The present work aimed to investigate the neuraminidase (nan1) gene expression in 32 different clinical isolates of Pseudomonas aeruginosa to explore the role of the enzyme in different types of infection and might give a better understanding of host cell-pathogens interaction. In addition, the effect of monosaccharide D-mannose on neuraminidase gene expression in eight isolates was studied by utilizing a reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The results demonstrated that the highest expression of nan1 gene was in otitis samples (208,913.81) which were significantly higher than that from other infections (P < 0.01). While, the concentrations of gene copies obtained from urine, sputum and burns samples were 93,535.34, 92,254.64 and 74,029.63respectively. While the least expression in wound samples (32,017.06). This suggests that neuraminidase in ear samples might be more virulent and invasive followed by that from urine, sputum, burns and wounds samples. The considerable interest of addition D-mannose significantly reduced the rate of neuraminidase activity reached fivefold in some isolates. This indicates that D-mannose down regulates nan1 gene expression. Hence, this sugar could be used in the development of potential new antibacterial agents where it acts as a competitive neuraminidase inhibitors.
The study was aimed at inhibiting the protease produced by Pseudomonas aeruginosa using an 80% alcoholic extract of Conocarpus lancifolius leaves. A total of 146 isolates of P. aeruginosa that were isolated and identified by microscopic and biochemical tests were 51 isolates submitted to primary and secondary screening techniques in order to choose the qualified P. aeruginosa isolate for protease synthesis. Among these isolates, forty-seven isolates showed hydrolysis zones on skim milk media (primary screening); six isolates were chosen for secondary screening. The result revealed that P. aeruginosa P51 had the highest ability to produce the enzyme, with a specific activity of 15.9 U/
... Show MorePseudomonas aeruginosa is the most common opportunistic pathogen causing morbidity and mortality in hospitalized patients due to its multiple resistance mechanisms. Therefore, as a therapeutic option becomes restricted, the search for a new agent is a preference. So P. aeruginosa is an extremely versatile Gram-negative bacterium capable of thriving in a broad spectrum of environments, and this performs main problems to workers in the field of health. One hundred and fifty samples were collected from different sources from Baghdad hospitals, divided into two main groups: clinical (100) specimens and (50) samples as an environmental, collected from October 2019 to the March 2020. All of these samples were cultured by specific and differential
... Show MoreThe present study aims to evaluate the synergistic activity of nicotinic acid (NIC) with the Imipenem (IMI) as an anti-biofilm for clinical isolated Pseudomonas aeruginosa. The values of minimum inhibitor concentration (MICs) for IMI and NIC (Separately) against P. aeruginosa were (16) ug/mL and (8) ug/ml respectively. Whereas, the concentration of NIC with IMI (as combined) for biofilm inhibition was 1 ug/ml for NIC and 4 ug/ml for IMI. The combining of NIC with IMI showed synergistic efficacy against formation of bacterial biofilm (at MIC levels). These results provide a conclusion that NIC combined with IMI is can be considered as a successful prospective treatment against the biofilm pr
... Show MoreThe pathogenicity resulting from Staphylococcus aureus infection has remarkable importance as one of the community-associated bacterial infections, due to the virulent ability of these bacteria to produce biofilms. This study was designed to detect biofilm production in clinical isolates from samples of wounds and urinary tract infections. The expression levels of the icaA gene that is responsible of slime layer production in biofilms was compared in isolates with different biofilm producing capabilities. Fifty seven samples that included 32 samples from urine and 25 samples from wounds were collected from Alwasti Hospital, Al-Kindi Teaching Hospital, and Alzahraa Clinic, Baghdad, Iraq. The bacteria was identified accor
... Show MorePseudomonas aeruginosa produces an extracellular bioï¬lm matrix that consists of nucleic acids, exopolysaccharides, lipid vesicles, and proteins. Alginate, Psl and Pel are three exopolysaccharides that constitute the main components in biofilm matrix, with many biological functions attributed to them, especially concerning the protection of the bacterial cell from antimicrobial agents and immune responses. A total of 25 gentamicin-resistant P. aeruginosa selected isolates were enrolled in this study. Biofilm development was observed in 96% of the isolates. In addition, the present results clarified the presence of pelA and pslA in all the studied isolates. The expression of these genes was very low. Even though all biof
... Show MoreSwarming is one of the most important virulence factors used by bacteria to invade new sites. This study aimed to test the effects of gentamicin on swarming motility of Pseudomonas aeruginosa, both phenotypically and molecularly. The present results revealed that 11/25 isolates had gentamicin MIC of 1024 µg/ml. However, gentamicin at sub-minimal inhibitory concentration significantly (P< 0.05) reduced the diameter of swarming in all P. aeruginosa isolates. Noticeably the mean and median swarming diameter before treatment with gentamicin 5.557 and 5.816 cm respectively had significantly (P < 0.001) reduced to 0.871 and 0.766 cm respectively. At the molecular level, amrZ (a global regulator
... Show MoreThe present study was conducted to investigate the resistance of fluoroquinolones (FQs) and the effects of mutations in the resistance gene in clinical isolates of P. aeruginosa isolated from different sources in Al-Hussein Hospital, Al-Samawah city, Iraq. The basic mechanism of the resistant of fluoroquinolones in P. aeruginosa is via mutations occurring in the basic bacterial gyrA gene encoding-subunit A of DNA gyrase . Forty clinical isolates from various sourced (burn 7 (17.5 %), wound 7 (17.5 %), ear 2 (5 %), operation room 12 (30 %), urine 3 (7.5 %), and industrial dialysis center 9 (22.5 %)) were isolated based on bacteriological methods confirmed by 16s rRNA gene using PCR technique. A se
... Show MoreOne of the most causative agents for many opportunistic diseases is the Pseudomonas aeruginosa which has a high percentage of multidrug resistance disease through construction of biofilm. The current study aimed for evaluating the correlation between quorum sensing genes (which is lasI gene) and biofilm formation. The biofilm construction and antibiotics susceptibility test were achieved for all the isolates under the study. The PCR and sequencing techniques were also carried out to detect the type of variation in lasI gene for each scheme of biofilm formation (weak, strong, and moderate). High antibiotic resistance was recorded among biofilm producing isolates. The genic pattern for the weak biof
... Show MoreSwarming is one of the most important virulence factors used by bacteria to invade new sites. This study aimed to test the effects of gentamicin on swarming motility of Pseudomonas aeruginosa, both phenotypically and molecularly. The present results revealed that 11/25 isolates had gentamicin MIC of 1024 µg/ml. However, gentamicin at sub-minimal inhibitory concentration significantly (P< 0.05) reduced the diameter of swarming in all P. aeruginosa isolates. Noticeably the mean and median swarming diameter before treatment with gentamicin 5.557 and 5.816 cm respectively had significantly (P < 0.001) reduced to 0.871 and 0.766 cm respectively. At the molecular level, amrZ (a global regulator of multiple genes) and
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