Biofilm Formation and Detection of pslÁ Gene in Multidrug Resistant Pseudomonas aeruginosa Isolated from Thi-Qar, Iraq

Abstract

Pseudomonas aeruginosa is considered as one of the major causes of hospital-acquired infections due to its high antibacterial resistance. Biofilm formation is a well-known pathogenic mechanism in P. aeruginosa infections. The detection of polysaccharide pslÁ gene can be important for biofilm formation by this bacteria. Therefore; A total of 96 swab sample were collected from burn and otitis infections at the two hospitals in THi_Qar province, Iraq, there were just 93 samples gave positive growth. By differential and selective media(McChonky agar,Cetrimide agar at 44oC, King A agar), biochemical tests(gram staining, oxidase, triple sugar iron agar and others) and growth at 42oC to detection and diagnosis the isolates as Pseudomonas species, followed by APi 20E assay supported by genotypic determined of 16S rRNA which proved there were 37(39.7%) identical isolates as P. aeruginosa. Antibiograms susceptibility test was performed via agar disk diffusion method were isolates subjected to 12 different items of antibiotics appeared that 12 and 4 isolates were multidrug resistant of burns and otitis respectively, with 3 isolates were pan-drugs resistance from burns. The ability of producing biofilm was examined by two phenotypic methods were Congo Red Agar and Crystal Violet Microtiter Plate Assay, the results showed that 32/37 (86.49%) isolates were slim adhesion formed in Congo red test, also there were 31/37 (83.78%) isolates produced biofilm formation, there were 43.47% and 21.42% strong biofilm formation from burns and otitis respectively by second method, all strong biofilm formation isolates were multidrugs resistance isolates. The detection and prevalence of the pslÁ genes among the isolates was determined by conventional monoplex polymerase chain reaction (PCR), the outcome exhibited that 34/37(91.89%) isolates carriage the pslÁ gene, also one and two from burns and otitis isolates respectively didn't carry this gene. The recent report is the first study with biofilm pslÁ gene in Iraq, and concluded that pslÁ gene harbored in most P.aeruginosa isolates even strong, moderate and weak biofilm but in different grade that mean there are another genes can contribute in biofilm synthesis must be investigated.