医学微生物学与诊断

Isolation and Characterization of Pseudomonas aeruginosa and Its Virulent Bacteriophages

Abstract

Eman M. Marie

Pseudomonas aeruginosa is a free-living bacterium in widely different areas such as plants, soil, water and other moist locations. It is pathogenic to plants and humans. P. aeruginosa causes several disease symptoms to plants such as wet rot and curved leaves. The virulent bacterial viruses of P. aeruginosa were found to be of widespread occurrence in nature and isolated from widely different sources. Bacterial viruses were applied to control pathogenic bacteria in different fields and successfully. Therefore, this work aimed to study the different characteristics of P. aeruginosa lytic phage isolates. Moreover, the biocontrol of P. aeruginosa by lytic phage isolates was also studied. Different physical and molecular characteristics were assayed and determined of P. aeruginosa lytic bacteriophages. Also, the effect of phage isolates on P. aeruginosa as a biocontrol under lab condition was studied. 
Pseudomonas aeruginosa pathogenic bacterium was isolated from a sewage water sample. Two lytic bacteriophages specific to P. aeruginosa were isolated from same sewage water sample and designated Pa1 and Pa2. Both phage isolates (Pa1 and Pa2) found to be stable in 90ºC and low and high pH levels. The total count of P. aeruginosa decreased after 48h. in broth treated with lytic phages. RAPD-PCR amplification was indicated that the two phage isolates (Pa1 and Pa2) are belonging to two different phage types. 
The results of this study indicated that both lytic phage isolates could be used as biological control agents against the plant pathogen P. aeuroginosa.