The treatment of Acinetobacter baumannii(A.baumannii)poses significant clinical challenges due to its multidrug/pan-drug resistance.In this study,we isolated a broad-spectrum lytic A.baumannii phage,named P425,from me...The treatment of Acinetobacter baumannii(A.baumannii)poses significant clinical challenges due to its multidrug/pan-drug resistance.In this study,we isolated a broad-spectrum lytic A.baumannii phage,named P425,from medical wastewater,targeting nine multidrug-resistant A.baumannii(MDRAB)with diverse capsular types.Biological characterization revealed that P425 maintains activity at pH range of 3–12 and temperature range of 4–50℃.It resists UV irradiation for 20 minutes,and had an optimal multiplicity of infection(OMOI)is 0.00001.The adsorption kinetics showed that P425 achieves>90%within 10 minutes of incubation,and the one-step growth curve indicated a 10-min latent period,with a burst size of 184 PFU/cell.The genome sequencing results indicated that it harbors a double-stranded DNA genome of 40,583 bp with a GC content of 39.39%.Intergenomic similarity analysis classified it as a novel species within the Friunavirus genus,while electron microscopy results showed that it belongs to the Podoviridae family.Notably,P425 exhibits potent 24-h in vitro inhibitory activity against MDRAB,and demonstrates synergistic effect at an MOI of 0.001 when combined with five classes of antibiotics targeting distinct antimicrobial mechanisms.Safety evaluations confirmed the absence of cytotoxicity,hemolytic activity,or systemic toxicity both in vitro and in vivo.In mouse infection models,P425 can significantly improve the survival rates of mice infected with Ab25(ST1791/KL101).When co-administered with levofloxacin,it achieved 100%protection against mortality and promoted immune recovery.Collectively,P425 is a prospective lytic phage that could offer novel strategies for combating MDRAB infections.展开更多
基金supported by the Nanjing Infectious Disease Clinical Medical Center,Innovation center for infectious disease of Jiangsu Province(NO.CXZX202232)the Leading Talent Project of Jiangsu Province Traditional Chinese Medicine(NO.SLJ0216)+4 种基金the Nanjing Health science and Technology Development Special fund Project(NO.YKK20102)the General Program of Jiangsu Commission of Health(NO.M2021088)the Nanjing Health science and Technology Development General Project(NO.YKK21121)the 2023 Nanjing Second Hospital Talent Support Project Grant(RCZD23003)the Jiangsu Province Postgraduate Research and Practice Innovation Program(KYCX24_2176).
文摘The treatment of Acinetobacter baumannii(A.baumannii)poses significant clinical challenges due to its multidrug/pan-drug resistance.In this study,we isolated a broad-spectrum lytic A.baumannii phage,named P425,from medical wastewater,targeting nine multidrug-resistant A.baumannii(MDRAB)with diverse capsular types.Biological characterization revealed that P425 maintains activity at pH range of 3–12 and temperature range of 4–50℃.It resists UV irradiation for 20 minutes,and had an optimal multiplicity of infection(OMOI)is 0.00001.The adsorption kinetics showed that P425 achieves>90%within 10 minutes of incubation,and the one-step growth curve indicated a 10-min latent period,with a burst size of 184 PFU/cell.The genome sequencing results indicated that it harbors a double-stranded DNA genome of 40,583 bp with a GC content of 39.39%.Intergenomic similarity analysis classified it as a novel species within the Friunavirus genus,while electron microscopy results showed that it belongs to the Podoviridae family.Notably,P425 exhibits potent 24-h in vitro inhibitory activity against MDRAB,and demonstrates synergistic effect at an MOI of 0.001 when combined with five classes of antibiotics targeting distinct antimicrobial mechanisms.Safety evaluations confirmed the absence of cytotoxicity,hemolytic activity,or systemic toxicity both in vitro and in vivo.In mouse infection models,P425 can significantly improve the survival rates of mice infected with Ab25(ST1791/KL101).When co-administered with levofloxacin,it achieved 100%protection against mortality and promoted immune recovery.Collectively,P425 is a prospective lytic phage that could offer novel strategies for combating MDRAB infections.
