Bacteria 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 colonies on congored agar: very black colonies , black colonies and red colonies .Results indicated that addition of extracted genomic DNA to microtitre-plate cultures stimulate biofilm formation(either endogenous or exogenous DNA).
Pseudomonas 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
... Show MoreIntroduction: Biocides are commonly used for disinfection in a variety of contexts. They are generally used to avoid infection by controlling biofilm on medical equipment. However, the literature lacks information on the effect of biocide on efflux pump gene expression. Objective: To determine the influence of biocide on biofilm development and efflux pump acrA and ramA gene expression. Methodology: The microtiter plate method was used to identify biofilm development in 80 isolates of K. pneumoniae. The minimal inhibitory concentrations (MIC) of three biocides (quaternary ammonium compound (QAC), chlorohexidine digluconate, and chloroxylenol) were estimated. The effect of QAC on the intensity and viability of biofilms was investigated as we
... Show MoreThe D-enantiomers of amino acids have been thought to have relatively insignificant function in biological processes like, D-amino acids are sometimes found in proteins that are not synthesized by ribosomes. While L-amino acids clearly permanent in nature, D-amino acids have previously inapprehensible regulatory roles in the bacterial kingdom, any diverse of bacterial phyla made from these D-amino acids regulate cell wall remodeling in stationary phase and cause biofilm dispersal in aging bacterial communities. Clarification the mechanism by which D-amino acids given cell wall reorganization and biofilm disassembly will undoubtedly discover new paradigms for understanding how extra cytoplasmic processes are regulated as well as lead to d
... Show MoreResistance to aminoglycosids is a great problem to therapeutics. Aminoglycoside acetyltransferase producing Pseudomonas aeruginosa have been reported to be important cause of nosocomial infections. The purpose of this study was to determine the occurrence of aminoglycoside acetyltransferase. A total of 200 clinical and environmental samples were collected over period of five months. The P. aeruginosa isolates were confirm their identification, antibiotic susceptibility profile according to vitek2 compact system. The isolates were subjected to polymerase chain reaction (PCR) assays with specific primers for aac (6')-I, aac (6')-Ib, aac (3')-I . Only 32 (16.%) P. aeruginosa isolates were recovered from the samples. in present investigation
... Show MoreIn humans, Pseudomonas aeruginosa is the second most frequent gram negative nosocomial pathogen in hospitals and has the highest case-fatality rate of all hospital-acquired bacteremia because of the hardy resistance of these bacteria to mechanical cleansing as well as to disinfectant, and many antibiotics. The susceptibility of bacteria against the antibiotics is modulated by several local factors such as temperature which modified drug efficacy, so this study was carried out to evaluate the effect of different temperature (20,42,45)Ċon the susceptibility of Pseudomonas aeruginosa to the minimum inhibitory concentrations (MIC) of the antimicrobial agents before and after irradiation. The samples collected from 150 persons suffering from
... Show MoreAcinetobacter baumannii received attention for its multi-drug resistant associated with many severe infections and outbreaks in clinical environment. The aims of the study are to investigate the antibiotic susceptibility profile of clinically isolated A. baumannii, biofilm production, and the efficiency of Low Frequency Ultrasound (LFU) and honey to attenuate biofilm production. A total of 100 samples were taken from different sources from Baghdad hospitals. The susceptibility patterns revealed the percentage of pan drug resistant (PDR) isolates were 1.5 %, 72.7 % were extended drug resistant (XDR), 16.7 % were multidrug resistant (MDR), and 9.1 % were non MDR and sensitive to most antibiotics used. The ability to form
... Show MoreUrinary Tract Infection is an infection that caused by the members of the genus
Proteus that depends mainly on the availability of virulence factors ;Various
virulence factors including biofilm, swarming migration , polysaccharide
,heamolysin,protease, DNase, urease production weredetermined for 45Proteus
isolates that obtained from clinical specimens of Urinry Tract Infection patient .
The distribution of virulence factors was showed variation among the testedisolates
and strain specific in most cases. All Proteus isolates showed 45 (100%)biofilm ,
polysaccharide andSwarming capabilities with different extents. High
ureaseproduction was demonstrated in most isolates 40 (88.8%);In addition, they
were abling to
Forty different samples (water and soil) were collected from different places in Iraq and Syria. Only (6) isolates showed the ability to grow and utilize agar as a sole source of carbon and energy. Morphological, cultural characterization and biochemical tests confirmed that These isolates belonging to genus Pseudomonas (HK1-HK6) .Plasmid profiles results showed that these isolates were harbored (2 -3) small Plasmids . HK1 isolate was selected because of its efficiency and ability to grow in high density on agar media for transformation and curing experiments, these were checked by transformation experiments after their expression in E. coli MM294. The genes responsible for agar utilization were located on thes
... Show MoreTwenty-seven S. aureus isolates were obtained from patients referring various hospitals in Baghdad. Only 17 isolates produced DNase. SNase was extracted and purified from Saphylococcus aureus 3 isolate since it produces the largest zone of clearance on DNase agar. Nevertheless, only those phenotypically-producer of DNase harboured nuc gene. Present study revealed that the crude enzyme had a specific activity of 50.66 unit/mg; while it reached 241 unit/mg after ion exchange chromatography using carboxymethyl cellulose column. SDS-PAGE showed a single sharp band with an approximately 16.8 kDa molecular weight. A matter indicates that the enzyme is consistently pure. Results proved that SNase was able to significantly (P< 0.05) reduce th
... Show MorePseudomonas aeruginosa gram-negative, bacilli and facultative aerobic, P. aeruginosa cause cystic fibrosis patients, wounds, burns, and immunodeficienct patients, that have many virulence factors such as pyocyanin , cytotoxic ,biofilm formation and motility, Eighty-eight isolates belonging to P. aeruginosa were collected including the 66 clinical isolates obtained from different hospitals in Baghdad and were from different sources and 22 environmental isolates from previous studies of soil near oil fields. Microscopical and cultural characteristics were studied and diagnosed using biochemical tests, VITEC device, their ability to adhere to non-living (Polystyrene), living cell line (A549) and cytotoxicity of bacterial filtrate
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