Klebsiella pneumoniae (family Enterobacteriaceae) is a gram-negative bacterium that has strong pathogenicity to humans and can cause sepsis, pneumonia, and urinary tract infection. In recent years, the unreasonable use of antibacterial drugs has led to an increase in drug-resistant strains of K. pneumoniae, a serious threat to public health. Bacteriophages, viruses that infect bacteria, are ubiquitous in the natural environment. They are considered to be the most promising substitute for antibiotics because of their high specificity, high efficiency, high safety, low cost, and short development cycle. In this study, a novel phage designated vB_KpnP_IME279 was successfully isolated from hospital sewage using a multidrug-resistant strain of K. pneumoniae as an indicator. A one-step growth curve showed that vB_KpnP_IME279 has a burst size of 140 plaque-forming units/cell and a latent period of 20 min at its optimal multiplicity of infection (MOI = 0.1). Phage vB_KpnP_IME279 survives in a wide pH range between 3 and 11 and is stable at temperatures ranging from 40 to 60 °C. Ten of the 20 strains of K. pneumoniae including the host bacteria were lysed by the phage vB_KpnP_IME279, and the multilocus sequence typing and wzi typing of the 10 strains were ST11, ST37, ST375, wzi209, wzi52, and wzi72, respectively. The genome of vB_KpnP_IME279 is 42,518 bp long with a G + C content of 59.3%. Electron microscopic observation showed that the phage belongs to the family Podoviridae. BLASTN alignment showed that the genome of the phage has low similarity with currently known phages. The evolutionary relationship between phage vB_KpnP_IME279 and other Podoviridae was analyzed using a phylogenetic tree based on sequences of phage major capsid protein and indicates that the phage vB_KpnP_IME279 belongs to the Podoviridae subfamily. These data enhance understanding of K. pneumoniae phages and will help in development of treatments for multidrug-resistant bacteria using phages.
- MeSH
- antibakteriální látky farmakologie MeSH
- bakteriofágy klasifikace genetika izolace a purifikace fyziologie MeSH
- fylogeneze MeSH
- genom virový MeSH
- hostitelská specificita MeSH
- Klebsiella pneumoniae účinky léků izolace a purifikace virologie MeSH
- lidé MeSH
- mikrobiologické techniky MeSH
- mnohočetná bakteriální léková rezistence MeSH
- multilokusová sekvenční typizace MeSH
- nemocnice MeSH
- odpadní vody mikrobiologie virologie MeSH
- Podoviridae klasifikace genetika izolace a purifikace MeSH
- RNA ribozomální 16S MeSH
- sekvenování celého genomu MeSH
- techniky typizace bakterií MeSH
- teplota MeSH
- zastoupení bazí MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Biofilm is involved in a variety of infections, playing a critical role in the chronicity of infections. Enterobacter cloacae is a biofilm-forming and multi-drug-resistant (MDR) nosocomial pathogen leading to significant morbidity and mortality. This study aimed at isolation of a bacteriophage against MDR clinical strain of E. cloacae and its efficacy against bacterial planktonic cells and biofilm. A bacteriophage MJ2 was successfully isolated from wastewater and was characterized. The phage exhibited a wide range of thermal and pH stability and demonstrated considerable adsorption to host bacteria in the presence of CaCl2 or MgCl2. Transmission electron microscopy (TEM) showed MJ2 head as approximately 62 and 54 nm width and length, respectively. It had a short non-contractile tail and was characterized as a member of the family Podoviridae [order Caudovirales]. The phage MJ2 was found to possess 11 structural proteins (12-150 kDa) and a double-stranded DNA genome with an approximate size of 40 kb. The log-phase growth of E. cloacae both in biofilm and suspension was significantly reduced by the phage. The E. cloacae biofilm was formed under different conditions to evaluate the efficacy of MJ2 phage. Variable reduction pattern of E. cloacae biofilm was observed while treating it for 4 h with MJ2, i.e., biofilm under static conditions. The renewed media with intervals of 24, 72, and 120 h showed biomass decline of 2.8-, 3-, and 3.5-log, respectively. Whereas, the bacterial biofilm formed with dynamic conditions with refreshing media after 24, 72, and 120 h demonstrated decline in growth at 2.5-, 2.6-, and 3.3-log, respectively. It was, therefore, concluded that phage MJ2 possessed considerable inhibitory effects on MDR E. cloacae both in planktonic and biofilm forms.
- MeSH
- biofilmy růst a vývoj MeSH
- chlorid hořečnatý farmakologie MeSH
- chlorid vápenatý farmakologie MeSH
- délka genomu MeSH
- DNA virů MeSH
- Enterobacter cloacae virologie MeSH
- genom virový genetika MeSH
- hostitelská specificita MeSH
- koncentrace vodíkových iontů MeSH
- mikrobiální viabilita MeSH
- mnohočetná bakteriální léková rezistence * MeSH
- molekulová hmotnost MeSH
- odpadní voda virologie MeSH
- Podoviridae izolace a purifikace fyziologie ultrastruktura MeSH
- přichycení viru účinky léků MeSH
- teplota MeSH
- virové proteiny chemie MeSH
- Publikační typ
- časopisecké články MeSH
Pseudomonas aeruginosa is an opportunistic pathogen that causes serious infections, especially in patients with immunodeficiency. It exhibits multiple mechanisms of resistance, including efflux pumps, antibiotic modifying enzymes and limited membrane permeability. The primary reason for the development of novel therapeutics for P. aeruginosa infections is the declining efficacy of conventional antibiotic therapy. These clinical problems caused a revitalization of interest in bacteriophages, which are highly specific and have very effective antibacterial activity as well as several other advantages over traditional antimicrobial agents. Above all, so far, no serious or irreversible side effects of phage therapy have been described. Five newly purified P. aeruginosa phages named vB_PaeM_WP1, vB_PaeM_WP2, vB_PaeM_WP3, vB_PaeM_WP4 and vB_PaeP_WP5 have been characterized as potential candidates for use in phage therapy. They are representatives of the Myoviridae and Podoviridae families. Their host range, genome size, structural proteins and stability in various physical and chemical conditions were tested. The results of these preliminary investigations indicate that the newly isolated bacteriophages may be considered for use in phagotherapy.
- MeSH
- bakteriofágy klasifikace genetika izolace a purifikace fyziologie MeSH
- biologická terapie MeSH
- hostitelská specificita MeSH
- lidé MeSH
- molekulární sekvence - údaje MeSH
- Myoviridae klasifikace genetika izolace a purifikace fyziologie MeSH
- odpadní vody virologie MeSH
- Podoviridae klasifikace genetika izolace a purifikace fyziologie MeSH
- pseudomonádové infekce mikrobiologie terapie MeSH
- Pseudomonas aeruginosa virologie MeSH
- virové proteiny genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
