scholarly journals COLICINE K

1958 ◽  
Vol 108 (5) ◽  
pp. 731-752 ◽  
Author(s):  
Tsunehisa Amano ◽  
Walther F. Goebel ◽  
Elizabeth Miller Smidth
Keyword(s):  
Neutralizing Antibody ◽  
Protein Component ◽  
The Other ◽  
Serological Relationship ◽  
E Coli ◽  
O Antigen ◽  
Two Agents ◽  
Antigen Complex

By immunological means it has been shown that colicine K is associated with the O antigen of the colicinogenic bacillus E. coli K235 L+OC+. The colicine K-O antigen complex elicits the formation of at least two types of antibodies, one a precipitin, the other a colicine-neutralizing antibody. The first precipitates colicine K without neutralizing it, the second neutralizes the colicine without precipitating it. Unlike the purified colicine K complex, the colicine protein component of the O antigen is precipitable by the neutralizing antibody. There is no demonstrable serological relationship between colicine K and phage T6. These two agents must be considered to be separate and distinct entities.

scholarly journals The O-Antigen Gene Cluster of Escherichia coli O55:H7 and Identification of a New UDP-GlcNAc C4 Epimerase Gene

2002 ◽  
Vol 184 (10) ◽  
pp. 2620-2625 ◽  
Author(s):  
Lei Wang ◽  
Sandy Huskic ◽  
Adam Cisterne ◽  
Deborah Rothemund ◽  
Peter R. Reeves
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Gene Cluster ◽  
Gene Clusters ◽  
The Other ◽  
Recombination Site ◽  
E Coli ◽  
Antigen Gene ◽  
O Antigen ◽  
Usual Location

ABSTRACT Escherichia coli O55 is an important antigen which is often associated with enteropathogenic E. coli clones. We sequenced the genes responsible for its synthesis and identified genes for O-antigen polymerase, O-antigen flippase, four enzymes involved in GDP-colitose synthesis, and three glycosyltransferases, all by comparison with known genes. Upstream of the normal O-antigen region there is a gne gene, which encodes a UDP-GlcNAc epimerase for converting UDP-GlcNAc to UDP-GalNAc and is essential for O55 antigen synthesis. The O55 gne product has only 20 and 26% identity to the gne genes of Pseudomonas aeruginosa and E. coli O113, respectively. We also found evidence for the O55 gene cluster's having evolved from another gene cluster by gain and loss of genes. Only three of the GDP-colitose pathway genes are in the usual location, the other two being separated, although nearby. It is thought that the E. coli O157:H7 clone evolved from the O55:H7 clone in part by transfer of the O157 gene cluster into an O55 lineage. Comparison of genes flanking the O-antigen gene clusters of the O55:H7 and O157:H7 clones revealed one recombination site within the galF gene and located the other between the hisG and amn genes. Genes outside the recombination sites are 99.6 to 100% identical in the two clones, while most genes thought to have transferred with the O157 gene cluster are 95 to 98% identical.

scholarly journals COLICINE K

1958 ◽  
Vol 107 (2) ◽  
pp. 185-209 ◽  
Author(s):  
Walther F. Goebel ◽  
Guy T. Barry
Keyword(s):  
Culture Medium ◽  
Protein Component ◽  
Chemical Fractionation ◽  
E Coli ◽  
O Antigen ◽  
K Activity

By chemical fractionation a substance having colicine K activity has been obtained from the culture medium of E. coli K235 L+O. Colicine K activity was found associated with the O antigen of this microorganism. When the O antigen was dissociated, colicine K activity remained with the protein component of the antigen.

scholarly journals The Isolation of Colicine V and a Study of Its Immunological Properties

1962 ◽  
Vol 45 (4) ◽  
pp. 125-141 ◽  
Author(s):  
John J. Hutton ◽  
Walther F. Goebel
Keyword(s):  
Antibacterial Activity ◽  
Protein Complex ◽  
Culture Medium ◽  
Serological Relationship ◽  
Immunological Properties ◽  
E Coli ◽  
O Antigen

Colicine V has been obtained from the culture medium in which the colicinogenic bacillus E. coli K357 L_T is grown. The material is electrophoretically homogeneous and proves to be a lipocarbohydrate protein complex identical with the type-specific O antigen of the parent bacillus. Colicine V is toxic both for mice and for rabbits and readily stimulates the elaboration of precipitins and bacterial agglutinins, as well as antibodies which neutralize the antibacterial activity of the colicine itself. The colicine is also toxic for certain strains of Enterobacteriaceae. Although colicine V and colicine K, previously described in this laboratory, have many properties in common, they exhibit no cross-serological relationship whatsoever.

scholarly journals Equine intestinal O-seroconverting temperate coliphage Hf4s: genomic and biological characterization

2021 ◽  
Author(s):  
Eugene E Kulikov ◽  
Alla K Golomidova ◽  
Alexandr D Efimov ◽  
Ilya S Belalov ◽  
Maria A Letarova ◽  
...  
Keyword(s):  
The Other ◽  
Biological Characterization ◽  
Virulent Phage ◽  
E Coli ◽  
O Antigen ◽  
Primary Receptor ◽  
Phage P22 ◽  
Almost All

Tailed bacteriophages constitute the bulk of the intestinal viromes of the vertebrate animals. However, the relationships between lytic and lysogenic lifestyles of the phages in these ecosystems are not always clear and may vary between the species or even between the individuals. The human intestinal (fecal) viromes are believed to be dominated by temperate phages, while in the horse feces the virulent phages are more prevalent. Almost all the isolates of horse fecal coliphages are virulent. Phage Hf4s is the first temperate equine intestinal coliphage characterized. It was isolated from the horse feces on the indigenous equine E. coli 4s strain. It is a podovirus, related to Lederbergvirus genus (including the well-characterized Salmonella phage P22). Hf4s recognizes the host O antigen as its primary receptor and possesses a functional O-antigen seroconversion cluster that renders the lysogens protected from the superinfection by the same phage and also abolishes the adsorption of some indigenous equine virulent coliphages, such as DT57C, while the other phages, such as G7C or phiKT retain the ability to infect E. coli 4s (Hf4s) lysogens.

Three-Dimensional Reconstruction of Two Forms of the Chaperonin GRO EL

1990 ◽  
Vol 48 (1) ◽  
pp. 258-259
Author(s):  
J.L. Carrascosa ◽  
G. Abella ◽  
S. Marco ◽  
M. Muyal ◽  
J.M. Carazo
Keyword(s):  
Three Dimensional ◽  
The Other ◽  
Two Dimensional ◽  
Series Method ◽  
Three Dimensional Reconstruction ◽  
Structural Components ◽  
E Coli ◽  
Dimensional Reconstruction ◽  
Morphogenetic Factors ◽  
Tilt Series

Chaperonins are a class of proteins characterized by their role as morphogenetic factors. They trantsiently interact with the structural components of certain biological aggregates (viruses, enzymes etc), promoting their correct folding, assembly and, eventually transport. The groEL factor from E. coli is a conspicuous member of the chaperonins, as it promotes the assembly and morphogenesis of bacterial oligomers and/viral structures.We have studied groEL-like factors from two different bacteria:E. coli and B.subtilis. These factors share common morphological features , showing two different views: one is 6-fold, while the other shows 7 morphological units. There is also a correlation between the presence of a dominant 6-fold view and the fact of both bacteria been grown at low temperature (32°C), while the 7-fold is the main view at higher temperatures (42°C). As the two-dimensional projections of groEL were difficult to interprete, we studied their three-dimensional reconstruction by the random conical tilt series method from negatively stained particles.

Disinfection of Fruits with Activated Water

2019 ◽  
Vol 10 ◽  
pp. 1864-1872
Author(s):  
Prof. Teodora P. Popova
Keyword(s):  
Antimicrobial Activity ◽  
Aqueous Solutions ◽  
Antimicrobial Properties ◽  
The Other ◽  
Gram Negative Bacteria ◽  
High Antimicrobial Activity ◽  
Gram Negative ◽  
E Coli ◽  
Number Of Microorganisms ◽  
Lower Effect

The effect of ionized aqueous solutions (anolytes and catholyte) in the processing of fruits (cherries, morellos, and strawberries) for decontamination has been tested. Freshly prepared analytes and catholyte without the addition of salts were used, as well as stored for 7 months anolytes, prepared with 0.5% NaCl and a combination of 0.5% NaCl and 0.5% Na2CO3. The anolyte prepared with a combination of 0.5% NaCl and 0.5% Na2CO3, as well as the anolyte obtained with 0.5% NaCl, exhibit high antimicrobial activity against the surface microflora of strawberries, cherries, and sour cherries. They inactivate E. coli for 15 minutes. The other species of the fam. Enterobacteriaceae were also affected to the maximum extent, as is the total number of microorganisms, especially in cherries and sour cherries. Even stored for 7 months, they largely retain their antimicrobial properties. Anolyte and catholyte, obtained without the addition of salts, showed a lower effect on the total number of microorganisms, but had a significant effect on Gram-negative bacteria, and especially with regard to the sanitary indicative E. coli.

Antibacterial Activity of Thujaoccidentalis,ThujaorientalisandChamaecyparisobtusa

2017 ◽  
Vol 8 (03) ◽  
Author(s):  
Kyoung- Sun Seo ◽  
Seong Woo Jin ◽  
Seongkyu Choi ◽  
Kyeong Won Yun
Keyword(s):  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Antibacterial Agent ◽  
Methanol Extract ◽  
The Other ◽  
Diffusion Method ◽  
E Coli ◽  
Agar Diffusion ◽  
Agar Diffusion Method ◽  
Crude Methanol Extract

The antibacterial activity of three Cupressaceae plants (Thujaoccidentalis,ThujaorientalisandChamaecyparisobtusa) was tested against three bacteria using the agar diffusion method. The ether and ethylacetate fraction of crude methanol extract from the three plants showed potent antibacterial activity against the tested microorganisms. The result showed that Staphylococcus aureus revealed the most sensitivity among the tested bacteria. Thujaoccidentalisether fraction and Thujaorientalis hexane fraction exhibited the highest antibacterial activity against Staphylococcus aureus. E. coli was shown the highest MIC values compared to the other two tested bacteria, which indicates the lowest antibacterial activity against the bacterium. This study promises an interesting future for designing a potentially active antibacterial agent from the three Cupressaceae plants.

Assessment of the exposure of swimmers to microbiological contaminants in fresh waters

1997 ◽  
Vol 35 (11-12) ◽  
pp. 157-163 ◽  
Author(s):  
G. J. Medema ◽  
I. A. van Asperen ◽  
A. H. Havelaar
Keyword(s):  
Geometric Mean ◽  
Microbiological Quality ◽  
The Other ◽  
Pollution Level ◽  
Intestinal Infection ◽  
E Coli ◽  
Faecal Pollution ◽  
Run Off ◽  
Thermotolerant Coliforms ◽  
Mean Concentration

As part of a prospective cohort study among triathletes to determine a relationship between the microbiological quality of fresh bathing water and the risk of acquiring an intestinal infection, the exposure of the triathletes to microbiological contaminants was assessed. Waters were collected at seven triathlons (swimming course 1–1.5km) held in the summer of 1993 and 1994 to have a range of water qualities. All were influenced by sewage effluents, most also by agricultural run-off. Samples were collected several weeks before the event to establish a sampling programme (1993) and during the actual exposure of the triathletes (1993 and 1994) and examined for thermotolerant coliforms alone (samples preceding the event) and for E. coli, faecal enterococci, Staphylococcus aureus, F-specific RNAphages, enteroviruses (1993 and 1994) and for thermophilic Campylobacter, Salmonella, Aeromonas, Plesiomonas shigelloides and Pseudomonas aeruginosa (1993). The samples taken in the weeks before the exposure showed significant differences in thermotolerant coliform concentration between locations, depths and times. Also during swimmer exposure, significant differences occurred in microorganism levels at the different sampling points over the swimming course. As the triathletes swam as a group, they were exposed to approximately the same water at the same time. The geometric mean concentration was used to characterise each site. In the epidemiological study, the risk of an intestinal infection correlated with the concentration of thermotolerant coliforms and E. coli but not with the other parameters. The geometric mean concentration of thermotolerant coliforms at the triathlons ranged from 11–330/100mL and 54–1,200/100mL E. coli. Ranking of the seven sites by faecal pollution level, based on the geometric mean concentration of a faecal indicator, resulted in a different ranking for each indicator. At the fresh water sites studied, only the ratio between the geometric mean density of E. coli and thermotolerant coliforms was constant. The ratio between the other parameters related to faecal pollution (faecal enterococci, F-specific RNA phages, enteroviruses) varied considerably. Water quality standards relating to faecal pollution can only be based on parameters that show a significant correlation with risk of intestinal illness.

Spheroplasts of enteropathogenic Escherichia coli. I. Biological characteristics

1968 ◽  
Vol 14 (6) ◽  
pp. 675-678 ◽  
Author(s):  
B. Diena ◽  
R. Wallace ◽  
L. Greenberg
Keyword(s):  
Escherichia Coli ◽  
Tissue Culture ◽  
Biological Characteristics ◽  
Enteropathogenic Escherichia Coli ◽  
E Coli ◽  
O Antigen ◽  
Pathogenic Serotypes

The properties of glycine-induced spheroplasts of six pathogenic serotypes of E. coli were investigated. Fimbriae and flagella appeared to be only partially synthesized as was the somatic O antigen. Cytopathogenicity of these spheroplasts for tissue culture was reduced and the infection of the monolayers was retarded as compared with the normal bacillary forms. Sensitivity to phage was almost completely lost, suggesting that glycine had either interfered with the synthesis of phage receptors or had altered the mucopeptide layerwhich is the substrate for phage enzymes. Alternatively, the phage may become a prophage inside the spheroplast with the loss of virulence.

scholarly journals Comparative Study of Ag Nanostructures: Molecular Simulations, Electrochemical Behavior, and Antibacterial Effect

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Álvaro de Jesús Ruíz-Baltazar ◽  
Simón Yobanny Reyes-López ◽  
D. Larrañaga ◽  
R. Pérez
Keyword(s):  
Cyclic Voltammetry ◽  
Ethylene Glycol ◽  
Comparative Study ◽  
Sodium Borohydride ◽  
Electrochemical Behavior ◽  
Antibacterial Effect ◽  
Chemical Reduction ◽  
Molecular Simulations ◽  
The Other ◽  
E Coli

Nanoparticles of Ag with different sizes and structures were obtained and studied. Two methods for reductions of Ag ions were employed, chemical reduction by sodium borohydride and ethylene glycol. Cuboctahedral and icosahedral structures were obtained. Molecular simulations were carried out in order to evaluate the reactivity of both structures. On the other hand, the electrochemical activity and antibacterial effect (E. coli) of the cuboctahedral and icosahedral structures were measured experimentally. The results obtained by molecular simulation, cyclic voltammetry, and antibacterial effect were compared and discussed in this work.

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