الفهرس | Only 14 pages are availabe for public view |
Abstract In this study, a total of 100 isolates of Ps. aeruginosa were isolated and identified, Imipenem could be considered the drug of choice for treatment of infections caused by multiresistant Ps. aeruginosa. In the present study, a simple and inexpensive testing method for screening of IMP producers was performed using thiol compounds (IMP inhibitors) including 2-mercaptoethanol, cupric chloride, ferric chloride and EDTA. For IMP producing strains, EDTA and 2-mercapto ethanol gave the clearest results. Plasmid profile is one of several useful methods for determining the relatedness or unrelatedness of bacterial strains that contain plasmid DNA. The most common and widespread acquired MBLs are those of the IMP and VIM types, which exhibit a world wide distribution and for which several allelic variants are known. Significant genetic variation was observed among different strains represented by the diversity of their plasmid profiles, Plasmid analysis is particularly important to determine the evolution and spread of antibiotic resistance among isolates. In the present study, both IMP and VIM genes could be successfully amplified by touch down PCR protocol as the markers encoding MBLs resistance. The specific well designed amplification primers for both markers could amplify 100% of both markers in genomic DNA extracted from the Ps. aeruginosa strains isolated from different clinical sources. This study focused on typing these two markers among the isolated strains. To find out the similarities and differences between them the generated amplicons were subjected to bidirectional Sanger’s method of sequencing using ABI3730 sequencer and determine the degree of relatedness between the isolates. In the present investigation, several mutations could be detected in the variable regions of the IMP and VIM genes in Ps. aeruginosa isolates. Neighbor-joining trees were constructed to analyze nucleotide sequence similarity and determine the relatedness between isolates. Sanger’s sequencing results of MBLs genes among Ps. aerugimosa isolates showed that IMP gene grouping them into 3 groups and VIM gene grouping them into 2 groups according to their similarities. |