Pseudomonas aeruginosa, a ubiquitous environmental organism, is a difficult-to-treat opportunistic pathogen due to its broad-spectrum antibiotic resistance and its ability to form biofilms. In this study, we investigate the link between resistance to a clinically important antibiotic, imipenem, and biofilm formation. First, we observed that the laboratory strain P. aeruginosa PAO1 carrying a mutation in the oprD gene, which confers resistance to imipenem, showed a modest reduction in biofilm formation.We also observed an inverse relationship between imipenem resistance and biofilm formation for imipenem-resistant strains selected in vitro, as well as for clinical isolates.We identified two clinical isolates of P. aeruginosa from the sputum
... Show MoreOwing to high antibacterial resistance of Pseudomonas aeruginosa, it could be considered as the main reason behind the nosocomial infections. P. aeruginosa has a well-known biofilm forming ability. The expression of polysaccharide encoding locus (pelA gene) by P. aeruginosa is essential for this ability. The purpose of the current research was to determine the biofilm formation in P. aeruginosa isolated from clinical samples and to evaluate the role of the selected PelA gene in biofilm formation using PCR method in Iraqi patients. Results revealed that 24 (96%) isolates were found to have the ability to form biofilm that was remarkably related to gentamicin resistance. Moreover, the pelA gene was found in all biofilm-producers. In c
... Show MoreOne of the most important virulence factors in Pseudomonas aeruginosa is biofilm formation, as it works as a barrier for entering antibiotics into the bacterial cell. Different environmental and nutritional conditions were used to optimize biofilm formation using microtitre plate assay by P. aeruginosa. The low nutrient level of the medium represented by tryptic soy broth (TSB) was better in biofilm formation than the high nutrient level of the medium with Luria Broth (LB). The optimized condition for biofilm production at room temperature (25 °C) is better than at host temperature (37 °C). Moreover, the staining with 0.1% crystal violet and reading the biofilm with wavelength 360 are considered essential factors in
... Show MoreThe aim of this research is to evaluate the effect of glucose and sodium chloride on biofilm formation by bacteria causing wound infection. For this purpose, 1% and 2% concentration of each of glucose and sodium chloride were used to test the biofilm formation potential of Staphylococcus aureus and Pseudomonas aeruginosa, which were the most common abundant bacteria that cause infection by biofilm. Each of the concentrations was kept in contact with the pathogenic bacteria for 24 hours. After the period of incubation, the concentration of 1% of glucose enhanced moderate biofilm formation capacity for (66% and 80%) on both bacteria respectively. The concentration of 2% glucose, on the other hand, led to a weak biofilm fo
... Show MoreTen isolates of Klebsiella pneumoniae, seven isolates of Pseudomonas aeruginosa and nine isolates of Staphylococcus aureus, were obtained from 100 urine samples collected from Baghdad hospitals. All isolates were identified biochemically and confirmed by using VITEK 2 and were then tested for their susceptibility towards 6 antibiotics and for phenolic extracts of Thymus vulgaris and Cinnamomum cassia. All bacteria were greatly affected by T. vulgaris, especially K. pneumoniae. Viable count was performed, it was noted that the number of bacterial cells reduced from 1×108 CFU to 1.2× 103, 2×105 and 1.8×106CFU of K. pneumoniae, P. aeruginosa and S. aureus respectively. While C. cassiahad a slight effect on them. K. pneumoniae isola
... Show MorePvcABCD are cluster of genes found in Pseudomonas aeruginosa. The research was designed to examine the relationship between the pvc genes expression and cupB gene, which plays a crucial role in the development of biofilm, and rhlR, which regulates the expression of biofilm-related genes, and to investigate whether the pvc genes form one or two operons. The aims were achieved by employing qRT-PCR technique to measure the gene expression of genes of interest. It was found that out of 25 clinical isolates, 21 isolates were qualified as P.aeruginosa. Amongst, 18(85.7%) were evaluated as biofilm producers, 10 (47.6%), 5 (23.8%), and 3 (14.2%) were evaluated as strong, moderate and weak producers respectively, while, 3 (14.2%) were considered
... Show MoreThree isolates of P. aeruginosa were isolated from burnt patients. The ability of these isolates for adhesion and formation of slime layer were tested, the result showed that all isolates were able to adherence on the smooth surface. The sensitivity of P. aeruginosa isolates for antibiotics were tested , all isolates were sensitive to Gentamycin, Piperacillin and Amikacin Ciprofloxacin, and resist to Tetracyclin, Amoxicillin, Cephalexine , Ceftriaxone. Ciprofloxacin and Amikacin were found effective against P. aeruginosa isolates with MIC values of 3.8 μg/ ml for Ciprofloxacin and 0.244 μg/ ml for Amikacin The antibacterial effect of Different concentrations of Aloe
... Show MoreBacteria form complex and highly elaborate surface adherent communities known as biofilms.Biofilm have been shown to be associated with several human diseases ,and to colonize a wide variety of medical devices . The current study focuses on contribution of extracted genomic DNA in biofilm formation by P. aeruginosa and K. pneumoniae isolates .The percentages of Pseudomonas aeruginosa recovery from drinking water in this study were 10%(20 positive P. aeruginosa samples ) and K. pneumonia., 7%(14 positive K. pneumonia samples).The results showed that all P.aeruginosa and K. pneumoniae isolates (100%) were slime producer but in different degrees by forming of black
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