Search Results (156)

Phage therapy has enormous potential in combating bacterial resistance in food animals. However, its application via the oral route remains limited due to challenges associated with the gastrointestinal tract (GIT) environment and a lack of rigorous clinical trial evidence. Therefore, we systematically searched in Google Scholar, PubMed, Scopus, and Web of Science databases following PRISMA guidelines and finally identified 111 articles on oral phage therapy in food animals from where we summarized the key physiological and chemical factors of the gut environment hindering the effectiveness of oral phage therapy (OPT), examined the methods used to evaluate phage stability in the GI environment, and highlighted potential strategies to mitigate these challenges. In addition, we performed quantitative analysis to visualize in vitro pH and thermal stability patterns of phages targeting bacteria isolated from food animals and variability in buffer and incubation period across stability studies. The GIT consists of several anatomically and functionally distinct segments, where complex interactions occur among digestive enzymes, gastric acids, electrolytes, commensal microbiota, and mucosal immune components. The acidic pH of the stomach is a major barrier to successful oral phage delivery. According to our analysis of pH stability testing data from the reviewed studies, most phages targeting antimicrobial-resistant bacteria in food animals remained stable at pH 5–9 and inactivated under highly acidic (pH ≤ 2) or highly alkaline (pH ≥ 11) conditions. In addition, phages are susceptible to high temperatures (above 60 °C), digestive enzymes (e.g., pepsin, trypsin, lipases), bile salts, and host immune responses. Several in vitro laboratory techniques are available to assess phage stability under simulated GI conditions, but variations occur in the assessment protocols. Microencapsulation using alginate and chitosan has been used to protect phages from the adverse GI environment. Additionally, enteric-coated capsules, antacids, co-encapsulation with acid-neutralizing agents, consumption of alkaline water, and daily phage administration are suggested to improve phage survival and efficacy. For the successful clinical implementation of OPT in food animals, future research should focus on elucidating the molecular and physicochemical determinants of phage stability, understanding the humoral immune response to OPT, standardizing laboratory protocol for assessing phage viability, improving the scalability of encapsulation methods, and exploring other potential delivery techniques. Full article

Percutaneous cable infection of left ventricular assist device (LVAD) patients is a significant source of morbidity, often caused by biofilm-producing or multidrug-resistant bacteria. We hypothesized that bacteriophage viruses can be identified from biological samples of patients with active driveline infection. Six patients with local percutaneous lead infections were enrolled. Microbiological samples were collected from the infected wound and other skin regions. The isolated viral strains and phages from wastewater samples were then tested against the pathogen bacterial cultures in vitro. Biofilm disruption assay and genetic analysis of the strains were also performed. Bacteriophages with lytic activity could be identified from samples of two patients. One patient contained four strains showing strong efficacy against his own Staphylococcus epidermidis. Furthermore, this bacterium was susceptible to phages identified from another patient and strains from wastewater samples. Genomic analysis suggested lysogenic lifestyle of the phages. However, none of them have shown any microbiological signs of lysogeny. In conclusion, we have been able to prove in vitro lytic activity of bacteriophages originating from the same LVAD patient. We also found effective phages in biological samples of other patients and wastewater samples, suggesting that patients implanted in the same center may share bacteriophage flora. Full article

Background/Objectives: Necrotic enteritis (NE), induced by Clostridium perfringens, is responsible for significant economic losses in the poultry industry worldwide. The growing restrictions on antibiotic use have driven the search for alternative strategies for disease control. The purpose of this study is to isolate and characterize lytic phages targeting multidrug-resistant C. perfringens type G recovered from chickens with NE. Methods: C. perfringens was isolated from chickens with NE using a culture method with selective TSC agar. Bacterial identification was carried out using biochemical tests and PCR. C. perfringens isolates were toxinotyped by PCR. Antibiotic susceptibility test was performed using the agar dilution method. Bacteriophages were isolated from chicken intestine samples collected from wet markets using the double-layer agar technique. Phage isolates were characterized by host range, one-step growth, stability, and whole genome sequencing. The efficacy of phage CPP8 in controlling multidrug-resistant C. perfringens type G was evaluated in GAM broth. Results: In this study, 16 C. perfringens strains were isolated from 100 chickens suspected of NE. Among these isolates, 10 (62.5%) belonged to type G, while the remaining 6 (37.5%) were type A. A total of 11 phages capable of lysing C. perfringens type G were isolated from the chicken intestine. Among them, phage CPP8 has the widest host range, short latent period, large burst size, and high stability. Moreover, the genome of CPP8 lacked genes related to antibiotic resistance, toxins, virulence factors, or lysogeny. Treatment with CPP8 resulted in a significant reduction in viable counts of C. perfringens at 37 °C. Conclusions: Our findings highlight phage CPP8 as a promising candidate for bio-control of multidrug-resistant C. perfringens type G. Full article

Klebsiella pneumoniae, a member of the ESKAPEE group of priority pathogens, has become one of the most challenging bacterial pathogens in modern clinical practice, largely due to its multidrug resistance and the immune-evasive effect of its capsular polysaccharide (CPS). Phage-encoded depolymerases, which selectively degrade the capsular polysaccharide, have emerged as promising antimicrobial agents capable of restoring bacterial susceptibility to both immune clearance and phage infection. The fragment corresponding to the C-terminal region of a putative depolymerase of bacteriophage KlebP_144, namely DepKP144ΔC, was cloned, expressed in E. coli, and purified using immobilized metal affinity chromatography. DepKP144ΔC displays an enzymatic activity against capsular polysaccharides of 100% K1 capsular-type strains and 85% K2 capsular-type strains, including classical and hypervirulent isolates. It was demonstrated that this protein is capable of inhibiting K. pneumoniae biofilm formation, but it is unable to disrupt mature biofilms. In vivo experiments using a murine K. pneumoniae infection model further confirmed its therapeutic potential: treatment with DepKP144ΔC improved survival rate in mice infected with K2-type K. pneumoniae, indicating significant attenuation of bacterial virulence. Therefore, these results demonstrate the potential role of the C-terminal domain of the bacteriophage KP144 tail-fiber protein in phage entry and show that its carbohydrate-recognition motifs possess enzymatic activity against the Klebsiella capsular polysaccharides. Full article

Shigellosis remains a significant global cause of infectious colitis, increasingly complicated by multidrug-resistant strains and the microbiota-disrupting effects of broad-spectrum antibiotics. Although conventional antimicrobial therapy can reduce symptom duration and bacterial shedding, it also contributes to gut dysbiosis, loss of colonization resistance, and further selection for antimicrobial resistance. These challenges have renewed interest in precision antimicrobial strategies, particularly bacteriophage therapy, which provides strain-level specificity and preserves the gut microbiota. This narrative review evaluates the biological rationale, preclinical and early clinical evidence, safety considerations, and translational challenges associated with bacteriophage therapy targeting Shigella spp. The historical development and mechanistic basis of phage therapy are summarized, with emphasis on the advantages of obligately lytic phages, receptor-specific targeting, self-amplification at infection sites, and activity against both planktonic and biofilm-associated bacteria. Recent microbiota research indicates that shigellosis is closely associated with early and persistent disruption of gut ecology, including depletion of short-chain fatty acids-producing taxa and reduced microbial resilience. Phage-based approaches may reduce pathogen burden while preserving beneficial microbial communities. Evidence from in vitro systems, animal models, human intestinal organoids, and a Phase 1 clinical trial demonstrates targeted efficacy and favorable safety profiles for Shigella-specific phages and phage cocktails. Major barriers to clinical adoption include immune interactions, phage resistance dynamics, genomic safety screening, regulatory classification, and the need for standardized susceptibility testing. Future directions emphasize the development of personalized phage therapy platforms that integrate rapid diagnostics, phage libraries, metagenomics, and artificial intelligence-assisted matching to enable scalable, precision treatment. Full article

Seafood products are highly perishable and particularly susceptible to contamination by pathogenic and spoilage microorganisms, including Listeria monocytogenes, Vibrio spp., Salmonella spp., and Escherichia coli. Conventional control strategies in seafood processing and storage largely rely on chemical preservatives and thermal treatments, which may negatively affect sensory quality and increasingly conflict with consumer demand for minimally processed, “clean-label” foods. In this context, bacteriophages, viruses that specifically infect and lyse bacterial hosts, have emerged as natural, targeted, and environmentally sustainable biocontrol agents for food safety applications. This review provides a comprehensive assessment of bacteriophage applications in seafood processing and storage, with particular emphasis on their mechanisms of action, host specificity, and ability to selectively reduce pathogenic bacteria without compromising nutritional or sensory attributes. Recent advances in phage-based technologies, including phage cocktails, immobilized phage systems, and genetically engineered phages, are discussed in relation to their efficacy against major seafood-associated pathogens under both laboratory and industrial conditions. Key challenges limiting large-scale implementation such as phage resistance development, regulatory considerations, stability during processing and storage, and consumer perception are critically evaluated. In addition, the review highlights emerging evidence on the synergistic use of bacteriophages with complementary preservation strategies, including natural antimicrobials and innovative packaging systems. Overall, this review underscores the potential of bacteriophage-based interventions as practical and sustainable tools to enhance seafood safety, extend shelf life, and support modern seafood processing practices aligned with evolving regulatory and consumer expectations. Full article

Being first applied for the treatment of infectious diseases of the gut at the start of the 20th century, bacteriophages are again now considered as alternative antimicrobial tools for targeting antibiotic-resistant enterobacteria. Here, we report the new bacteriophage Escherichia phage KEC4 isolated from the Kukshum River (Chuvash Republic, Russia), lysing Escherichia coli and belonging to the Septuagintavirus genus. The genome consists of 145,125 bp with a GC content of 41.3% and contains 6 tRNA and 303 protein-coding sequences. Among them, only 72 encode proteins with known functions, while no proteins potentially associated with lysogeny can be identified. The bacteriophage forms round and pure plaques 0.3–1 mm in diameter and is capable of lysing 14 of 31 E. coli clinical isolates with multiple resistance patterns. Furthermore, in the presence of KEC4, the MICs of meropenem and kanamycin decreased 16-fold in the reference strain. In clinical multidrug-resistant isolates, a 16-fold decrease in the MIC was observed for aminoglycosides (amikacin and gentamicin) for the isolate NKC1, and an eight-fold drop in the MIC of ceftriaxone was observed for isolate 167, with no increase in the efficiency of aminoglycosides. Finally, a four-fold increase in the efficiency of both azithromycin and gentamicin was detected in isolate 5767. Taken together, these data characterize the new Escherichia phage KEC4 as a promising tool for the treatment of infections associated with Escherichia coli, while a preliminary assessment of both the isolate specificity of the phage and an antimicrobial susceptibility test would be required for successful elimination of the pathogen. Full article

Background/Objectives: The gut microbiota is increasingly recognized as a key determinant of human health, playing a vital role in metabolism, immunity, and disease susceptibility. Dysbiosis, or microbial imbalance, is associated with gastrointestinal disorders such as irritable bowel syndrome (IBS), inflammatory bowel disease (IBD), and Clostridioides difficile infection (CDI), as well as extraintestinal conditions, including obesity, cardiovascular disease, and neuropsychiatric disorders. This review aims to provide an updated overview of emerging therapeutic strategies to modulate the gut microbiota to restore eubiosis and improve health outcomes. Methods: A narrative review of recent literature was conducted, focusing on preclinical and clinical studies investigating microbiota-targeted therapies. The review primarily covers innovative interventional approaches, including fecal microbiota transplantation (FMT), bacterial consortium transplantation (BCT), bacteriophage therapy and outer membrane vesicles (OMVs). Results: Evidence supports the role of probiotics, prebiotics, and synbiotics in remodeling microbial communities and improving host health, although their effects may be strain- and context-dependent. FMT has demonstrated high efficacy in the treatment of recurrent Clostridium difficile infections and is being studied for IBD, IBS and extraintestinal diseases, following the recent Food and Drug Administration approval of the first commercial FMT products. BCT offers a standardized alternative to donor-derived material, with early clinical successes such as FDA-approved SER-109. Phage therapy and OMVs represent promising frontiers, offering targeted microbial modulation and interactions with the immune system, although clinical data remain limited. Conclusions: Emerging gut microbiota modulation strategies offer new perspectives for precision medicine and could transform the prevention and treatment of many diseases, but further studies are needed to ensure their safety, standardization, and clinical application. Full article

Agrobacterium tumefaciens, a destructive pathogen causing crown gall disease, results in substantial agricultural losses. Traditional chemical and existing biocontrol methods are limited by environmental pollution, pesticide resistance, and low efficacy, while bacteriophages emerge as a promising alternative due to their high host specificity, environmental compatibility, and low resistance risk. In this study, we isolated and characterized a lytic phage (PAT-A) targeting A. tumefaciens, evaluating its biological traits, genomic features, and biocontrol potential. The host strain A. tumefaciens CL-1 was isolated from cherry crown gall tissue and identified by 16S rDNA sequencing. Phage PAT-A was recovered from orchard soil via the double-layer agar method, showing a tadpole-shaped morphology (60 nm head diameter, 30 nm tail length) under transmission electron microscopy (TEM). Nucleic acid analysis confirmed a double-stranded DNA genome, susceptible to DNase I but resistant to RNase A and Mung Bean Nuclease. PAT-A exhibited an optimal MOI of 0.01, tolerated wide pH and temperature ranges, but was sensitive to UV (titer declined after 15 min of irradiation) and chloroform (8% survival at a 5% concentration). Whole-genome sequencing revealed a 44,828 bp genome with a compact structure, and phylogenetic/collinearity analyses placed it in the Atuphduvirus genus (Autographiviridae). Biocontrol experiments on tobacco plants demonstrated that PAT-A significantly reduced crown gall incidence. Specifically, simultaneous inoculation of PAT-A and A. tumefaciens CL-1 resulted in the lowest tumor incidence (12.0%), while pre-inoculation of PAT-A 2 days before pathogen exposure achieved an incidence rate of 33.3%. In conclusion, PAT-A is a novel strictly lytic phage with favorable biological properties and potent biocontrol efficacy against A. tumefaciens, enriching phage resources for crown gall management and supporting phage-based agricultural biocontrol strategies. Full article

Phages play a role in shaping ecosystems by controlling host abundance via cell lysis, driving host evolution via horizontal gene transfer, and promoting nutrient cycling. The genus Bradyrhizobium includes bacteria able to symbiotically nodulate the roots of soybean (Glycine max), providing the plant with a direct source of biologically fixed nitrogen. Optimizing this symbiosis can minimize the use of nitrogen fertilizers and make soybean production more sustainable. Phages targeting Bradyrhizobium may modify their hosts’ genotype, alter phenotypic traits such as symbiotic effectiveness, and mediate competition among strains for nodulation sites. Sixteen phages were isolated against B. diazoefficiens strain USDA110 and B. elkanii strains USDA94 and USDA31. Comparative analyses revealed host species-dependent diversity in morphology, host range, and genome composition, leading to the identification of three previously undescribed phage species. Remarkably, all B. elkanii phages shared a siphophage morphology and formed a single species with >97% nucleotide identity, even when isolated from farms separated by up to ~70 km, suggesting genomic stability across geographic scales. In contrast, phages isolated against B. diazoefficiens had a podophage-like morphology, exhibited greater genetic diversity, and divided into two distinct species. Although no phages were recovered against the B. japonicum strains or native Delaware Bradyrhizobium isolates tested, some Delaware Bradyrhizobium isolates showed susceptibility in a host range assay. The phage genomes demonstrated features predicting phenotypes. The phage terminase genes predicted headful packaging which promotes generalized transduction. The B. elkanii phages all carried tmRNA genes capable of rescuing stalled ribosomes, and all but one of the phages isolated against the two host species carried DNA polymerase A indicating greater phage control of genome replication. State-of-the-art structural annotation of a hypothetical gene shared by the B. diazoefficiens phages, having a mean amino acid identity of ~25% and similarity of ~35%, predicted a putative tail fiber function. Together this work expands the limited knowledge available on soybean Bradyrhizobium phage ecology and genomics. Full article

Acinetobacter baumannii is a critical public health threat, particularly with the rise in multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains that limit treatment options. Phage therapy, which uses bacteriophages to target bacteria, offers a promising alternative. We isolated an XDR strain (Ab125) from a burn wound infection and screened 34 phages, identifying vB_AbaM_3098 as the only effective candidate. However, resistance rapidly emerged, producing a derivative strain (Ab139). Interestingly, Ab139, though resistant to vB_AbaM_3098, became susceptible to six previously inactive phages. While various potential determinants were identified through comparative genomics and proteomics, the mechanism causing phage resistance to vB_AbaM_3098 and simultaneous susceptibility to other phages remains to be elucidated. Among the six new candidates, vB_AbaM_3014 was the most promising. While each phage alone allowed bacterial regrowth, combining vB_AbaM_3098 and vB_AbaM_3014 completely suppressed Ab125 growth. In a Galleria mellonella infection model, this cocktail achieved 90% survival after five days compared to 0% in untreated controls. Notably, the cocktail combined one phage with modest activity and another inactive phage against the parental strain; together, they produced strong bactericidal effects. These findings highlight both the complexity of phage cocktail design and their promise as adjunct therapies against drug-resistant A. baumannii. Full article

The rapid emergence of antibiotic-resistant bacteria requires solutions that extend beyond conventional antibiotics. Bacteriophages (phages) provide targeted antibacterial action but face two key limitations: (1) their narrow natural host ranges and (2) the rapid emergence of evolved bacterial resistance. This review focuses specifically on evolved resistance and highlights two complementary strategies to overcome it by using phage-adaptive evolution and manipulating bacterial fitness trade-offs. Adaptive evolution accelerates phage/bacteria coevolution under host-mediated and environmental selective pressures such as receptor variability, bacterial resistance mutations, and nutrient limitations, resulting in phages with broader host targeting within resistant populations and enhanced lytic activity. Simultaneously, bacterial resistance to phages often leads to fitness costs, including restored antibiotic susceptibility or reduced virulence. These strategies support the rational design of phage/antibiotic combinations that suppress resistance and enhance therapeutic efficacy. In this review, we clarify the distinction between intrinsic host range limitations and evolved resistance, focusing on how adaptive strategies can specifically counter the latter. We discuss the underlying mechanisms, practical applications, and significance of this approach in clinical, agricultural, and environmental areas. Full article

Background/Objectives: This report documents the first confirmed case in Romania of fatal pneumonia and septicemia in a domestic rabbit caused by multidrug-resistant Escherichia coli, highlighting both its pathogenic potential and One Health implications. Case Study: An 8-month-old male German Giant Spotted rabbit raised on a rural farm under poor husbandry conditions developed acute respiratory distress and died within 48 h. Post-mortem examination revealed severe pulmonary congestion, tracheal inflammation, serofibrinous pericarditis, and systemic vascular lesions. Bacteriological analysis confirmed E. coli from lung, trachea, and bone marrow samples. The isolate demonstrated strong Congo red binding, was confirmed by MALDI-TOF mass spectrometry, and showed resistance to beta-lactams, fluoroquinolones, tetracyclines, sulfonamides, macrolides, and phenicols, remaining susceptible only to aminoglycosides. PCR screening identified virulence genes (fimH, papC, iutA, ompA) linked to adhesion, immune evasion, and iron acquisition, with potential for horizontal gene transfer. Conclusions: This first documented case in Romania emphasizes the clinical threat posed by multidrug-resistant E. coli in rabbits and the importance of early diagnosis, improved biosecurity, and responsible antimicrobial use. The zoonotic and environmental risks in backyard farming underscore the urgent need for integrated surveillance. Alternative control strategies, including phage therapy and probiotics, should be explored to reduce reliance on conventional antibiotics. Full article

Lytic bacteriophages, viruses that attack and kill bacteria cells, can be used in food as biocontrol agents to prevent the growth of pathogenic bacteria. Meat is highly susceptible to bacterial growth, including pathogenic species, the control of which is crucial. Antibiotic use by breeders has resulted in bacterial resistance, which remains a huge problem; bacteriophages have emerged as an interesting alternative. In the literature, the influence of bacteriophages on common foodborne pathogens, such as Salmonella sp., Listeria monocytogenes, Campylobacter jejuni, Yersinia enterocolitica, Escherichia coli, and Shigella sp., has been described. Some phage preparations can show synergistic effects when used with other antimicrobial agents. However, data on the use of bacteriophages to inhibit the growth of meat spoilage bacteria are limited. Bacteriophages can also synthesize endolysins, which possess antimicrobial properties. Contrary to bacteriophages, which are active against only a narrow range of microorganisms (usually one bacterial species), endolysins show a broad spectrum of activity. Full article

Antimicrobial resistance (AMR) is a growing global health emergency that threatens the effectiveness of modern medicine, exacerbating healthcare costs, morbidity, and mortality, particularly in low- and middle-income countries (LMICs). Traditional approaches to antimicrobial development and stewardship have proven inadequate in curbing the rapid emergence and spread of resistant pathogens. This review explores cutting-edge biotechnological innovations as sustainable, precision-based solutions to combat AMR and promote global health equity. A comprehensive narrative review was conducted using literature published between 2018 and 2023 from PubMed, ScienceDirect, and Web of Science. Peer-reviewed studies focusing on novel antimicrobial strategies were thematically analyzed, with attention to efficacy, feasibility, and translational readiness. Key innovations identified include nanotechnology-enhanced antimicrobial delivery, bacteriophage therapy, CRISPR-Cas gene editing, immunotherapy, and personalized medicine. These strategies demonstrated substantial in vitro and in vivo efficacy, such as >90% MRSA biofilm reduction via silver nanoparticles and 95% carbapenem susceptibility restoration in E. coli using CRISPR-Cas9. When integrated with machine learning and rapid diagnostics, these approaches enable precision-targeted therapies and data-informed stewardship, offering scalable solutions adaptable to diverse healthcare systems. Antimicrobial resistance demands urgent, equitable innovation. Integrating biotechnologies like CRISPR, phage therapy, and nanomedicine with data-driven tools offers promising solutions. To ensure real-world impact, we recommend establishing regionally tailored translational research platforms and public–private partnerships as the most effective strategy to scale innovations and strengthen AMR response in low-resource settings. Full article