Full-text

Available from: Dr. Arijit Das, Jun 15, 2015
0 Followers
 · 
225 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Objective: To isolate. Screen and characterize an effective phage for MDR and ESBL producing pathogenic bacterial strains. Methods: Bacteriophages were isolated from hospital effluent samples by double layer agar method. Isolated phages were propagated by liquid enrichment technique and its host range was analyzed by double layer agar method. Morphology of the isolated phages was identified by Transmission Electron Microscope (TEM). Genomic and proteomic analysis was confirmed by electrophoresis technique. Results & Discussion: 46 bacteriophages were isolated against 20 different MDR and ESBL strains of those 7 phages (Mm81, Ec84, Ps85, En833, Sal836, Ec8ATCC and Ec8PMG) were selected for further studies. According to the host range analysis result the 7 phage has been shown narrow host range. The phage genomic DNA and structural proteins were analyzed. In addition to based on the TEM analysis two phages viz., Mm81 and Ec84 were belongs to Siphoviridae and Podoviridae family respectively. Present study evaluates the extensive occurrence of phages in the hospital effluent. In addition, this is first report of isolation and characterization of Morganella morganii lytic phage in Tamil Nadu, India. Conclusion: The study highlights the distribution of bacteriophages in the hospital effluent and it gives the therapeutic potential of isolated phages for the treatment of MDR and ESBL Producing Pathogens.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Bacterial blight disease caused by Pseudomonas syringae pv. glycinea becomes one among several important factors that affects soybean production. To control this pathogen, most farmers apply synthetic pesticides that have negative effect for human, animal, and environment. Therefore, an alternative control must be developed including the use of bacteriophages. Moreover, identification and detection of this pathogen should be accurate for optimal diseases management. On the other hand, bacteriophage, a virus that infects specific host-bacterium, is largely known to have the ability to kill their specific host- bacterium. In addition, bacteriophage is also used as diagnostic tool for bacterial detection and identification of purpose, known as phatovar classification. This research was aimed to isolate the bacterial blight pathogen and their bacteriophage from soybean field in Jember, determine the pathogen pathogenicity and virulence, and determine the host-range of bacteriophage that infects several isolates of bacterial blight pathogen on soybean. The results has shown that among 12 isolates of bacterial blight pathogens that had similar characteristic to P. syringae pv. glycinea, only 10 isolates showed positive hypersensitive response (HR) on tobacco leaf. However, all isolates were virulent when inoculated to soybean leaves by showing particular bacterial blight symptom. In addition, one bacteriophage was found to infect isolate H3, called ϕPSGH3, and was to have 6 hosts among 12 bacterial isolates including isolates H3, SK4-2, BT4-1, KR1-1, KR4-2 dan MG4-1. The results from plaque assay PSGH3 with ϕH3-1 found out three only particle bacteriophage which are ϕGH1, ϕGH2 and ϕGH3.
    12/2014; 20:760-766. DOI:10.1016/j.proenv.2014.03.091
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: There has been an alarming increase in drug-resistant strains of diarrheagenic Escherichia coli (DEC) in developing as well as developed countries. Several cases of antimicrobial resistance in DEC have been observed in different parts of the world as a result, there has been a renewed interest in alternative antimicrobial treatments, including bacteriophages. This study was conducted to isolation and characterization of a lytic coliphage from sewage water capable to infect a variety of multidrug resistance DEC strains isolated from children suffering diarrhea, as first step to further usage a lytic coliphage in future.in this study, a coliphage was isolated using spotting method and titrated, using agar overlay technique. The host range of coliphages was assessed on a lawn of E coli bacteria. This study included determination of the latent periods and burst size of coli phage then determines the stability of coliphages to physical and chemical condition (temperature, pH and sunlight exposure).The results shown that, five phages isolate (A, B, C, D and E) were exhibiting a potent lytic activity with clear plaques (1-4mm in diameter). Fifty percent of the E coli strains were infected by phage isolates. It seems, very likely, that the coliphages belonging to 3 different groups (1, 2 and3). The phage growth cycle with a detected latent period of 20 min, a burst size of 160 plaque forming units per infected cell, it was found that the phage could survive at varied pH conditions with reduction in its numbers. A temperature of above 60°C and direct sunlight beyond 8 days was found to be deleterious for survival of the phage. 1. Introduction Bacterial viruses, known as bacteriophages or phages (from the Greek phagein, 'to eat') (Carter and Saunders, 2007) Bacteriophages are bacterial viruses that only infect and multiply within their specific hosts. Host specificity is generally found at strain and, species level, or, more rarely, at genus level. This specificity allows for directed targeting of dangerous bacteria using phages. Bacteriophages are the most numerous form of life on Earth; ten times more numerous than bacteria (Hagens and Loessner, 2010). They can be found in all the environments where bacteria grow: in the desert, hot springs, the North Sea, and polar inland waters (Jończyk et al., 2011; Sundar et al., 2009). These phages are important in order to regulate bacterial abundance and its distribution (Carter and Saunders, 2007). Bacteriophages that infect E. coil sometimes are referred generally as coli phage. In other words, coliphage can replicate only within coliform cells. Phage must attach to a receptor on the surface of a bacterial cell in order to initiate an infection. This interaction between the phage and receptor is very specific. a given phase type only will bind to a specific receptor molecule. Thus, all phage are not alike (Al-Mola and Al-Yassari, 2010). Two functional types of coliphages exist in the environment: male-specific (F+) and somatic coliphages. F+ coliphages infect their bacterial hosts by attachment to the F-pilus of the cell. Therefore, F+ coliphages only infect hosts that contain the F+ plasmid and can produce F-pili. Somatic coliphages infect bacterial hosts by direct attachment to cell walls. Coliphages have been suggested as indicators for the presence of enteric viruses in water because they have similar physiologically characteristics to some human enteric viruses, and are often found in the intestinal tract of humans and animals (Rodrígueza et al., 2012).They classified into five families: Myoviridae, Siphoviridae, Podoviridae and Microviridae. All families are found in the sewage, although Myoviridae and Siphoviridae are the most abundant (Muniesa et al., 2003). The sensitivity of a host strain to a particular bacteriophage is usually measured by the diameter of the lytic zone around the spot of a small volume of phages suspension onto a lawn of host bacteria. The size of this zone indicates sensitivity of the host bacteria to the tested bacteriophage (Adams, 1959) (Muniesa et al., 2003).