Research Projects

(1) Rationale of the Study: The emergence of carbapenem-resistant Acinetobacter baumannii (CRAB) as an important nosocomial pathogen has caused the global antimicrobial resistance (AMR) crisis. CRAB is highly resistant due to its multidrug resistance, robust biofilm formation, and persistence in hospital environments, leading to severe infections with limited treatment options. Bacteriophage therapy may be a promising alternative due to its host specificity, self-amplification at infection sites, and potential to disrupt biofilms, overcoming key resistance mechanisms. The present study aims to isolate and characterise bacteriophages with antimicrobial and antibiofilm activity against CRAB. The therapeutic potential of selected tail proteins of isolated phage, specifically those involved in the interaction with bacterial host proteins, will be validated in-vitro and in-vivo, enabling the development of targeted, protein-based alternative therapeutics against CRAB. (2) Scientific objectives: • Isolation and characterisation of bacteriophages targeting CRAB, and analysis of molecular mechanisms of its lytic activity and host range. • Genetic and structural characterisation of isolated bacteriophages to elucidate infection mechanisms, host recognition, modulation of host gene expression, and adaptability. • Evaluation of bacteriophage efficacy, including antibacterial activity, biofilm disruption, synergy with antibiotics, and validation in in-vitro and in-vivo models. • Characterisation of bacterial host receptor proteins involved in interaction with bacteriophage tail protein, to facilitate the development of targeted tail protein-based therapeutics against CRAB and its biofilm. (3) Hypothesis: We hypothesise that lytic bacteriophages isolated from environmental sources like sewage water, rivers, etc, will possess specific antimicrobial and antibiofilm activity against CRAB. Furthermore, their tail proteins will interact with bacterial receptor proteins, facilitating the design of targeted tail protein-based therapeutics against CRAB, which may overcome the limitations of whole-phage therapy and may help combat phage resistance. (4) Experiments/Methods: This study aims to isolate and characterise lytic bacteriophages and identify their tail fibre proteins targeting carbapenem-resistant Acinetobacter baumannii (CRAB). The phages will be evaluated for lytic activity, host range, and antibiofilm potential. Their efficacy will be assessed using electron microscopy (TEM, SEM), confocal imaging, and synergy assays with antibiotics. Whole-genome sequencing and bioinformatics analyses will be conducted to elucidate infection mechanisms and host specificity. Molecular docking and molecular dynamics simulations will help identify bacterial receptor proteins that interact with phage tail proteins. Selected tail fibre and receptor proteins will be cloned, expressed, and purified, followed by biophysical interaction studies (e.g., CD, BLI, ITC etc.) to validate their binding. Design of targeted tail protein-based therapeutics with antibiotic conjugation. Finally, in-vitro (A549 cells) and in-vivo (Galleria mellonella) models will be used to evaluate therapeutic efficacy and bacterial clearance. (5): Significance to the field of research CRAB represents a critical global AMR threat, with limited treatment options. This study aims to develop potent tail protein-based therapeutics derived from lytic bacteriophage, offering a targeted and innovative alternative to conventional antibiotics for combating CRAB infections and addressing the growing AMR crisis. (6)Application: This study aims to develop tail protein-based therapeutics from lytic bacteriophages targeting CRAB. Insights into bacterial receptor interaction, biofilm inhibition, and specificity will support targeted alternatives to antibiotics and help combat antimicrobial resistance.