Isolation and Characterization of a Novel Myophage Abp9 Against Pandrug Resistant Acinetobacater baumannii

Abstract

Acinetobacter baumannii (A. baumannii) has emerged as one of the most troublesome pathogens in health care institutions. A. baumannii can cause a wide range of diseases in humans, including pneumonia and septicemia. Phage therapy has drawn great interest from medical researchers as a potential way to control infections by antibioticresistant A. baumannii. Using a pandrug-resistant clinical A. baumannii isolate AB ZY 9 as an indicator, we isolated a lytic phage Abp9 from hospital sewage. Abp9 belongs to myoviridae family and shows a wider host range of 12%. Abp9 contains a linear double-stranded DNA genome of 44,820 bp with a G + C content of 37.69%. The Abp9 genome contains 80 open reading frames, but lacks any known virulence genes or lysogen-formation genes. In a systemic A. baumannii infection mouse models, Abp9 treatment showed good therapeutic effects. We have also observed an excellent lytic activity against A. baumannii in biofilm form of growth in vitro. All of these suggest that Abp9 is a good candidate for the phage therapy against drug-resistant A. baumannii infections.

Animal Models in the Evaluation of the Effectiveness of Phage Therapy for Infections Caused by Gram-Negative Bacteria from the ESKAPE Group and the Reliability of Its Use in Humans

“…Studies in murine models are particularly often described, including in the case of bacterial infections and phage therapy used against them. Many different routes of administration of bacteriophages or their enzymes can be used in mice, for example, intranasally or intratracheally in the case of pneumonia [54,[57][58][59][60], intraperitoneally or intramuscularly in the case of sepsis [55,[61][62][63], intraperitoneally or/and topically in the case of wound infection [59,64], by injection into subcutaneous pockets in the case of a wound infection sustained during catheterization [65], and topically to the corneal surface in the cases of eye infections [66,67]. The advantages and disadvantages of different routes of phages or phage enzyme administration are presented in Table 1.…”

“…A mouse model of systemic infection caused by A. baumannii and the applied phage therapy was described by Jiang et al [61]. Immediately after intraperitoneal administration of bacterial suspension, mice were injected with the first dose of the bacteriophage suspension (5.0 × 10 8 PFU) by the same route.…”

Bacteriophage therapeutics to confront multidrug‐resistant Acinetobacter baumannii ‐ a global health menace

“…(2016) suggested that phage‐mediated eradication as well as disinfection of biofilms formed on metal surfaces is more difficult than that of biofilms in a liquid environment. The phage Abp9 effectively cleared ABZY9‐produced biofilms in vitro and in mice infection model reducing mortality in the latter (Jiang et al ., 2020).…”

“…Phage‐derived depolymerases have the unique ability to recognize and degrade capsule polysaccharides, EPS and O‐antigen and thus, present a promising tool in the therapeutics as well as diagnostics (Latka et al ., 2017). Depolymerases degrade components of the biofilm exopolymeric matrix enabling the phages to infect the inner cells of biofilms (Jiang et al ., 2020).…”

Characterization and Sequencing of a Novel Phage Abp95 Against Multi-genotypes of Carbapenem-resistant Acinetobacter Baumannii

“…In previous studies, we have successfully isolated podoviridae phage Abp1 from hospital sewage, and its treatment effect was tested in a local and system mouse model of infection [12]. Using a drug-resistant A. baumannii strain ABzy9 separate from a patient's femoral venous catheter, and we also isolated a myoviridae phage Abp9 that cleaves ABzy9 [13]. Abp9 can effectively remove the bio lm produced by ABzy9 and reduce the mortality rate of rats infected with ABzy9.…”