Core-Shell Structured Fe3O4/PPy Microspheres with High Magnetization for Purification of Plasmid DNA

2013 ◽  
Vol 716 ◽  
pp. 314-319 ◽  
Author(s):  
Hai Hui Jiang ◽  
Yan Zhou ◽  
Xiao Yun Han ◽  
Xin Cheng Chen ◽  
Yun Hua Hou ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Drug Delivery ◽  
Plasmid Dna ◽  
Magnetic Particles ◽  
Interfacial Polymerization ◽  
Core Shell ◽  
Magnetic Composite ◽  
Amino Group ◽  
High Quality ◽  
E Coli

Amino group-functionalized magnetic particles have wide applications in enzyme immobilization, DNA extraction, drug delivery, water purification, catalysis, and sensor. In this paper, Fe3O4/PPy microspheres with a well-defined coreshell structure have been prepared through an interfacial polymerization approach without surfactant. The magnetic composite spheres were characterized with XRD, FTIR, SEM, TEM, and magnetometry techniques, and further tested as the adsorbent to isolate plasmid DNA from Escherichia coli (E. coli) DH5α cells. The magnetic separation yields high-quality plasmid DNA in satisfying productivity as compared to the conventional phenolchloroform extraction.

One-Step Preparation of Competent E. coli: Transformation and Storage of Bacterial Cells in the Same Solution

2021 ◽  
Vol 2021 (11) ◽  
pp. pdb.prot101212 ◽  
Author(s):  
Michael R. Green ◽  
Joseph Sambrook
Keyword(s):  
Escherichia Coli ◽  
Convenient Method ◽  
Plasmid Dna ◽  
Transformation Efficiency ◽  
Bacterial Cells ◽  
E Coli ◽  
One Step ◽  
And Storage

This protocol describes a convenient method for the preparation, use, and storage of competent Escherichia coli. The reported transformation efficiency of this method is ∼5 × 107 transformants/µg of plasmid DNA.

scholarly journals Analysis of crystalline and solution states of ligand-free spermidine N-acetyltransferase (SpeG) from Escherichia coli

2019 ◽  
Vol 75 (6) ◽  
pp. 545-553 ◽  
Author(s):  
Ekaterina V. Filippova ◽  
Steven Weigand ◽  
Olga Kiryukhina ◽  
Alan J. Wolfe ◽  
Wayne F. Anderson
Keyword(s):  
Escherichia Coli ◽  
Vibrio Cholerae ◽  
Crystal Structures ◽  
Coenzyme A ◽  
Amino Group ◽  
Acetyl Coenzyme A ◽  
E Coli ◽  
Ligand Free ◽  
Acetyl Group ◽  
Terminal Amino

Spermidine N-acetyltransferase (SpeG) transfers an acetyl group from acetyl-coenzyme A to an N-terminal amino group of intracellular spermidine. This acetylation inactivates spermidine, reducing the polyamine toxicity that tends to occur under certain chemical and physical stresses. The structure of the SpeG protein from Vibrio cholerae has been characterized: while the monomer possesses a structural fold similar to those of other Gcn5-related N-acetyltransferase superfamily members, its dodecameric structure remains exceptional. In this paper, structural analyses of SpeG isolated from Escherichia coli are described. Like V. cholerae SpeG, E. coli SpeG forms dodecamers, as revealed by two crystal structures of the ligand-free E. coli SpeG dodecamer determined at 1.75 and 2.9 Å resolution. Although both V. cholerae SpeG and E. coli SpeG can adopt an asymmetric open dodecameric state, solution analysis showed that the oligomeric composition of ligand-free E. coli SpeG differs from that of ligand-free V. cholerae SpeG. Based on these data, it is proposed that the equilibrium balance of SpeG oligomers in the absence of ligands differs from one species to another and thus might be important for SpeG function.

scholarly journals Utilization of Mn-Doped ZnSe/ZnS Core/Shell Quantum Dots for Rapid Detection of Escherichia coli O157:H7 and Methicillin-Resistant Staphylococcus aureus

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Thi-Diem Bui ◽  
Quang-Liem Nguyen ◽  
Thi-Bich Luong ◽  
Van Thuan Le ◽  
Van-Dat Doan
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Quantum Dots ◽  
Fluorescent Labeling ◽  
Core Shell ◽  
Bacterial Cells ◽  
Bacterial Strains ◽  
Methicillin Resistant ◽  
E Coli ◽  
Mn Doped

In this study, Mn-doped ZnSe/ZnS core/shell quantum dots (CSQDs) were synthesized in aqueous solution using polyethylene glycol as a surface stabilizer and successfully applied in the detection of Escherichia coli O157:H7 and methicillin-resistant Staphylococcus aureus (MRSA) for the first time. The CSQDs were conjugated with anti-E. coli antibody and anti-MRSA antibody via protein A supported by 1-ethyl-3-(-3-dimethylaminopropyl)carbodiimide hydrochloride for fluorescent labeling of the intact bacterial cells. The detection was performed for the bacterial strains cultivated in Luria-Bertani liquid medium. The obtained results indicate that E. coli O157:H7 and MRSA can be detected within 30 min at a high sensitivity of 101 CFU/mL. This labeling method based on the highly fluorescent CSQDs may have great potential for use in the food industry to check and prevent outbreaks of foodborne illness.

scholarly journals The Complete Genome Sequence of Escherichia coli EC958: A High Quality Reference Sequence for the Globally Disseminated Multidrug Resistant E. coli O25b:H4-ST131 Clone

PLoS ONE ◽  
2014 ◽  
Vol 9 (8) ◽  
pp. e104400 ◽  
Author(s):  
Brian M. Forde ◽  
Nouri L. Ben Zakour ◽  
Mitchell Stanton-Cook ◽  
Minh-Duy Phan ◽  
Makrina Totsika ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Genome Sequence ◽  
Complete Genome Sequence ◽  
Complete Genome ◽  
Multidrug Resistant ◽  
Reference Sequence ◽  
High Quality ◽  
E Coli ◽  
St131 Clone

scholarly journals Natural Transformation of Plasmid DNA in Escherichia coli in Sterilized Soil Column

1970 ◽  
Vol 25 (1) ◽  
pp. 49-52
Author(s):  
M Mahabub-Uz-Zaman ◽  
Zia Uddin Ahmed
Keyword(s):  
Escherichia Coli ◽  
Plasmid Dna ◽  
Natural Transformation ◽  
Soil Column ◽  
Limiting Factor ◽  
Broad Host Range ◽  
E Coli ◽  
Competent Cells ◽  
Broad Host Range Plasmid ◽  
Plasmid Puc18

The present study was carried out to assess transformability of natural and laboratory strains of Escherichia coli by plasmid DNA under different transformation conditions in sterilized soil column. Transformation experiments were carried out in laboratory conditions and in sterile soil columns with CaCl2-treated competent cells and non-competent cells at log phase and stationary phase of growth using the broad host range plasmid pUC18. In soil column experiments, transformants were obtained after CaCl2 induced competence in both E. coli K12 DH5α and strain BM09 in the frequency of 10-8 to 10-9. In natural transformation assays, transformants appeared only in log phase cells of strain DH5α at a lower frequency (5.0 x 10-9), and in CaCl2-competent BM09 cells, but not in fresh cells. Thus the major limiting factor for natural transformation in environmental E. coli in soil column is probably the absence of a competent state. The significance of this finding has been discussed with respect to generally observed lower antibiotic resistance in environmental E. coli isolates from aquatic sources. Keywords: Natural transformation; Plasmid DNA; Escherichia coli; Competent stateDOI: http://dx.doi.org/10.3329/bjm.v25i1.4856 Bangladesh J Microbiol, Volume 25, Number 1, June 2008, pp 49-52

scholarly journals Escherichia coli strains from ostriches and their sensitivity to antimicrobial substances

2016 ◽  
Vol 19 (2) ◽  
pp. 415-423 ◽  
Author(s):  
J. Ščerbová ◽  
A. Lauková
Keyword(s):  
Escherichia Coli ◽  
Age Groups ◽  
Coliform Bacteria ◽  
High Quality ◽  
E Coli ◽  
Antimicrobial Substances ◽  
Resistant Strains ◽  
Mixture Samples ◽  
Tof Ms

AbstractOstriches are bred especially for their high-quality meat. There is a lack of knowledge concerning the ostrich’s microflora.Escherichia coliis a commensal microorganism of the poultry intestine, ostriches included. However, some strains may become pathogenic. This study was therefore undertaken to detect coliform bacteria in ostrich faeces and to test their antibiotic profile and sensitivity to enterocins. Faeces (n=54, 18 mixture samples from 3 different age groups of 140 ostriches) were sampled to isolate coliform bacteria. The counts of coliform bacteria varied from 5.69 ± 2.4 log10 CFU/g to 5.73 ± 2.4 CFU/g. Pure colonies were identified using MALDI-TOF MS mass spectrometry and confirmed by phenotypization. Seventy-one strains were allotted to the speciesE. coli. Sixty-four of those 71 strains caused hemolysis. They were mostly polyresistant to antibiotics. Thirty-two poly-resistant strains ofE. coliwere sensitive to enterocins. These strains were most sensitive to Ent 9296 (26 strains). Moreover, Ent EM41 produced byE. faeciumEM41 (isolated from ostrich faeces) inhibited the growth of 20 strains, reaching activity of 100 AU/ml. Our results indicate the possibility of enterocins being used for prevention/reduction of coliforms. Of course,in vivostudies are also being processed.

scholarly journals Targeted Delivery of Narrow-Spectrum Protein Antibiotics to the Lower Gastrointestinal Tract in a Murine Model of Escherichia coli Colonization

2021 ◽  
Vol 12 ◽  
Author(s):  
Nuria Carpena ◽  
Kerry Richards ◽  
Teresita D. J. Bello Gonzalez ◽  
Alberto Bravo-Blas ◽  
Nicholas G. Housden ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Drug Delivery ◽  
Controlled Release ◽  
Animal Models ◽  
Targeted Delivery ◽  
Intestinal Colonization ◽  
Ph Responsive ◽  
Human Gut ◽  
E Coli

Bacteriocins are narrow-spectrum protein antibiotics that could potentially be used to engineer the human gut microbiota. However, technologies for targeted delivery of proteins to the lower gastrointestinal (GI) tract in preclinical animal models are currently lacking. In this work, we have developed methods for the microencapsulation of Escherichia coli targeting bacteriocins, colicin E9 and Ia, in a pH responsive formulation to allow their targeted delivery and controlled release in an in vivo murine model of E. coli colonization. Membrane emulsification was used to produce a water-in-oil emulsion with the water-soluble polymer subsequently cross-linked to produce hydrogel microcapsules. The microcapsule fabrication process allowed control of the size of the drug delivery system and a near 100% yield of the encapsulated therapeutic cargo. pH-triggered release of the encapsulated colicins was achieved using a widely available pH-responsive anionic copolymer in combination with alginate biopolymers. In vivo experiments using a murine E. coli intestinal colonization model demonstrated that oral delivery of the encapsulated colicins resulted in a significant decrease in intestinal colonization and reduction in E. coli shedding in the feces of the animals. Employing controlled release drug delivery systems such as that described here is essential to enable delivery of new protein therapeutics or other biological interventions for testing within small animal models of infection. Such approaches may have considerable value for the future development of strategies to engineer the human gut microbiota, which is central to health and disease.

scholarly journals α-Amidoamids as New Replacements of Antibiotics—Research on the Chosen K12, R2–R4 E. coli Strains

Materials ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5169
Author(s):  
Paweł Kowalczyk ◽  
Arleta Madej ◽  
Mateusz Szymczak ◽  
Ryszard Ostaszewski
Keyword(s):  
Escherichia Coli ◽  
Antibacterial Activity ◽  
Biological Activity ◽  
Plasmid Dna ◽  
Alkyl Chain ◽  
Antimicrobial Drugs ◽  
E Coli ◽  
Different Types ◽  
Preliminary Study ◽  
Selection Of

A preliminary study of α-amidoamids as new potential antimicrobial drugs was performed. Special emphasis was placed on selection of structure of α-amidoamids with the highest biological activity against different types of Gram-stained bacteria by lipopolysaccharide (LPS). Herein, Escherichia coli model strains K12 (without LPS in its structure) and R1–R4 (with different length LPS in its structure) were used. The presented work showed that the antibacterial activity of α-amidoamids depends on their structure and affects the LPS of bacteria. Moreover, the influence of various newly synthesized α-amidoamids on bacteria possessing smooth and rought LPS and oxidative damage of plasmid DNA caused by all newly obtained compounds was indicated. The presented studies clearly explain that α-amidoamids can be used as substitutes for antibiotics. The chemical and biological activity of the analysed α-amidoamids was associated with short alkyl chain and different isocyanides molecules in their structure such as: tetr-butyl isocyanide or 2,5-dimethoxybenzyl isocyanide. The observed results are especially important in the case of the increasing resistance of bacteria to various drugs and antibiotics.

scholarly journals Draft Genome Sequences of Two Enteroinvasive Escherichia coli Strains Representative of Major Enteroinvasive E. coli Clades

2021 ◽  
Vol 10 (23) ◽  
Author(s):  
Michael J. Sikorski ◽  
Tracy H. Hazen ◽  
Gopi Vyas ◽  
Jane M. Michalski ◽  
David A. Rasko
Keyword(s):  
Escherichia Coli ◽  
Draft Genome ◽  
Genomic Data ◽  
Genome Sequences ◽  
High Quality ◽  
Content Type ◽  
E Coli ◽  
Clinical Illness

There are six described pathotypes of Escherichia coli that cause significant clinical illness in humans. Enteroinvasive E. coli (EIEC) strains have been shown to be separated into three phylogenomic clades. To add to a limited body of EIEC genomic data, we report two high-quality draft genomes representing different EIEC phylogenomic clades.

scholarly journals Influence of an extract of Juglans regia on the growth of Escherichia coli, on the electrophoretic profile of plasmid DNA and on the radiolabeling of blood constituents

2008 ◽  
Vol 51 (spe) ◽  
pp. 163-168 ◽  
Author(s):  
Sebastião David Santos-Filho ◽  
Claudia Leite Diniz ◽  
Fernanda Santos do Carmo ◽  
Adenilson de Souza da Fonseca ◽  
Mario Bernardo-Filho
Keyword(s):  
Escherichia Coli ◽  
Blood Cell ◽  
Plasmid Dna ◽  
Juglans Regia ◽  
Protective Action ◽  
Agarose Gel ◽  
Cell Compartment ◽  
Blood Constituents ◽  
E Coli ◽  
Technetium 99M

The aim of this work was to study the influence of a walnut (Juglans regia) extract on the growth of Escherichia coli (E. coli) AB1157, on the plasmid DNA topology and on the labeling of blood constituents with technetium-99m (99mTc). An E. coli AB1157 culture, in stationary phase, was incubated with walnut and the growth of the culture was evaluated by optical density at 600 nm for 7 hours. Plasmid DNA samples were incubated with SnCl2 in presence or absence of walnut for 40 minutes, 0.8% agarose gel electrophoresis was performed, the gel was stained and the plasmid topological forms were visualized. Blood samples from Wistar rats were incubated with walnut extract and an assay of labeling of blood constituents with technetium-99m (99mTc) was performed. Blood cells and plasma were separated. The radioactivity in each fraction was counted and percentage of incorporated radioactivity (%ATI) was determined. The results presented an inhibitory action of the growth of the E. coli AB1157 culture, no protective action of the walnut extract in plasmid DNA treated with SnCl2. Moreover, walnut was also not capable to induce modifications in the DNA mobility in agarose gel but walnut was capable to decrease the distribution of 99mTc on the blood cell compartment. In conclusion, our experimental data suggest that in the walnut extract has substances with an effect on the growth of E. coli culture, a potential action to increase the SnCl2 effect on plasmid DNA and also is capable to alter the distribution of 99mTc on the blood cell compartment probably due to redoxi properties.

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