Infection of Escherichia coli with bacteriophages

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100063767 ◽

1969 ◽

Vol 27 ◽

pp. 370-371

Author(s):

Manfred E. Bayer

Keyword(s):

Escherichia Coli ◽

Nucleic Acid ◽

Cell Surface ◽

Virus Type ◽

Infection Process ◽

Adsorption Site ◽

The Other ◽

Specific Receptors ◽

Bacterial Receptors

The first step in the infection of a bacterium by a virus consists of a collision between cell and bacteriophage. The presence of virus-specific receptors on the cell surface will trigger a number of events leading eventually to release of the phage nucleic acid. The execution of the various "steps" in the infection process varies from one virus-type to the other, depending on the anatomy of the virus. Small viruses like ØX 174 and MS2 adsorb directly with their capsid to the bacterial receptors, while other phages possess attachment organelles of varying complexity. In bacteriophages T3 (Fig. 1) and T7 the small conical processes of their heads point toward the adsorption site; a welldefined baseplate is attached to the head of P22; heads without baseplates are not infective.

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Suppression by the ColV,I-K94 plasmid of inhibitor sensitivities in ompA mutants of Escherichia coli

Canadian Journal of Microbiology ◽

10.1139/m88-029 ◽

1988 ◽

Vol 34 (2) ◽

pp. 148-156 ◽

Cited By ~ 3

Author(s):

Claudia F. L. Reakes ◽

Caroline M. M. Deeney ◽

Margaret Goodson ◽

Robin J. Rowbury

Keyword(s):

Escherichia Coli ◽

Cell Surface ◽

Fusidic Acid ◽

Polymyxin B ◽

Aminoglycoside Antibiotics ◽

The Other ◽

Gene Products ◽

Escherichia Coli K12 ◽

Increased Sensitivity ◽

Large Plasmids

A series of ompA mutants derived from Escherichia coli K12 strains showed increased sensitivity (compared with the ompA+ parents) to aminoglycoside antibiotics and to other cationic agents including polymyxin B. One tested mutant also showed increased sensitivity to nafcillin and fusidic acid, but not to the hydrophilic ampicillin. All these inhibitor sensitivities in the ompA mutants were suppressed by ColV, I-K94 and by certain other ColV plasmids, but not by any of the other tested large plasmids. Suppression correlated with the production of the VmpA protein, but transfer and colicin components were not needed for suppression. Further comparison of the ompA and vmpA genes and their products was made and it indicated that there is little if any homology between the genes, that the synthesis of their products is regulated by quite different mechanisms, and that regions of these gene products exposed at the cell surface show different susceptibility to protease attack after denaturation.

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Characterization of enteroaggregative Escherichia coli isolated from outbreaks of diarrhoeal disease in England

Epidemiology and Infection ◽

10.1017/s0950268899002976 ◽

1999 ◽

Vol 123 (3) ◽

pp. 413-421 ◽

Cited By ~ 15

Author(s):

J. SPENCER ◽

H. R. SMITH ◽

H. CHART

Keyword(s):

Escherichia Coli ◽

Cell Surface ◽

Surface Charge ◽

Surface Properties ◽

Diarrhoeal Disease ◽

The Other ◽

Diverse Range ◽

Cell Surface Properties ◽

Protein Map

Twenty-two strains of enteroaggregative Escherichia coli (EAggEC), isolated from four outbreaks of diarrhoeal disease in England, were examined for a range of phenotypic attributes including the ability to produce fimbriae, haemolysins and siderophores, and cell-surface properties such as surface charge and hydrophobicity. Strains of EAggEC isolated from two of these outbreaks belonged to a diverse range of serotypes and were heterogeneous in phenotype. Strains of EAggEC isolated from the other two outbreaks belonged predominantly to serotypes O86[ratio ]H34 and O98[ratio ]H-, respectively. Only two strains expressed fimbriae and two strains produced an 18 kDa membrane associated protein (MAP), suggesting that EAggEC express a range of adhesion mechanisms to produce the cell arrangement recognized as the ‘stacked brick’ formation. The possible explanation for the diversity of EAggEC serotypes is discussed.

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THE EFFECT OF ACTINOBOLIN ON NUCLEIC ACID AND PROTEIN SYNTHESIS IN ESCHERICHIA COLI

Canadian Journal of Microbiology ◽

10.1139/m66-074 ◽

1966 ◽

Vol 12 (3) ◽

pp. 515-520 ◽

Cited By ~ 6

Author(s):

D. E. Hunt ◽

R. F. Pittillo ◽

E. P. Johnson ◽

F. C. Moncrief

Keyword(s):

Escherichia Coli ◽

Protein Synthesis ◽

Amino Acid ◽

Nucleic Acid ◽

Mechanism Of Action ◽

Rna Synthesis ◽

The Other ◽

Cross Resistance ◽

Inhibition Of Protein Synthesis

Actinobolin inhibits protein synthesis in Escherichia coli. When the antibiotic is added to a culture at the time of inoculation, RNA synthesis is also inhibited. Inhibition of RNA synthesis appears to be a consequence of inhibition of protein synthesis. Cross-resistance experiments suggest that the mechanism of action of actinobolin differs from that of the other inhibitors of protein synthesis, chloramphenicol and sparsomycin. Phenylalanine prevents the action of actinobolin provided the amino acid and antibiotic are added simultaneously; this effect is not observed if the phenylalanine is added 1 hour after the addition of the antibiotic. Evidence is presented that the mechanism by which phenylalanine prevents inhibition by actinobolin differs from that which has been suggested for azaserine and p-fluorophenylalanine.

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Glycotargeting: Influence of the Sugar Moiety on Both the Uptake and the Intracellular Trafficking of Nucleic Acid Carried by Glycosylated Polymers

Bioscience Reports ◽

10.1023/a:1020114611517 ◽

1999 ◽

Vol 19 (2) ◽

pp. 125-132 ◽

Cited By ~ 27

Author(s):

Michel Monsigny ◽

Patrick Midoux ◽

Roger Mayer ◽

Annie-Claude Roche

Keyword(s):

Nucleic Acid ◽

Cell Surface ◽

Nucleic Acids ◽

Intracellular Trafficking ◽

Surface Membrane ◽

The Other ◽

Cell Surface Membrane ◽

Sugar Moiety ◽

Other Hand ◽

The One

Nucleic acids (plasmids as well as oligonucleotides) used to specifically express or modulate the expression of a gene, must reach the cytosol and/or the nucleus. Several systems have been developed to increase their uptake and their efficiency. Glycosylated polylysines have been shown to specifically help nucleic acids to be taken up in cells expressing a given cell surface membrane lectin. However, it appeared that the efficiency of the imported nucleic acid was not directly related to the extent of the uptake. Indeed, some glycosylated polylysines bearing sugar moities which are poor ligands of the cell surface lectins of a given cell were found to be more efficient than those bearing better sugar ligands. The interpretation of this paradoxal result is discussed with regards to the nature of the compartment allowing the nucleic acid to cross the membrane and to be delivered in the cytosol on the one hand, and to the presence of intracellular lectins on the other hand.

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The Nature of the Intramembrane Particle

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600003020 ◽

1980 ◽

Vol 38 ◽

pp. 688-691

Author(s):

A.J. Verkleij

Keyword(s):

Escherichia Coli ◽

Tight Junction ◽

Gap Junction ◽

The Other ◽

Fracture Face ◽

Band 3 Protein ◽

Satisfactory Explanation ◽

Freeze Fracturing ◽

Intramembrane Particle ◽

Luminal Membrane

Freeze-fracturing splits membranes into two helves, thus allowing an examination of the membrane interior. The 5-10 rm particles visible on both monolayers are widely assumed to be proteinaceous in nature. Most membranes do not reveal impressions complementary to particles on the opposite fracture face, if the membranes are fractured under conditions without etching. Even if it is considered that shadowing, contamination or fracturing itself might obscure complementary pits', there is no satisfactory explanation why under similar physical circimstances matching halves of other membranes can be visualized. A prominent example of uncomplementarity is found in the erythrocyte manbrane. It is wall established that band 3 protein and possibly glycophorin represents these nonccmplanentary particles. On the other hand a number of membrane types show pits opposite the particles. Scme well known examples are the ";gap junction',"; tight junction, the luminal membrane of the bladder epithelial cells and the outer membrane of Escherichia coli.

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