Molecular study of some virulence genes of Pseudomonas aeruginosa isolated from different infections in hospitals of Baghdad

In this study, two types of methods were used in the detection of biofilm formation: the first one was Congo red agar method and the second one was microtiter plate method. In the first method, results showed that biofilm formed by 57/100 (57%) according to black color production on media, whereas in the second method was 69/100 (69%) produce strong adherence according to OD in ELISA reader. Genotypic detection of many virulence factors related to P. aeruginosa was performed using conventional PCR. These included: gene coded for exoenzyme S (exoS), exoenzyme U (exoU), exotoxin A (toxA), two phospholipases C encoded by (plcH) and (plcN), alginate (algD), (lasB), rpsl, proteaseIV, and Neuraminidase (nan1). The results revealed that the most frequent gene was exoS as it was detected in 87/100 (87%) isolates, whereas the least frequent gene was nan1 as it was detected in only 9/100 (9%). The frequency of detection of other genes were as follows: toxAi in 55/100 (55%); plcH in 45/100 (45%); exoU in 42/100 (42%); plcN in 33/100 (33%); proteaseIV in 31/100 (31%), algD in 29/100 (29%); lasB in 28/100 (28%), and rpsl in 25/100 (25%). Phylogenetic analysis by Enterobacterial Repetitive Intergenic Consensus (ERIC-PCR), ERIC-DNA Fingerprinting revealed the diversity of all isolates in Baghdad by using Dice coefficient and the unweighted pair group method with arthmetic average (group method) of phylogenetic analysis. The percentage level of similarity clearly showed that the isolates exa...
Source: Reviews in Medical Microbiology - Category: Microbiology Tags: BACTERIOLOGY Source Type: research