Poster preparation and presentation information
Thank you for considering presenting your work as a poster at this conference. Below are the key details and submission guidelines.
Deadlines
- Poster abstracts (as MS Word) must be submitted by 15th August.
- Digital posters (as PDF) and flash-talk videos must be submitted by 20th August.
Poster preparation & format
Poster size
Digital-only presenters
- Save your poster in A1 or A0, landscape or portrait format.
- Page size is flexible if presenting only digitally.
In-person presenters
- Print your poster in A1 portrait format only
- Larger or landscape posters may not be displayed due to space constraints
File naming
For submission, name your digital poster files as follows:
- <your surname>-Phg26-Poster.
- Example: for David Jones, name your file as Jones-Phg26-Poster.
- Do not use generic names such as: Oxford-poster, phages2026, Oxford-phage-poster.
Digital poster submission
All poster presenters, whether attending virtually or in person, are required to submit a digital version (as PDF) of their poster via the designated upload link. Posters will be made accessible to all conference participants via the secure ‘Download PHG26 Documents’ page, ensuring visibility across both virtual and in-person audiences.
- Submit your final PDF poster (<5MB) via the designated upload link
- Do not send posters or abstracts by email
- Ensure your submission is final—once published, it cannot be replaced
- Late submissions may not be included in the programme
Poster presentation
Presentation timing
Presenting digitally only
- Currently, there is no scheduled time for presenting digital posters. Instead, virtual attendees will be able to interact with poster presenters via the Zoom chatbox during the conference.
- A specific poster presentation session may be announced later.
Presenting in-person
- Bring a printed A1 portrait poster for display
- Larger or landscape posters may not be displayed due to space constraints
- You are responsible for printing and transporting your poster
- You may be assigned a specific day and time for display
Presentation via a flash-talk video
To maximise visibility, exposure and engagement, we encourage all poster presenters, whether presenting digitally or in-person, to submit a short video (max 5 minutes) introducing their work. Videos will be featured on the LPMHealthcare YouTube channel.
Instructions
- Download the official opening slide (PhgOx26 opening slide) and use it as the first slide of your presentation (see example: https://youtu.be/XatqenCd_IU?si=Yu1PooCD4JmSLAiz).
- Record your presentation using Zoom or any preferred platform. Keep it under 5 minutes.
- Save your video in a YouTube-compatible format (e.g., MP4)
- Send your video via a file transfer service such as MailBigFile or WeTransfer to: PhageOxford@gmail.com
Any further information about the poster presentations will be available in the future on this page.
Before uploading your poster, you must make sure that you follow ALL of the instructions above!
Accepted posters
(Unedited: V = Virtual-only posters; presenters are shown in Bold)
Accepted poster abstracts will be displayed below. If your abstract has been accepted for presentation but it does not appear in the list below, please let us know as soon as possible by emailing PhageOxford@gmail.com.
Engineering and Functional Characterisation of Novel Bacteriophage Endolysins Targeting Staphylococcus aureus
Sami Asiri, John E Pearl, Edouard Galyov
Becky Mayer Centre for Phage Research, Division of Microbiology and Infection, University of Leicester, Leicester, United Kingdom
Antimicrobial resistance in Staphylococcus aureus, particularly methicillin-resistant S. aureus (MRSA), has increased the need for alternative antimicrobial strategies. Bacteriophage-derived endolysins are peptidoglycan hydrolases that rapidly lyse Gram-positive bacteria and represent promising protein therapeutics. In this study, ten S. aureus bacteriophages were isolated, and their genomes were sequenced, assembled and taxonomically classified. Four endolysins from these phages were selected for further characterization. Three variants of each endolysin, comprising a full-length protein and two C-terminal truncations, were engineered and cloned as His₆-SUMO fusion proteins. Recombinant protein expression conditions were optimized. All twelve constructs were successfully expressed in the soluble fraction and screened for antibacterial activity against three MRSA and three methicillin-susceptible S. aureus (MSSA) isolates. Of the twelve constructs, only the full-length E1 endolysin demonstrated reproducible lytic activity against all six strains tested. In addition, the soluble E1 lysate exhibited a broader antibacterial spectrum than its parental bacteriophage. The remaining constructs showed no detectable activity as soluble His₆-SUMO fusion proteins. Ongoing work will purify the recombinant proteins, remove the His₆-SUMO fusion tag and reassess antibacterial activity to determine whether the fusion partner influences endolysin function.
Leading the future of Phage Therapy: Targeting Microbiome in Gastrointestinal Cancer
Birhanu Ayelign1,2,3, Shoukat Afshar-Sterle1,2, Ryan O’Keefe1,2, Mwila Kabwe4, Annalisa Carli1, 2, Bushra Amin5, Joseph Tucci4, Michael Buchert1,2
1Olivia Newton-John Cancer Research Institute, Melbourne, Victoria, Australia
2School of Cancer Medicine, La Trobe University, Victoria, Australia
3Department of Immunology and Molecular Biology, School of Biomedical and Laboratory Science, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
4Department of Pharmacy and Biomedical Sciences, La Trobe Institute for Molecular Science, La Trobe University, Victoria, Australia
5Mass Spectrometry research and infrastructure, la Trobe university, Australia
The study of the cancer microbiota is an emerging research area that has gained attention through discoveries of the tumour-associated bacterial species that can be tumourigenic. Fusobacterium nucleatum (F. nucleatum) is a recognised cancer-associated oral microbiome linked to tumour growth, immune suppression, and resistance to therapy. Clinical use of antibiotics targeting F. nucleatum has failed, leading to worse patient outcomes. Thus, there remains a significant gap in understanding tumour-promoting mechanisms and efficiently targeting the bacterium. We aimed to address a critical unmet need by understanding how tumour-associated bacteria contribute to cancer progression and discovering a world-first novel FNU1 bacteriophage capable of eliminating these bacteria. Cancer cells were infected with F. nucleatum and subsequently treated with FNU1 bacteriophage. Functional assays demonstrated that F. nucleatum infection significantly increased cellular migration, proliferation and viability in infected cells. While FNU1 bacteriophage treatment blocks F. nucleatum-induced cancer cell proliferation and migration. Flow cytometry was used to quantify the expression of major histocompatibility complex class I (MHC-I). Infected cells showed significant downregulation of MHC-I expression, as confirmed by Western blot analysis, which revealed reduced levels of MHC-I and associated chaperone proteins involved in MHC-I maturation and translocation. Treatment with FNU1 reversed these changes, restoring MHC-I expression and chaperone protein levels. Label-free quantitative proteomics employing high-resolution LC–MS/MS identified distinct infection-associated proteomic signatures enriched in pro-tumorigenic pathways. Differential expression analysis demonstrated that these alterations were significantly reduced following bacteriophage treatment, indicating extensive reprogramming of infection-driven cellular pathways.
Machine Learning to Enhance Phage Therapeutic Potential
Kenneth Cox, Austen Terwilliger, Keiko Salazar, Alexander Cervantes, Anthony W Maresso
TAILOR Labs / Maresso Lab, Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, USA
Bacteriophage therapy is a promising option for antibiotic-resistant infections, yet outcomes remain inconsistent. In the largest personalized phage therapy series to date (100 consecutive cases across 36 hospitals in 12 countries), 23% of infections showed no clinical improvement and 39% were not eradicated, underscoring the need for better ways to select phages likely to succeed in patients. Recent machine learning (ML) methods can predict phage-host interactions from genomic information alone, using genome-derived features or protein language model embeddings. However, these models are almost universally trained on interactions measured in rich laboratory media, such as plaque and spot assays on LB. Growing evidence shows that the physiological setting reshapes phage activity: human serum can inhibit phages in a concentration-dependent manner, divalent cations can enhance phage killing of bacteria in blood by orders of magnitude, and killing differs between urine and blood. Selecting phages based on laboratory media may therefore poorly reflect performance in the clinical environment. We are developing an ML framework to learn which phage genomic features enable productive infection in clinically relevant media. First, we select phages with broad E. coli host range, to avoid class imbalance in the dataset. Second, we train interpretable models on genomic features (k-mer frequencies, protein clusters) and embedding-based models on protein language model representations, comparing random forest and XGBoost architectures. Finally, we predict the phages most likely to infect hosts under clinical conditions. By making phage selection media-aware, this work aims to improve phage selection and, ultimately, the treatment of difficult bacterial infections.
How Mycobacterial Physiological State Influences Mycobacteriophage Infectivity
Stephen Emencheta1, Pranabashis Haldar2, Galina Mukamolova1, Natalie Garton1
¹Division of Microbiology and Infection, University of Leicester, Leicester, United Kingdom
2Division of Respiratory Sciences, School of Medical Sciences, University of Leicester, Leicester, Leicestershire, UK
With the rising incidence of mycobacterial diseases and the challenges of their treatment, mycobacteriophages are becoming an attractive alternative; however, many barriers remain, and few have been tested against Mycobacterium tuberculosis. There is also a lack of understanding of whether mycobacteriophages can infect mycobacteria in different phenotypic states relevant to infection. This study aims to evaluate the infectivity of mycobacteriophages (D29 and TM4) against Mycobacterium species, including Mycobacterium bovis (BCG) strains (Glaxo and Pasteur) and M. tuberculosis mc26030, under different physiological conditions, including in the presence and absence of Tween 80, during the exponential and stationary growth phases of mycobacteria, and under varying oxygen availability. Tween negatively impacted the infectivity of D29 and TM4. Across the conditions (growth phases and oxygen tensions) tested, both infected best during the exponential phases of BCG and M. tuberculosis mc26030; however, TM4 infected more robustly and more effectively against non-growing and stressed mycobacteria than D29. These findings lay the foundation for developing and prioritising choice mycobacteriophage(s) and show that physiologically relevant models are essential for evaluating therapeutic mycobacteriophages.
Phenotypic and Genotypic Characterisation of Novel Coliphages with Therapeutic Potential Targeting Multi-Drug Resistant E. coli Clinical Isolates
Shauna K Hurley, Peter Myintzaw, Aidan Coffey, Michael Callanan and Laura M O’Connell
Munster Technological University, Bishopstown, Cork, T12 P928, Ireland
Given the concerning rise of antibiotic resistance, alternative therapeutic strategies are required for treating enteric pathogens such as Escherichia coli. One such strategy is the application of lytic (bacterio)phages or their components. As routine application of phage-based therapies is typically limited by narrow host ranges and variable stability, isolation of novel lytic phages remains an important feature of this research field. This study examined the therapeutic potential of 4 novel coliphages that were recently isolated from water sources in Cork, Ireland. Phenotypic analysis revealed that all phages remained functionally stable between pH 3 and 11 and up to 70°C and in silico analysis revealed that the phages are closely related to T4-like coliphages. Pharokka-based genomic analysis confirmed their strictly lytic lifestyle (between 110-168 kbp, lacks integrases) and the absence of toxin-encoding genes, which are considered desirable characteristics of therapeutic phages. The novel coliphages were subsequently tested in vitro to determine their host range against a panel of 20 clinical E. coli isolates obtained from the Bons Secours Hospital, Cork. The E. coli isolates were examined for their susceptibility to antibiotics. Isolates were found to be most resistant to beta-lactams and showed resistance to 14 of 16 antibiotics tested. However, the novel coliphages V2, V3, V7 and KB4 lysed 55%, 60%, 50%, and 40% of 20 E. coli isolates, respectively, with only two isolates resistant to all phages. Overall, the results demonstrate the therapeutic potential of these phages and support further experimental validation. Future work will focus on cloning and characterising the phage endolysins as potential antibacterial agents independent of the whole phage particles, as well as their targeted delivery to the gut.
Characterisation of Bacillus anthracis Bacteriophages
Catriona Matthews1,2, Ertelt Moritz3, Georgie Metters1, Chris Jenkins1, Peter Braun3, Izzy Norville1, Joanne L. Fothergill4, Viviana Manzulli5, Domenico Galante5, Les Baillie2, Philip Ireland1
1Defence Science and Technology Laboratory (Dstl), Porton Down, Salisbury, UK
2Cardiff School of Pharmacy and Pharmaceutical Sciences, King Edward VII Avenue, Cardiff University, Cardiff CF10 3NB, UK
3Fraunhofer Institute for Translational Medicine and Pharmacology (ITMP), Immunology, Infection and Pandemic Research, 80799 Munich, Germany
4Department of Clinical Infection, Microbiology and Immunology, University of Liverpool, Liverpool, UK
5Istituto Zooprofilattico Sperimentale of Puglia and Basilicata, Anthrax Reference Institute of Italy,71121 Foggia, Italy
Bacillus anthracis, a Gram-positive, spore-forming bacterium, is the causative agent of anthrax, a zoonotic disease found worldwide with significant implications for both animal and human health. The disease primarily affects livestock and wild animals but can also infect humans, with the infection route influencing disease progression and severity. While tools exist for B. anthracis detection, treatment and decontamination, bacteriophages present a promising alternative and complement to these methods. Their high specificity, limited disruption to existing microbial flora, ability to replicate during treatment and environmental sustainability make them an attractive option for enhancing existing strategies. This project aims to characterise and develop bacteriophages as novel medical countermeasures against B. anthracis. A collection of 15 B. anthracis bacteriophages was assembled from soil samples sourced globally. This includes three Basilisk-like phages and one Gamma-like phage from Wales, three previously characterised phages from Poland, and eight novel phages isolated from regions of Bangladesh associated with anthrax outbreaks in humans and animals during 2010-2011. Whole genome sequencing revealed significant diversity within the collection, including representatives of the families Myoviridae, Tectiviradae and Siphoviridae. Notably, two phages, 3Ban and 6Ban, exhibit a high degree of novelty, with no close relatives identified. Ongoing work includes host range testing and investigation of phage resistance. So far, this has revealed broad susceptibility to phages LC1H911 and 3B6, and clusters of closely related phage resistant strains have been identified. Phage resistant mutants arising following phage exposure were isolated and sequenced providing an early indication of the surface properties potentially required for host cell interaction. © Crown Copyright 2026, Dstl. This material is licensed under the terms of the Open Government Licence.
Gene engineering of a capsid protein as a first step in creating bionanoparticles (V)
Jakub Mazur, Agnieszka Żylicz-Stachula, Joanna Żebrowska, Piotr Skowron
University of Gdańsk, Faculty of Chemistry, Department of Molecular Biotechnology, Wita Stwosza 63, 80-308, Gdańsk, Poland
Bacteriophages are ubiquitous in nature and represent promising sources ofnew protein for the development of novel bionanotechnological platforms. Increasing attention has been focused on phage capsid proteins due to their ability to self-organise into multimeric structures, such as portal proteins. Portal proteins form a characteristic ring-like structure, which phage DNA can pass through during infection. Importantly, such structures do not contain genetic material, they could be used e.g. as a scaffolds for protein delivery system. Their functionality can be expanded using genetic engineering. In this study, we employed SpyTag/SpyCatcher system, a pair of protein tags that, can connect to each other by creating a spontaneous covalent bond between the tags. Fusing SpyTag on one protein and SpyCatcher on second allows for connecting such recombinant proteins together. The aim of this study was to design and develop new generation bionanoparticles platform based on: (i) Portal protein derived from thermophilic bacteriophage TP-84, fused to a SpyTag motif (ii) Superfolder GFP, used as a reporter protein, fused to SpyCatcher. This approach allows for portal protein multimeric structure to couple with recombinant sfGFP. Both recombinant proteins were overproduced in E. coli and then purified. Protein-protein interaction tests were evaluated using immunodetection techniques. This study represents a first step in creating new generation bionanoparticles based on thermophilic bacteriophage capsid proteins. Future studies will focus on replacing sfGFP with biologically active peptides/proteins fused with SpyCatcher motif, expanding the potencial applications in biotechnology and biomedicine.
Characterization of Staphylococcus aureus phage sv_blaze3 isolated from a secondary hospital sewage sample in the Philippines
Christian Marie Perez1,2, Tracey Antaeus Gutierrez1,3, Mark Dominic Casais1,2,4, Javier Ignatio Neri1,2, Erica Lapuz2, Rosaneth Teh2, Reuel Bennett1,3, and Donna May Papa1,2,3
1Research Center for the Natural and Applied Sciences, University of Santo Tomas, España, Manila, Philippines
2Bacteriophage Ecology, Aquaculture, Therapy and Systematics (BEATS) Research Group, University of Santo Tomas, Manila, Philippines
3Department of Biological Sciences, College of Science, University of Santo Tomas, España, Manila, Philippines
4Science Education Institute, Department of Science and Technology, Bicutan, Taguig, Philippines
A Staphylococcal phage, sv_blaze3, was isolated in a secondary hospital in Rizal, Philippines using ATCC BAA-44 as the isolation host. Sv_blaze3 was described to have long contractile tails and an isometric capsid. The capsid diameter, tail length, tail width, baseplate length, and width measure 85 nm, 101.61 nm, 21.09 nm, 43.78 nm, and 19.36 nm, respectively. It was characterized to have a broad host range and a good stability in varying levels of pH and temperature. It also has an MOI of 10 and latent period of 10 min. Based on its genomic analysis, sv_blaze3 has a linear genome encoded for 158 hypothetical, 83 functionally-annotated proteins, and 4 transfer RNAs (tRNAs). It has a taxonomic lineage of Genus Kayvirus, Subfamily Twortvirinae, Family Herelleviridae, and a 95% similarity with Staphylococcus phage Stab21, suggesting that sv_blaze3 is a new species under Genus Kayvirus. Functional analyses also revealed the presence of endolysin. Overall, the results suggest that sv_blaze3 has an antibiotic potential against multi-drug resistant S. aureus strains.
Comparative Evaluation of Phage Cocktail-, Vancomycin-, and Hybrid-Loaded Hydrogels in treating Staphylococcus aureus Burn Wound Infection in Murine Model
Jhasmin Mae I. Cabana1,2,3, Nga Sze Lin1,2,3, Sophia Therese G. Santos1,2,3, Carlos Jiean M. Sevidal1,2,3, Erica M. Lapuz2,3, Gale Bernice N. Fungo2,3, Javier I. Neri2,3, Christian Marie DC. Perez2,3, Rosaneth E. Teh2,3, Mark Dominic A. Casais2,3,4, Donna May DC. Papa1,2,3
1Department of Biological Sciences, College of Science, University of Santo Tomas, Manila, Philippines
2Bacteriophage Ecology, Aquaculture, Therapy and Systematics (BEATS) Research Group, University of Santo Tomas, Manila, Philippines
3Research Center for the Natural and Applied Sciences, University of Santo Tomas, España, Manila, Philippines
4Science Education Institute, Department of Science and Technology, Bicutan, Taguig, Philippines
Antimicrobial resistance in Staphylococcus aureus poses critical challenges in managing burn wound infections. This study investigated a phage cocktail-loaded hydrogel as a topical therapy against S. aureus-induced burn wound infections in BALB/c murine models. Specifically, this study phenotypically characterized S. aureus bacteriophages sv_blaze12, sv_blaze13, and sv_blaze14 in terms of morphology, host range and stability; and evaluated their in vitro and in vivo efficacy when applied topically via hydrogel. Morphologically, all three phages were identified to be siphoviruses, with icosahedral capsids (~74–84 nm) and long, flexible, non-contractile tails (~209–241 nm). They were also observed to be stable at 30–40 °C and neutral pH, with sv_blaze13 and sv_blaze14 maintaining stability at pH 5 and pH 9. All phages showed susceptibility against S. aureus strains, but sv_blaze12 was noted to be the most lytic phage. These three phages were used in phage cocktail formulation. The results suggest that the phage cocktail was more effective compared to monophage treatments. Thus, the cocktail was used and loaded into a sodium alginate-carboxymethylcellulose (SA-CMC) hydrogel and combined with vancomycin to assess phage-antibiotic synergy. The swelling index of the SA-CMC hydrogel peaked at day 6 and exhibited favorable biodegradation kinetics by day 14. In vitro, the hybrid-loaded hydrogel achieved the lowest bacterial count at 8 hours and produced the largest zone of inhibition in disk diffusion. In vivo, the hybrid treatment group achieved complete bacterial clearance by day 10, sustained through day 15, alongside the highest wound closure rate. These findings collectively suggest that phage-antibiotic combination therapy delivered as an SA-CMC hydrogel dressing is a potential alternative strategy for managing S. aureus burn wound infections.
Breaking or Building Biofilms? The complex role of a lytic phage in Pseudomonas aeruginosa
Johanna Pukall1, Hannah Sadrich1, Rabea Schlüter2, Susanne Sievers1
1Department of Microbial Physiology and Molecular Biology, University of Greifswald, Germany
2Imaging Center of the Department of Biology, University of Greifswald, Germany
Bacterial biofilms are highly complex and exhibit increased virulence due to their profound resistance to antibiotics. Bacteriophages can combat these structures by producing biofilm-degrading enzymes or by infecting persistent cells. In this study, we isolated a novel bacteriophage, vB_PaeP_HGW_003, from wastewater in Greifswald, Germany, targeting Pseudomonas aeruginosa. Sequencing and microscopic analyses revealed a strictly lytic phage belonging to the Autographiviridae with podovirus morphology. We characterized its impact on established monoculture biofilms and, to investigate the role of bacterial communication, we also tested a deletion mutant lacking two major quorum-sensing (QS) systems. Scanning electron microscopy (SEM) of phage-infected biofilms revealed severe disruption in the wild-type strain. Surprisingly, the QS-deficient mutant maintained a relatively intact biofilm structure under phage-mediated stress. Proteomic analyses revealed distinct expression changes, including the induction of the biofilm-associated protein PslJ. These findings suggest a unique survival strategy, and future studies aim to unravel the molecular mechanisms behind the competitive advantage of QS deficiency in the emergent pathogen P. aeruginosa.
Efficacy of an experimental bacteriophage preparation to support disinfection and improve the welfare of poultry housing systems in the elimination of pathogenic Escherichia coli strains in vitro
Ewelina Pyzik1, Urban-Chmiel Renata1, Korona-Głowniak Izabela2, Suśniak Katarzyna2, Ciesielka Marzanna3, Całka Paulina3, Dec Marta1, Herman-Ostrzyżek Klaudia1
1Department of Veterinary Prevention and Avian Diseases, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Poland
2Department of Pharmaceutical Microbiology, Faculty of Pharmacy, Medical University of Lublin, Poland
3Department of Forensic Medicine, Faculty of Medicine, Medical University of Lublin, Poland
The high global consumption of poultry raises concerns about the risks associated with the prevalence of APEC (Avian Pathogenic E. coli) strains, which cause colibacillosis in poultry. A major challenge in controlling these infections is the limited effectiveness of antibiotic therapy due to bacterial resistance associated with biofilm formation. The aim of this study was to develop and evaluate the effectiveness of an experimental bacteriophage preparation intended to improve the welfare of poultry housing systems by eliminating APEC strains in vitro. Bacteriophages were isolated from the feces of ducks, turkeys, and broiler chickens collected from litter. Purification and propagation of the isolated phages, determination of lytic spectra, and titer were carried out using the double-layer agar method on 0.7% LB agar. Morphological characterization of phages was performed by TEM microscopy (Xie et al., 2005). The experimental preparation consisted of a cocktail of lysate of 9 bacteriophages specific for APEC, concentrated in TM buffer to a final titer ≥10⁹ PFU/mL. The in vitro activity of phage cocktail was evaluated based on its ability to eradicate biofilms formed in microtiter plates containing LB medium. Analysis enabled the isolation of phages exhibiting lytic activity against the tested APEC strains. Morphological examination in TEM revealed virions indicating that they belong to the class Caudoviricetes, Myophages, based on their virion morphology. In vitro evaluation of phage kinetics, based on their ability to eradicate biofilms formed by APEC strains, demonstrated an antibacterial efficacy exceeding 70%, which can be considered substantial. Moreover, the developed preparation showed high effectiveness in in vivo reaching 82.6%. The most effective control of APEC strains is achieved using bacteriophages isolated from the specific poultry species targeted. Combining different groups of phages can substantially enhance the antibacterial activity of phage preparations. The preparation developed from bacteriophages isolated from various poultry species may offer a straightforward strategy to broaden the application of phages for improving the welfare of poultry. This research was funded by the National Science Centre, Poland, OPUS27 project No 2024/53/B/NZ6/00046.
Environmental isolation of bacteriophages for the development of phage libraries targeting Klebsiella spp
Katherina Aubrey P Resente1,4, Reuel M Bennett1,2,3,4, Donna May D Papa1,2,3
1Graduate School, University of Santo Tomas, Philippines
2Research Center for the Natural and Applied Sciences, University of Santo Tomas, Philippines
3Department of Biological Sciences, College of Science, University of Santo Tomas, Philippines
4Collection of Microbial Strains, Research Center for the Natural and Applied Sciences, University of Santo Tomas, Philippines
The rise of antibiotic-resistant bacterial infections has created an urgent need for alternative antimicrobial strategies. Klebsiella spp. has emerged as a major opportunistic pathogen responsible for various hospital-acquired infections (HAIs) and is increasingly associated with multidrug resistance. Phage therapy is a promising alternative method that uses bacteriophages, which are viruses that infect and lyse bacteria, as targeted antibacterial agents. This study aims to isolate and characterize bacteriophages from diverse aquatic habitats in the Philippines that infect Klebsiella pneumoniae and other related species. Aquatic environments are significant reservoirs of bacteriophages due to their high microbial density and ecological diversity. Phages are highly abundant in these systems, and their diversity and host specificity are influenced by environmental factors such as temperature, salinity, and nutrient availability. Sewage and wastewater, in particular, contain high viral loads and phages capable of infecting clinically relevant pathogens, while freshwater, brackish, and coastal environments harbor distinct phage populations. Collectively, these environments provide valuable sources for isolating bacteriophages with potential activity against Klebsiella spp. Genotypic methods were used to characterize isolated bacteriophages and assess their lytic activity against Klebsiella spp. Selected isolates will undergo whole-genome sequencing to evaluate genetic composition and screen for virulence and antibiotic resistance genes, ensuring their safety and therapeutic potential. The findings may contribute to the development of a diverse bacteriophage library and support phage cocktail formulations against Klebsiella infections. Additionally, this study may provide insights into the diversity of bacteriophages in Philippine aquatic environments and their potential as alternative antimicrobial agents.
CRISPRi-mediated regulation in multicellular genetic circuits (Flash-talk)
Abhinav Pujar1, Anchita Sharma1, Hadrien Hadi Barras1, Guillermo Rodrigo2, Manish Kushwaha1
1Université Paris-Saclay, INRAe, AgroParisTech, Micalis Institute, 78352 Jouy-en-Josas, France
2Institute for Integrative Systems Biology (I2SysBio), CSIC-University of Valencia, 76980 Paterna, Spain
As synthetic genetic circuits grow more complex, distributing computation across multiple cell populations is important to reduce metabolic burden and improve system robustness. For these multicellular systems to work effectively, cells need reliable and scalable ways to communicate. Small-molecule signals, such as quorum sensing molecules, are often used, but they are limited in the number of distinct messages they can carry and the amount of information they can transmit. DNA-based communication through bacteriophage transduction offers a versatile, information-rich alternative that can encode complex instructions and enable modular, programmable circuit design. Here, we present a library of five M13 phagemid variants with distinct replication origins, including those based on the Standard European Vector Architecture (SEVA) family, designed to tune the growth and secretion dynamics of sender strains. We paired these phagemids with an intercellular CRISPRi system for precise quantification of genetic payload delivery. Together, these strategies lay the foundation for programmable, DNA-mediated communication in multicellular synthetic consortia and open exciting possibilities for distributed, multicellular genetic computation.
Phylogenetic analysis and characterization of the activity of three bacteriophages isolated from poultry living environments, ECBR1, ECBR3 and ECBR4, against pathogenic APEC strains
Renata Urban-Chmiel1, Pyzik Ewelina1, Ciesielka Marzanna2, Całka Paulina2, Korona-Głowniak Izabela3, Suśniak Katarzyna3, Andrzej Krajka4, Dec Marta1, Herman-Ostrzyżek Klaudia1
1Department of Veterinary Prevention and Avian Diseases, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Poland
2Department of Forensic Medicine, Faculty of Medicine, Medical University of Lublin, Poland
3Department of Pharmaceutical Microbiology, Faculty of Pharmacy, Medical University of Lublin, Poland
4Department of Forensic Medicine, Faculty of Medicine, Medical University of Lublin; Institute of Computer Science and Mathematics, Department of Fundamentals of Computer Science, Poland
High poultry consumption is one of the factors contributing to the common occurrence of pathogenic APEC (avian pathogenic E.coli) strains inducing colibacillosis in poultry. The global problem of drug-resistance among pathogens has also led to a number of measures taken to reduce the use of antibiotics in poultry. The limited possibilities for fighting bacterial infections have prompted the search for alternative methods to antibiotics with using bacteriophages. The aim of the study was to characterize APEC-specific phages isolated from poultry as potential tools for controlling bacteria. The study was conducted using faecal samples from broiler chickens kept in free-range farming systems. Phenotypic characterization of phages was based on TEM microscopy, the range of lytic activity against APEC strains, and the stability of titres in standard and altered pH conditions. Genetic analysis of phages was based on genome analysis and comparison with the genomes of other phages. The aim of the analysis was to determine the taxonomic identity of the phages and to confirm their strictly lytic nature by analysing their complete genome. Three bacteriophages, ECBR1, ECBR3, ECBR4, exhibiting lytic properties against APEC strains, were isolated. Morphological analysis (TEM) showed that all phages belonged to Caudoviricetes. The lytic titre was 1010 PFU/ml. Lytic activity against the APEC ranged from 43.5% to 76.1%. The study confirmed that phages were lytic, and lytic genes were mapped in their genome, including RIIA and RIIB lysis, LTs, and LIN; no AMR genes were detected. The phages showed low phylogenetic similarity to one another, at a maximum level of 30%. The results indicate that APEC-specific phages have significant antibacterial potential. This creates the potential for their use as alternatives to antibiotics to control infections, especially given that costs of developing phage preparations is much lower than the cost of producing antibiotics. Due to the lack of full knowledge of the metabolism, kinetics and their effects on eukaryotic cells, further research is essential. This research was fully funded by the National Science Centre, Poland, OPUS27 project No 2024/53/B/NZ6/00046.
Identifying loci in Clostridioides difficile bacteriophage ΦCD27 for therapeutic cargo insertion
Samiksha Venkatesan1, Ernesto Abel-Santos2,3, Rachel McMullan4, Ilias Kounatidis4, Terry Bilverstone1
1Anaerobes in Medicine (AiM Lab), School of Life, Health and Chemical Sciences, The Open University, Milton Keynes, United Kingdom
2Department of Chemistry and Biochemistry, University of Nevada–Las Vegas, Las Vegas, USA
3Nevada Institute of Personalized Medicine, University of Nevada–Las Vegas, Las Vegas, USA
4School of Life, Health and Chemical Sciences, The Open University, Milton Keynes, United Kingdom
Clostridioides difficile is the leading cause of hospital-associated diarrhoea in the Western world. This bacterial pathogen is resistant to several antibiotics, and those that are routinely used as treatment worsen the causative gut microbiome dysbiosis. Bacteriophage (phage) therapy is an ideal alternative due to their species-specific activity, which should facilitate the restoration of a diverse microbiome and prevent recurrent infection. However, all known C. difficile phages are temperate, whereby they can integrate into the host genome and form lysogens, which reduces their therapeutic potential. Thus, this project seeks to engineer a C. difficile phage ΦCD27 with ‘therapeutic cargo’ to improve its host killing capability and prevent lysogen formation. Three putative sites along the ΦCD27 genome were determined for knocking-in the therapeutic cargo in two inserts of 679 and 807 bp respectively. These loci were predicted to have minimal polar effects on adjacent genes. CRISPR-Cas9 plasmids containing the first insert were assembled and conjugated into a lysogenised strain of the host. Colony PCR screening indicated that the first insert had integrated into two of the three loci. Subsequently, CRISPR-Cas9 plasmids containing the second insert were assembled and conjugated into mutant lysogens containing the first insert. Colony PCR screening revealed that the second insert had integrated into one of the two loci, indicating that the full sequence of the therapeutic cargo (1486 bp) had successfully been knocked into one locus along the ΦCD27 genome. These results show promise at obtaining engineered C. difficile phages, which has only been demonstrated once in the published literature. Future work will involve comparing wild-type and engineered ΦCD27 in their ability to infect and control host growth in various in vitro assays. These findings will help advance the field of C. difficile phage therapy, bringing us closer to a much-needed alterative treatment.
Recombinant K1-type capsule depolymerase potentiates phage infection against a non-permissive Klebsiella pneumoniae capsule type
Charlotte A Woolley1,2, Matthew E Wand 3, J Mark Sutton3,4, Simon J Moore2
1School of Biological and Behavioural Sciences, Queen Mary, University of London, London, UK
2Department of Life Science, Faculty of Natural Sciences, Imperial College London, London, UK
3Countermeasures Development, Evaluation and Preparedness, Public Health Microbiology, UK Health Security Agency, Porton Down, UK
4Institute of Pharmaceutical Science, School of Cancer & Pharmaceutical Sciences, King’s College London, UK
Klebsiella pneumoniae is a leading cause of multidrug-resistant infections, and phage therapy is gaining traction as an alternative treatment approach. However, phage host range is often restricted by the bacterial capsule, which varies widely. Capsule depolymerases, carried by phage as part of their tail fibres, strip the protective polysaccharide capsule and can potentiate phage infection against K types outside a phage’s native host range. Here, we expressed three capsule depolymerases via conventional recombinant approaches and via cell-free protein synthesis (CFPS): two K64-specific depolymerases identified from prophages in K. pneumoniae strain T76 (KpT76-depol1 and KpT76-depol2), and the previously characterised K1-specific depolymerase K1-ORF34. All three showed good expression and solubility by both expression routes, but only K1-ORF34 showed reproducible depolymerase activity when expressed recombinantly or through CFPS. We then tested whether CFPS-produced K1-ORF34 could potentiate phage infection across a panel of K1-type K. pneumoniae strains spanning different O-antigen types. Co-application of K1-ORF34 with KpT76 rescued plaque formation in one strain: K. pneumoniae M4 (K1 capsule, O2ab O-antigen). This occurred in a dose-dependent manner, with comet-like spreading plaques observed at 1 µg/mL and discrete plaques at 0.1 µg/mL, while KpT76 in the absence of K1-ORF34 produced no plaques. These results demonstrate that an active depolymerase matched to a target capsule can potentiate phage infection independent of native phage host range, thus supporting depolymerase-phage combination approaches against K. pneumoniae.
