Novel Phage Lysin Abp013 against Acinetobacter baumannii

Identifying phage Lysins through genomic analysis of prophages from Acinetobacter baumannii

Acinetobacter baumannii is a Gram-negative opportunistic pathogen, responsible for nosocomial infections worldwide. In recent years, this microorganism has acquired resistance to various antibiotics, prompting the World Health Organization (WHO) to declare carbapenem-resistant A. baumannii (CRAB) a critical priority microorganism requiring urgent attention and the development of new therapeutic options. Here, we screened for prophages in 158 genomes of A. baumannii, comprising 139 complete genomes from the Bacterial and Viral Bioinformatics Resource Center (BV-BRC), and 19 newly sequenced clinical isolates. Additionally, we conducted phylogenetic analyses of prophages, highlighting their diversity and local clustering. The analyzed genomes harbored at least two prophage regions, resulting in the identification of a total of 950 prophage regions, of which 348 were considered complete prophages through software analysis and manual curation, while the remainder may represent prophage remnants. The complete prophages ranged from 28.6 to 103.9 kbp, with an average GC content of 39%. Based on genomic similarity, only 18 complete prophages were taxonomically classified to the genus Vieuvirus. Among all identified complete prophages, we identified 166 genes encoding for putative lysins, while prophage regions that were not considered complete could also harbor putative lysins. These findings highlight the abundance of prophage-encoded lysins in A. baumannii genomes, which are promising therapeutic agents for combating A. baumannii infections, particularly in the face of rising antibiotic resistance.

Surface charge of the C-terminal helix is crucial for antibacterial activity of endolysin against Gram-negative bacteria

BACKGROUNDS

Endolysins are promising alternatives to antibiotics because they can lyse bacterial cells rapidly with a low risk of resistance development, however, their effectiveness against Gram-negative bacteria is hindered by the presence of the outer membrane present in Gram-negative bacteria. Several endolysins with amphipathic helices at the C-terminus have been reported to have intrinsic antibacterial activity against Gram-negative bacteria but their action mechanism is not fully elucidated.

METHODS

The sequence alignment analysis was assessed with the CLC Main workbench 7, and His-tagged endolysins were purified with affinity chromatography. Site-directed mutagenesis was used to generate mutations in the endolysin to make various endolysin mutants. The muralytic activity of the endolysin against Gram-negative bacteria was analyzed using a turbidity reduction assay and the antibacterial activities of the endolysins were assessed through a viable cell counting assay.

RESULTS

We identified two endolysins, LysTS3 and LysTS6, both of which have similar sequences and structures including the amphipathic helices at their C-terminus. LysTS6 exhibited significantly higher antibacterial activity against Gram-negative bacteria compared to LysTS3 even though both enzymes have similar muralytic activity against the outer membrane-permeabilized Gram-negative bacteria. Systematic truncation and bioinformatic analysis of these two endolysins revealed a major difference in the charge on the surface of their C-terminal helices, suggesting the possibility that the charge on this helix can determine the antibacterial activity of the endolysins against Gram-negative bacteria. We could enhance the activity of LysTS3 against Gram-negative bacteria by replacing Ala156 and Glu160 with lysine and alanine, respectively, the amino acid residues at the structurally equivalent positions in LysTS6. A similar activity boost was also seen in LysSPN1S and LysJEP4 when the surface charge of the C-terminal amphipathic helix was altered to be more positive through the modification of the surface-exposed amino acid residues.

CONCLUSIONS

The antibacterial activity of endolysin against Gram-negative bacteria could be enhanced by adjusting the surface charge on the C-terminal amphipathic helix to more positive, suggesting that the positive surface charge on the C-terminal amphipathic helix of endolysin is crucial for its penetration of outer membrane to reach peptidoglycan layer of Gram-negative bacteria.

Recent insights on phage therapy against multidrug-resistant Acinetobacter baumannii

Acinetobacter baumannii is a prevalent clinical pathogen commonly found to be multidrug-resistant (MDR), causing serious to life-threatening infections, particularly hospital-acquired infections with limited therapeutic options. The MDR phenotype developed against this critical pathogen is increasingly developed globally, reaching a pan-drug-resistant phenotype conferring non-susceptibility to all antimicrobials used in its treatment according to the standard guidelines. Therefore, it is critical to develop innovative treatment approaches, such as phage therapy, considering the rise in drug-resistant A. baumannii infections. In this review, we highlight and discuss the up-to-date antimicrobial resistance of A. baumannii, the use of phages, their limitations, and future perspectives in treating A. baumannii infections. In addition, the combination of phages with antimicrobials, preclinical and clinical studies including pharmacokinetics and pharmacodynamics properties have been discussed.

Bactericidal Effect of a Novel Phage Endolysin Targeting Multi-Drug-Resistant Acinetobacter baumannii

BACKGROUND/OBJECTIVES

Infections with antibiotic-resistant Gram-negative pathogens represent a major global threat to public health. Acinetobacter baumannii is a highly important nosocomial pathogen causing severe and life-threatening infections, like pneumonia, wound infections, or sepsis. It is often resistant even against last-resort antibiotics, such as carbapenems, and can persist in healthcare settings. Artilysin®s are a novel class of endolysins targeted against multidrug-resistant bacteria.

METHODS

Antibacterial activity of Art-Top3 was determined by broth microdilution, in vitro assays and in the Galleria mellonella infection model. The toxicity of Art-Top3 on red blood cells, endothelial and epithelial cells was analyzed using the MTT assay.

RESULTS

Here, we report on a new Artilysin® Art-Top3 that is active against A. baumannii and led to a 105-fold reduction in viable A. baumannii after five minutes of exposure. Art-Top3 showed activity against A. baumannii biofilms in static and dynamic experimental infection models. Furthermore, upon infection with carbapenem-resistant A. baumannii patient isolates, Art-Top3 was able to rescue human primary cells in vitro and larvae of Galleria mellonella in an in vivo infection model. Art-Top3 did not lyse human red blood cells and showed activity in human serum, indicating a low toxicity and high stability of Art-Top3 in vitro.

CONCLUSION

Our findings collectively establish that Art-Top3 might be a candidate for novel therapeutic strategies of infections caused by multidrug-resistant A. baumannii pathogens.

Comprehensive Approaches to Combatting Acinetobacter baumannii Biofilms: From Biofilm Structure to Phage-Based Therapies

Acinetobacter baumannii-a multidrug-resistant (MDR) pathogen that causes, for example, skin and soft tissue wounds; urinary tract infections; pneumonia; bacteremia; and endocarditis, particularly due to its ability to form robust biofilms-poses a significant challenge in clinical settings. This structure protects the bacteria from immune responses and antibiotic treatments, making infections difficult to eradicate. Given the rise in antibiotic resistance, alternative therapeutic approaches are urgently needed. Bacteriophage-based strategies have emerged as a promising solution for combating A. baumannii biofilms. Phages, which are viruses that specifically infect bacteria, offer a targeted and effective means of disrupting biofilm and lysing bacterial cells. This review explores the current advancements in bacteriophage therapy, focusing on its potential for treating A. baumannii biofilm-related infections. We described the mechanisms by which phages interact with biofilms, the challenges in phage therapy implementation, and the strategies being developed to enhance its efficacy (phage cocktails, engineered phages, combination therapies with antibiotics). Understanding the role of bacteriophages in both biofilm disruption and in inhibition of its forming could pave the way for innovative treatments in combating MDR A. baumannii infections as well as the prevention of their development.

Comprehensive retrospect and future perspective on bacteriophage and cancer

BACKGROUND

Researchers gradually focus on the relationship between phage and cancer.

OBJECTIVE

To summarize the research hotspots and trends in the field of bacteriophage and cancer.

METHODS

The downloaded articles were searched from the Web of Science Core Collection database from January 2008 to June 2023. Bibliometric analysis was carried out through CiteSpace, including the analysis of cooperative networks (country/region, institution, and author), co-citations of references, and key words.Visual analysis of three topics, including gut phage, phage and bacteria, and phage and tumor, was conducted.

RESULTS

Overall, the United States and China have the most phage-related research. In terms of gut phage, the future research directions are "gut microbiome", "database" and "microbiota". The bursting citations explored the phage-dominated viral genome to discover its diversity and individual specificity and investigated associations among bacteriome, metabolome, and virome. In terms of phage and bacteria, "lipopolysaccharide" and "microbiota" are future research directions. Future research hotspots should mainly concentrate on the further exploration and application of phage properties. As for phages and tumors, the future research directions should be "colorectal cancer", "protein" and "phage therapy". Future directions are likely to focus on the research on phages in cancer mechanisms, cancer diagnosis, and cancer treatment combined with genetic engineering techniques.

CONCLUSION

Phage therapy would become a hot spot and research direction of tumor and phage research, and the relationship between phage and tumor, especially colorectal cancer (CRC), is expected to be further explored.

LysJEP8: A promising novel endolysin for combating multidrug-resistant Gram-negative bacteria

Antimicrobial resistance (AMR) is an escalating global health crisis, driven by the overuse and misuse of antibiotics. Multidrug-resistant Gram-negative bacteria, such as Pseudomonas aeruginosa, Acinetobacter baumannii, and Klebsiella pneumoniae, are particularly concerning due to their high morbidity and mortality rates. In this context, endolysins, derived from bacteriophages, offer a promising alternative to traditional antibiotics. This study introduces LysJEP8, a novel endolysin derived from Escherichia phage JEP8, which exhibits remarkable antimicrobial activity against key Gram-negative members of the ESKAPE group. Comparative assessments highlight LysJEP8's superior performance in reducing bacterial survival rates compared to previously described endolysins, with the most significant impact observed against P. aeruginosa, and notable effects on A. baumannii and K. pneumoniae. The study found that LysJEP8, as predicted by in silico analysis, worked best at lower pH values but lost its effectiveness at salt concentrations close to physiological levels. Importantly, LysJEP8 exhibited remarkable efficacy in the disruption of P. aeruginosa biofilms. This research underscores the potential of LysJEP8 as a valuable candidate for the development of innovative antibacterial agents, particularly against Gram-negative pathogens, and highlights opportunities for further engineering and optimization to address AMR effectively.

Endolysins: a new antimicrobial agent against antimicrobial resistance. Strategies and opportunities in overcoming the challenges of endolysins against Gram-negative bacteria

Antibiotic-resistant bacteria are rapidly emerging, and the increasing prevalence of multidrug-resistant (MDR) Acinetobacter baumannii poses a severe threat to humans and healthcare organizations, due to the lack of innovative antibacterial drugs. Endolysins, which are peptidoglycan hydrolases encoded by a bacteriophage, are a promising new family of antimicrobials. Endolysins have been demonstrated as an effective therapeutic agent against bacterial infections of A. baumannii and many other Gram-positive and Gram-negative bacteria. Endolysin research has progressed from basic in vitro characterization to sophisticated protein engineering methodologies, including advanced preclinical and clinical testing. Endolysin are therapeutic agent that shows antimicrobial properties against bacterial infections caused by drug-resistant Gram-negative bacteria, there are still barriers to their implementation in clinical settings, such as safety concerns with outer membrane permeabilizers (OMP) use, low efficiency against stationary phase bacteria, and stability issues. The application of protein engineering and formulation techniques to improve enzyme stability, as well as combination therapy with other types of antibacterial drugs to optimize their medicinal value, have been reviewed as well. In this review, we summarize the clinical development of endolysin and its challenges and approaches for bringing endolysin therapies to the clinic. This review also discusses the different applications of endolysins.

Characterization and efficacy against carbapenem-resistant Acinetobacter baumannii of a novel Friunavirus phage from sewage

Carbapenem-resistant Acinetobacter baumannii (CRAB) has become a new threat in recent years, owing to its rapidly increasing resistance to antibiotics and new effective therapies are needed to combat this pathogen. Phage therapy is considered to be the most promising alternative for treating CRAB infections. In this study, a novel phage, Ab_WF01, which can lyse clinical CRAB, was isolated and characterized from hospital sewage. The multiplicity of infection, morphology, one-step growth curve, stability, sensitivity, and lytic activity of the phage were also investigated. The genome of phage Ab_WF01 was 41, 317 bp in size with a GC content of 39.12% and encoded 51 open reading frames (ORFs). tRNA, virulence, and antibiotic resistance genes were not detected in the phage genome. Comparative genomic and phylogenetic analyses suggest that phage Ab_WF01 is a novel species of the genus Friunavirus, subfamily Beijerinckvirinae, and family Autographiviridae. The in vivo results showed that phage Ab_WF01 significantly increased the survival rate of CRAB-infected Galleria mellonella (from 0% to 70% at 48 h) and mice (from 0% to 60% for 7 days). Moreover, after day 3 post-infection, phage Ab_WF01 reduced inflammatory response, with strongly ameliorated histological damage and bacterial clearance in infected tissue organs (lungs, liver, and spleen) in mouse CRAB infection model. Taken together, these results show that phage Ab_WF01 holds great promise as a potential alternative agent with excellent stability for against CRAB infections.

Engineering strategies and challenges of endolysin as an antibacterial agent against Gram-negative bacteria

Bacteriophage endolysin is a novel antibacterial agent that has attracted much attention in the prevention and control of drug-resistant bacteria due to its unique mechanism of hydrolysing peptidoglycans. Although endolysin exhibits excellent bactericidal effects on Gram-positive bacteria, the presence of the outer membrane of Gram-negative bacteria makes it difficult to lyse them extracellularly, thus limiting their application field. To enhance the extracellular activity of endolysin and facilitate its crossing through the outer membrane of Gram-negative bacteria, researchers have adopted physical, chemical, and molecular methods. This review summarizes the characterization of endolysin targeting Gram-negative bacteria, strategies for endolysin modification, and the challenges and future of engineering endolysin against Gram-negative bacteria in clinical applications, to promote the application of endolysin in the prevention and control of Gram-negative bacteria.

Gram-negative endolysins: overcoming the outer membrane obstacle

Our ability to control the growth of Gram-negative bacterial pathogens is challenged by rising antimicrobial resistance and requires new approaches. Endolysins are phage-derived enzymes that degrade peptidoglycan and therefore offer potential as antimicrobial agents. However, the outer membrane (OM) of Gram-negative bacteria impedes the access of externally applied endolysins to peptidoglycan. This review highlights recent advances in the discovery and characterization of natural endolysins that can breach the OM, as well as chemical and engineering approaches that increase antimicrobial efficacy of endolysins against Gram-negative pathogens.

Heterologous expression and purification of the phage lysin-like bacteriocin LysL from Lactococcus lactis LAC460

The wild-type Lactococcus lactis strain LAC460 produces two bacteriocin-like phage lysins, LysL and LysP. This study aimed to produce and secrete LysL in various heterologous hosts and an in vitro cell-free expression system for further functional studies. Initially, the lysL gene from L. lactis LAC460 was cloned into Lactococcus cremoris NZ9000 and L. lactis N8 strains, with and without the usp45 signal sequence (SSusp45), under a nisin-inducible promoter. Active LysL was primarily produced intracellularly in recombinant L. lactis N8, with some secretion into the supernatant. Recombinant L. cremoris NZ9000 lysed upon nisin induction, indicating successful lysL expression. However, fusion with Usp45 signal peptide (SPUsp45-LysL) weakened LysL activity, likely due to incomplete signal peptide cleavage during secretion. Active LysL was also produced in vitro, and analysed in SDS-PAGE, giving a 42-kDa band. However, the yield of LysL protein was still low when produced from recombinant lactococci or by in vitro expression system. Therefore, His-tagged LysL was produced in Escherichia coli BL21(DE3). Western blot confirmed the intracellular production of about 44-kDa His-tagged LysL in E. coli. His-tagged active LysL was then purified by Ni-NTA affinity chromatography yielding sufficient 4.34 mg of protein to be used in future functional studies.

Design strategies for positively charged endolysins: Insights into Artilysin development

Endolysins are bacteriophage-encoded enzymes that can specifically degrade the peptidoglycan layer of bacterial cell wall, making them an attractive tool for the development of novel antibacterial agents. The use of genetic engineering techniques for the production and modification of endolysins offers the opportunity to customize their properties and activity against specific bacterial targets, paving the way for the development of personalized therapies for bacterial infections. Gram-negative bacteria possess an outer membrane that can hinder the action of recombinantly produced endolysins. However, certain endolysins are capable of crossing the outer membrane by virtue of segments that share properties resembling those of cationic peptides. These regions increase the affinity of the endolysin towards the bacterial surface and assist in the permeabilization of the membrane. In order to improve the bactericidal effectiveness of endolysins, approaches have been implemented to increase their net charge, including the development of Artilysins containing positively charged amino acids at one end. At present, there are no specific guidelines outlining the steps for implementing these modifications. There is an ongoing debate surrounding the optimal location of positive charge, the need for a linker region, and the specific amino acid composition of peptides for modifying endolysins. The aim of this study is to provide clarity on these topics by analyzing and comparing the most effective modifications found in previous literature.

Bacteriophages and their derived enzymes as promising alternatives for the treatment of Acinetobacter baumannii infections

Nosocomial infections with the opportunistic bacterium Acinetobacter baumannii pose a severe challenge to clinical treatment, which is aggravated by the increasing occurrence of multi-drug resistance, especially resistance to carbapenems. The use of phage therapy as an alternative and supplement to the current antibiotics has become an important research topic in the post-antibiotic era. This review summarizes in vivo and in vitro studies on phage therapy against multi-drug-resistant A. baumannii infection that have used different approaches, including treatment with a single phage, combination with other phages or non-phage agents, and administration of phage-derived enzymes. We also briefly discuss the current challenges of phage-based therapy as well as promising approaches for the treatment of A. baumannii infection in the future.

Beyond antibiotics: phage-encoded lysins against Gram-negative pathogens

Antibiotics remain the frontline agents for treating deadly bacterial pathogens. However, the indiscriminate use of these valuable agents has led to an alarming rise in AMR. The antibiotic pipeline is insufficient to tackle the AMR threat, especially with respect to the WHO critical category of priority Gram-negative pathogens, which have become a serious problem as nosocomial and community infections and pose a threat globally. The AMR pandemic requires solutions that provide novel antibacterial agents that are not only effective but against which bacteria are less likely to gain resistance. In this regard, natural or engineered phage-encoded lysins (enzybiotics) armed with numerous features represent an attractive alternative to the currently available antibiotics. Several lysins have exhibited promising efficacy and safety against Gram-positive pathogens, with some in late stages of clinical development and some commercially available. However, in the case of Gram-negative bacteria, the outer membrane acts as a formidable barrier; hence, lysins are often used in combination with OMPs or engineered to overcome the outer membrane barrier. In this review, we have briefly explained AMR and the initiatives taken by different organizations globally to tackle the AMR threat at different levels. We bring forth the promising potential and challenges of lysins, focusing on the WHO critical category of priority Gram-negative bacteria and lysins under investigation for these pathogens, along with the challenges associated with developing them as therapeutics within the existing regulatory framework.

PlyKp104, a Novel Phage Lysin for the Treatment of Klebsiella pneumoniae, Pseudomonas aeruginosa, and Other Gram-Negative ESKAPE Pathogens

Klebsiella pneumoniae and Pseudomonas aeruginosa are two leading causes of burn and wound infections, pneumonia, urinary tract infections, and more severe invasive diseases, which are often multidrug resistant (MDR) or extensively drug resistant. Due to this, it is critical to discover alternative antimicrobials, such as bacteriophage lysins, against these pathogens. Unfortunately, most lysins that target Gram-negative bacteria require additional modifications or outer membrane permeabilizing agents to be bactericidal. We identified four putative lysins through bioinformatic analysis of Pseudomonas and Klebsiella phage genomes in the NCBI database and then expressed and tested their intrinsic lytic activity in vitro. The most active lysin, PlyKp104, exhibited >5-log killing against K. pneumoniae, P. aeruginosa, and other Gram-negative representatives of the multidrug-resistant ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, K. pneumonia, Acinetobacter baumannii, P. aeruginosa, and Enterobacter species) without further modification. PlyKp104 displayed rapid killing and high activity over a wide pH range and in high concentrations of salt and urea. Additionally, pulmonary surfactants and low concentrations of human serum did not inhibit PlyKp104 activity in vitro. PlyKp104 also significantly reduced drug-resistant K. pneumoniae >2 logs in a murine skin infection model after one treatment of the wound, suggesting that this lysin could be used as a topical antimicrobial against K. pneumoniae and other MDR Gram-negative infections.

Antibacterial activity of vB_AbaM_PhT2 phage hydrophobic amino acid fusion endolysin, combined with colistin against Acinetobacter baumannii

Phage lytic enzymes are promising antimicrobial agents. In this study, an endolysin derived from vB_AbaM_PhT2 (vPhT2), was identified. This endolysin represented the conserved lysozyme domain. Recombinant endolysin (lysAB- vT2) and hydrophobic fusion endolysin (lysAB-vT2-fusion) were expressed and purified. Both endolysins showed lytic activity against bacterial crude cell wall of Gram-negative bacteria. The MIC of lysAB-vT2-fusion was 2 mg/ml corresponding to 100 µM, while the MIC of lysAB-vT2 was more than 10 mg/ml (400 µM). Combination of lysAB-vT2-fusion with colistin, polymyxin B or copper was synergistic against A. baumannii (FICI value as 0.25). Antibacterial activity of lysAB-vT2-fusion plus colistin at the fractional inhibitory concentrations (FICs) revealed that it can inhibit Escherichia coli, Klebsiella pneumoniae and various strains of extremely drug-resistant A. baumannii (XDRAB) and phage resistant A. baumannii. The lysAB- vT2-fusion still retained its antibacterial activity after incubating the enzyme at 4, 20, 40 and 60 °C for 30 min. The lysAB-vT2-fusion could inhibit the mature biofilm, and incubation of lysAB-vT2-fusion with T24 human cells infected with A. baumannii led to a partial reduction of LDH release from T24 cells. In summary, our study highlights the antimicrobial ability of engineered lysAB-vT2-fusion endolysin, which can be applied for the control of A. baumannii infection.

Identification of Three Campylobacter Lysins and Enhancement of Their Anti-Escherichia coli Efficacy Using Colicin-Based Translocation and Receptor-Binding Domain Fusion

The emergence of multidrug-resistant Escherichia coli, which poses a major threat to public health, has motivated the development of numerous alternative antimicrobials. Lysins are bacteriophage- and bacterium-derived peptidoglycan hydrolases that represent a new antibiotic treatment targeting bacterial cell walls. However, the bactericidal effect of native lysins on Gram-negative bacteria is restricted by the presence of an outer membrane. Here, we first evaluated the antibacterial activity of three Campylobacter-derived lysins (Clysins) against E. coli. To improve their transmembrane ability and antibacterial activities, six engineered Clysins were constructed by fusing with the translocation and receptor-binding (TRB) domains from two types of colicins (colicin A [TRBA] and colicin K [TRBK]), and their biological activities were determined. Notably, engineered lysin TRBK-Cly02 exhibited the highest bactericidal activity against the E. coli BL21 strain, with a reduction of 6.22 ± 0.34 log units of cells at a concentration of 60.1 μg/mL, and formed an observable inhibition zone even at a dose of 6.01 μg. Moreover, TRBK-Cly02 killed E. coli dose dependently and exhibited the strongest bactericidal activity at pH 6. It also exhibited potential bioactivity against multidrug-resistant E. coli clinical isolates. In summary, this study identified three lysins from Campylobacter strains against E. coli, and the enhancement of their antibacterial activities by TRB domains fusion may allow them to be developed as potential alternatives to antibiotics. IMPORTANCE Three lysins from Campylobacter, namely, Clysins, were investigated, and their antibacterial activities against E. coli were determined for the first time. To overcome the restriction of the outer membrane of Gram-negative bacteria, we combined the TRB domains of colicins with these Clysins. Moreover, we discovered that the Clysins fused with TRB domains from colicin K (TRBK) killed E. coli more effectively, and this provides a new foundation for the development of novel bioengineered lysins by employing TRBK constructs that target outer membrane receptor/transport systems. One of the designed lysins, TRBK-Cly02, exhibited potent bactericidal efficacy against E. coli strains and may be used for control of multidrug-resistant clinical isolates. The results suggest that TRBK-Cly02 can be considered a potential antibacterial agent against pathogenic E. coli.

Recent Advances in Phage-Based Therapeutics for Multi-Drug Resistant Acinetobacter baumannii

Acinetobacter baumannii is an important opportunistic pathogen common in clinical infections. Phage therapy become a hot research field worldwide again after the post-antibiotic era. This review summarizes the important progress of phage treatments for A. baumannii in the last five years, and focus on the new interesting advances including the combination of phage and other substances (like photosensitizer), and the phage encapsulation (by microparticle, hydrogel) in delivery. We also discuss the remaining challenges and promising directions for phage-based therapy of A. baumannii infection in the future, and the innovative combination of materials in this area may be one promising direction.

inPhocus: Current State and Challenges of Phage Research in Singapore

Bacteriophages and phage-derived proteins are a promising class of antibacterial agents that experience a growing worldwide interest. To map ongoing phage research in Singapore and neighboring countries, Lee Kong Chian School of Medicine, Nanyang Technological University Singapore (NTU) and Yong Loo Lin School of Medicine, National University of Singapore (NUS) recently co-organized a virtual symposium on Bacteriophage and Bacteriophage-Derived Technologies, which was attended by more than 80 participants. Topics were discussed relating to phage life cycles, diversity, the roles of phages in biofilms and the human gut microbiome, engineered phage lysins to combat polymicrobial infections in wounds, and the challenges and prospects of clinical phage therapy. This perspective summarizes major points discussed during the symposium and new perceptions that emerged after the panel discussion.

The Potential Role for Phage Therapy for Genetic Modification of Cutaneous Diseases

Antimicrobial resistance has become increasingly common across the globe, claiming over 33,000 lives annually in Europe and 23,000 lives in the United States alone. The problem lies in trying to find potential solutions capable of tackling resistance and being able to fight infections that may resist various antimicrobials. Since Alexander Fleming's discovery in 1928, every antimicrobial synthesized in the past 70 years has developed at least one or more strands of resistant bacteria. One particular alternative to antimicrobials has brought hope to many in the scientific community; its name is the bacteriophage. Bacteriophages are viruses that can replicate within bacteria triggering genetic alterations and changes in pathways of protein expression by encoding a few to hundreds of genes within their genomes. The bacteriophage can hijack the cell, using the cell's genetic apparatus to replicate within the bacterium until bacterial lysis. This therapy has been used in the genodermatosis Netherton syndrome which has been associated with the increased risk of Staphylococcus aureus infections. Emerging data support the potential role of bacteriophage therapy for Cutibacterium acnes in acne vulgaris, with a potential role in genetic disorders with severe acne vulgaris including Apert's syndrome. Bacteriophages hold benefits for genodermatoses associated with recurrent cutaneous infections, i.e. the immunodeficiencies with distinctive cutaneous features as well as conditions such as atopic dermatitis in which bacterial colonization plays a strong role.