The Role of the envM Genes of Escherichia coli and Salmonella typhimurium in Cell Membrane Biosynthesis

1993 ◽  
pp. 197-203
Author(s):  
Friederike Turnowsky ◽  
Helmut Bergler ◽  
Elisabeth Ingolic
Keyword(s):  
Escherichia Coli ◽  
Cell Membrane ◽  
Salmonella Typhimurium ◽  
Membrane Biosynthesis

Über die Zellmembran von Escherichia Coli B

1954 ◽  
Vol 9 (6) ◽  
pp. 398-406 ◽  
Author(s):  
Wolfhard Weidel ◽  
Gebhard Koch ◽  
Friedrich Lohss
Keyword(s):  
Escherichia Coli ◽  
Chemical Analysis ◽  
Cell Membrane ◽  
B Cell ◽  
Dry Weight ◽  
Shigella Sonnei ◽  
Receptor Activity ◽  
Escherichia Coli B

Dissociation in 90% phenol uncovers a layer of the Coli B-cell membrane showing the typical antiviral specificity of the receptor for phages T3, T4 and T7. Chemical analysis proved glucose, glucosamine and a yet unknown carbohydrate, probably a heptose, to be components of the receptor material, which amounts to about 13% of the dry weight of the whole membrane.Analogous material obtained from the membrane of B/3,4,7, a B-mutant resistant against phages T3, T4 and T7, has no activity against these phages and contains glucosamine and small amounts of glucose, but no heptose.In view of similar findings of Jesaitis and Goebel with T3,4,7 - receptor material from Shigella Sonnei, the rôle of the heptose as a characteristic and functionally indispensable component of lipocarbohydrates with receptor activity against T3, T4 and T7 is discussed.

MERODIPLOIDY IN ESCHERICHIA COLI-SALMONELLA TYPHIMURIUM CROSSES: THE ROLE OF UNEQUAL RECOMBINATION BETWEEN RIBOSOMAL RNA GENES

Genetics ◽  
1985 ◽  
Vol 110 (3) ◽  
pp. 365-380
Author(s):  
Andreas F Lehner ◽  
C W Hill
Keyword(s):  
Escherichia Coli ◽  
Salmonella Typhimurium ◽  
E Coli ◽  
Unequal Recombination ◽  
Oric Region ◽  
Prime Factors ◽  
Transfer Origin ◽  
Rrn Operons ◽  
Prime 2

ABSTRACT Previous workers have shown that intergeneric crosses between Salmonella typhimurium and Escherichia coli produce a high proportion of merodiploid recombinants among the viable progeny. We have examined the unequal crossover event that was responsible for a number of intergeneric merodiploids. The merodiploids that we studied were all heterozygous for the metB–argH interval and were the products of intergeneric conjugal crosses. We found that when the S. typhimurium donor had its transfer origin closely linked to metB and argH, all recombinants examined were merodiploid, and they generally arose as F-prime factors. Many of these F-prime factors had been created by recombination between flanking rrn genes in the donor. When the S. typhimurium Hfr transfer origin was more distant from the selected markers, quite different results were obtained. (1) Depending on the donor, 19–47% of the recombinants that acquired the donor argH  + or metB  + genes were merodiploid for these loci, but none of the recombinants were F-prime. (2) A majority of the merodiploids had a novel (nonparental) rrn gene, indicating that unequal recombination between nonidentical rrn genes was a prevalent mechanism for establishing the merodiploidy. (3) Both tandem and nontandem duplications were found. (4) Some of the merodiploids duplicated E. coli genes in addition to acquiring S. typhimurium genes. (5) Some merodiploids contained the oriC region from each parent. Of a total of 118 intergeneric merodiploids characterized from all donors, 48 different genotypes were observed, and 38 of the 48 had one or more nonparental rrn operons.

scholarly journals Growth of Salmonella typhimurium SL5319 and Escherichia coli F-18 in mouse cecal mucus: role of peptides and iron

1990 ◽  
Vol 7 (2-3) ◽  
pp. 229-239 ◽  
Author(s):  
David P. Franklin ◽  
David C. Laux ◽  
Taffy J. Williams ◽  
Michael C. Falk ◽  
Paul S. Cohen
Keyword(s):  
Escherichia Coli ◽  
Salmonella Typhimurium

scholarly journals Role of Lipopolysaccharide and Complement in Susceptibility of Escherichia coli and Salmonella typhimurium to Non-immune Serum

Microbiology ◽  
1988 ◽  
Vol 134 (4) ◽  
pp. 1009-1016 ◽  
Author(s):  
J. M. Tomas ◽  
B. Ciurana ◽  
V. J. Benedi ◽  
A. Juarez
Keyword(s):  
Escherichia Coli ◽  
Salmonella Typhimurium ◽  
Immune Serum

scholarly journals Role of the Lipopolysaccharide-CD14 Complex for the Activity of Hemolysin from Uropathogenic Escherichia coli

2006 ◽  
Vol 75 (2) ◽  
pp. 997-1004 ◽  
Author(s):  
Lisa E. Månsson ◽  
Peter Kjäll ◽  
Shahaireen Pellett ◽  
Gábor Nagy ◽  
Rodney A. Welch ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Cell Membrane ◽  
Signal Transduction Pathway ◽  
Recognition System ◽  
Small Gtpase ◽  
Host Cell Membrane ◽  
Common View ◽  
Experimental Artifact ◽  
Intracellular Ca

ABSTRACT Bacterial pathogens produce a variety of exotoxins, which often become associated with the bacterial outer membrane component lipopolysaccharide (LPS) during their secretion. LPS is a potent proinflammatory mediator; however, it is not known whether LPS contributes to cell signaling induced by those microbial components to which it is attached. This is partly due to the common view that LPS present in bacterial component preparations is an experimental artifact. The Escherichia coli exotoxin hemolysin (Hly) is a known inducer of proinflammatory signaling in epithelial cells, and the signal transduction pathway involves fluctuation of the intracellular-Ca2+ concentration. Since LPS is known to interact with Hly, we investigated whether it is required as a cofactor for the activity of Hly. We found that the LPS/Hly complex exploits the CD14/LPS-binding protein recognition system to bring Hly to the cell membrane, where intracellular-Ca2+ signaling is initiated via specific activation of the small GTPase RhoA. Hly-induced Ca2+ signaling was found to occur independently of the LPS receptor TLR4, suggesting that the role of LPS/CD14 is to deliver Hly to the cell membrane. In contrast, the cytolytic effect triggered by exposure of cells to high Hly concentrations occurs independently of LPS/CD14. Collectively, our data reveal a novel molecular mechanism for toxin delivery in bacterial pathogenesis, where LPS-associated microbial compounds are targeted to the host cell membrane as a consequence of their association with LPS.

scholarly journals Pathologic and microbiologic aspects of pet psittacine infected by Escherichia coli and Salmonella Typhimurium

2017 ◽  
Vol 37 (4) ◽  
pp. 379-384
Author(s):  
Raul A.S. Siqueira ◽  
William C. Maciel ◽  
Ruben H. Vasconcelos ◽  
Windleyanne G.A. Bezerra ◽  
Elisângela S. Lopes ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Multidrug Resistance ◽  
Salmonella Typhimurium ◽  
Antimicrobial Susceptibility ◽  
Inflammatory Infiltrate ◽  
State University ◽  
Antimicrobial Susceptibility Test ◽  
Salmonella Spp ◽  
E Coli

ABSTRACT: The role of Escherichia coli in healthy microbiota of psittacine is controversial, and the presence of Salmonella sp. indicates possible disease. Therefore, this study aimed to identify the presence of E. coli and Salmonella spp. in a psittacine pet that died in Fortaleza, Brazil, correlating pathogenicity aspects of the isolates through the evaluation of lesions and antimicrobial susceptibility. Psittacine pets sent to the Laboratory of Ornithological Studies, State University of Ceará, that died in 2014 and 2015 were necropsied. Fragments of liver, kidneys, intestine, lung, heart, spleen and brain were collected for microbiological and histopathological analyses. Scores were attributed to lesions and isolated strains submitted to antimicrobial susceptibility test. From the seventy necropsied birds, nineteen were positive for E. coli and one for Salmonella Typhimurium. Congestive lesions and lymphoplasmocitic inflammatory infiltrate were observed varying from light to moderate and were the main findings. In the analyzed strains, multidrug resistance against different groups of antibiotics was observed. In conclusion, according to the results, E. coli strains and the Salmonella Typhimurium isolate produced significant lesions in the psittacine pets, and multidrug resistance may hinder treatments with antibiotics used in avian pet medicine.

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