriophage was isolated and identified from the slaughterhouse wastewater to control E. coli O157: H7. This bacteriophage belonged to the Myoviridae family. Two bacterial genera including E. coli and Salmonella, were allocated to determine the bacteriophage host range; the result showed that the anti- Salmonella effect of phage was low. The phage was stable at high temperature (80°C) and caused an acceptable reduction in the E. coli O157: H7 (4.18 log CFU / mL for 10 hours). The isolated bacteriophage was corroborated to be completely safe based on the whole genome sequencing and lack of any virulence factor from the host bacteria. Considering the characteristics of this phage and its function in vitro, this bacteriophage may be used as an effective bio-control agent in foods with the possible E. coli O157: H7 -induced contamination.
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7
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Ma F, Ning Y, Wan Q, Zou L, Liu Y, Chen S, Li J, Zeng Z, Yang Y, Chen H, Zhou M, Liu S, Li C, Liu A. Bacteriophages LSA2308 and LSA2366 infecting drug-resistant Staphylococcus aureus: Isolation, characterization and potential application for milk safety. Lebensm Wiss Technol 2021. [DOI: 10.1016/j.lwt.2021.112298] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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8
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Li Y, Wu X, Chen H, Zhao Y, Shu M, Zhong C, Wu G. A bacteriophage JN02 infecting multidrug‐resistant Shiga toxin‐producing
Escherichia
coli
: isolation, characterisation and application as a biocontrol agent in foods. Int J Food Sci Technol 2021. [DOI: 10.1111/ijfs.15070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Ya‐Ke Li
- College of Food Science and Engineering Jiangxi Agricultural University Nanchang China
| | - Xin Wu
- Jiangxi Province Food Control Institute Nanchang China
| | - Hu Chen
- College of Food Science and Engineering Jiangxi Agricultural University Nanchang China
| | - Yuan‐Yang Zhao
- College of Food Science and Engineering Jiangxi Agricultural University Nanchang China
| | - Mei Shu
- College of Food Science and Engineering Jiangxi Agricultural University Nanchang China
| | - Chan Zhong
- College of Food Science and Engineering Jiangxi Agricultural University Nanchang China
| | - Guo‐Ping Wu
- College of Food Science and Engineering Jiangxi Agricultural University Nanchang China
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9
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López-Cuevas O, Medrano-Félix JA, Castro-Del Campo N, Chaidez C. Bacteriophage applications for fresh produce food safety. INTERNATIONAL JOURNAL OF ENVIRONMENTAL HEALTH RESEARCH 2021; 31:687-702. [PMID: 31646886 DOI: 10.1080/09603123.2019.1680819] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 10/11/2019] [Indexed: 06/10/2023]
Abstract
Foodborne illnesses, mainly bacteria, are a major cause of morbidity and mortality worldwide. Pathogenic bacteria are involved in almost every step within the fresh produce chain compromising the companies' food safety programs and generating an ascending number of foodborne outbreaks in various regions of the world. Recently, bacteriophages return to the status of biocontrol agents. These bacteria-killing viruses are able to reduce or eliminate pathogenic bacterial load from raw and ready to eat foods. Phages are efficient, strain specific, easy to isolate and manipulate, and for that reasons, they have been used in pre and post harvest processes alone or mixed with antimicrobial agents for biocontrolling pathogenic bacteria. In this review, we focused on the feasibility of using lytic bacteriophage on fresh fruits and vegetables industry, considering challenges and perspectives mainly at industrial production level (packinghouses, supermarkets), where high volume of phage preparations and consequently high costs may be required.
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Affiliation(s)
- O López-Cuevas
- Laboratorio Nacional para la Investigación en Inocuidad Alimentari (LANIIA), Centro de Investigación en Alimentación y Desarrollo, A.C Culiacán, México
| | - J A Medrano-Félix
- CONACYT-Centro de Investigación en Alimentación y Desarrollo, A.C Culiacán, México
| | - N Castro-Del Campo
- Laboratorio Nacional para la Investigación en Inocuidad Alimentari (LANIIA), Centro de Investigación en Alimentación y Desarrollo, A.C Culiacán, México
| | - C Chaidez
- Laboratorio Nacional para la Investigación en Inocuidad Alimentari (LANIIA), Centro de Investigación en Alimentación y Desarrollo, A.C Culiacán, México
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Mutant and Recombinant Phages Selected from In Vitro Coevolution Conditions Overcome Phage-Resistant Listeria monocytogenes. Appl Environ Microbiol 2020; 86:AEM.02138-20. [PMID: 32887717 DOI: 10.1128/aem.02138-20] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 08/31/2020] [Indexed: 12/17/2022] Open
Abstract
Bacteriophages (phages) are currently available for use by the food industry to control the foodborne pathogen Listeria monocytogenes Although phage biocontrols are effective under specific conditions, their use can select for phage-resistant bacteria that repopulate phage-treated environments. Here, we performed short-term coevolution experiments to investigate the impact of single phages and a two-phage cocktail on the regrowth of phage-resistant L. monocytogenes and the adaptation of the phages to overcome this resistance. We used whole-genome sequencing to identify mutations in the target host that confer phage resistance and in the phages that alter host range. We found that infections with Listeria phages LP-048, LP-125, or a combination of both select for different populations of phage-resistant L. monocytogenes bacteria with different regrowth times. Phages isolated from the end of the coevolution experiments were found to have gained the ability to infect phage-resistant mutants of L. monocytogenes and L. monocytogenes strains previously found to be broadly resistant to phage infection. Phages isolated from coinfected cultures were identified as recombinants of LP-048 and LP-125. Interestingly, recombination events occurred twice independently in a locus encoding two proteins putatively involved in DNA binding. We show that short-term coevolution of phages and their hosts can be utilized to obtain mutant and recombinant phages with adapted host ranges. These laboratory-evolved phages may be useful for limiting the emergence of phage resistance and for targeting strains that show general resistance to wild-type (WT) phages.IMPORTANCE Listeria monocytogenes is a life-threatening bacterial foodborne pathogen that can persist in food processing facilities for years. Phages can be used to control L. monocytogenes in food production, but phage-resistant bacterial subpopulations can regrow in phage-treated environments. Coevolution experiments were conducted on a Listeria phage-host system to provide insight into the genetic variation that emerges in both the phage and bacterial host under reciprocal selective pressure. As expected, mutations were identified in both phage and host, but additionally, recombination events were shown to have repeatedly occurred between closely related phages that coinfected L. monocytogenes This study demonstrates that in vitro evolution of phages can be utilized to expand the host range and improve the long-term efficacy of phage-based control of L. monocytogenes This approach may also be applied to other phage-host systems for applications in biocontrol, detection, and phage therapy.
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11
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Zhou C, Zhu M, Wang Y, Yang Z, Ye M, Wu L, Bao H, Pang M, Zhou Y, Wang R, Sun L, Wang H, Zheng C, Zhang H. Broad host range phage vB-LmoM-SH3-3 reduces the risk of Listeria contamination in two types of ready-to-eat food. Food Control 2020. [DOI: 10.1016/j.foodcont.2019.106830] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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12
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Liu A, Liu Y, Peng L, Cai X, Shen L, Duan M, Ning Y, Liu S, Li C, Liu Y, Chen H, Wu W, Wang X, Hu B, Li C. Characterization of the narrow-spectrum bacteriophage LSE7621 towards Salmonella Enteritidis and its biocontrol potential on lettuce and tofu. Lebensm Wiss Technol 2020. [DOI: 10.1016/j.lwt.2019.108791] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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13
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Montso PK, Mlambo V, Ateba CN. Characterization of Lytic Bacteriophages Infecting Multidrug-Resistant Shiga Toxigenic Atypical Escherichia coli O177 Strains Isolated From Cattle Feces. Front Public Health 2019; 7:355. [PMID: 32039126 PMCID: PMC6988782 DOI: 10.3389/fpubh.2019.00355] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Accepted: 11/07/2019] [Indexed: 11/13/2022] Open
Abstract
The increasing incidence of antibiotic resistance and emergence of virulent bacterial pathogens, coupled with a lack of new effective antibiotics, has reignited interest in the use of lytic bacteriophage therapy. The aim of this study was to characterize lytic Escherichia coli O177-specific bacteriophages isolated from cattle feces to determine their potential application as biocontrol agents. A total of 31 lytic E. coli O177-specific bacteriophages were isolated. A large proportion (71%) of these phage isolates produced large plaques while 29% produced small plaques on 0.3% soft agar. Based on different plaque morphologies and clarity and size of plaques, eight phages were selected for further analyses. Spot test and efficiency of plating (EOP) analyses were performed to determine the host range for selected phages. Phage morphotype and growth were analyzed using transmission electron microscopy and the one-step growth curve method. Phages were also assessed for thermal and pH stability. The spot test revealed that all selected phages were capable of infecting different environmental E. coli strains. However, none of the phages infected American Type Culture Collection (ATCC) and environmental Salmonella strains. Furthermore, EOP analysis (range: 0.1-1.0) showed that phages were capable of infecting a wide range of E. coli isolates. Selected phage isolates had a similar morphotype (an icosahedral head and a contractile tail) and were classified under the order Caudovirales, Myoviridae family. The icosahedral heads ranged from 81.2 to 110.77 nm, while the contractile tails ranged from 115.55 to 132.57 nm in size. The phages were found to be still active after 60 min of incubation at 37 and 40°C. Incremental levels of pH induced a quadratic response on stability of all phages. The pH optima for all eight phages ranged between 7.6 and 8.0, while at pH 3.0 all phages were inactive. Phage latent period ranged between 15 and 25 min while burst size ranged from 91 to 522 virion particles [plaque-forming unit (PFU)] per infected cell. These results demonstrate that lytic E. coli O177-specific bacteriophages isolated from cattle feces are highly stable and have the capacity to infect different E. coli strains, traits that make them potential biocontrol agents.
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Affiliation(s)
- Peter Kotsoana Montso
- Bacteriophage Therapy and Phage Bio-Control Laboratory, Department of Microbiology, Faculty of Natural and Agricultural Sciences, North-West University, Mmabatho, South Africa
- Food Security and Safety Niche Area, North-West University, Mmabatho, South Africa
| | - Victor Mlambo
- Faculty of Agriculture and Natural Sciences, School of Agricultural Sciences, University of Mpumalanga, Mbombela, South Africa
| | - Collins Njie Ateba
- Bacteriophage Therapy and Phage Bio-Control Laboratory, Department of Microbiology, Faculty of Natural and Agricultural Sciences, North-West University, Mmabatho, South Africa
- Food Security and Safety Niche Area, North-West University, Mmabatho, South Africa
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14
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Complete Genome Sequences of Two Listeria Phages of the Genus Pecentumvirus. Microbiol Resour Announc 2019; 8:8/46/e01229-19. [PMID: 31727716 PMCID: PMC6856282 DOI: 10.1128/mra.01229-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacteriophages isolated from environmental sources can be used as a biocontrol against the foodborne pathogen Listeria monocytogenes Here, we present the complete genomes of LP-039 and LP-066, two Pecentumvirus bacteriophages that infect L. monocytogenes The genome sizes of LP-039 and LP-066 are 136.2 kb and 139.0 kb, respectively.
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