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Characterization of a Novel Phage ΦAb1656-2 and Its Endolysin with Higher Antimicrobial Activity against
Kyeongmin Kim1, Md Maidul Islam1, Dooyoung Kim1
1Department of Microbiology, School of Medicine, Kyungpook National University, 680 Gukchaebosang-ro, Jung-gu, Daegu 41944, Korea.
Abstract:
Acinetobacter baumannii is a nosocomial pathogen, which is a problem worldwide due to the emergence of a difficult-to-treat multidrug-resistant A. baumannii (MDRAB). Endolysins are hydrolytic enzymes produced by a bacteriophage that can be used as a potential therapeutic agent for multidrug-resistant bacterial infection in replacing antibiotics. Here, we isolated a novel bacteriophage through prophage induction using mitomycin C from clinical A. baumannii 1656-2. Morphologically, ΦAb1656-2 was identified as a Siphoviridae family bacteriophage, which can infect MDRAB. The whole genome of ΦAb1656-2 was sequenced, and it showed that it is 50.9 kb with a G + C content of 38.6% and 68 putative open reading frames (ORFs). A novel endolysin named AbEndolysin with an N-acetylmuramidase-containing catalytic domain was identified, expressed, and purified from ΦAb1656-2. Recombinant AbEndolysin showed significant antibacterial activity against MDRAB clinical strains without any outer membrane permeabilizer. These results suggest that AbEndolysin could represent a potential antimicrobial agent for treating MDRAB clinical isolates.
Insights
A novel bacteriophage, ΦAb1656-2, was isolated from multidrug-resistant Acinetobacter baumannii. Its endolysin, AbEndolysin, demonstrated significant antibacterial activity against resistant strains, offering a potential new therapeutic agent.
Area of Science:
- Microbiology
- Molecular Biology
- Biochemistry
Background:
- Acinetobacter baumannii is a global nosocomial pathogen.
- Multidrug-resistant Acinetobacter baumannii (MDRAB) poses a significant treatment challenge.
- Bacteriophage-derived endolysins are promising alternatives to antibiotics.
Purpose of the Study:
- To isolate and characterize a novel bacteriophage from MDRAB.
- To identify, express, and purify a novel endolysin from the isolated bacteriophage.
- To evaluate the antibacterial activity of the novel endolysin against MDRAB.
Main Methods:
- Isolation of bacteriophage ΦAb1656-2 from clinical MDRAB using mitomycin C-induced prophage.
- Morphological identification of ΦAb1656-2 as a Siphoviridae family member.
- Whole genome sequencing of ΦAb1656-2.
- Identification, expression, and purification of the novel endolysin AbEndolysin.
- Assessment of AbEndolysin's antibacterial activity against MDRAB clinical strains.
Main Results:
- A novel Siphoviridae bacteriophage, ΦAb1656-2, was successfully isolated.
- The whole genome of ΦAb1656-2 was sequenced (50.9 kb, 68 ORFs).
- A novel endolysin, AbEndolysin, with an N-acetylmuramidase catalytic domain was identified and purified.
- Recombinant AbEndolysin exhibited potent antibacterial activity against MDRAB clinical isolates without requiring outer membrane permeabilizers.
Conclusions:
- AbEndolysin is a potent antimicrobial agent effective against multidrug-resistant Acinetobacter baumannii.
- This novel endolysin shows potential as a therapeutic agent for treating MDRAB infections.
- Phage-derived endolysins represent a viable strategy to combat antibiotic resistance.
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