Isolation, characterization, therapeutic potential and depolymerase identification of a lytic bacteriophage Kpp-9 against Klebsiella pneumoniae with capsule serotype K2.
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引用次数: 0
Abstract
Klebsiella pneumoniae is one of the most threatening multidrug-resistant bacteria, and its inherent capsule and extensive biofilm formation pose a significant barrier to the treatment of infection. Bacteriophages (or phages) and phage-derived depolymerases are attracting attention as potential alternatives to antibiotics. Here, we isolated a lytic phage, named Kpp-9, using a capsule-type K2 strain, Kp09. Kpp-9 could inhibit bacterial biofilm formation, eradicate the mature biofilm in vitro, improve the survival rate of Kp09-infected mice, and alleviate the symptoms of pneumonia in mice. Morphological and genomic analyses showed that phage Kpp-9 belonged to the class Caudoviricetes and no virulence or resistance genes were found in the genome, indicating potential therapeutic applications of phage Kpp-9. Furthermore, two depolymerases (Kp9042 and Kp9050) were predicted and shown to be able to digest the capsule and improve the susceptibility of K. pneumoniae to complement-mediated serum killing. In addition, Kpp-9 and two depolymerases showed high selectivity for capsule-type K2 K. pneumoniae strains and exhibited robust thermal and pH stability. These results demonstrate that phage Kpp-9 and its encoded depolymerases Kp9042 and Kp9050 may serve as alternative therapeutic agents for the treatment of capsule-type K2 K. pneumoniae infections.
期刊介绍:
Microbial Pathogenesis publishes original contributions and reviews about the molecular and cellular mechanisms of infectious diseases. It covers microbiology, host-pathogen interaction and immunology related to infectious agents, including bacteria, fungi, viruses and protozoa. It also accepts papers in the field of clinical microbiology, with the exception of case reports.
Research Areas Include:
-Pathogenesis
-Virulence factors
-Host susceptibility or resistance
-Immune mechanisms
-Identification, cloning and sequencing of relevant genes
-Genetic studies
-Viruses, prokaryotic organisms and protozoa
-Microbiota
-Systems biology related to infectious diseases
-Targets for vaccine design (pre-clinical studies)