Isolation and characterization of wide host range lytic bacteriophage AP22 infecting Acinetobacter baumannii
Anastasia V Popova1, Evgeny L Zhilenkov, Vera P Myakinina
1State Research Center for Applied Microbiology & Biotechnology, Obolensk, Russia.
Abstract:
Acinetobacter baumannii plays a significant role in infecting patients admitted to hospitals. Many A. baumannii infections, including ventilation-associated pneumonia, wound, and bloodstream infections, are common for intensive care and burn units. The ability of the microorganism to acquire resistance to many antibiotics, disinfectants, and dehydration assures its long-term survival in hospital settings. The application of bacteriophages is a potential tool to control A. baumannii infections. Bacteriophage AP22 lytic for A. baumannii was isolated from clinical materials and classified as a member of the Myoviridae family. The phage had an icosahedral head of 64 nm in diameter and a contractile tail of 85-90 nm in length. According to restriction analysis, AP22 had 46-kb double-stranded DNA genome. The phage AP22 exhibited rapid adsorption (> 99% adsorbed in 5 min), a large burst size (240 PFU per cell), and stability to the wide range of pH. The bacteriophage was shown to specifically infect and lyse 68% (89 of 130) genotype-varying multidrug-resistant clinical A. baumannii strains by forming clear zones. Thus, it could be used as a candidate for making up phage cocktails to control A. baumannii-associated nosocomial infections.
Insights
Bacteriophage AP22 effectively targets multidrug-resistant Acinetobacter baumannii, a common hospital pathogen. This lytic phage shows promise for developing phage cocktails to combat nosocomial infections.
Area of Science:
- Microbiology
- Virology
- Infectious Diseases
Background:
- Acinetobacter baumannii is a significant cause of hospital-acquired infections, particularly in intensive care units.
- Its multidrug resistance and survival capabilities make it a persistent threat in healthcare settings.
- Bacteriophages offer a potential alternative for controlling A. baumannii infections.
Purpose of the Study:
- To isolate and characterize a bacteriophage effective against Acinetobacter baumannii.
- To evaluate the potential of bacteriophage AP22 as a therapeutic agent against multidrug-resistant strains.
Main Methods:
- Isolation and classification of bacteriophage AP22 from clinical samples.
- Morphological and genomic characterization of the phage.
- Assessment of adsorption, burst size, stability, and lytic activity against clinical A. baumannii isolates.
Main Results:
- Bacteriophage AP22, a Myoviridae family member, possesses an icosahedral head and contractile tail with a 46-kb dsDNA genome.
- AP22 demonstrated rapid adsorption, a high burst size (240 PFU/cell), and stability across a wide pH range.
- The phage effectively lysed 68% of multidrug-resistant clinical A. baumannii strains, forming clear zones.
Conclusions:
- Bacteriophage AP22 is a potent lytic agent against multidrug-resistant Acinetobacter baumannii.
- Its characteristics suggest it is a strong candidate for inclusion in phage cocktails for managing nosocomial infections.
