19 research outputs found
Sonochemical coating of cotton and polyester fabrics with “Antibacterial” BSA and casein spheres
A novel antibacterial coating for cotton and polyester fabrics has been developed by using drug-loaded proteinaceous microspheres made of bovine serum albumin and casein proteins. The microbubbles were created and anchored
onto the fabrics (see figure) in a one-step reaction that lasts 3 min. The sonochemically
produced “antibacterial fabrics” have been characterized. The efficiency of
the sonochemical process in converting the native proteins into microspheres, encapsulating the drug, and coating the fabric has also been studied.This research was carried out as part of the activities of the LIDWINE Consortium, Contract No. NMP2-CT-2006-026741. LIDWINE is an IP Project of the 6th European Customers (EC) Program
Molecular features of heterogeneous vancomycin-intermediate Staphylococcus aureus strains isolated from bacteremic patients
<p>Abstract</p> <p>Background</p> <p>Heterogeneous vancomycin-intermediate <it>Staphylococcus aureus </it>(hVISA) bacteremia is an emerging infection. Our objective was to determine the molecular features of hVISA strains isolated from bacteremic patients and to compare them to methicillin resistant <it>S. aureus </it>(MRSA) and methicillin sensitive <it>S. aureus </it>(MSSA) blood isolates.</p> <p>Results</p> <p>We assessed phenotypic and genomic changes of hVISA (n = 24), MRSA (n = 16) and MSSA (n = 17) isolates by PCR to determine staphylococcal chromosomal cassette (SCC<it>mec</it>) types, Panton-Valentine leukocidin (PVL) and the accessory gene regulator (<it>agr</it>) loci. Biofilm formation was quantified. Genetic relatedness was assessed by PFGE. PFGE analysis of isolates was diverse suggesting multiple sources of infection. 50% of hVISA isolates carried SCC<it>mec </it>type I, 21% type II; 25% type V; in 4% the SCC<it>mec </it>type could not be identified. Among MRSA isolates, 44% were SCC<it>mec </it>type I, 12.5% type II, 25% type V, 12.5% were non-typable, and 6% were SCC<it>mec </it>type IVd. Only one hVISA isolate and two MSSA isolates carried the PVL. Biofilm formation and <it>agr </it>patterns were diverse.</p> <p>Conclusion</p> <p>hVISA isolates were diverse in all parameters tested. A considerable number of hVISA and MRSA strains carried the SCC<it>mec </it>type V cassette, which was not related to community acquisition.</p
Bioconversion of Airborne Methylamine by Immobilized Recombinant Amine Oxidase from the Thermotolerant Yeast Hansenula polymorpha
Aliphatic amines, including methylamine, are air-pollutants, due to their intensive use in industry and the natural degradation of proteins, amino acids, and other nitrogen-containing compounds in biological samples. It is necessary to develop systems for removal of methylamine from the air, since airborne methylamine has a negative effect on human health. The primary amine oxidase (primary amine : oxygen oxidoreductase (deaminating) or amine oxidase, AMO; EC 1.4.3.21), a copper-containing enzyme from the thermotolerant yeast Hansenula polymorpha which was overexpressed in baker’s yeast Saccharomyces cerevisiae, was tested for its ability to oxidize airborne methylamine. A continuous fluidized bed bioreactor (CFBR) was designed to enable bioconversion of airborne methylamine by AMO immobilized in calcium alginate (CA) beads. The results demonstrated that the bioreactor with immobilized AMO eliminates nearly 97% of the airborne methylamine. However, the enzymatic activity of AMO causes formation of formaldehyde. A two-step bioconversion process was therefore proposed. In the first step, airborne methylamine was fed into a CFBR which contained immobilized AMO. In the second step, the gas flow was passed through another CFBR, with alcohol oxidase from the yeast H. polymorpha immobilized in CA, in order to decompose the formaldehyde formed in the first step. The proposed system provided almost total elimination of the airborne methylamine and the formaldehyde
Formaldehyde Oxidizing Enzymes and Genetically Modified Yeast Hansenula polymorpha Cells in Monitoring and Removal of Formaldehyde
14+ MILLION TOP 1% MOST CITED SCIENTIST 12.2% AUTHORS AND EDITORS FROM TOP 500 UNIVERSITIES Olive Oil-Based Delivery of Photosensitizers for Bacterial Eradication
The Role of Wastewater Treatment Plants in the Environmental Dissemination of Antibiotic Resistant Bacteria (ARB) and Resistance Genes (ARG)
Effect of toluene on Pseudomonas stutzeri ST-9 morphology: Plasmolysis, cell size and formation of outer membrane vesicles
IIsolated toluene-degrading Pseudomonas stutzeri ST-9 bacteria were grown in a minimal medium containing toluene (100 mg L-1) (MMT) or glucose (MMG) as the sole carbon source, with specific growth rates of 0.019 h-1 and 0.042 h-1, respectively. Scanning (SEM) as well as transmission (TEM) electron microscope analyses showed that the bacterial cells grown to mid log in the presence of toluene possess a plasmolysis space. TEM analysis revealed that bacterial cells that were grown in MMT were surrounded by an additional "material" with small vesicles in between. Membrane integrity was analyzed by leakage of 260 nm absorbing material and demonstrated only 7% and 8% leakage from cultures grown in MMT compared to MMG. X-ray microanalysis showed a 4.3-fold increase in Mg and a 3-fold increase in P compared to cells grown in MMG. FACS analysis indicated that the permeability of the membrane to propidium iodide was 12.6% and 19.6% when the cultures were grown in MMG and MMT, respectively. The bacterial cell length increased by 8.5%Ă‚Ä…0.1 and 17% Ă‚Ä…2 as measured using SEM images and FACS analysis, respectively. The results obtained in this research show that the presence of toluene led to morphology changes such as plasmolysis, cell size and formation of outer membrane vesicles. However, it does not cause significant damage to membrane integrity.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author
Detection of giardia lamblia genotypes in sewage and in stool samples in Israel
Giardia lamblia is a protozoan parasite which causes a severe disease called Giardiasis. This study was conducted to determine the prevalence of Giardia cysts in raw wastewater and its prevalence in the study community. Furthermore, the prevalence of assemblages A and B in sewage was compared with their prevalence in stool samples tested positive for Giardia. All wastewater samples were found positive for Giardia at a concentration range of 10-12225 cysts/L. Positive stool samples contained Giardia at an average concentration of 1.4x105cysts/gr. Giardia assemblage A alone was detected in 38.2% of wastewater samples, whereas assemblage B was not detected separately. However, 61.8% of the samples were found to contain both assemblages. In stool samples, the majority 27 out of 50 (54%) were found to contain assemblage B, 34.6% contained assemblage A and only 11.5% contained a mix of both assemblages. The results of the study indicate that Giardia is highly prevalent in wastewater in Israel reflecting its prevalence in the community. In addition, assemblage A is highly prevalent in wastewater, whereas assemblage B is more prevalent in stool samples, suggesting milder and/or carrier state of infection for assemblage A.</p