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1
Samir, Safia. "Bacteriophages as Therapeutic Agents: Alternatives to Antibiotics." Recent Patents on Biotechnology 15, no. 1 (May 7, 2021): 25–33. http://dx.doi.org/10.2174/1872208315666210121094311.
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: Bacteriophages are bacterio-specific viruses that constitute the main portion of the environment. Bacteriophages inject their genome into the targeted bacterial cells and some of them can disrupt the metabolism of bacteria and cause bacterial cell disintegration. The application of bacteriophages to kill bacteria is known as bacteriophage therapy. Since bacteriophages target bacteria and are strain-specific, every bacteriophage/bacterial host pair is unique. They are believed to cause no harm to humans. An additional advantage of the strain-specific nature of bacteriophages is that they do not disrupt the beneficial natural flora in the body. Bacteriophage therapy in the West is not a recognized medicine at this time, and no products are registered. Some clinicians are turning to bacteriophage therapy for the treatment of antibiotic-resistant infections. Lack of adverse effects makes bacteriophage therapy ideal for use. Funding research, media attention, and the increased publication of articles helped in a widespread understanding of its therapeutic potential. The first prerequisite for the use of bacteriophage therapy is simply the availability of bacteriophages for treatment, which is often complicated at this stage of bacteriophage production. This includes providing access to all biologically active bacteriophages against the bacterial isolate of the patient and meeting regulatory criteria of purity, traceability, and characterization. A monophage preparation, which is a single bacteriophage, or a phage cocktail, which consists of a number of combined bacteriophages against one or more bacterial species may be used. Accordingly, the antibiotic resistance crisis brought back bacteriophage therapy as a potential complementary or alternative treatment. Bacteriophages are promising cheap antibacterials.
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Putra, Ramendra Dirgantara, and Diana Lyrawati. "Interactions between Bacteriophages and Eukaryotic Cells." Scientifica 2020 (June 9, 2020): 1–8. http://dx.doi.org/10.1155/2020/3589316.
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As the name implies, bacteriophage is a bacterium-specific virus. It infects and kills the bacterial host. Bacteriophages have gained attention as alternative antimicrobial entities in the science community in the western world since the alarming rise of antibiotic resistance among microbes. Although generally considered as prokaryote-specific viruses, recent studies indicate that bacteriophages can interact with eukaryotic organisms, including humans. In the current review, these interactions are divided into two categories, i.e., indirect and direct interactions, with the involvement of bacteriophages, bacteria, and eukaryotes. We discuss bacteriophage-related diseases, transcytosis of bacteriophages, bacteriophage interactions with cancer cells, collaboration of bacteriophages and eukaryotes against bacterial infections, and horizontal gene transfer between bacteriophages and eukaryotes. Such interactions are crucial for understanding and developing bacteriophages as the therapeutic agents and pharmaceutical delivery systems. With the advancement and combination of in silico, in vitro, and in vivo approaches and clinical trials, bacteriophages definitely serve as useful repertoire for biologic target-based drug development to manage many complex diseases in the future.
3
Manrique, Pilar, Benjamin Bolduc, Seth T. Walk, John van der Oost, Willem M. de Vos, and Mark J. Young. "Healthy human gut phageome." Proceedings of the National Academy of Sciences 113, no. 37 (August 29, 2016): 10400–10405. http://dx.doi.org/10.1073/pnas.1601060113.
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The role of bacteriophages in influencing the structure and function of the healthy human gut microbiome is unknown. With few exceptions, previous studies have found a high level of heterogeneity in bacteriophages from healthy individuals. To better estimate and identify the shared phageome of humans, we analyzed a deep DNA sequence dataset of active bacteriophages and available metagenomic datasets of the gut bacteriophage community from healthy individuals. We found 23 shared bacteriophages in more than one-half of 64 healthy individuals from around the world. These shared bacteriophages were found in a significantly smaller percentage of individuals with gastrointestinal/irritable bowel disease. A network analysis identified 44 bacteriophage groups of which 9 (20%) were shared in more than one-half of all 64 individuals. These results provide strong evidence of a healthy gut phageome (HGP) in humans. The bacteriophage community in the human gut is a mixture of three classes: a set of core bacteriophages shared among more than one-half of all people, a common set of bacteriophages found in 20–50% of individuals, and a set of bacteriophages that are either rarely shared or unique to a person. We propose that the core and common bacteriophage communities are globally distributed and comprise the HGP, which plays an important role in maintaining gut microbiome structure/function and thereby contributes significantly to human health.
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Maura, Damien, Matthieu Galtier, Chantal Le Bouguénec, and Laurent Debarbieux. "Virulent Bacteriophages Can Target O104:H4 Enteroaggregative Escherichia coli in the Mouse Intestine." Antimicrobial Agents and Chemotherapy 56, no. 12 (September 24, 2012): 6235–42. http://dx.doi.org/10.1128/aac.00602-12.
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ABSTRACTIn vivobacteriophage targeting of enteroaggregativeEscherichia coli(EAEC) was assessed using a mouse intestinal model of colonization with the O104:H4 55989Str strain and a cocktail of three virulent bacteriophages. The colonization model was shown to mimic asymptomatic intestinal carriage found in humans. The addition of the cocktail to drinking water for 24 h strongly decreased ileal and weakly decreased fecal 55989Str concentrations in a dose-dependent manner. These decreases in ileal and fecal bacterial concentrations were only transient, since 55989Str concentrations returned to their original levels 3 days later. These transient decreases were independent of the mouse microbiota, as similar results were obtained with axenic mice. We studied the infectivity of each bacteriophage in the ileal and fecal environments and found that 55989Str bacteria in the mouse ileum were permissive to all three bacteriophages, whereas those in the feces were permissive to only one bacteriophage. Our results provide the first demonstration that bacterial permissivity to infection with virulent bacteriophages is not uniform throughout the gut; this highlights the need for a detailed characterization of the interactions between bacteria and bacteriophagesin vivofor the further development of phage therapy targeting intestinal pathogens found in the gut of asymptomatic human carriers.
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SAKMANOĞLU, Aslı, та Hasan Hüseyin HADİMLİ. "Typing of ΦSP–3 lytic Salmonella bacteriophages obtained from various fecal sources". TURKISH JOURNAL OF VETERINARY AND ANIMAL SCIENCES 44, № 5 (27 жовтня 2020): 1047–54. http://dx.doi.org/10.3906/vet-2005-105.
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Although several reports are available on both ΦSP–1 and ΦSP–3 lytic Salmonella bacteriophages obtained from poultry, further research is required to study the effectiveness of ΦSP–3 type on serovars isolated from other sources. In the present study, we aimed to isolate bacteriophages from 8 serovars previously obtained from 869 fecal samples (calf, dairy cow, buffalo, and camel), genotype the bacteriophages, and detect the cross-lytic activities of the bacteriophages on Salmonella enterica subsp. enterica serovar Kentucky, S.Anatum, and S.Muenchen. A total of 16 bacteriophages were detected as ΦSP–3 type via PCR. The Hunter-Gaston Discriminatory Index of SDS-PAGE was calculated to be 0.825. Determination of multiplicity of infection (MOI) values were different for each bacteriophage according to the cross-lytic activity assessment. The MOI of the most effective S. Kentucky bacteriophage was 79.11 μg/mL for 2.5×104 cells, whereas that of the most ineffective S.Muenchen bacteriophage was 1.142 μg/μL for 2.5×104 cells. In conclusion, it was assumed that owing to the high and cross-lytic activity of the S. Kentucky bacteriophage, it has a larger host range, which differs in the lytic activities of each bacteriophage, despite being the same serovar, and that calf feces is the most important source for obtaining Salmonella bacteriophages.
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Ariyanti, Tati. "The Use of Bacteriophage for Detection and Biocontrol of Foodborne Pathogen." Indonesian Bulletin of Animal and Veterinary Sciences 28, no. 1 (March 3, 2018): 33. http://dx.doi.org/10.14334/wartazoa.v28i1.1791.
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Bacteriophages are viruses that have ability to attack bacterial cells in specific receptors, infect, multiply in bacterial cells and eventually lyse bacterial cells. This unique bacteriophage character is highly beneficial because it is harmless to mammalian cells and does not interfere with natural microbes. Bacteriophages are easy to obtain because they are widespread in the environment such as soil, water, animal, and farm waste or food. This paper describes the potential use of bacteriophages to detect pathogen and foodborne pathogen biocontrol. Bacteriophages are very potential to control the growth of pathogenic bacteria both in food industry and environment. Bacteriophages act as antibiotics, detection tool for pathogenic bacteria in the food chain, food biopreservative from pathogen bacteria contamination, and foodborne disease prevention. Although research on bacteriophage in Indonesia has not been widely reported, research on bacteriophage utilization is being carried on.
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Moon, Choi, Jeong, Sohn, Han, and Oh. "Research Progress of M13 Bacteriophage-Based Biosensors." Nanomaterials 9, no. 10 (October 11, 2019): 1448. http://dx.doi.org/10.3390/nano9101448.
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Recently, new virus-based sensor systems that operate on M13 bacteriophage infrastructure have attracted considerable attention. These systems can detect a range of chemicals with excellent sensitivity and selectivity. Filaments consistent with M13 bacteriophages can be ordered by highly established forms of self-assembly. This allows M13 bacteriophages to build a homogeneous distribution and infiltrate the network structure of nanostructures under mild conditions. Phage display, involving the genetic engineering of M13 bacteriophages, is another strong feature of the M13 bacteriophage as a functional building block. The numerous genetic modification possibilities of M13 bacteriophages are clearly the key features, and far more applications are envisaged. This paper reviews the recent progress in the application of the M13 bacteriophage self-assembly structures through to sensor systems and discusses future M13 bacteriophage technology.
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TARAKANOV, R. I., A. N. IGNATOV, and F. S. DZHALILOV. "ISOLATION OF SPECIFIC BACTERIOPHAGES - PSEUDOMONAS SAVASTANOI PV. GLYCINEA - AND THEIR USE IN SOYBEAN BACTERIAL BLIGHT CONTROL." Izvestiâ Timirâzevskoj selʹskohozâjstvennoj akademii, no. 4 (2020): 43–53. http://dx.doi.org/10.26897/0021-342x-2020-4-43-53.
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Bacterial blight is one of most harmful diseases of legumes, reducing the profitability of soybean production in Russian Federation. Among a number of Pseudomonas isolates obtained from diseased seeds and plants of soybean, 4 strains were selected and confirmed as Pseudomonas savastanoipv. glycinea (Psg). Properties of the isolated bacteria were similar to type strain of Psg CFBP 2214 in plant virulence, LOPAT tests, and PCR analysis for coronafacate ligase gene, and partly – in the phage reaction profile. Four isolates of bacteriophages specific to Psg were obtained from soil samples taken from fields with soybean crops. Virulence testing for the bacteriophages showed that bacteriophage ϕG17 infected 4 of 5 tested Psg strains, and it was chosen for further experiments with bacterial blight control. The bacteriophague effect control conducted on soybent plants inoculated by Psg experiments confirmed that 2 treatments of plants by the bacteriophage significantly reduced the disease development. Biological effect of the bacteriophage application was 74.75%, which is very close to the pesticide Strekar in a concentration of 0.5%.
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Xu, Anqi. "Draft Of Bacteriophage Therapy Review." Highlights in Science, Engineering and Technology 74 (December 29, 2023): 1105–16. http://dx.doi.org/10.54097/hfwfxj54.
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Phage therapy, which uses bacterial viruses (bacteriophages) to treat bacterial infections. In recent years, the issue of antibiotic resistance in various bacteria has become prominent, and the effectiveness of antibiotic drugs has generally declined, which has re raised people's scrutiny of bacteriophage therapy. Traditionally, bacteriophage therapy relies on the use of natural bacteriophages to infect and dissolve bacteria at the site of infection. Current research on the use of bacteriophages and their lytic proteins to combat multidrug-resistant bacterial infections suggests that bacteriophage therapy may serve as a substitute or supplement to antibiotic therapy.
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Gorshenin, Aleksandr Vladimirovich. "Participation of microbiologists Z.V. Ermolyeva and L.M. Yakobson in a scientific discussion about the fate of the production of Soviet cholera bacteriophages in 1967." Samara Journal of Science 10, no. 4 (December 1, 2021): 201–7. http://dx.doi.org/10.17816/snv2021104211.
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Since the late 1920s in the USSR, along with many countries, there has been an interest in studying the phenomenon of bacteriophagy and its use in medicine. Bacteriophages are called bacterial viruses. Significant work on the study of bacteriophages and their use for medical purposes was carried out by Soviet microbiologists Zinaida Vissarionovna Ermolyeva and Lidiya Mikhailovna Yakobson. They paid especially great attention to the study of cholera bacteriophage, which during the Great Patriotic War helped prevent the cholera epidemic in frontline Stalingrad. In the 1940s due to the advent of the era of antibiotics with a wider range of applications, research interest in bacteriophages was waning. Nevertheless, in the prevention and treatment of a number of infectious diseases of bacterial origin, phage continued to be used in the following decades. In 1967, one of the countrys largest microbiologists sent an appeal to the Chief Sanitary Doctor of the USSR with a proposal to stop or reduce the production of cholera bacteriophage in the country. In this regard, a scientific discussion in which Z.V. Ermolyeva and L.M. Yakobson played an important role unfolded. Using the materials of the State Archive of the Russian Federation and the Russian State Archive of Economics, involving published scientific works on microbiology and medicine, an attempt is made to analyze this scientific discussion and establish its significance in the fate of the production of cholera bacteriophage in the USSR.
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Florent, Perrine, Henry-Michel Cauchie, Malte Herold, Stéphan Jacquet, and Leslie Ogorzaly. "Soil pH, Calcium Content and Bacteria as Major Factors Responsible for the Distribution of the Known Fraction of the DNA Bacteriophage Populations in Soils of Luxembourg." Microorganisms 10, no. 7 (July 19, 2022): 1458. http://dx.doi.org/10.3390/microorganisms10071458.
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Bacteriophages participate in soil life by influencing bacterial community structure and function, biogeochemical cycling and horizontal gene transfer. Despite their great abundance, diversity, and importance in microbial processes, they remain little explored in environmental studies. The influence of abiotic factors on the persistence of bacteriophages is now recognized; however, it has been mainly studied under experimental conditions. This study aimed to determine whether the abiotic factors well-known to influence bacteriophage persistence also control the natural distribution of the known DNA bacteriophage populations. To this end, soil from eight study sites including forests and grasslands located in the Attert River basin (Grand Duchy of Luxembourg) were sampled, covering different soil and land cover characteristics. Shotgun metagenomics, reference-based bioinformatics and statistical analyses allowed characterising the diversity of known DNA bacteriophage and bacterial communities. After combining soil properties with the identified DNA bacteriophage populations, our in-situ study highlighted the influence of pH and calcium cations on the diversity of the known fraction of the soil DNA bacteriophages. More interestingly, significant relationships were established between bacteriophage and bacterial populations. This study provides new insights into the importance of abiotic and biotic factors in the distribution of DNA bacteriophages and the natural ecology of terrestrial bacteriophages.
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Raees, Fahad, Azian Harun, Abdalla Ahmed, and Zakuan Zainy Deris. "Potential Usefulness of Bacteriophages for the Treatment of Multidrug-Resistant Acinetobacter Infection." Malaysian Journal of Medical Sciences 30, no. 5 (October 30, 2023): 7–22. http://dx.doi.org/10.21315/mjms2023.30.5.2.
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Bacteriophages were discovered in early 20th century. However, the interest in bacteriophage research was reduced with the discovery of antibiotics. With the increasing number of infections due to multidrug-resistant (MDR) organisms, the potential usefulness of bacteriophages as therapeutic agents has been re-evaluated. In this review, we found that more than 30 lytic bacteriophages that infect Acinetobacter species have been characterised. These are mainly members of Caudovirales, with genome sizes ranging from 31 kb to 234 kb and G+C contents ranging from 33.5% to 45.5%. The host range can be as low as < 10% of all tested Acinetobacter strains. Fourteen published murine trials indicated positive outcomes in bacteriophage-treated groups. Only two case reports were pertaining to the use of bacteriophages in the treatment of Acinetobacter infections in humans; in both cases, the infections were resolved with bacteriophage therapy. The use of bacteriophages has been associated with reduced Acinetobacter burden in the environment, as shown in two studies. The major limitation of bacteriophage therapy is its highly selective host strain. In conclusion, the potential usefulness of bacteriophage therapy for the treatment of MDR Acinetobacter species has been documented only in limited studies and more research is needed prior to its extensive use in clinical practice.
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Musin, Egor V., Aleksandr L. Kim, Alexey V. Dubrovskii, Elena V. Ariskina, Ekaterina B. Kudryashova, and Sergey A. Tikhonenko. "The Pathways to Create Containers for Bacteriophage Delivery." Polymers 14, no. 3 (February 4, 2022): 613. http://dx.doi.org/10.3390/polym14030613.
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Antimicrobial resistance is a global public health threat. One of the possible ways to solve this problem is phage therapy, but the instability of bacteriophages hinders the development of this approach. A bacteriophage delivery system that stabilizes the phage is one of the possible solutions to this problem. This study is dedicated to exploring methods to create encapsulated forms of bacteriophages for delivery. We studied the effect of proteolytic enzymes on the destruction of the polyelectrolyte microcapsule shell and revealed that protease from Streptomyces griseus was able to destroy the membrane of the microcapsule (dextran sulfate/polyarginine)3 ((DS/PArg)3). In addition, the protease decreased the activity of the bacteriophage in the second hour of incubation, and the phage lost activity after 16 h. It was found that a medium with pH 9.02 did not affect the survival of the bacteriophage or E. coli. The bacteriophages were encapsulated into polyelectrolyte microcapsules (DS/PArg)3. It was established that it is impossible to use microcapsules as a means of delivering bacteriophages since the bacteriophages are inactivated. When bacteriophages were included inside a CaCO3 core, it was demonstrated that the phage retained activity before and after the dissolution of the CaCO3 particle. From the results of this study, we recommend using CaCO3 microparticles as a container for bacteriophage delivery through the acidic stomach barrier.
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Levanova, L. A., Yu V. Zakharova, A. A. Markovskaya, and L. Yu Otdushkina. "Bacteriophage sensitivity of opportunistic microbiota in children with gut dysbiosis." Fundamental and Clinical Medicine 7, no. 3 (September 30, 2022): 40–45. http://dx.doi.org/10.23946/2500-0764-2022-7-3-40-45.
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Aim. As the activity of bacteriophages is species- and strain-specific, it is necessary to study bacteriophage sensitivity in distinct geographic regions with various disease patterns. Here, we aimed to study the lytic activity of specific commercially available bacteriophages against Klebsiella spp., Proteus spp., and Staphylococcus aureus isolated from the intestines of children with gut dysbiosis.Materials and Methods. Bacteriophage sensitivity was assessed in 315 opportunistic microorganisms (125 Staphylococcus aureus strains, 120 Klebsiella spp. strains, 70 Proteus spp. strains) isolated from the intestinal microbiota of 300 children < 4 years of age with gut dysbiosis. Bacteriophage preparations were produced by Microgen (Russian Federation). The lytic activity of bacteriophages was studied by a drip method on a Muller-Hinton medium by calculating the area of bacterial culture lysis.Results. We found low sensitivity of Klebsiella spp. (37.5% sensitive strains) and Proteus spp. (41.4% sensitive strains) to specific bacteriophages, albeit there were considerable differences between distinct Klebsiella species (Klebsiella pneumoniae, 56.7% sensitive strains; Klebsiella oxytoca, 18.3% sensitive strains, p = 0.03) and Proteus species (Proteus vulgaris, 52.0% strains; Proteus mirabilis, 35.6% strains, p = 0.04). Nevertheless, sensitivity to Staphylococcus aureus was considerably higher (78.4%). In addition, lytic activity of bacteriophages reduced along with the increasing severity of gut dysbiosis.Conclusion. Klebsiella spp. and Proteus spp. isolated from children with dysbiosis have low sensitivity to commercially available bacteriophages. Bacteriophage sensitivity positively correlated with gut dysbiosis.
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Khan, M. A., H. Satoh, T. Mino, H. Katayama, F. Kurisu, and T. Matsuo. "Bacteriophage-host interaction in the enhanced biological phosphate removing activated sludge system." Water Science and Technology 46, no. 1-2 (July 1, 2002): 39–43. http://dx.doi.org/10.2166/wst.2002.0453.
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Bacteriophages were isolated from a laboratory scale enhanced biological phosphate removing (EBPR) activated sludge process, and their host range was examined. Bacterial isolates to host the bacteriophages were isolated from the EBPR activated sludge process. Bacteriophages were eluted from the EBPR activated sludge, enriched by incubation with the bacterial isolates, and then tested for plaque formation on each of the bacterial isolates. Out of 12 bacterial isolates isolated, 4 supported plaque formation. Four bacteriophages were obtained from the plaques. The host range test was conducted with the combination of the bacteriophage isolates and the bacterial isolates. Three of the bacteriophages were found to form plaques on more than one host, and one of them formed plaques on both Gram +ve and Gram −ve bacterial isolates. Two of the four bacteriophages failed to form plaques on their original bacterial host, indicating the existence of mutation on either both or one of the host and the bacteriophage. This study strongly suggests that bacteriophages are an active part of the activated sludge microbial ecosystem, having very complex interaction with their host bacteria.
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Kamtaeja, Somboon, Srinuan Niyom, and Nanthanit Jaruseranee. "Isolation of Biofilm Removing Bacteriophages from the Hot Spring of Mae Chan Fault, Chiang Rai, Northern Thailand." Chiang Mai Journal of Science 51, no. 1 (January 31, 2024): 1–10. http://dx.doi.org/10.12982/cmjs.2024.009.
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T errestrial hot springs offer unique habitats for various bacteriophages, revealing potential reservoirs and a library for antibiotic-resistant and biofilm-removing bacteriophages. This study aimed to identify biofilm-removing bacteriophages as a potential method to eradicate antibiotic-resistant bacteria. Samples were collected from the Mae Chan Fault geothermal sites in Chiang Rai province, north of Thailand. Our bacteriophages, HSPT1 and HSPT2, effectively infect Pseudomonas aeruginosa TISTR1287, as measured by their plaque sizes (3.23 ± 0.26 mm) and (1.14 ± 0.18 mm), respectively. Thermostability analysis reveals that the optimal temperature for bacteriophage HSPT1 is between 20 and 60 oC, while for bacteriophage HSPT2, it is between 20 and 40 oC. Biofilm biomass was significantly reduced by the bacteriophages HSPT1 and HSPT2 treatments (1.42 ± 0.81 and 2.51 ± 0.71, respectively). The study reveals that hot spring bacteriophages effectively remove bacterial biofilms, proving their potential as a new treatment option for antibiotic-resistant bacteria in clinical and tourism settings. These bacteriophages, derived from hot springs, have effectively reduced biofilm-forming microorganisms and multidrug-resistant pathogenic bacteria.
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Li, Jinyu, and John J. Dennehy. "Differential Bacteriophage Mortality on Exposure to Copper." Applied and Environmental Microbiology 77, no. 19 (August 12, 2011): 6878–83. http://dx.doi.org/10.1128/aem.05661-11.
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ABSTRACTMany studies report that copper can be used to control microbial growth, including that of viruses. We determined the rates of copper-mediated inactivation for a wide range of bacteriophages. We used two methods to test the effect of copper on bacteriophage survival. One method involved placing small volumes of bacteriophage lysate on copper and stainless steel coupons. Following exposure, metal coupons were rinsed with lysogeny broth, and the resulting fluid was serially diluted and plated on agar with the corresponding bacterial host. The second method involved adding copper sulfate (CuSO4) to bacteriophage lysates to a final concentration of 5 mM. Aliquots were removed from the mixture, serially diluted, and plated with the appropriate bacterial host. Significant mortality was observed among the double-stranded RNA (dsRNA) bacteriophages Φ6 and Φ8, the single-stranded RNA (ssRNA) bacteriophage PP7, the ssDNA bacteriophage ΦX174, and the dsDNA bacteriophage PM2. However, the dsDNA bacteriophages PRD1, T4, and λ were relatively unaffected by copper. Interestingly, lipid-containing bacteriophages were most susceptible to copper toxicity. In addition, in the first experimental method, the pattern of bacteriophage Φ6 survival over time showed a plateau in mortality after lysates dried out. This finding suggests that copper's effect on bacteriophage is mediated by the presence of water.
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Kargina, T. M., E. I. Sakanyan, D. S. Davydov, and R. L. Parfenyuk. "Elaboration of Pharmacopoeial Quality Standards for Bacteriophage Products." BIOpreparations. Prevention, Diagnosis, Treatment 19, no. 4 (December 11, 2019): 233–41. http://dx.doi.org/10.30895/2221-996x-2019-19-4-233-241.
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Bacteriophages are novel safe and efficacious medicinal products that are used for treatment of intestinal infections and purulent inflammations. The fact that virulent phages can be adapted to fight antibiotic-resistant bacterial strains makes this group of medicines a promising means of treatment of infections associated with medical interventions. The elaboration of quality standards for bacteriophage products will enable alignment of the quality requirements and test methods. There are no monographs on bacteriophage products in pharmacopoeias of other countries, therefore, the development of general chapters on groups of test methods used in bacteriophage quality control and monographs on bacteriophages for the State Pharmacopoeia of the Russian Federation (Ph. Rus.) was a very relevant and timely initiative. The aim of the study was to elaborate pharmacopoeial quality standards for bacteriophages approved in the Russian Federation for therapeutic and prophylactic indications. The authors of the study analysed product specification files and master production records for bacteriophages produced in the Russian Federation. They determined common GMP-compliant production steps, the selection criteria for bacteriophage strains and bacteria production strains, and cultivation and storage conditions. The authors standardised bacteriophage quality parameters and brought the test methods in line with the test procedures described in the Ph. Rus., 14th ed. The study summarised test methods used for identification of bacteriophages and determination of their specific activity. The main results of the study were included into the general monograph «Bacteriophages» and individual monographs on bacteriophage products that were included into the current edition of the Ph. Rus. Further studies and elaboration of new quality standards for mono- and multicomponent bacteriophage products, and the use of such products in clinical practice will improve prophylaxis and treatment of various infectious diseases.
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Bach, S. J., R. P. Johnson, K. Stanford, and T. A. McAllister. "Bacteriophages reduce Escherichia coli O157:H7 levels in experimentally inoculated sheep." Canadian Journal of Animal Science 89, no. 2 (June 1, 2009): 285–93. http://dx.doi.org/10.4141/cjas08083.
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Bacteriophage biocontrol has potential as a means of mitigating the prevalence of Escherichia coli O157:H7 in ruminants. The efficacy of oral administration of bacteriophages for reducing fecal shedding of E. coli O157:H7 by sheep was evaluated using 20 Canadian Arcott rams (50.0 ± 3.0) housed in four rooms (n = 5) in a contained facility. The rams had ad libitum access to drinking water and a pelleted barley-based total mixed ration, delivered once daily. Experimental treatments consisted of administration of E. coli O157:H7 (O157), E. coli O157:H7+bacteriophages (O157+phage), bacteriophages (phage), and control (CON). Oral inoculation of the rams with 109 CFU of a mixture of four nalidixic acid-resistant strains of E. coli O157:H7 was performed on day 0. A mixture of 1010 PFU of bacteriophages P5, P8 and P11 was administered on days -2, -1, 0, 6 and 7. Fecal samples collected on 14 occasions over 21 d were analyzed for E. coli O157:H7, total E. coli, total coliforms and bacteriophages. Sheep in treatment O157+phage shed fewer (P < 0.05) E. coli O157:H7 than did sheep in treatment O157. Populations of total coliforms and total E. coli were similar (P < 0.05) among treatments, implying that bacteriophage lysis of non-target E. coli and coliform bacteria in the gastrointestinal tract did not occur. Bacteriophage numbers declined rapidly over 21 d, which likely reduced the chance of collision between bacteria and bacteriophage. Oral administration of bacteriophages reduced shedding of E. coli O157:H7 by sheep, but a delivery system that would protect bacteriophages during passage through the intestine may increase the effectiveness of this strategy as well as allow phage to be administered in the feed.Key words: Escherichia coli O157:H7, bacteriophage, sheep, environment, coliforms
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Reyneke, Brandon, Benjamin Havenga, Monique Waso-Reyneke, Sehaam Khan, and Wesaal Khan. "Benefits and Challenges of Applying Bacteriophage Biocontrol in the Consumer Water Cycle." Microorganisms 12, no. 6 (June 7, 2024): 1163. http://dx.doi.org/10.3390/microorganisms12061163.
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Bacteria (including disinfection- and antibiotic-resistant bacteria) are abundant in the consumer water cycle, where they may cause disease, and lead to biofouling and infrastructure damage in distributions systems, subsequently resulting in significant economic losses. Bacteriophages and their associated enzymes may then offer a biological control solution for application within the water sector. Lytic bacteriophages are of particular interest as biocontrol agents as their narrow host range can be exploited for the targeted removal of specific bacteria in a designated environment. Bacteriophages can also be used to improve processes such as wastewater treatment, while bacteriophage-derived enzymes can be applied to combat biofouling based on their effectiveness against preformed biofilms. However, the host range, environmental stability, bacteriophage resistance and biosafety risks are some of the factors that need to be considered prior to the large-scale application of these bacterial viruses. Characteristics of bacteriophages that highlight their potential as biocontrol agents are thus outlined in this review, as well as the potential application of bacteriophage biocontrol throughout the consumer water cycle. Additionally, the limitations of bacteriophage biocontrol and corresponding mitigation strategies are outlined, including the use of engineered bacteriophages for improved host ranges, environmental stability and the antimicrobial re-sensitisation of bacteria. Finally, the potential public and environmental risks associated with large-scale bacteriophage biocontrol application are considered, and alternative applications of bacteriophages to enhance the functioning of the consumer water cycle, including their use as water quality or treatment indicators and microbial source tracking markers, are discussed.
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Adhikari, Niran, and Krishna P. Acharya. "Effectiveness of Bacteriophage Therapy in Field Conditions and Possible Future Applications." Current Pharmaceutical Biotechnology 21, no. 5 (April 29, 2020): 364–73. http://dx.doi.org/10.2174/1389201021666191217111156.
Texte intégralRésumé :
Background: Bacteriophages are viruses, which are obligate parasites of specific bacteria for the completion of their lifecycle. Bacteriophages could be the possible alternative to antibioticresistant bacterial diseases. With this objective, extensive research in different fields is published which are discussed in this article. Results: After a review of bacteriophage therapy, bacteriophages were found to be effective against the multidrug-resistant bacteria individually or synergistically with antibiotics. They were found to be more effective, even better than the bacteria in the development of a vaccine. Conclusion: Thus, bacteriophage therapy offers promising alternatives in the treatment of antibioticresistant bacteria in different fields. However, their effectiveness is determined by a triad of bacteriophages (type & quantity), host (bacteria) and environmental factors.
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Kochetova, T. A., V. V. Yuskevich, F. M. Zurabov, G. T. Sadykova, P. V. Medvedev, and V. M. Popova. "Isolation of novel <i>Actinomyces oris</i> and <i>Aggregatibacter actinomycetemcomitans</i> bacteriophages and study of their biological characteristics <i>in vitro</i>." Biological Products. Prevention, Diagnosis, Treatment 24, no. 1 (March 1, 2024): 103–16. http://dx.doi.org/10.30895/2221-996x-2024-24-1-103-116.
Texte intégralRésumé :
SCIENTIFIC RELEVANCE. The incidence of periodontal infections with antibiotic-resistant strains of Actinomyces oris and Aggregatibacter actinomycetemcomitans capable of forming biofilms in the oral cavity is increasing, and the effectiveness of antimicrobials against biofilms is insufficient. Therefore, the isolation of bacteriophages active against A. oris and Ag. actinomycetemcomitans is an urgent task.AIM. This study aimed to isolate bacteriophages active against A. oris and Ag. actinomycetemcomitans, study their biological properties, and select optimum culture conditions providing pure lines and high titres of bacteriophages.MATERIALS AND METHODS. Bacteriophages were isolated from biosamples of saliva, dental plaque, and periodontal pocket contents. The study determined bacteriophage characteristics, including the optimum multiplicity of infection, phage–cell system cultivation time, resistance to various temperatures and pH, and storage stability. Bacteriophage morphology was studied using transmission electron microscopy. Negative colony morphology, lytic activity, host range, and specificity were assessed using spot testing and the Gratia method. Bacterial strains were obtained from the strain collection of the Micromir research and production centre.RESULTS. The authors isolated and studied 3 novel bacteriophages active against A. oris (vB_AorP_1/G-12, vB_AorP_2/Ch-28, and vB_AorP_3/Bl-35) and 1 bacteriophage active against Ag. actinomycetemcomitans (vB_AacS_1/Dc-1). The A. oris bacteriophages were classified as podoviruses, and the vB_AacS_1/Dc-1 bacteriophage was classified as a siphovirus. The phages formed completely transparent round plaques without a halo, with a diameter ranging from 0.8±0.1 to 4.0±0.2 mm. The optimum parameters established to obtain pure phages with maximum titres included a multiplicity of infection of 0,1–10 and phage–cell system cultivation time of 8–12 hours. The study demonstrated the ability of A. oris bacteriophages to lyse Actinomyces naeslundii strains. Of the 15 A. oris bacteriophage strains studied, vB_AorP_1/G-12, vB_AorP_2/Ch-28, and vB_AorP_3/Bl-35 lysed 10, 8, and 12 bacterial strains, respectively. The vB_AacS_1/Dc-1 phage isolate exhibited lytic activity against both tested strains of Ag. actinomycetemcomitans. The studied phages demonstrated stability under abiotic stress and long-term storage conditions.CONCLUSIONS. The authors isolated 3 novel bacteriophages active against A. oris and 1 bacteriophage active against Ag. actinomycetemcomitans and studied their biological properties. The isolated bacteriophages are promising as candidates for further research using clinical strains and whole-genome sequencing.
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Nishiyama, Hiroki, Hisashi Endo, Romain Blanc-Mathieu, and Hiroyuki Ogata. "Ecological Structuring of Temperate Bacteriophages in the Inflammatory Bowel Disease-Affected Gut." Microorganisms 8, no. 11 (October 27, 2020): 1663. http://dx.doi.org/10.3390/microorganisms8111663.
Texte intégralRésumé :
The aim of this study was to elucidate the ecological structure of the human gut temperate bacteriophage community and its role in inflammatory bowel disease (IBD). Temperate bacteriophages make up a large proportion of the human gut microbiota and are likely to play a role in IBD pathogenesis. However, many of these bacteriophages await characterization in reference databases. Therefore, we conducted a large-scale reconstruction of temperate bacteriophage and bacterial genomes from the whole-metagenome sequence data generated by the IBD Multi’omics Database project. By associating phages with their hosts via genome comparisons, we found that temperate bacteriophages infect a phylogenetically wide range of bacteria. The majority of variance in bacteriophage community composition was explained by variation among individuals, but differences in the abundance of temperate bacteriophages were identified between IBD and non-IBD patients. Of note, in active ulcerative colitis patients, temperate bacteriophages infecting Bacteroides uniformis and Bacteroides thetaiotaomicron—two species experimentally proven to be beneficial to gut homeostasis—were over-represented, whereas their hosts were under-represented in comparison with non-IBD patients. Supporting the mounting evidence that gut viral community plays a vital role in IBD, our results show potential association between temperate bacteriophages and IBD pathogenesis.
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Roseline, Felicia, Diana Elizabeth Waturangi, and Yogiara Y. "ISOLATION, CHARACTERIZATION, AND APPLICATION OF BACTERIOPHAGES AGAINST SEVERAL FOOD SPOILAGE BACTERIA: Bacillus subtilis, Bacillus cereus, AND Shewanella Putrefaciens." Bacterial Empire 4, no. 2 (April 13, 2021): e263. http://dx.doi.org/10.36547/be.263.
Texte intégralRésumé :
Introduction: Bacteriophages can be the natural alternative method to prevent food spoilage caused by bacteria. This research was conducted to isolate bacteriophages from a soil sample, retail food, and wastewater from fish and then the bacteriophages will be characterized for their activity against several food spoilage bacteria, such as Bacillus cereus, Bacillus subtilis, and Shewanella putrefaciens and will be further investigated for application as food preservation. Experimental: B. cereus (Atma Jaya culture collection), B. subtilis ATCC 6633, and S. putrefaciens ATCC 8071 were used for bacteriophage isolation. Food samples (rice, pasta, tofu, tempeh), soil samples (black soil and laterite), and wastewater sample of freshwater fish and seawater fish were used in this research. The overall process consists of eight steps: inoculum preparation, sample collection, bacteriophage isolation, purification and enrichment, titer determination, host range determination, the efficiency of plating (EOP), and bacteriophage application. Results: A total of four bacteriophages were isolated with B. cereus, B. subtilis, and S. putrefaciens as host bacteria. Bacteriophage titers observed around 109 PFU mL-1. Bacteriophages that isolated with B. cereus and B. subtilis as host bacteria tend to have high EOP with the same species bacteria. All the Bacillus phages (S1-BC, S2-BC, and S1-BS) can reduce the Bacillus species bacteria concentration for more than 90%. Conclusion: Refers to their activity, the isolated bacteriophages in this study might have a great prospect to be used as food biocontrol and also can be further tested to make a phage cocktail.
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Hu, Yang, Bader Al Shaaer, Lu Liang, and Ian F. Connerton. "Campylobacter Bacteriophage Infection at Refrigeration Temperatures." Applied Microbiology 3, no. 4 (December 13, 2023): 1392–406. http://dx.doi.org/10.3390/applmicrobiol3040094.
Texte intégralRésumé :
The application of bacteriophages to control foodborne bacterial pathogens in foods has gained traction in recent years. Poultry meat is a major source of Campylobacter jejuni, and a target for the application of bacteriophages. To offer the prospect of a post-harvest control measure, the bacteriophage must function at refrigeration temperatures, where C. jejuni does not grow but can survive. Here, we report actions of three classes of Campylobacter bacteriophage at 4 °C. The pre-incubation of broth cultures at 4 °C before a shift to 42 °C under conditions that support the growth of the host bacteria revealed differences in the time to lysis compared with cultures incubated at 42 °C. The pre-adsorption of the bacteriophage to a sub-population of bacteria is consistent with the observation of asynchronous infection. To ascertain whether the bacteriophages adsorb and infect (the commitment to replicate), we investigated bacteriophage transcription at 4 °C. RNA transcripts for all the bacteriophage host combinations were detected after 15 min, indicating that the interaction is not merely passive. Bacteriophages can infect C. jejuni at refrigeration temperatures, but the infection does not proceed to lysis in the absence of host cell division.
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Shruti, Sinha, and Srivastava* Soumya. "Bacteriophage and Phage-Therapy: An Alternative to Antibiotics." eLifePress 1, no. 1 (October 6, 2020): 21–27. https://doi.org/10.5281/zenodo.4307923.
Texte intégralRésumé :
Bacteriophages are known for a century but their use in therapy to cure bacterial infection is still unknown. The working on bacteriophage investigation started about a century ago with their discovery by the English microbiologist Twort in 1915. The continuous growth of resistance in bacteria for various diseases and infections has caused renewing in bacteriophage therapy against bacterial infections. Lytic bacteriophages are those bacteriophages that can kill bacteria that are resistant to antibiotics by the end of their lytic cycle. Bacteriophages use proteins for the lysis of bacteria, termed as the Holin-lysin system. Research is going on globally on therapeutic uses of bacteriophages as less is known about phage therapy to combat bacterial diseases and infections. This therapy has attracted many scientists as difficulty in curing bacterial infection is at the peak. This difficulty is arising mainly in antibiotic-resistance bacteria in contemporary medicine.
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Khan, Muhammad Fayaz, Aamer Ali Khattak, Afshan Saleem, Muhammad Rizwan, Muhammad Asif, and Iqbal Ahmad Alvi. "Efficient Reduction of Pseudomonas aeruginosa Biofilms Using the Myoviridae Lytic Bacteriophage vBPaeM MLG." Lahore Garrison University Journal of Life Sciences 7, no. 03 (September 25, 2023): 262–79. http://dx.doi.org/10.54692/lgujls.2023.0703275.
Texte intégralRésumé :
Pseudomonas aeruginosa biofilm infections pose significant challenges in clinical settings due to their increased resistance to conventional antibiotics. Bacteriophages, viruses that infect and kill bacteria, have emerged as promising agents for combating biofilm-related infections. This study aimed to isolate and characterize a potent bacteriophage with antibiofilm activity against P. aeruginosa. Hospital sewage was utilized to isolate a bacteriophage targeting P. aeruginosa. Quantification of phages was conducted through spot tests and doublelayer agar methods. The stability of the isolated phage was assessed under varying pH and temperature conditions. Furthermore, the bacteriophage's ability to reduce bacterial growth and exhibit antibiofilm activity was evaluated at different Multiplicity of Infection (MOI) levels. The isolated bacteriophage, named MLG, was identified as a member of the Myoviridae family within the Caudovirales order. MLG effectively reduced bacterial growth over a 14-hour period. It displayed tolerance to a pH range of 5 to 9 and temperatures spanning 25 to 60°C. Moreover, MLG demonstrated efficient inhibition of biofilm formation across various MOI levels. Given its demonstrated in vitro capacity for bacterial growth reduction and antibiofilm activity, MLG holds potential for combatting P. aeruginosa biofilm infections. This study suggests a promising avenue for the development of alternative antibiofilm strategies using bacteriophages.
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Brišar, Nuša, Katja Šuster, Simona Kranjc Brezar, Robert Vidmar, Marko Fonović, and Andrej Cör. "An Engineered M13 Filamentous Nanoparticle as an Antigen Carrier for a Malignant Melanoma Immunotherapeutic Strategy." Viruses 16, no. 2 (February 1, 2024): 232. http://dx.doi.org/10.3390/v16020232.
Texte intégralRésumé :
Bacteriophages, prokaryotic viruses, hold great potential in genetic engineering to open up new avenues for vaccine development. Our study aimed to establish engineered M13 bacteriophages expressing MAGE-A1 tumor peptides as a vaccine for melanoma treatment. Through in vivo experiments, we sought to assess their ability to induce robust immune responses. Using phage display technology, we engineered two M13 bacteriophages expressing MAGE-A1 peptides as fusion proteins with either pVIII or pIIII coat proteins. Mice were intraperitoneally vaccinated three times, two weeks apart, using two different engineered bacteriophages; control groups received a wild-type bacteriophage. Serum samples taken seven days after each vaccination were analyzed by ELISA assay, while splenocytes harvested seven days following the second boost were evaluated by ex vivo cytotoxicity assay. Fusion proteins were confirmed by Western blot and nano-LC-MS/MS. The application of bacteriophages was safe, with no adverse effects on mice. Engineered bacteriophages effectively triggered immune responses, leading to increased levels of anti-MAGE-A1 antibodies in proportion to the administered bacteriophage dosage. Anti-MAGE-A1 antibodies also exhibited a binding capability to B16F10 tumor cells in vitro, as opposed to control samples. Splenocytes demonstrated enhanced CTL cytotoxicity against B16F10 cells. We have demonstrated the immunogenic capabilities of engineered M13 bacteriophages, emphasizing their potential for melanoma immunotherapy.
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Rai, Akanksha, and Krishna Khairnar. "Initial Survey of Staphylococcus Bacteriophages and Simple Modifications in the Enrichment Method for Enhancing Plaques." Research Journal of Biotechnology 17, no. 7 (June 25, 2022): 130–33. http://dx.doi.org/10.25303/1707rjbt1300133.
Texte intégralRésumé :
Isolation of bacteriophages against Staphylococcus aureus is difficult when compared to the bacteriophages of other genera. We did a preliminary survey for the presence of bacteriophages of S. aureus and Escherichia coli in the environmental water samples. We did not get bacteriophages against S. aureus, but bacteriophages against E. coli were ample. Subsequently, a river-water sample was taken and through the enrichment method with some modifications, we got a bacteriophage against a methicillin-resistant S. aureus. Here, we are reporting simple changes in the enrichment method to enhance plaques that have an extremely tiny and turbid morphology. This can be useful for researchers facing difficulty in finding lytic bacteriophages from water samples.
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Kurtböke, İpek, Nina Chanishvili, and Jeremy J. Barr. "Bacteriophages." Microbiology Australia 40, no. 1 (2019): 3. http://dx.doi.org/10.1071/ma19002.
Texte intégralRésumé :
In order to avoid a return to the pre-antibiotic era, alternative treatments to combat microbial diseases are urgently needed. In this context, bacteriophages, which have been used effectively in distant parts of the world during the cold war era, are now gaining significant interest in the West. This special issue of the Microbiology Australia thus focusses on bacteriophages with contributions from Australia and from the members of the Expert round table on acceptance and re-implementation of bacteriophage therapy.
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Kharaeva, Z. F., M. Sh Mustafaev, L. Z. Blieva, E. B. Barokova, S. M. Mustafaeva, and S. A. Dyshekova. "Evaluation of sensitivity to bacteriophages of strains isolated from children with congenital malformations of the maxillofacial region." REPORTS ADYGE (CIRCASSIAN) INTERNATIONAL ACADEMY OF SCIENCES 20, no. 1 (2020): 40–45. http://dx.doi.org/10.47928/1726-9946-2020-20-1-40-45.
Texte intégralRésumé :
Bacteriophage are used in clinical practice along with antibiotics. It is known that in many cases phage drugs are superior to other antibacterial drugs in their activity against antibiotic-resistant pathogens. Bacteriophages do not cause toxic or allergic side effects and have no contraindications.The use of bacteriophage preparations stimulates the activation of adaptive and innate immune factors, so phage therapy is particularly effective in the treatment of chronic inflammatory diseases against the background of immunosuppressive States. Bacteriophages do not interfere with the implementation of the therapeutic effect of other drugs (antibiotics, probiotics, synbiotics) and are not sensitive to their effects. The paper evaluates the sensitivity of different types of staphylococci and streptococci to specific bacteriophages, as well as to sextaphage - polyvalent piobacteriophage. In the course of research, it was found that bacterial cultures of Staphylococcus aureus showed a fairly high sensitivity to sextaphage, to which 83,3% (10 strains) of the total number of studied strains of this species were susceptible. Sensitivity to bacteriophages in Staphylococcus epidermidis strains was low. Bacterial strains of Streptococcus pyogenes showed greater susceptibility to streptococcal phage than to sextaphage. 87,5% of the strains were susceptible to streptococcal bacteriophage. Bacterial cultures of Streptococcus salivarius showed moderate susceptibility to bacteriophages.
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Sjahriani, Tessa, Eddy Bagus Wasito, and Wiwiek Tyasningsih. "Isolation and Identification of Escherichia coli O157:H7 Lytic Bacteriophage from Environment Sewage." International Journal of Food Science 2021 (August 11, 2021): 1–11. http://dx.doi.org/10.1155/2021/7383121.
Texte intégralRésumé :
Escherichia coli O157:H7 is one of the pathogenic bacteria causing foodborne disease. The use of lytic bacteriophages can be a good solution to overcome the disease. This study is aimed at isolating lytic bacteriophages from environmental sewage with E. coli O157:H7 bacterial cells. The sample used in this study was eight bacteriophages, and the technique used in identifying E. coli O157:H7 carriers of the stx1 and stx2 genes was PCR. The double layer plaque technique was used to classify bacteriophages. Plaque morphology, host specificity, and electron micrograph were used to identify the bacteriophages. The result obtained plaque morphology as a clear zone with the largest diameter size of 3.5 mm. Lytic bacteriophage could infect E. coli O157:H7 at the highest titer of 10 × 10 8 PFU / mL . Bacteriophages have been identified as Siphoviridae and Myoviridae. Phage 3, phage 4, and phage 8 could infect Atypical Diarrheagenic E. coli 1 (aDEC1) due to their host specificity. The Friedman statistical tests indicate that lytic bacteriophage can significantly lyse E. coli O157:H7 ( p = 0.012 ). The lysis of E. coli O157:H7 by phage 1, phage 2, phage 3, and phage 5 bacteriophages was statistically significant, according to Conover’s posthoc test ( p < 0.05 ). The conclusion obtained from this study is that lytic bacteriophages from environmental sewage could lyse E. coli O157:H7. Therefore, it could be an alternative biocontrol agent against E. coli O157:H7 that contaminates food causing foodborne disease.
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Baqer, Abeer Ameen, Kokxin Fang, Norfarhan Mohd-Assaad, Siti Noor Adnalizawati Adnan, and Norefrina Shafinaz Md Md Nor. "In Vitro Activity, Stability and Molecular Characterization of Eight Potent Bacteriophages Infecting Carbapenem-Resistant Klebsiella Pneumoniae." Viruses 15, no. 1 (December 30, 2022): 117. http://dx.doi.org/10.3390/v15010117.
Texte intégralRésumé :
Background: Members of the genus Klebsiella are among the leading microbial pathogens associated with nosocomial infection. The increased incidence of antimicrobial resistance in these species has propelled the need for alternate/combination therapeutic regimens to aid clinical treatment, including bacteriophage therapy. Bacteriophages are considered very safe and effective in treating bacterial infections. In this study, we characterize eight lytic bacteriophages that were previously isolated by our team against carbapenem-resistant Klebsiella pneumoniae. Methods: The one-step-growth curves, stability and lytic ability of eight bacteriophages were characterized. Restriction fragment length polymorphism (RFLP), random amplification of polymorphic DNA (RAPD) typing analysis and protein profiling were used to characterize the microbes at the molecular level. Phylogenetic trees of four important proteins were constructed for the two selected bacteriophages. Results and conclusions: All eight bacteriophages showed high efficiency for reducing bacterial concentration with high stability under different physical and chemical conditions. We found four major protein bands out of at least ten 15–190 KDa bands that were clearly separated by SDS-PAGE, which were assumed to be the major head and tail proteins. The genomes were found to be dsDNA, with sizes of approximately 36–87 Kb. All bacteriophages reduced the optical density of the planktonic K. pneumoniae abruptly, indicating great potential to reduce K. pneumoniae infection. In this study, we have found that tail fiber protein can further distinguished closely related bacteriophages. The characterised bacteriophages showed promising potential as candidates against carbapenem-resistant Klebsiella pneumoniae via bacteriophage therapy.
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Monarchovich, M. A., O. A. Galaburda, A. A. Arashkova, N. V. Sverchkova, and E. I. Kolomiets. "ISOLATION AND CHARACTERISTICS OF BACTERIOPHAGES SANITARY-INDICATIVE MICROORGANISMS." Eurasian Journal of Applied Biotechnology, no. 2 (July 9, 2022): 25–32. http://dx.doi.org/10.11134/btp.2.2022.4.
Texte intégralRésumé :
Isolated phages showed activity toward opportunistic and pathogenic bacteria of genera Escherichia (K3P1, K3P2, BIM BV-44 D) and Pseudomonas (PsP1), formed lysis zones shaped as negative homogeneous colonies with a clear-cut even edge (K3P1, PsP1, BIM BV -44 D), or negative colonies with a peripheral zone of partial lysis (K3P2). The diameter of phage plaques varied from 0,5–1,5 mm. Lytic activity spectrum of phage isolates was investigated. It was found that the studied bacteriophages displayed species specificity. Bacteriophages K3P1, K3P2 were distinguished by the highest lytic range. Differences in the isolated bacteriophages according to restriction profiles were revealed. Bacteriophage distinctions in restriction profiles were revealed. Interaction of bacteriophages with cells of bacteria of E. coli and Ps. aeruginosa was explored. The tested bacteriophage strains demonstrating lytic activity toward sanitary-indicative bacterial species may find use as disinfectants in detergents.
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OTTER, JONATHAN A., and ANDREA BUDDE-NIEKIEL. "Hydrogen Peroxide Vapor: A Novel Method for the Environmental Control of Lactococcal Bacteriophage†." Journal of Food Protection 72, no. 2 (February 1, 2009): 412–14. http://dx.doi.org/10.4315/0362-028x-72.2.412.
Texte intégralRésumé :
Bacteriophage contamination can be problematic, especially in industrial settings. We examined the in vitro efficacy of hydrogen peroxide vapor (HPV) for the inactivation of two lactococcal bacteriophages dried onto stainless steel discs. A more than 6-log reduction was achieved on both bacteriophages compared with unexposed controls by 50 min of HPV exposure in an isolator. HPV might be useful for the environmental control of bacteriophages.
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Doore, Sarah M., Jason R. Schrad, William F. Dean, John A. Dover, and Kristin N. Parent. "ShigellaPhages Isolated during a Dysentery Outbreak Reveal Uncommon Structures and Broad Species Diversity." Journal of Virology 92, no. 8 (February 7, 2018): e02117-17. http://dx.doi.org/10.1128/jvi.02117-17.
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ABSTRACTIn 2016, Michigan experienced the largest outbreak of shigellosis, a type of bacillary dysentery caused byShigellaspp., since 1988. Following this outbreak, we isolated 16 novelShigella-infecting bacteriophages (viruses that infect bacteria) from environmental water sources. Most well-known bacteriophages infect the common laboratory speciesEscherichia coliandSalmonella enterica, and these phages have built the foundation of molecular and bacteriophage biology. Until now, comparatively few bacteriophages were known to infectShigellaspp., which are close relatives ofE. coli. We present a comprehensive analysis of these phages' host ranges, genomes, and structures, revealing genome sizes and capsid properties that are shared by very few previously described phages. After sequencing, a majority of theShigellaphages were found to have genomes of an uncommon size, shared by only 2% of all reported phage genomes. To investigate the structural implications of this unusual genome size, we used cryo-electron microscopy to resolve their capsid structures. We determined that these bacteriophage capsids have similarly uncommon geometry. Only two other viruses with this capsid structure have been described. Since most well-known bacteriophages infectEscherichiaorSalmonella, our understanding of bacteriophages has been limited to a subset of well-described systems. Continuing to isolate phages using nontraditional strains of bacteria can fill gaps that currently exist in bacteriophage biology. In addition, the prevalence ofShigellaphages during a shigellosis outbreak may suggest a potential impact of human health epidemics on local microbial communities.IMPORTANCEShigellaspp. bacteria are causative agents of dysentery and affect more than 164 million people worldwide every year. Despite the need to combat antibiotic-resistantShigellastrains, relatively fewShigella-infecting bacteriophages have been described. By specifically looking forShigella-infecting phages, this work has identified new isolates that (i) may be useful to combatShigellainfections and (ii) fill gaps in our knowledge of bacteriophage biology. The rare qualities of these new isolates emphasize the importance of isolating phages on “nontraditional” laboratory strains of bacteria to more fully understand both the basic biology and diversity of bacteriophages.
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Gomez, Mellissa, Alexandra Szewczyk, Jake Szamosi, Vincent Leung, Carlos Filipe, and Zeinab Hosseinidoust. "Stress Exposure of Evolved Bacteriophages under Laboratory versus Food Processing Conditions Highlights Challenges in Translatability." Viruses 15, no. 1 (December 30, 2022): 113. http://dx.doi.org/10.3390/v15010113.
Texte intégralRésumé :
Bacterial viruses, or bacteriophages, are highly potent, target-specific antimicrobials. Bacteriophages can be safely applied along the food production chain to aid control of foodborne pathogens. However, bacteriophages are often sensitive to the environments encountered in food matrices and under processing conditions, thus limiting their applicability. We sought to address this challenge by exposing commercially available Listeria monocytogenes bacteriophage, P100, to three stress conditions: desiccation, elevated temperature, and low pH, to select for stress-resistant bacteriophages. The stressed bacteriophage populations lost up to 5.1 log10 in infectivity; however, the surviving subpopulation retained their stress-resistant phenotype through five passages with a maximum of 2.0 log10 loss in infectivity when exposed to the same stressor. Sequencing identified key mutation regions but did not reveal a clear mechanism of resistance. The stress-selected bacteriophage populations effectively suppressed L. monocytogenes growth at a modest multiplicity of infection of 0.35–0.43, indicating no trade-off in lytic ability in return for improved survivability. The stressed subpopulations were tested for survival on food grade stainless steel, during milk pasteurization, and within acidic beverages. Interestingly, air drying on stainless steel and pasteurization in milk led to significantly less stress and titer loss in bacteriophage compared to similar stress under model lab conditions. This led to a diminished benefit for stress-selection, thus highlighting a major challenge in real-life translatability of bacteriophage adaptational evolution.
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Jamaledin, Rezvan, Rossella Sartorius, Concetta Di Natale, Raffaele Vecchione, Piergiuseppe De Berardinis, and Paolo Antonio Netti. "Recombinant Filamentous Bacteriophages Encapsulated in Biodegradable Polymeric Microparticles for Stimulation of Innate and Adaptive Immune Responses." Microorganisms 8, no. 5 (April 29, 2020): 650. http://dx.doi.org/10.3390/microorganisms8050650.
Texte intégralRésumé :
Escherichia coli filamentous bacteriophages (M13, f1, or fd) have attracted tremendous attention from vaccinologists as a promising immunogenic carrier and vaccine delivery vehicle with vast possible applications in the development of vaccines. The use of fd bacteriophage as an antigen delivery system is based on a modification of bacteriophage display technology. In particular, it is designed to express multiple copies of exogenous peptides (or polypeptides) covalently linked to viral capsid proteins. This study for the first time proposes the use of microparticles (MPs) made of poly (lactic-co-glycolic acid) (PLGA) to encapsulate fd bacteriophage. Bacteriophage–PLGA MPs were synthesized by a water in oil in water (w1/o/w2) emulsion technique, and their morphological properties were analyzed by confocal and scanning electron microscopy (SEM). Moreover, phage integrity, encapsulation efficiency, and release were investigated. Using recombinant bacteriophages expressing the ovalbumin (OVA) antigenic determinant, we demonstrated the immunogenicity of the encapsulated bacteriophage after being released by MPs. Our results reveal that encapsulated bacteriophages are stable and retain their immunogenic properties. Bacteriophage-encapsulated PLGA microparticles may thus represent an important tool for the development of different bacteriophage-based vaccine platforms.
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Lisa Navitasari, Tri Joko, Rudi Hari Murti, and Triwidodo Arwiyanto. "Aplikasi Actinomycetes dan Bakteriofag pada Tomat Sambung untuk Mengendalikan Penyakit Layu Bakteri Ralstonia solanacearum dan Meningkatkan Hasil Buah." Jurnal Ilmu Pertanian Indonesia 27, no. 4 (October 7, 2022): 521–27. http://dx.doi.org/10.18343/jipi.27.4.527.
Texte intégralRésumé :
Ralstonia solanacearum (Smith) is a soil-borne pathogen that causes bacterial wilt disease and is a complex species in races, biovars, phylotypes, and strains of various pathogenicities. As a result, the pathogen is difficult to control. An alternative control is by applying actinomycetes and bacteriophages on tomato grafted with resistant rootstock. This study aims to find the best combination in controlling bacterial wilt disease among grafted tomato plants and/or actinomycetes and/or bacteriophage treatments to increase yields. The graftings were between Amelia (East West, Indonesia) or H7996 (AVRDC) as rootstocks, and Servo (East West, Indonesia) as the susceptible scion. The grafting used the tube method, and the experimental design was a randomized completely block design with the grafted plants treated by actinomycetes and/or bacteriophages with three replications. The results indicated that actinomycetes application on plants grafted with Amelia rootstock or H7996 and the application of bacteriophages on susceptible varieties (Servo) could be the best alternative treatment in controlling the bacterial wilt disease. The susceptible varieties with the actinomycetes or bacteriophages application could even increase fruit yields higher than the grafted tomatoes treated with actinomycetes or bacteriophages. In fact, the susceptible tomato varieties with bacteriophage treatment showed high fruit yield.
 
 Keywords: actinomycetes, bacteriophages, bacterial wilt disease, fruit yield, Ralstonia solanacearum
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Sturino, Joseph M., and Todd R. Klaenhammer. "Expression of Antisense RNA Targeted against Streptococcus thermophilus Bacteriophages." Applied and Environmental Microbiology 68, no. 2 (February 2002): 588–96. http://dx.doi.org/10.1128/aem.68.2.588-596.2002.
Texte intégralRésumé :
ABSTRACT Antisense RNA complementary to a putative helicase gene (hel3.1) of a cos-type Streptococcus thermophilus bacteriophage was used to impede the proliferation of a number of cos-type S. thermophilus bacteriophages and one pac-type bacteriophage. The putative helicase gene is a component of the Sfi21-type DNA replication module, which is found in a majority of the S. thermophilus bacteriophages of industrial importance. All bacteriophages that strongly hybridized a 689-bp internal hel3.1 probe were sensitive to the expression of antisense hel3.1 RNA. A 40 to 70% reduction in efficiency of plaquing (EOP) was consistently observed, with a concomitant decrease in plaque size relative to that of the S. thermophilus parental strain. When progeny were released, the burst size was reduced. Growth curves of S. thermophilus NCK1125, in the presence of variable levels of bacteriophage κ3, showed that antisense hel3.1 conferred protection, even at a multiplicity of infection of approximately 1.0. When the hel3.1 antisense RNA cassette was expressed in cis from the κ3-derived phage-encoded resistance (PER) plasmid pTRK690::ori3.1, the EOP for bacteriophages sensitive to PER and antisense targeting was reduced to between 10−7 and 10−8, beyond the resistance conferred by the PER element alone (less than 10−6). These results illustrate the first successful applications of antisense RNA and explosive delivery of antisense RNA to inhibit the proliferation of S. thermophilus bacteriophages.
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Gumbatova, L. A., E. V. Lebedeva, T. A. Sergeeva, B. I. Aslanov, S. A. Gordeeva, and D. A. Gusev. "Possibilities of rational application of bacteriophages in the therapy of infections caused by polyresistant strains of Klebsiella pneumoniae." Journal Infectology 16, no. 4 (January 16, 2025): 91–98. https://doi.org/10.22625/2072-6732-2024-16-4-91-98.
Texte intégralRésumé :
The issue of combating antimicrobial resistance has been relevant for several decades, since the arsenal of effective antibiotics used in infectious diseases is significantly reduced, and the development of new antibacterial drugs is significantly difficult and expensive. At the same time, the possibility of widespread use of bacteriophages in hospital settings is being discussed.Goal. Evaluation of the sensitivity to bacteriophages of hospital strains of K.pneumoniae isolated from patients in the departments of surgery and intensive care and intensive care of the Structure Clinical Infectious Disease Hospital named after S.P.Botkin.Materials and methods. The activity of bacteriophage preparations “Sextafag” (series p158, p220, p242), “Klebsiell polyvalent bacteriophage” (series y04, y07, y10, y16), “Polyvalent Pyobacteriophage purified” (series y10, y291022) (Manufacturer: NPO Microgen JSC, Moscow) was determined by preparing suspensions of microorganisms, their sowing on nutrient media with subsequent application of bacteriophages, taking into account and interpreting the results.Results. The majority of polyresistant K.pneumoniae strains showed sensitivity to the presented bacteriophage preparations, which allows them to be considered as additional antibacterial agents for the treatment of these groups of patients.Conclusion. The presented results of the study showed that hospital polyand panresistant strains of K.pneumoniae are sensitive to preparations of monoand polyvalent bacteriophages, which can be considered as a potential alternative in conditions of antibiotic resistance. The study did not reveal a link between the antibiotic resistance profile of the culture and sensitivity to bacteriophages.
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Davydov, D. S., R. L. Parfenyuk, Z. V. Durmanova, and A. A. Movsesyants. "Basic Requirements for the Procedure for Maintaining Collections of Industrial Strains of Bacteriophages." Problems of Particularly Dangerous Infections, no. 4 (December 22, 2024): 146–49. https://doi.org/10.21055/0370-1069-2024-4-146-149.
Texte intégralRésumé :
The development and implementation of biological drugs based on bacteriophages is one of the elements of the “Strategy for Preventing the Spread of Antimicrobial Resistance in the Russian Federation for the Period of up to 2030”, approved by the Decision of the Government of the Russian Federation, dated September 25, 2017 No. 2045-r. A prerequisite for the implementation of the objectives of the Strategy is the creation of banks of hospital strains of microorganisms and banks of relevant bacteriophages. The aim of the work was to determine the basic requirements for the procedure for maintaining a collection of industrial strains of bacteriophages. Materials and methods. An analysis of regulatory documents has been carried out, where goals, objectives, rules for the creation and use of collections of pathogenic microorganisms and viruses are stated, and the requirements for the quality of therapeutic and prophylactic preparations of bacteriophages are set. Information materials containing up-to-date information on the biological properties of bacteriophages that are important for their therapeutic use are considered. Results and discussion. Maintaining a production collection of bacteriophages is characterized by certain features that must be taken into account when crea ting therapeutic and prophylactic preparations of bacteriophages that correspond to the current dynamics of variability of clinical bacterial strains. To ensure the clinical efficacy and genetic safety of phage therapy, bacteriophage preparations should contain bacteriophages that are identified and characterized by morphological, biological, and genetic features. Bacteriophage preparations should be adapted to epidemiologically significant pathogens of purulent-inflammatory and intestinal infections.
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Connerton, P. L., C. M. Loc Carrillo, C. Swift, E. Dillon, A. Scott, C. E. D. Rees, C. E. R. Dodd, J. Frost, and I. F. Connerton. "Longitudinal Study of Campylobacter jejuni Bacteriophages and Their Hosts from Broiler Chickens." Applied and Environmental Microbiology 70, no. 7 (July 2004): 3877–83. http://dx.doi.org/10.1128/aem.70.7.3877-3883.2004.
Texte intégralRésumé :
ABSTRACT A longitudinal study of bacteriophages and their hosts was carried out at a broiler house that had been identified as having a population of Campylobacter-specific bacteriophages. Cloacal and excreta samples were collected from three successive broiler flocks reared in the same barn. Campylobacter jejuni was isolated from each flock, whereas bacteriophages could be isolated from flocks 1 and 2 but were not isolated from flock 3. The bacteriophages isolated from flocks 1 and 2 were closely related to each other in terms of host range, morphology, genome size, and genetic content. All Campylobacter isolates from flock 1 were genotypically indistinguishable by pulsed-field gel electrophoresis (PFGE). PFGE and multilocus sequence typing indicated that this C. jejuni type was maintained from flock 1 to flock 2 but was largely superseded by three genetically distinct C. jejuni types insensitive to the resident bacteriophages. All isolates from the third batch of birds were insensitive to bacteriophages and genotypically distinct. These results are significant because this is the first study of an environmental population of C. jejuni bacteriophages and their influence on the Campylobacter populations of broiler house chickens. The role of developing bacteriophage resistance was investigated as this is a possible obstacle to the use of bacteriophage therapy to reduce the numbers of campylobacters in chickens. In this broiler house succession was largely due to incursion of new genotypes rather than to de novo development of resistance.
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Farmehr, P. "Phage therapy is an important replacement for the antibiotic resistance." Pakistan Journal of Medical and Health Sciences 15, no. 5 (May 30, 2021): 1236–40. http://dx.doi.org/10.53350/pjmhs211551236.
Texte intégralRésumé :
Antibiotic resistance has become a significant and growing threat to public and environmental health. The emergence of multiple drug-resistant bacteria has prompted interest in alternatives to conventional antimicrobial. One of the possible replacement options for antibiotics is the use of bacteriophages as antimicrobial. We were forced to look for a new approach in treatment. Phage therapy is an important alternative antibiotic in the current of drug-resistance pathogens. In this way, poisoning bacteria bacteriophage bacteria infect and replicate in bacteria, in this therapy, identify the type of virus per person and can be targeted manipulation of harmful bacteria and then returned the person and invented phage therapy. We discuss the advantages and disadvantages of bacteriophages as therapeutic agents in this regard. And so describe a brief history of bacteriophages and clinical studies on their use in bacterial disease. Much hope is placed in genetic modifications of bacteriophages prevents the development of phage-resistant bacteria. Keywords: antibiotic resistance‚ bacteriophage, phage therapy
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Hervé, C., A. Coste, A. Rouault, J. M. Fraslin, and M. Gautier. "First Evidence of Lysogeny inPropionibacterium freudenreichii subsp.shermanii." Applied and Environmental Microbiology 67, no. 1 (January 1, 2001): 231–38. http://dx.doi.org/10.1128/aem.67.1.231-238.2001.
Texte intégralRésumé :
ABSTRACT Dairy propionic acid bacteria, particularly the speciesPropionibacterium freudenreichii, play a major role in the ripening of Swiss type cheese. Isometric and filamentous bacteriophages infecting P. freudenreichii have previously been isolated from cheese. In order to determine the origin of these bacteriophages, lysogeny of P. freudenreichii was determined by isometric bacteriophage type analysis. The genomic DNA of 76 strains were hybridized with the DNA of nine bacteriophages isolated from Swiss type cheeses, and the DNA of 25 strains exhibited strong hybridization. Three of these strains released bacteriophage particules following UV irradiation (254 nm) or treatment with low concentrations of mitomycin C. A prophage-cured derivative of P. freudenreichii was readily isolated and subsequently relysogenized. Lysogeny was therefore formally demonstrated in P. freudenreichii.
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Brentlinger, Karie L., Susan Hafenstein, Christopher R. Novak, Bentley A. Fane, Robert Borgon, Robert McKenna та Mavis Agbandje-McKenna. "Microviridae, a Family Divided: Isolation, Characterization, and Genome Sequence of φMH2K, a Bacteriophage of the Obligate Intracellular Parasitic Bacterium Bdellovibrio bacteriovorus". Journal of Bacteriology 184, № 4 (15 лютого 2002): 1089–94. http://dx.doi.org/10.1128/jb.184.4.1089-1094.2002.
Texte intégralRésumé :
ABSTRACT A novel single-stranded DNA phage, φMH2K, of Bdellovibrio bacteriovorus was isolated, characterized, and sequenced. This phage is a member of the Microviridae, a family typified by bacteriophage φX174. Although B. bacteriovorus and Escherichia coli are both classified as proteobacteria, φMH2K is only distantly related to φX174. Instead, φMH2K exhibits an extremely close relationship to the Microviridae of Chlamydia in both genome organization and encoded proteins. Unlike the double-stranded DNA bacteriophages, for which a wide spectrum of diversity has been observed, the single-stranded icosahedral bacteriophages appear to fall into two distinct subfamilies. These observations suggest that the mechanisms driving single-stranded DNA bacteriophage evolution are inherently different from those driving the evolution of the double-stranded bacteriophages.
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Schrader, Holly S., John O. Schrader, Jeremy J. Walker, Thomas A. Wolf, Kenneth W. Nickerson, and Tyler A. Kokjohn. "Bacteriophage infection and multiplication occur inPseudomonas aeruginosastarved for 5 years." Canadian Journal of Microbiology 43, no. 12 (December 1, 1997): 1157–63. http://dx.doi.org/10.1139/m97-164.
Texte intégralRésumé :
Bacteriophages specific for Pseudomonas aeruginosa and Escherichia coli were examined for their ability to multiply in stationary phase hosts. Four out of five bacteriophages tested, including E. coli bacteriophage T7M, were able to multiply in stationary phase hosts. The bacteriophage ACQ had a mean burst size of approximately 1000 in exponential phase P. aeruginosa hosts and 102 in starved hosts, with corresponding latent periods that increased from 65 to 210 min. The bacteriophage UT1 had a mean burst size of approximately 211 in exponential phase P. aeruginosa hosts and 11 in starved hosts, with latent periods that increased from a mean of 90 min in exponential phase hosts to 165 min in starved hosts. Bacteriophage multiplication occurred whether or not the hosts had entered stationary phase, either because the cultures had been incubated for 24 h or were starved. Significantly, bacteriophage multiplication occurred in P. aeruginosa, which had been starved for periods of 24 h, several weeks, or 5 years. Only one P. aeruginosa virus, BLB, was found to be incapable of multiplication in stationary phase hosts. These results reveal that starvation does not offer bacterial hosts refuge from bacteriophage infection and suggest that bacteriophages will be responsible for significant bacterial mortality in most natural ecosystems.Key words: bacteriophage multiplication, stationary phase, starvation.
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Rapala, Jackson, Brenda Miller, Maximiliano Garcia, Megan Dolan, Matthew Bockman, Mats Hansson, Daniel A. Russell, et al. "Genomic diversity of bacteriophages infecting Rhodobacter capsulatus and their relatedness to its gene transfer agent RcGTA." PLOS ONE 16, no. 11 (November 18, 2021): e0255262. http://dx.doi.org/10.1371/journal.pone.0255262.
Texte intégralRésumé :
The diversity of bacteriophages is likely unparalleled in the biome due to the immense variety of hosts and the multitude of viruses that infect them. Recent efforts have led to description at the genomic level of numerous bacteriophages that infect the Actinobacteria, but relatively little is known about those infecting other prokaryotic phyla, such as the purple non-sulfur photosynthetic α-proteobacterium Rhodobacter capsulatus. This species is a common inhabitant of freshwater ecosystems and has been an important model system for the study of photosynthesis. Additionally, it is notable for its utilization of a unique form of horizontal gene transfer via a bacteriophage-like element known as the gene transfer agent (RcGTA). Only three bacteriophages of R. capsulatus had been sequenced prior to this report. Isolation and characterization at the genomic level of 26 new bacteriophages infecting this host advances the understanding of bacteriophage diversity and the origins of RcGTA. These newly discovered isolates can be grouped along with three that were previously sequenced to form six clusters with four remaining as single representatives. These bacteriophages share genes with RcGTA that seem to be related to host recognition. One isolate was found to cause lysis of a marine bacterium when exposed to high-titer lysate. Although some clusters are more highly represented in the sequenced genomes, it is evident that many more bacteriophage types that infect R. capsulatus are likely to be found in the future.
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Stipniece, Liga, Dace Rezevska, Juta Kroica, and Karlis Racenis. "Effect of the Biopolymer Carrier on Staphylococcus aureus Bacteriophage Lytic Activity." Biomolecules 12, no. 12 (December 14, 2022): 1875. http://dx.doi.org/10.3390/biom12121875.
Texte intégralRésumé :
The use of implant materials is always associated with the risk of infection. Moreover, the effectiveness of antibiotics is reduced due to antibiotic-resistant pathogens. Thus, selecting the appropriate alternative antimicrobials for local delivery systems is correlated with successful infection management. We evaluated immobilization of the S. aureus specific bacteriophages in clinically recognized biopolymers, i.e., chitosan and alginate, to control the release profile of the antimicrobials. The high-titre S. aureus specific bacteriophages were prepared from commercial bacteriophage cocktails. The polymer mixtures with the propagated bacteriophages were then prepared. The stability of the S. aureus bacteriophages in the biopolymer solutions was assessed. In the case of chitosan, no plaques indicating the presence of the lytic bacteriophages were observed. The titre reduction of the S. aureus bacteriophages in the Na-alginate was below 1 log unit. Furthermore, the bacteriophages retained their lytic activity in the alginate after crosslinking with Ca2+ ions. The release of the lytic S. aureus bacteriophages from the Ca-alginate matrices in the TRIS-HCl buffer solution (pH 7.4 ± 0.2) was determined. After 72 h—0.292 ± 0.021% of bacteriophages from the Ca-alginate matrices were released. Thus, sustained release of the lytic S. aureus bacteriophages can be ensured.
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Weckmann, Andreas, and Christian Egler. "Utilization of Bacteriophages as Molecular Label." Journal of Nanoscience and Nanotechnology 8, no. 8 (August 1, 2008): 3988–89. http://dx.doi.org/10.1166/jnn.2008.18346.
Texte intégralRésumé :
We proof that nanomaterials can be successfully marked with relatively small amounts of purified bacteriophages acting as a molecular bar code label. Bacteriophages are DNA protected by a proteinous hull. The DNA fraction of the bacteriophages particle offers a nearly unlimited potential to encode information into the label. The information included in the molecular label can be read using PCR driven amplification. We show, how bacteriophage particles are easily applied to label a nanoscaled bulk material e.g., multi walled carbon nanotubes.