Bacteriocins elaborated by strains of Escherichia coli and related species. They are proteins or protein-lipopolysaccharide complexes lethal to other strains of the same species.
An enediyne that alkylates DNA and RNA like MITOMYCIN does, so it is cytotoxic.
Proteins obtained from ESCHERICHIA COLI.
Proteins isolated from the outer membrane of Gram-negative bacteria.
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
Proteins found in the PERIPLASM of organisms with cell walls.
Infections with bacteria of the species ESCHERICHIA COLI.
Proteins found in any species of bacterium.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
The functional hereditary units of BACTERIA.
The measurement of the quantity of heat involved in various processes, such as chemical reactions, changes of state, and formations of solutions, or in the determination of the heat capacities of substances. The fundamental unit of measurement is the joule or the calorie (4.184 joules). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
Administration of nursing services for one or more clinical units.
Surveillance of drugs, devices, appliances, etc., for efficacy or adverse effects, after they have been released for general sale.
An activity distinguished primarily by an element of risk in trying to obtain a desired goal, e.g., playing a game of chance for money.
Primarily non-verbal tests designed to predict an individual's future learning ability or performance.
An agency of the PUBLIC HEALTH SERVICE concerned with the overall planning, promoting, and administering of programs pertaining to maintaining standards of quality of foods, drugs, therapeutic devices, etc.
Process that is gone through in order for a drug to receive approval by a government regulatory agency. This includes any required pre-clinical or clinical testing, review, submission, and evaluation of the applications and test results, and post-marketing surveillance of the drug.
That segment of commercial enterprise devoted to the design, development, and manufacture of chemical products for use in the diagnosis and treatment of disease, disability, or other dysfunction, or to improve function.
The sum of the weight of all the atoms in a molecule.
Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.
A group of glucose polymers made by certain bacteria. Dextrans are used therapeutically as plasma volume expanders and anticoagulants. They are also commonly used in biological experimentation and in industry for a wide variety of purposes.
Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.
A serine endopeptidase that is formed from TRYPSINOGEN in the pancreas. It is converted into its active form by ENTEROPEPTIDASE in the small intestine. It catalyzes hydrolysis of the carboxyl group of either arginine or lysine. EC 3.4.21.4.
The rate dynamics in chemical or physical systems.
Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)
Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.
Electric conductors through which electric currents enter or leave a medium, whether it be an electrolytic solution, solid, molten mass, gas, or vacuum.
A pyrrolo-quinoline having two adjacent keto-groups at the 4 and 5 positions and three acidic carboxyl groups. It is a coenzyme of some DEHYDROGENASES.
Material from which the casting mold is made in the fabrication of gold or cobalt-chromium castings. (Boucher's Clinical Dental Terminology, 4th ed, p168)
The process of producing a form or impression made of metal or plaster using a mold.
D-Glucose:1-oxidoreductases. Catalyzes the oxidation of D-glucose to D-glucono-gamma-lactone and reduced acceptor. Any acceptor except molecular oxygen is permitted. Includes EC 1.1.1.47; EC 1.1.1.118; EC 1.1.1.119 and EC 1.1.99.10.
A glucose dehydrogenase that catalyzes the oxidation of beta-D-glucose to form D-glucono-1,5-lactone, using NAD as well as NADP as a coenzyme.
Energy transmitted from the sun in the form of electromagnetic radiation.
A loose confederation of computer communication networks around the world. The networks that make up the Internet are connected through several backbone networks. The Internet grew out of the US Government ARPAnet project and was designed to facilitate information exchange.
Processes involved in the formation of TERTIARY PROTEIN STRUCTURE.
The sum or the stock of words used by a language, a group, or an individual. (From Webster, 3d ed)
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
Substances elaborated by specific strains of bacteria that are lethal against other strains of the same or related species. They are protein or lipopolysaccharide-protein complexes used in taxonomy studies of bacteria.
Esters formed between the aldehydic carbon of sugars and the terminal phosphate of guanosine diphosphate.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
A class of oxidized LDL receptors that contain LECTIN-like extracellular domains.

Estimation of the number of alpha-helical and beta-strand segments in proteins using circular dichroism spectroscopy. (1/848)

A simple approach to estimate the number of alpha-helical and beta-strand segments from protein circular dichroism spectra is described. The alpha-helix and beta-sheet conformations in globular protein structures, assigned by DSSP and STRIDE algorithms, were divided into regular and distorted fractions by considering a certain number of terminal residues in a given alpha-helix or beta-strand segment to be distorted. The resulting secondary structure fractions for 29 reference proteins were used in the analyses of circular dichroism spectra by the SELCON method. From the performance indices of the analyses, we determined that, on an average, four residues per alpha-helix and two residues per beta-strand may be considered distorted in proteins. The number of alpha-helical and beta-strand segments and their average length in a given protein were estimated from the fraction of distorted alpha-helix and beta-strand conformations determined from the analysis of circular dichroism spectra. The statistical test for the reference protein set shows the high reliability of such a classification of protein secondary structure. The method was used to analyze the circular dichroism spectra of four additional proteins and the predicted structural characteristics agree with the crystal structure data.  (+info)

Simplified methods for pKa and acid pH-dependent stability estimation in proteins: removing dielectric and counterion boundaries. (2/848)

Much computational research aimed at understanding ionizable group interactions in proteins has focused on numerical solutions of the Poisson-Boltzmann (PB) equation, incorporating protein exclusion zones for solvent and counterions in a continuum model. Poor agreement with measured pKas and pH-dependent stabilities for a (protein, solvent) relative dielectric boundary of (4,80) has lead to the adoption of an intermediate (20,80) boundary. It is now shown that a simple Debye-Huckel (DH) calculation, removing both the low dielectric and counterion exclusion regions associated with protein, is equally effective in general pKa calculations. However, a broad-based discrepancy to measured pH-dependent stabilities is maintained in the absence of ionizable group interactions in the unfolded state. A simple model is introduced for these interactions, with a significantly improved match to experiment that suggests a potential utility in predicting and analyzing the acid pH-dependence of protein stability. The methods are applied to the relative pH-dependent stabilities of the pore-forming domains of colicins A and N. The results relate generally to the well-known preponderance of surface ionizable groups with solvent-mediated interactions. Although numerical PB solutions do not currently have a significant advantage for overall pKa estimations, development based on consideration of microscopic solvation energetics in tandem with the continuum model could combine the large deltapKas of a subset of ionizable groups with the overall robustness of the DH model.  (+info)

Structure in the channel forming domain of colicin E1 bound to membranes: the 402-424 sequence. (3/848)

To explore the structure of the pore-forming fragment of colicin E1 in membranes, a series of 23 consecutive single cysteine substitution mutants was prepared in the sequence 402-424. Each mutant was reacted with a sulfhydryl-specific reagent to generate a nitroxide labeled side chain, and the mobility of the side chain and its accessibility to collision with paramagnetic reagents was determined from the electron paramagnetic resonance spectrum. Individual values of these quantities were used to identify tertiary contact sites and the nature of the surrounding solvent, while their periodic dependence on sequence position was used to identify secondary structure. In solution, the data revealed a regular helix of 11 residues in the region 406-416, consistent with helix IV of the crystal structure. Upon binding to negatively charged membranes at pH 4.0, helix IV apparently grows to a length of 19 residues, extending from 402-420. One face of the helix is solvated by the lipid bilayer, and the other by an environment of a polar nature. Surprisingly, a conserved charged pair, D408-R409, is located on the lipid-exposed face. Evidence is presented to suggest a transmembrane orientation of this new helix, although other topographies may exist in equilibrium.  (+info)

A cytotoxic ribonuclease targeting specific transfer RNA anticodons. (4/848)

The carboxyl-terminal domain of colicin E5 was shown to inhibit protein synthesis of Escherichia coli. Its target, as revealed through in vivo and in vitro experiments, was not ribosomes as in the case of E3, but the transfer RNAs (tRNAs) for Tyr, His, Asn, and Asp, which contain a modified base, queuine, at the wobble position of each anticodon. The E5 carboxyl-terminal domain hydrolyzed these tRNAs just on the 3' side of this nucleotide. Tight correlation was observed between the toxicity of E5 and the cleavage of intracellular tRNAs of this group, implying that these tRNAs are the primary targets of colicin E5.  (+info)

Characterization of nonenterotoxigenic Escherichia coli strains producing F17 fimbriae isolated from diarrheic lambs and goat kids. (5/848)

Forty-five ovine and caprine nonenterotoxigenic Escherichia coli strains producing F17-related fimbriae were characterized with respect to the fimbrial structural subunit and adhesin subtypes produced. In addition, several characteristics related to the virulence of strains producing F17 fimbriae were studied. Most of the strains (73%) possessed the f17cA structural subunit gene, whereas the f17aA and f17dA genes were detected only on three (6%) and two (4%) strains, respectively. The f17bA gene was not detected. All but one of these strains possessed the f17G genes of the adhesin subfamily II. The only strain having the f17G gene of subfamily I possessed the structural subunit gene f17dA. Sequencing of the f17A and f17G genes of four selected strains confirmed the association of f17cA and f17dA structural subunit genes with the f17G genes of the adhesin subfamily II. These results indicated that adhesins of the subfamily II are prominent among ovine and caprine isolates and that they are indistinctly associated with the F17 structural subunit subtypes on these field strains. CS31A- and CNF2-related genes were not detected. Most of the strains adhered in vitro to ovine intestinal brush borders (36 of 45) and agglutinated the erythrocytes of different species in the presence of D-mannose (39 of 45). F17-positive strains produced colicin V (57%) and were resistant to the bactericidal effect of serum (91%) in significantly higher percentages than F17-negative strains (34% produced colicin V, and 66% were serum resistant). Thus, most of the studied ovine and caprine strains showed phenotypic characteristics of septicemic strains.  (+info)

A theoretical and empirical investigation of the invasion dynamics of colicinogeny. (6/848)

A mathematical model describing the dynamics of a colicinogenic and a colicin-sensitive population propagated under serial transfer culture conditions was formulated. In addition, a series of in vitro invasion experiments using six representatives of the E colicin group was undertaken, together with the estimation of the growth rates and colicinogenic characteristics of the strains. Growth rates among the strains varied by up to 44%. There were 14-fold differences among strains in their lysis rates and there were up to 10-fold differences in the amount of colicin produced per lysed cell. The in vitro serial transfer invasion experiments revealed that regardless of initial frequency all colicinogenic strains succeeded in displacing the sensitive cell populations. The amount of time required for the colicin-sensitive cell population to be displaced declined as the initial frequency of the colicinogenic population increased and strains producing higher titres of colicin tended to displace the sensitive strain more rapidly. Overall, the observed dynamics of the invasion of colicinogenic strains was adequately described by the theoretical model. However, despite there being substantial differences among the strains in their growth rates and colicinogenic characteristics there were relatively few differences, observed or predicted, in the invasion dynamics of the six colicinogenic strains. These results suggest that the characteristics of different colicinogenic strains cannot be used to explain the extensive variation in the relative abundance of different colicins in natural populations of bacteria.  (+info)

Characterization of colicin S4 and its receptor, OmpW, a minor protein of the Escherichia coli outer membrane. (7/848)

Analysis of the nucleotide sequence of an Escherichia coli colicin S4 determinant revealed 76% identity to the pore-forming domain of the colicin A protein, 77% identity to the colicin A immunity protein, and 82% identity to the colicin A lysis protein. The N-terminal region, which is responsible for the Tol-dependent uptake of colicin S4, has 94% identity to the N-terminal region of colicin K. By contrast, the predicted receptor binding domain shows no sequence similarities to other colicins. Mutants that lacked the OmpW protein were resistant to colicin S4.  (+info)

Colicin E1 forms a dimer after urea-induced unfolding. (8/848)

Unfolding of the soluble colicin E1 channel peptide was examined with the use of urea as a denaturant; it was shown that it unfolds to an intermediate state in 8.5 M urea, equivalent to a dimeric species previously observed in 4 M guanidinium chloride. Single tryptophan residues, substituted into the peptide at various positions by site-directed mutagenesis, were employed as fluorescent probes of local unfolding. Unfolding profiles for specific sites within the peptide were obtained by quantifying the shifts in the fluorescence emission maxima of single tryptophan residues on unfolding and plotting them against urea concentration. Unfolding reported by tryptophan residues in the C-terminal region was not characteristic of complete peptide denaturation, as evidenced by the relatively blue-shifted values of the fluorescence emission maxima. Unfolding was also monitored by using CD spectroscopy and the fluorescent probe 2-(p-toluidinyl)-naphthalene 6-sulphonic acid; the results indicated that unfolding of helices is concomitant with the exposure of protein non-polar surface. Unfolding profiles were evaluated by non-linear least-squares curve fitting and calculation of the unfolding transition midpoint. The unfolding profiles of residues located in the N-terminal region of the peptide had lower transition midpoints than residues in the C-terminal portion. The results of unfolding analysis demonstrated that urea unfolds the peptide only partly to an intermediate state, because the C-terminal portion of the channel peptide retained significant structure in 8.5 M urea. Characterization of the peptide's global unfolding by size-exclusion HPLC revealed that the partly denatured structure that persists in 8.5 M urea is a dimer of two channel peptides, tightly associated by hydrophobic interactions. The presence of the dimerized species was confirmed by SDS/PAGE and intermolecular fluorescence resonance energy transfer.  (+info)

Colicins are plasmid-encoded antibiotics that are produced by and kill Escherichia coli and other related species. The frequency of colicinogeny is high, on average 30% of E. coli isolates produce colicins. Initial observations from one collection of 72 strains of E. coli (the ECOR collection) suggest that resistance to colicin killing is also ubiquitous, with over 70% of strains resistant to one or more colicins. To determine whether resistance is a common trait in E. coli, three additional strain collections were surveyed. In each of these collections levels of colicin production were high (from 15 to 50% of the strains produce colicins). Levels of colicin resistance were even higher, with most strains resistant to over 10 colicins. A survey of 137 non-E. coli isolates revealed even higher levels of resistance. We discuss a mechanism (pleiotropy) that could result in the co-occurrence of such high levels of colicin production and colicin resistance ...
A colicin is a type of bacteriocin produced by and toxic to some strains of Escherichia coli. Colicins are released into the environment to reduce competition from other bacterial strains. Colicins bind to outer membrane receptors, using them to translocate to the cytoplasm or cytoplasmic membrane, where they exert their cytotoxic effect, including depolarisation of the cytoplasmic membrane, DNase activity, RNase activity, or inhibition of murein synthesis. Channel-forming colicins (colicins A, B, E1, Ia, Ib, and N) are transmembrane proteins that depolarize the cytoplasmic membrane, leading to dissipation of cellular energy. These colicins contain at least three domains: an N-terminal translocation domain responsible for movement across the outer membrane and periplasmic space; a central domain responsible for receptor recognition; and a C-terminal cytotoxic domain responsible for channel formation in the cytoplasmic membrane. One domain regulates the target and binds to the receptor on the ...
This work has studied colicin translocation by using a periplasmic protection assay combined with an in vivo lux-reporter assay and a potassium release assay. Expressing the translocation domain of colicin A in the periplasm and challenging the cells with external colicins showed that the translocation of group A colicins is inhibited as it requires an interaction with the Tol system. Surprisingly, the TolA protein was found to play the major role during the translocation of both ColA and the endonuclease colicin E9 even though the latter colicin has no direct interaction with the TolA protein. This study also suggests that the interaction with TolB is important for both colicins A and E9. Moreover, a series of ColA constructs with a truncated T domain were made by site directed mutagenesis to define the important residues of the TolA and TolB boxes for their interaction with Tol proteins. The results showed that tyrosine 58 residue of the TolA box of colicin A is essential for TolA binding, ...
Four colicin A double-cysteine mutants possessing a disulfide bond in their pore-forming domain were constructed to study the translocation and the pore formation of colicin A. The disulfide bonds connected a-helices 1 and 2, 2 and 10, 3 and 9, or 3 and 10 of the poreforming domain. The disulfide bonds did not prevent the colicin A translocation through the Escherichia coli envelope. However, the mutated colicins were able to exert their in vivo channel activity only after reduction of their disulfide bonds. In vitro studies with brominated phospholipid vesicles and planar lipid bilayers revealed that the disulfide bond that connects the a-helices 2 and 10 prevented the colicin A membrane insertion, whereas the other double-cysteine mutants inserted into lipid vesicles. The disulfide bonds that connect either the a-helices 1 and 2 or 3 and 10 were unable to prevent the formation of a conducting channel in presence of membrane potential. These results indicate that a-helices 1, 2, 3, and 10 remain at the
The translocation of protein toxins into a cell relies on a myriad of protein-protein interactions. One such group of toxins are enzymatic E colicins, protein antibiotics produced by Escherichia coli in times of stress. These proteins subvert ordinary nutrient uptake mechanisms to enter the cell and unleash nuclease activity. We, and others, have previously shown that uptake of ColE9 (colicin E9) is dependent on engagement of the OM (outer membrane) receptors BtuB and OmpF as well as recruitment of the periplasmic protein TolB, forming a large supramolecular complex. Intriguingly, colicins bind TolB using a natively disordered region to mimic the interaction of TolB with Pal (peptidoglycan-associated lipoprotein). This is thought to trigger OM instability and prime the system for translocation. Here, we review key interactions in the assembly of this colicin translocon and discuss the key role disorder plays in achieving uptake. ...
Colicin E1 induces the efflux of carboxyfluorescein and calcein from liposomes whose phospholipid composition is similar to that of Escherichia coli. This colicin action takes place at protein-to-liposome ratios and within pH ranges that are physiologically meaningful. Colicin-induced permeability of carboxyfluorescein is not limited to the initial phase of colicin membrane interaction but is sustained thereafter. Colicin E1 requires negatively charged phospholipids in the liposomal membrane in order to bind and induce efflux.
Immunhistochemische Untersuchungen zur lokoregionären Verteilung von mTOR, p-mTOR und 4E-binding protein im Prostataraum tumortragender Prostaten mittels der Tissue Microarray- ...
The SCOP classification for the Colicin E3 immunity protein superfamily including the families contained in it. Additional information provided includes InterPro annotation (if available), Functional annotation, and SUPERFAMILY links to genome assignments, alignments, domain combinations, taxonomic visualisation and hidden Markov model information.
Two cases of successful molecular replacement using NMR trial models are presented. One is the crystal structure of the E. coli colicin immunity protein Im7; the other is the previously unreported crystal structure of the carboxy-terminal SH2 domain from the p85α subunit of human phosphatidylinositol 3-OH kinase complexed to a PDGF receptor-derived specificity peptide ...
A, comparison of the colicin M amino acid sequence with the sequences of predicted bacteriocins of Burkholderia amifaria MC40-6 (accession number AOTM72), Burkh
Authors: Figueiredo, Angelo; Whittaker, Sara; Knowling, Stuart; Radford, Sheena; Moore, Geoffrey. Citation: Knowling, Stuart; Figueiredo, Angelo Miguel; Whittaker, Sara B-M; Moore, Geoffrey; Radford, Sheena. Amino acid insertion reveals a necessary three-helical intermediate in the folding pathway of the colicin E7 immunity protein Im7. J. Mol. Biol. 392, 1074-1086 (2009).. Assembly members: ...
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Shop Lactococcin-A immunity protein ELISA Kit, Recombinant Protein and Lactococcin-A immunity protein Antibody at MyBioSource. Custom ELISA Kit, Recombinant Protein and Antibody are available.
TATDN3 antibody (TatD DNase domain containing 3) for WB. Anti-TATDN3 pAb (GTX106682) is tested in Human, Mouse samples. 100% Ab-Assurance.
E coli tolQ protein: from E coli; are involved in uptake of group A colicins & infection by filamentous bacteriophages; homologous to exbB protein; amino acid sequence given in first source
Linear diagram showing the approximate lengths of whole colicin Ia and the four carboxy-terminal fragments, CT-S, CT-M, CT-L, and CT-XL. The boundaries of the T
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Colicins, a class of antimicrobial compounds produced by bacteria, are thought to be important mediators of intra- and interspecific interactions, and are a significant factor in maintaining microbial diversity. Colicins B and M are among the most common colicins produced by Escherichia coli, and are usually encoded adjacently on the same plasmid. In this study, the characterization of a collection of E. coli isolated from Australian vertebrates revealed that a significant fraction of colicin BM strains lack an intact colicin B activity gene. The colicin B and M gene region was sequenced in 60 strains and it was found (with one exception) that all plasmids lacking an intact colicin B activity gene have an identical colicin gene structure, possessing a complete colicin B immunity gene and a 130 bp remnant of the B activity gene. A phylogenetic analysis of the colicin M and B operons and characterization of the plasmids suggested that ColBM plasmids with a truncated B activity gene have evolved on at
Binding of enzymatic E colicins to the vitamin B12 receptor, BtuB, is the first stage in a cascade of events that culminate in the translocation of the cytotoxic nuclease into the Escherichia coli cytoplasm and release of its tightly bound immunity protein. A dogma of colicin biology is that the toxin coiled-coil connecting its functional domains must unfold or unfurl to span the periplasm, with recent reports claiming this reaction is initiated by receptor binding. We report isothermal titration calorimetry data of BtuB binding the endonuclease toxin ColE9 and a disulfide form (ColE9S-S) where unfolding of the coiled-coil is prevented and, as a consequence, the toxin is biologically inactive. Contrary to expectation, the thermodynamics of receptor binding, characterized by large negative values for TDeltaS, are identical for the two colicins, arguing against any form of BtuB-induced unfolding. We go on to delineate key features of the colicin translocon that assembles at the cell surface after BtuB
Evidence is presented that ColV plasmid-mediated iron uptake, an important component of the virulence of invasive strains of Escherichia coli, is independent of colicin V synthesis and activity. A mutant of E. coli K-12 deficient in the biosynthesis of enterochelin (strain AN1937) was unable to grow on minimal agar containing the chelating agent α,α′-dipyridyl unless it was harboring the plasmid ColV-K30 (strain LG1315). Acquisition of the active plasmid-specified iron sequestering system was accompanied by marked enhancement of pathogenicity in experimental infections of mice. Mutants of strain LG1315 were isolated that were defective in iron uptake due to plasmid mutations. They were unchanged with respect to colicin production, but were significantly less virulent than the parent strain. Conversely, mutants isolated as defective in colicin V synthesis were normal for the plasmid-coded iron uptake mechanism and showed the same lethality for infected mice as did strain LG1315. Furthermore, ...
A strain of Escherichia coli, selected on the basis of its resistance to colicin N, reveals distinct structural and functional alterations in unspecific OmpF porin. A single mutation [Gly-119--,Asp (G119D)] was identified in the internal loop L3 that contributes critically to the formation of the construction inside the lumen of the pore. X-ray structure analysis to a resolution of 3.0 A reveals a locally altered peptide backbone, with the side chain of residue Asp-119 protruding into the channel, causing the area of the constriction (7 x 11 A in the wild type) to be subdivided into two intercommunicating subcompartments of 3-4 A in diameter. The functional consequences of this structural modification consist of a reduction of the channel conductance by about one-third, of altered ion selectivity and voltage gating, and of a decrease of permeation rates of various sugars by factors of 2-12. The structural modification of the mutant protein affects neither the beta-barrel structure nor those ...
Escherichia coli ST131 is a clinical challenge due to its multidrug resistant profile and successful global spread. They are often associated with complicated infections, particularly urinary tract infections (UTIs). Bacteriocins play an important role to outcompete other microorganisms present in the human gut. Here, we characterized bacteriocin-encoding plasmids found in ST131 isolates of patients suffering from a UTI using both short- and long-read sequencing. Colicins Ia, Ib and E1, and microcin V, were identified among plasmids that also contained resistance and virulence genes. To investigate if the potential transmission range of the colicin E1 plasmid is influenced by the presence of a resistance gene, we constructed a strain containing a plasmid which had both the colicin E1 and blaCMY-2 genes. No difference in transmission range was found between transformant and wild-type strains. However, a statistically significantly difference was found in adhesion and invasion ability. ...
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The Role of Bacteriocins in Mediating Bacterial Competitive Interactions. Explaining the coexistence of competing species is a major challenge in community ecology. In bacterial systems, competition is often driven by the production of bacteriocins, which are narrow-spectrum proteinaceous toxins that serve to kill closely related species, providing the producer better access to limited resources. Bacteriocin producers have been shown to competitively exclude sensitive, nonproducing strains. However, the dynamics between bacteriocin producers, each lethal to its competitor, are largely unknown. In this study, we used in vitro, in vivo and in silico models to study competitive interactions between bacteriocin producers. Two Escherichia coli strains were generated, each carrying a DNA-degrading bacteriocin (colicins E2 and E7). Using reporter-gene assays, we showed that each DNase bacteriocin is not only lethal to its opponent but, at lower doses, can also induce the expression of its opponents ...
Proteolyses of colicin E3 by both trypsin and subtilisin yield fragments of various molecular weights. On the basis of sodium dodecyl sulfate gel electrophoresis, tryptic cleavage yields peptides of molecular weight about 42 000 and 18 000, while the
On September 8, 2015, The Proceedings of the National Academy of Sciences published a study online titled, Broad and efficient control of major foodborne pathogenic strains of Escherichia coli by mixture of plant-produced colicins. The study advocates that colicins, which are nonantibiotic antimicrobial proteins that kill or inhibit the growth of other competing E. coli strains, could be used to effectively mitigate the risk of E. coli in meat and produce ...
The group A colicins and the DNA of many single-stranded filamentous bacteriophage are able to use combinations of the Tol proteins to gain entrance into or across the membrane of Escherichia coli. The TolA protein is a 421-amino acid residue integral membrane protein composed of three domains. Domain I, consisting of the amino-terminal 47 amino acids, contains a 21-residue hydrophobic segment that anchors the protein in the inner membrane. The remaining 374 amino acids, containing the other two domains, reside in the periplasmic space. Domain III, consisting of the carboxyl-terminal 120 residues, is considered to be the functional domain based on the location of the tolA592 deletion mutation. The internal 262 amino acids comprise domain II, which connects domains I and III together via short regions of polyglycine. It contains a large number of 3- to 5-residue polyalanine stretches, many of which have a repeat of the sequence Lys-Ala-Ala-Ala-(Glu/Asp). Circular dichroism analysis of different ...
Pyroptosis is a form of lytic programmed cell death initiated by inflammasomes, which detect cytosolic contamination or perturbation. This drives activation of caspase-1 or caspase-11/4/5, which cleave gasdermin D, separating its N-terminal pore-forming domain (PFD) from the C-terminal repressor dom …
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Scientists at the University of Pittsburgh School of Medicine have discovered a new biological pathway of innate immunity that ramps up inflammation and then identified agents that can block it, leading to increased survival ...
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British pop singer Cheryl Cole will no longer Factor into Simon Cowells reality singing competition plans stateside or back in her native United Kingdom, according to multiple reports out of Great Britain.
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ফুকো ১৯৫০ সালে তার agrégation সম্পন্ন করেন। École Normale-তে কিছু সময়ের জন্য কাজ করার পর তিনি লিলে বিশ্ববিদ্যালয়ে একটি পদ পেয়ে যান। এখানে ১৯৫৩ থেকে ১৯৫৪ সাল পর্যন্ত দর্শনের প্রভাষকের পদে চাকরি করেন। ১৯৫৪ সালে তার প্রথম বই প্রকাশিত হয় যার নাম ছিল Maladie mentale et personnalité। পরবর্তিতে তিনি এই বইটি লিখেননি বলে দাবী করেছিলেন। ফুকো তখন বেশ বুঝতে পারছিলেন যে, শিক্ষকতা তার দ্বারা হবেনা। এই চিন্তা থেকেই ফ্রান্স ...
View Notes - Lecture-1-Themes-in-_42852 from HE 012928 at École Normale Supérieure. Thebiologicalworldandallofitsinherentfeaturesare theproductsof|3billionyearsofchange;changethat:
For example, colicins consume nucleic acids of cells by using several enzymes. To prevent such toxicity, host cells produce ... Sometimes the producer organism needs to create a pore at its own membrane to release such cytolysins, like the case colicins ... Biochim Biophys Acta 947:445-464 James R, Kleanthous C, Moore GR (1996) The biology of E-colicins - paradigms and paradoxes. ...
Colicins Contact-Dependent Growth Inhibition (CDI) systems: CdiA toxins Rhs toxins "Extended" VgrG toxins "Extended" Hcp toxins ... The most studied PT families encompass colicins, toxic effectors of type V secretion systems, some toxic effectors of type VI ... including colicins) in the environment. Polymorphic toxins are bacterial exotoxins which share common features regarding their ...
Polypeptide toxins and many antibacterial peptides, such as colicins or hemolysins, and certain proteins involved in apoptosis ...
Colicins exploit native disorder to gain cell entry: a hitchhikers guide to translocation. Daniel A. Bonsor, Nicola A. Meenan ... Intriguingly, colicins bind TolB using a natively disordered region to mimic the interaction of TolB with Pal (peptidoglycan- ... One such group of toxins are enzymatic E colicins, protein antibiotics produced by Escherichia coli in times of stress. These ... Colicins exploit native disorder to gain cell entry: a hitchhikers guide to translocation ...
... are involved in uptake of group A colicins & infection by filamentous bacteriophages; homologous to exbB protein; amino acid ... from E coli; are involved in uptake of group A colicins & infection by filamentous bacteriophages; homologous to exbB protein; ...
However, the mutated colicins were able to exert their in vivo channel activity only after reduction of their disulfide bonds. ... However, the mutated colicins were able to exert their in vivo channel activity only after reduction of their disulfide bonds. ...
Colicins are a family of bacterial toxins, which kill Escherichia coli cells and other closely related species. Their mode of ... For Group A colicins, translocation requires interaction between the N-terminal domain of the colicin and a series of membrane ... This study also suggests that the interaction with TolB is important for both colicins A and E9. Moreover, a series of ColA ... The immunity protein must be released from the cytotoxic domain of endonuclease E colicins prior to reaching the E. coli ...
Colicins are toxic exoproteins produced by bacteria of colicinogenic strains of Escherichia coli and some related species of ... Synthesis of colicins is coded by genes located on Col plasmids. Until now more than 34 types of colicins have been described, ... Davies J.K., Reeves P.: Genetics of resistance to colicins inEscherichia coli K-12: cross-resistance among colicins of group B. ... Bradley D.E.: Colicins G and H and their host strains.Can. J. Microbiol.37, 751-757 (1991).PubMedGoogle Scholar ...
These hybrid colicins were purified and their properties were studied. All of them were active against sensitive cells, ... Six different hybrid colicins were constructed by recombining various domains of the two pore-forming colicins A and E1. ... Abstract : Six different hybrid colicins were constructed by recombining various domains of the two pore-forming colicins A and ... Individual domains of colicins confer specificity in colicin uptake, in pore-properties and in immunity requirement. Hélène ...
DNA and amino acid sequence analysis of structural and immunity genes of colicins Ia and Ib.. J A Mankovich, C H Hsu, J Konisky ... The two colicins each consist of 626 amino acid residues. Comparison of the two sequences along their lengths revealed that the ... The C-terminal 220 amino acid residues of the colicins are only 60% identical, suggesting that this is the region most likely ... DNA and amino acid sequence analysis of structural and immunity genes of colicins Ia and Ib. ...
Effects of Colicins E1 and K on Cellular Metabolism. Journal of Bacteriology 97, 1 (January 1969): 64-77. Article. 14 Images. ... Effects of Colicins E1 and K on Transport Systems. Journal of Bacteriology 97, 1 (January 1969): 57-63. Article. 7 Images. ... From Phage to Colicins, 1945-1972: Documents. *Biographical Information *Genetics Lessons from Bacteriophage, 1938-1944 *From ... Phage to Colicins, 1945-1972 *Politics, Science, and Social Responsibility *Later Career: Teacher and Administrator, 1972-1991 ...
Colicins E1 and E3 inhibited binding of B12 to the outer membrane B12 receptor sites, and CN-B12 protected cells against these ... Transport of Vitamin B12 in Escherichia coli: Common Receptor Sites for Vitamin B12 and the E Colicins on the Outer Membrane of ... Transport of Vitamin B12 in Escherichia coli: Common Receptor Sites for Vitamin B12 and the E Colicins on the Outer Membrane of ... Transport of Vitamin B12 in Escherichia coli: Common Receptor Sites for Vitamin B12 and the E Colicins on the Outer Membrane of ...
For example, colicins consume nucleic acids of cells by using several enzymes. To prevent such toxicity, host cells produce ... Sometimes the producer organism needs to create a pore at its own membrane to release such cytolysins, like the case colicins ... Biochim Biophys Acta 947:445-464 James R, Kleanthous C, Moore GR (1996) The biology of E-colicins - paradigms and paradoxes. ...
This long distance effect of trypsin suggests that part of the polypeptide chain of the colicins may still be in contact with ... resulted in an immediate arrest of the potassium efflux induced by colicins A and B. The possibility that trypsin may act on a ...
... are identical for the two colicins, arguing against any form of BtuB-induced unfolding. We go on to delineate key features of ... Binding of enzymatic E colicins to the vitamin B12 receptor, BtuB, is the first stage in a cascade of events that culminate in ... Binding of enzymatic E colicins to the vitamin B12 receptor, BtuB, is the first stage in a cascade of events that culminate in ... Cell entry mechanism of enzymatic bacterial colicins: porin recruitment and the thermodynamics of receptor binding. ...
Colicins: prokaryotic killer-pores. Experientia 1990, 46(2), 180-92. * J. Lakey,F. Pattus. A Surprising Omission. Trends in ... Colicins - Prokaryotic Killer-Pores. Experientia 1990, 46(2), 180-192. * F. Pattus,D. Massotte,H. U. Wilmsen,J. Lakey,D. ... Electrostatics and the Unfolding of colicins at the membrane surface. In: J Freer;R Aitken;J.E. Alouf;G Boulnois;P Falmagne;F ... Displacement of OmpF loop 3 is not required for the membrane translocation of colicins N and A in vivo. Febs Letters 1998, 432 ...
Colicins / pharmacology * Fermentation * Humans * Paratyphoid Fever / microbiology * Phylogeny * RNA, Bacterial / ...
We investigated colicins, nonantibiotic antimicrobial proteins produced by certain E. coli strains and active against other ... We demonstrate that most colicins can be expressed at high yields in plants and are fully functional. We show that mixtures of ... We propose plant-produced colicins as an inexpensive food treatment for the broad control of pathogenic E. coli strains. (See ... Broad and efficient control of major foodborne pathogenic strains of Escherichia coli by mixtures of plant-produced colicins. ...
KW - Colicins. KW - Bacteriocins. KW - Colorectal adenoma. KW - Colorectal carcinoma. N2 - Background: Colorectal cancer (CRC) ... keywords = {Escherichia coli; Colicins; Bacteriocins; Colorectal adenoma; Colorectal carcinoma},. language = {eng},. issn = { ... A significantly higher frequency of simultaneous production of colicins and microcins was revealed in the group of patients ... A significantly higher frequency of simultaneous production of colicins and microcins was revealed in the group of patients ...
The TonB protein also interacts with some colicins. Most of these proteins contain a short conserved region at their N terminus ...
Colicins prevent colonization of urinary catheters. J Antimicrob Chemother. 2005;56(2):413-5. https://doi.org/10.1093/jac/ ...
Intrinsically disordered proteins: lessons from colicins.. Hecht O, Macdonald C, Moore GR. ...
Colicins / metabolism*. Escherichia coli / drug effects. Molecular Weight. Peptide Fragments / analysis, pharmacology. Protein ... 0/Amino Acids; 0/Carboxylic Acids; 0/Colicins; 0/Peptide Fragments; 0/RNA, Ribosomal; 151-21-3/Sodium Dodecyl Sulfate; EC 3.4. ...
"Colicins"and "Bacteriocins" Encyclopedia of Molecular Biology and Molecular Medicine.. 3. "Glucose Oxidase" Toyobo Enzymes ( ...
Bacteriocins (colicins, microcins, lantibiotics…). Archaeocins. Biocontrol approach to microbial invasions (probiotics, lactic ...
Colicins Contact-Dependent Growth Inhibition (CDI) systems: CdiA toxins Rhs toxins "Extended" VgrG toxins "Extended" Hcp toxins ... The most studied PT families encompass colicins, toxic effectors of type V secretion systems, some toxic effectors of type VI ... including colicins) in the environment. Polymorphic toxins are bacterial exotoxins which share common features regarding their ...
Colicins E4, E5, E6 and A and properties of btuB+ colicinogenic transconjugants. ...
Binding of E colicins to BtuB is competitively inhibited by CNCbl (11). The 76-aa receptor-binding R domain of colicin E9 binds ... BtuB is receptor for the A and E colicins, the entry of which requires instead the Tol system (reviewed in refs. 9 and 10). ... TonB-dependent transporters are also receptors for lethal agents including phages, microcins, and colicins. FepA and FhuA are ... Colicins are elongated proteins, the T, R, and C domains of which mediate OM translocation, receptor binding, and lethal ...
The work he did on colicins was fascinating. He studied three different colicins and discovered that they killed target ... Nomura feared that the ribosome field would be a rat race and believed that work on colicins would be the secret to a tranquil ... Although Masayasu had done some work on ribosomes before coming to Madison, his early work in Madison focused on colicins - ... and I think its fair to say that colicins were at least warm, if not rat-race hot, in the early 1960s, thanks to the work of ...
29.Konisky, J., Colicins and other bacteriocins with established modes of action. Annu Rev Microbiol, 1982. 36: p. 125-44.. 30. ... 71.Fredericq, P., Colicins. Annu Rev Microbiol, 1957. 11: p. 7-22.. 72.Sambrook, J., et al., SDS-polyacrylamide gel ...
Project: Reconstructing the Ancestral Killing Breadth of Colicins. Robert Dorit (Biology, Smith College) ...
From Phage to Colicins, 1945-1972. *Politics, Science, and Social Responsibility. *Later Career: Teacher and Administrator, ...
word of the day: colicins!. http://www.popsci.com/scienti....ur-food ... word of the day: colicins!. http://www.popsci.com/scienti....ur-food. ... word of the day: colicins!. http://www.popsci.com/scienti....ur-food. ...
... and these lipoprotein-encoding genes are co-expressed along with the colicins. For group B colicins, as is the case for ... Similarly, colicins also depend on a SOS system to initiate their expression, mediated by LexA. This protein controls two ... van Raay, K., and Kerr, B. (2016). Toxins go viral: phage-encoded lysis releases group B colicins. Environ. Microbiol. 18, 1308 ... Pseudomonas bacteriocins, a lysis gene is lacking (Cascales et al., 2007). However, for these colicins in particular it was ...
  • However, the mutated colicins were able to exert their in vivo channel activity only after reduction of their disulfide bonds. (unl.edu)
  • Plant-produced Colicins, Colicin-like Bacteriocins, and bacteriophage Endolysins are being developed by NOMAD as inexpensive food additives and food processing aids for the broad control of pathogenic bacteria (E. coli, Salmonella, Listeria and Clostridium) in food products. (pressebox.com)
  • It also discusses the molecular evolution of colicins and colicin-like bacteriocins. (opal-libraries.org)
  • It discusses the molecular evolution of colicins and colicin-like bacteriocins, and provides a contemporary overview of archaeocins, bacteriocin-like antimicrobials produced by archaebacteria. (epa.gov)
  • Colicins are toxic exoproteins produced by bacteria of colicinogenic strains of Escherichia coli and some related species of Enterobacteriaceae , during the growth of their cultures. (springer.com)
  • Although Masayasu had done some work on ribosomes before coming to Madison, his early work in Madison focused on colicins - bacteriocidal products produced by bacteria. (asbmb.org)
  • He studied three different colicins and discovered that they killed target bacteria by three different mechanisms (1). (asbmb.org)
  • Bacteria have evolved several systems to outcompete their neighbors by poisoning them through a contact-dependent killing (including effectors of type V and VI secretion systems) or the release of soluble toxins (including colicins) in the environment. (wikipedia.org)
  • Colicins are organized into three domains, each one involved in a different step of the process of killing sensitive bacteria. (umass.edu)
  • One class of plasmids, colicinogenic (or Col ) factors, determines the production of proteins called colicins, which have antibiotic activity and can kill other bacteria. (britannica.com)
  • In the project " Molecular studies on selected colicin types (MOLCOL)", we study colicins, a class of bacterial proteins that are produced by some bacterial strains to kill other bacteria. (uio.no)
  • This is in contrast to the action of colicins or antibiotics that are secreted by bacteria into their environment as inhibitors of neighboring microorganisms. (sciencemag.org)
  • A team of scientists is genetically engineering plants to produce antimicrobial proteins known as colicins, which can then be extracted and applied to contaminated meat and produce to kill E. coli bacteria. (rssl.com)
  • One of the authors of the study added that colicins are 50 times more active against bacteria than normal antibiotics. (rssl.com)
  • To conclude, plant-produced colicins could be effectively used for the broad control of pathogenic E. coli in both plant and animal-based food products, and research team members are planning to extend their process to other bacteria such as Salmonella . (rssl.com)
  • We want to find out exactly how the colicin sneaks its way in and out of OmpF and to see if this mechanism occurs in colicins that target pathogenic bacteria", said Professor Kleanthous. (technologynetworks.com)
  • Six different hybrid colicins were constructed by recombining various domains of the two pore-forming colicins A and E1. (archives-ouvertes.fr)
  • This exchange has especially occurred within the class of colicins and yielded a repertoire of 11 pore-forming colicins. (portlandpress.com)
  • 1] "Strong function-related homology between the pore-forming colicins K and 5. (tcdb.org)
  • We investigated colicins, nonantibiotic antimicrobial proteins produced by certain E. coli strains and active against other strains of the species, as potential pathogen control agents. (pnas.org)
  • Colicins are proteins produced by and toxic for some strains of Escherichia coli. (umass.edu)
  • Colicins are toxic proteins produced by Escherichia coli that target and kill other E. coli cells. (washington.edu)
  • Colicins are proteins produced by some strains of Escherichia coli to kill competitors belonging to the same species. (portlandpress.com)
  • Colicins are naturally produced nonantibiotic antimicrobial proteins, produced by E. coli strains that kill or inhibit growth of other competing E. coli strains. (rssl.com)
  • Colicins are toxic proteins produced by Escherichia coli that must cross the membrane to exert their activity. (ac.be)
  • Binding of enzymatic E colicins to the vitamin B12 receptor, BtuB, is the first stage in a cascade of events that culminate in the translocation of the cytotoxic nuclease into the Escherichia coli cytoplasm and release of its tightly bound immunity protein. (ox.ac.uk)
  • Molecular structure and immunity specifity of colicin E6, an evolutionary intermediate between E-group colicins and cloacin DF13. (springer.com)
  • Individual domains of colicins confer specificity in colicin uptake, in pore-properties and in immunity requirement. (archives-ouvertes.fr)
  • The addition of trypsin, which has access neither to the periplasmic space nor to the cytoplasmic membrane, resulted in an immediate arrest of the potassium efflux induced by colicins A and B. The possibility that trypsin may act on a bacterial component required for colicin reception and/or translocation was ruled out. (nih.gov)
  • Chapter 2: Colicin mutation confers resistance to colicins in Escherichia coli. (washington.edu)
  • The crystal structure of the TolB box of colicin A in complex with TolB reveals important differences in the recruitment of the common TolB translocation portal used by group A colicins. (nih.gov)
  • Sequence analysis of the bacteriocin gene revealed homology to genes of alveicin A and alveicin B, colicins Ia and Ib, S-type pyocin and colicin E1. (muni.cz)
  • Cell entry mechanism of enzymatic bacterial colicins: porin recruitment and the thermodynamics of receptor binding. (ox.ac.uk)
  • Structural and mechanistic basis of immunity toward endonuclease colicins. (embl.de)
  • A significantly higher frequency of simultaneous production of colicins and microcins was revealed in the group of patients with CRC, when compared to patients with CRA, p = 0.031. (muni.cz)
  • TonB-dependent transporters are also receptors for lethal agents including phages, microcins, and colicins. (pnas.org)
  • This region is the site of mutations, such as the substitution of Pro for Leu-8 or Val-10 in BtuB, which result in loss of Cbl transport but do not affect Cbl binding or entry of the TonB-independent phage BF23 and E colicins ( 13 , 14 ). (pnas.org)
  • DNA and amino acid sequence analysis of structural and immunity genes of colicins Ia and Ib. (asm.org)
  • The C-terminal 220 amino acid residues of the colicins are only 60% identical, suggesting that this is the region most likely recognized by their cognate immunity proteins. (asm.org)
  • FepA and FhuA are receptors for some group B colicins, the entry of which requires the TonB system. (pnas.org)
  • Synthesis of colicins is coded by genes located on Col plasmids. (springer.com)
  • Colicins Ia, Ib and E1, and microcin V, were identified among plasmids that also contained resistance and virulence genes. (rug.nl)
  • The active sites of these nucleases are strongly conserved, and the ability to tolerate a mutation in the conserved catalytic site appears high in some studies of colicins resulting in measurable activity, but reports in other enzymes containing the motif show a loss of DNA cleavage activity [8] . (proteopedia.org)
  • Plasmid-encoded enzymes, the colicins, are involved in the cleavage of the anticodons of specific tRNAs in E. coli ( 36 , 43 ), resulting in the production of tRNA fragments. (asm.org)
  • PresseBox) ( München , 2017-05-30 ) NOMAD Bioscience received a formal 'no questions' letter from the US Food and Drug Administration (FDA) in response to NOMAD's GRAS notice GRN 676 describing use of Colicins as 'Food Processing Aids' for control of major foodborne pathogenic strains of Escherichia coli on beef, pork and lamb meats. (pressebox.com)
  • The proteins are extremely toxic, so the researchers decided to engineer the aforementioned plants since colicins are not as toxic to plant cells. (rssl.com)
  • In this paper, evidence is presented that these B 12 receptor sites also function as the receptors for the E colicins, and that there is competition between B 12 and the E colicins for occupancy of these sites. (asm.org)
  • Colicins E1 and E3 inhibited binding of B 12 to the outer membrane B 12 receptor sites, and CN-B 12 protected cells against these colicins. (asm.org)
  • Contrary to expectation, the thermodynamics of receptor binding, characterized by large negative values for TDeltaS, are identical for the two colicins, arguing against any form of BtuB-induced unfolding. (ox.ac.uk)
  • BtuB is receptor for the A and E colicins, the entry of which requires instead the Tol system (reviewed in refs. (pnas.org)
  • Comparison of sequences among many colicins has allowed the identification of a putative receptor-binding domain. (rcsb.org)
  • Colicins exert their lethal action by first binding to specific receptors, which are outer membrane proteins used for the entry of specific nutrients. (umass.edu)
  • Colicins then reach their lethal target and act either by forming a voltage-dependent channel into the inner membrane or by using their endonuclease activity on DNA, rRNA, or tRNA. (umass.edu)
  • Binding of E colicins to BtuB is competitively inhibited by CNCbl ( 11 ). (pnas.org)
  • We show that mixtures of colicins applied at low concentrations are highly and broadly active against all major pathogenic E. coli strains of concern for foodborne illness. (pnas.org)
  • We propose plant-produced colicins as an inexpensive food treatment for the broad control of pathogenic E. coli strains. (pnas.org)
  • This review explores features of the origin and evolution of colicins in Escherichia coli. (umass.edu)
  • In Escherichia coli , more than 20 different colicins are known to target various structures in the cell. (portlandpress.com)
  • The group A colicins and the DNA of many single-stranded filamentous bacteriophage are able to use combinations of the Tol proteins to gain entrance into or across the membrane of Escherichia coli. (pnas.org)
  • In the study, the researchers sprayed E. coli -laced pork steaks with a mixture of two types of colicins and found significant reductions in E. coli after just one hour. (rssl.com)
  • The structures of some colicins are known at the atomic level and are discussed. (umass.edu)
  • Because the efficacy of antimicrobials applied to US meats is under the jurisdiction of the US Department of Agriculture (USDA), the USDA's Food Safety and Inspection Service (FSIS) co-reviewed with FDA NOMAD's data package and concluded that Colicins met USDA suitability criteria for use on meats. (pressebox.com)
  • FDA and USDA accepted NOMAD's Colicins as first-in-class GRAS natural non-antibiotic antimicrobials for treating fruits & vegetables (GRN 593) and meat products (GRN 676). (pressebox.com)
  • The classification of colicins is based on differences in the molecular events of these three steps. (springer.com)
  • Comparison of the two sequences along their lengths revealed that the two colicins are nearly identical in the N-terminal 426 amino acid residues. (asm.org)
  • The two colicins each consist of 626 amino acid residues. (asm.org)
  • In contrast with other colicins, folding of Cma depends on the presence of the periplasmic FkpA chaperone, which is essential for activity [ 7 - 10 ]. (portlandpress.com)
  • We demonstrate that most colicins can be expressed at high yields in plants and are fully functional. (pnas.org)
  • This promised to be a rich field of investigation, and I think it's fair to say that colicins were at least warm, if not rat-race hot, in the early 1960s, thanks to the work of the Nomura lab. (asbmb.org)
  • Dissertation: "Colicins - a Sound Antimicrobial Approach for the Prevention of Catheter-Associated Urinary Tract Infections. (umass.edu)
  • This is followed by a single long ( approximately 74 A) helix that connects the N-terminal domain to the C-terminal pore-forming domain, which is composed of 10 alpha-helices arranged in a bundle-type structure, similar to the pore-forming domains of other colicins. (rcsb.org)
  • In the current study published in the Proceedings of the National Academy of Sciences, the researchers engineered tobacco, leafy beets, spinach, chicory and lettuce to produce colicins. (rssl.com)
  • In vitro assessment of the cytotoxicity of nisin, pediocin, and selected colicins on simian virus 40-transfected human colon and Vero monkey kidney cells with trypan blue staining viability assays. (nature.com)
  • Colicins and their potential in cancer treatment. (mpg.de)