Staphylococcus aureus and Pseudomonas aeruginosa are the major globally distributed pathogens, which causes chronic and recalcitrant infections due to their capacity to produce biofilms in large part. Biofilm production represents a survival strategy in these species, allowing them to endure environmental stress by altering their gene expression to match their own survival needs. In this study, we co-cultured different clinical isolates of S. aureus and P. aeruginosa as mono- and mixed-species biofilms in a full-strength Brain Heart Infusion Broth (BHI) and in a 1000-fold diluted Brain Heart Infusion Broth (BHI/1000) using Microtiter plate assay and determination of colony-forming units. Furthermore, the effect of starvation stress on the expression of pslA and fnbA genes of both species was investigated using RT-PCR. This work indicated that starvation stress significantly increased the biofilm biomass and bacterial density in all mono and mixed biofilm-producing strains. Interestingly, co-culture biofilms exhibited higher resistance to starvation as compared to monoculture. The current results also showed that the expression of fnbA and pslA genes was up-regulated under starvation stress in mono-and coculture biofilm. meanwhile, up-regulates of both genes in co-culture biofilm was significantly higher than mono- species biofilm.
The purpose of this study to synthesize and characterize silver nanoparticles using phenolic compounds obtained from Camellia sinensis, to test the antibacterial properties of biosynthesized nanoparticles on the formation of biofilms in multidrug-resistant Pseudomonas aeruginosa. Ten isolates of P. aeruginosa were obtained from the Genetic Engineering and Biotechnology Institute laboratories of the University of Baghdad. By using the VITEK-2 system and culturing the isolates on cetrimide agar, the diagnosis was confirmed. Camellia sinensis silver nanoparticles (CAgNPs) were created using an extract of the plant's aqueous and methanolic leaves. Based on the results of the nanoparticle synthesis, spherical nanoparticles that may be single or
... Show MoreTwo isolates of Pseudomonas aeruginosa were isolated from patients with Urinary Tract Infection (UTI). The aim of this study was to determine the antimicrobial effect of alcoholic leaves extract of Salvia officinalis on Multidrug resistant (MDR) P. aeruginosa. Using the well diffusion test, the alcoholic leaves extract at 100mg/ml and 200 mg /ml was shown to possess antimicrobial activity against the tested microorganism. The inhibition zones of S. officinalis at 200 mg/ml, and 100 mg/ml of the extract showed diameters of 23mm and 20mm, respectively. But the diameters of the inhibition zones caused by treatment with the antibiotics Ciprofloxacin, Ticarcillin + Clavulanic acid, and Cefotaxime w
... Show MoreA new Schiff base (4-chlorophenyl)(phenyl methanimine (6R,7R)-3-methyl-8-oxo-7-(2-phenylpropanamido)-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate=HL=C29H24ClN3O4S) has been synthesized from β-lactam antibiotic (cephalexin mono hydrate (CephH)=(C16H19N3O5S.H2O) and 4- chlorobenzophenone. Metal mixed ligand complexes of the Schiff base were prepared from chloride salt of Fe(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II), in 50% (v/v) ethanol – water medium in aqueous ethanol(1:1) and Saccharin(C7H5NO3S) containing sodium hydroxide. Several physical tools in particular; IR, C:H:N , 1H NMR,13C NMR for ligand, melting point, molar conductance, magnetic moment. and determination of the percentage of the metal in the complexes by flame(AAS
... Show Morenew Schiff base 4-chlorophenyl)methanimine (6R,7R)-3-methyl-8-oxo-7-(2-phenylpropanamido)-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate= (HL)= C23H20 ClN3O4S) has been synthesized from β-lactam antibiotic (cephalexin mono hydrate(CephH)=(C16H19N3O5S.H2O) and 4-chlorobenzaldehyde . Figure(1) Metal mixed ligand complexes of the Schiff base were prepared from chloride salt of Fe(II),Co(II),Ni(II),Cu(II),Zn(II) and Cd (II), in 50% (v/v) ethanol –water medium (SacH ) .in aqueous ethanol(1:1) containing and Saccharin(C7H5NO3S) = sodium hydroxide. Several physical tools in particular; IR, CHN, 1H NMR, 13C NMR for ligand and melting point molar conductance, magnetic moment. and determination the percentage of the metal in the complexes by fl
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Seventy-six urine specimens were collected from of patients suffering from recurrent
urinary tract infections (UTIs). Specimens were bacteriologically analyzed, fifty
(65.8%) of isolated bacterial strains were belonged to E.coli. 100% of isolated
uropathogenic E.coli (UPEC)strains displayed a biofilm positive phenotype under
optimized condition using microtiter plate assay. 21 of E.coli strains classified as highly
positive biofilm producers (42%), and 29 (58%) as weakly positive biofilm producers.
During 2011; 300 milk and white cheese samples were collected from Baghdad markets. Out of 200 staphylococcal isolates isolated from milk and white cheese samples, the predominant species was Staphylococcus aureus 97 isolates (48%), followed by S.chromogenes 82 (41%) and 21 (11%) S.epidermidis isolates. S. aureus isolates were DNase, coagulase, protease, urease, lipase, gelatinase and slime layer producers, other species were variable in the production of such virulence factors. S. chromogenes was the most prevalent isolated staphylococcal species from milk samples; while cheese samples contaminated mainly by S. aureus.
A total of 165 clinical sample included Urine, Swab wounds and Burns were collected from Baghdad Governorate. Results showed that rate all isolates of E. coli was 50(30.3%) and rate of urine infection was 46(92%) and rate of swab wounds infection 4(8%). Where was diagnostic based on streaked on MacConkey agar, then single colony was transferred to Eosin Methylene Blue (EMB). Identification some of the biochemical test included: Catalase test, Oxidase test, Indole test, Methyl red, Vogues - Proskauer test and Citrate Utilization test. Then confirmed by the Vitek - 2 Compact System. The ability of E.coli isolate to biofilm formation to be studied it is considered one of the most important factors of virulence and has role in causing injury an
... Show MoreOut of 150 different specimens, 67 S. aureus isolate were isolated. However, 16sRNA gene was located only in 60 isolates. Moreover, mecA gene was located in 48 isolates; thereby MRSA covered 80% of all S. aureus isolates. Of considerable interest, pvl gene was detected in only six isolates (10%). Hence, the present work emphasizes the notion suggested that pvl is not an indicative of CA-MRSA.