scholarly journals Sensitivity of Escherichia albertii, a Potential Food-Borne Pathogen, to Food Preservation Treatments

2007 ◽  
Vol 73 (13) ◽  
pp. 4351-4353 ◽  
Author(s):  
Manan Sharma ◽  
Kalmia E. Kniel ◽  
Alexandra Derevianko ◽  
Jason Ling ◽  
Arvind A. Bhagwat
Keyword(s):  
Diarrheal Disease ◽  
Food Preservation ◽  
Wild Type ◽  
E Coli ◽  
Acid Ph ◽  
Food Borne ◽  
Potential Food

ABSTRACT Escherichia albertii is a potential food-borne pathogen because of its documented ability to cause diarrheal disease by producing attachment and effacement lesions. Its tolerances to heat (56°C), acid (pH 3.0), and pressure (500 MPa [5 min]) were evaluated and found to be significantly less than those of wild-type E. coli O157:H7.

EnteropathogenicEscherichia coliinhibits butyrate uptake in Caco-2 cells by altering the apical membrane MCT1 level

2006 ◽  
Vol 290 (1) ◽  
pp. G30-G35 ◽  
Author(s):  
Alip Borthakur ◽  
Ravinder K. Gill ◽  
Kim Hodges ◽  
Krishnamurthy Ramaswamy ◽  
Gail Hecht ◽  
...  
Keyword(s):  
Surface Expression ◽  
Monocarboxylate Transporter ◽  
Wild Type ◽  
Infantile Diarrhea ◽  
Monocarboxylate Transporter 1 ◽  
E Coli ◽  
Food Borne ◽  
Mutant Strains ◽  
Genes Encoding ◽  
Fatty Acid Absorption

Enteropathogenic Escherichia coli (EPEC), a food-borne human pathogen, is responsible for infantile diarrhea, especially in developing countries. The pathophysiology of EPEC-induced diarrhea, however, is not completely understood. Our recent studies showed modulation of Na+/H+and Cl−/HCO3−exchange activities in Caco-2 cells in response to EPEC infection. We hypothesized that intestinal short-chain fatty acid absorption mediated by monocarboxylate transporter 1 (MCT1) might also be altered by EPEC infection. The aim of the current studies was to examine the effect of EPEC infection on butyrate uptake. Caco-2 cells were infected with wild-type EPEC, various mutant strains, or nonpathogenic E. coli HS4, and [14C]butyrate uptake was determined. EPEC, but not nonpathogenic E. coli, significantly decreased butyrate uptake. Infection of cells with strains harboring mutations in escN, which encodes a putative ATPase for the EPEC type III secretion system (TTSS), or in the espA, espB, or espD genes encoding structural components of the TTSS, had no effect on butyrate uptake, indicating the TTSS dependence. On the other hand, strains with mutations in the effector protein genes espF, espG, espH, and map inhibited butyrate uptake, similar to the wild-type EPEC. Surface expression of MCT1 decreased considerably after EPEC but not after nonpathogenic E. coli infection. In conclusion, our studies demonstrate inhibition of MCT1-mediated butyrate uptake in Caco-2 cells in response to EPEC infection. This inhibition was dependent on a functional TTSS and the structural proteins EspA, -B, and -D of the translocation apparatus.

scholarly journals Comparative Genomic Indexing Reveals the Phylogenomics of Escherichia coli Pathogens

2003 ◽  
Vol 71 (8) ◽  
pp. 4674-4683 ◽  
Author(s):  
Muna F. Anjum ◽  
Sacha Lucchini ◽  
Arthur Thompson ◽  
Jay C. D. Hinton ◽  
Martin J. Woodward
Keyword(s):  
Escherichia Coli ◽  
Diarrheal Disease ◽  
Comparative Genomic ◽  
E Coli ◽  
Food Borne ◽  
Typing Methods ◽  
K 12 ◽  
Genomic Indexing ◽  
Core Genes ◽  
Genomic Similarity

ABSTRACT The Escherichia coli O26 serogroup includes important food-borne pathogens associated with human and animal diarrheal disease. Current typing methods have revealed great genetic heterogeneity within the O26 group; the data are often inconsistent and focus only on verotoxin (VT)-positive O26 isolates. To improve current understanding of diversity within this serogroup, the genomic relatedness of VT-positive and -negative O26 strains was assessed by comparative genomic indexing. Our results clearly demonstrate that irrespective of virulence characteristics and pathotype designation, the O26 strains show greater genomic similarity to each other than to any other strain included in this study. Our data suggest that enteropathogenic and VT-expressing E. coli O26 strains represent the same clonal lineage and that VT-expressing E. coli O26 strains have gained additional virulence characteristics. Using this approach, we established the core genes which are central to the E. coli species and identified regions of variation from the E. coli K-12 chromosomal backbone.

scholarly journals High-Pressure-Induced Sublethal Injuries of Food Pathogens—Microscopic Assessment

Foods ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2940
Author(s):  
Justyna Nasiłowska ◽  
Aleksandra Kocot ◽  
Paulina Natalia Osuchowska ◽  
Barbara Sokołowska
Keyword(s):  
Electron Microscopy ◽  
Type Strain ◽  
Wild Type Strain ◽  
Physiological State ◽  
Fluorescent Microscopy ◽  
Food Preservation ◽  
Epifluorescence Microscopy ◽  
Wild Type ◽  
E Coli ◽  
Percentage Ratio

High Hydrostatic Pressure (HHP) technology is considered an alternative method of food preservation. Nevertheless, the current dogma is that HHP might be insufficient to preserve food lastingly against some pathogens. Incompletely damaged cells can resuscitate under favorable conditions, and they may proliferate in food during storage. This study was undertaken to characterize the extent of sublethal injuries induced by HHP (300–500 MPa) on Escherichia coli and Listeria inncua strains. The morphological changes were evaluated using microscopy methods such as Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Epifluorescence Microscopy (EFM). The overall assessment of the physiological state of tested bacteria through TEM and SEM showed that the action of pressure on the structure of the bacterial membrane was almost minor or unnoticeable, beyond the L. innocua wild-type strain. However, alterations were observed in subcellular structures such as the cytoplasm and nucleoid for both L. innocua and E. coli strains. More significant changes after the HHP of internal structures were reported in the case of wild-type strains isolated from raw juice. Extreme condensation of the cytoplasm was observed, while the outline of cells was intact. The percentage ratio between alive and injured cells in the population was assessed by fluorescent microscopy. The results of HHP-treated samples showed a heterogeneous population, and red cell aggregates were observed. The percentage ratio of live and dead cells (L/D) in the L. innocua collection strain population was higher than in the case of the wild-type strain (69%/31% and 55%/45%, respectively). In turn, E. coli populations were characterized with a similar L/D ratio. Half of the cells in the populations were distinguished as visibly fluorescing red. The results obtained in this study confirmed sublethal HHP reaction on pathogens cells.

scholarly journals TheEscherichia coliO157:H7 Carbon Starvation-Inducible Lipoprotein Slp Contributes to Initial AdherenceIn Vitrovia the Human Polymeric Immunoglobulin Receptor

2018 ◽  
Author(s):  
Christine Fedorchuk ◽  
Indira T. Kudva ◽  
Subhashinie Kariyawasam
Keyword(s):  
Escherichia Coli ◽  
Immunofluorescence Microscopy ◽  
Polymeric Immunoglobulin Receptor ◽  
Wild Type ◽  
Immunoglobulin Receptor ◽  
E Coli ◽  
Data Support ◽  
Food Borne ◽  
Food Borne Illness ◽  
Adherence Mechanism

AbstractEscherichia coliO157:H7 is the most well-studied serotype of enterohemorrhagicE. coli(EHEC) class ofE. coliintestinal pathogens, and is responsible for many outbreaks of serious food-borne illness worldwide each year. Adherence mechanisms are a critical component of its pathogenesis, persistence in natural reservoirs, and environmental contamination.E. coliO157:H7 has a highly effective virulence operon, the Locus of Enterocyte Effacement (LEE), and its encoded intimate adherence mechanism is well characterized. However, factors involved in the preceding initial attachment are not well understood. In this study, we propose a mechanism of initial adherence used byE. coliO157:H7in vitro. We describe a bacterial protein not previously reported to be involved in adherence, Slp, and its interactions with the human host protein polymeric immunoglobulin receptor (pIgR). The human pIgR has previously been shown to act as an adherence receptor for some mucosal pathogens, and is highly expressed in the intestine. Following observation of significant colocalization betweenE. coliO157:H7 and pIgR location on Caco-2 cells, a co-immunoprecipitation (Co-IP) assay using a human recombinant Fc-tagged pIgR protein led to the identification of this protein. Disruption of Slp expression inE. coliO157:H7, through deletion of its encoding geneslp, produced a significant adherence deficiency to Caco-2 cells at early time points associated with initial adherence. Plasmid complementation ofslpfully restored the wild-type phenotype. Furthermore, immunofluorescence microscopy revealed evidence that this interaction is specific to the pathogenic strains ofE. colitested, and not the nonpathogenic strain E. coli K12. Additionally, deletion ofslpresulted in the absence of the corresponding protein band in further Co-IP assays, while the plasmid-encodedslpcomplementation of the deletion mutant strain restored the wild-type pattern. These data support the proposal that Slp directly contributes to initial adherence, with the pIgR protein as its proposed receptor.Author summaryEscherichia coliO157:H7 and other enterohemorrhagicE. coli(EHEC) are responsible for tens of thousands of cases of food-borne illness in the United States each year.E. coliO157:H7 has a particularly effective intimate adherence mechanism. However, the mechanisms of initial adherence, which facilitate attachment and virulence prior to the engagement of intimate adherence, are not well understood. In this study, we describe an initial adherence interaction between theE. coliO157:H7 Slp and the human polymeric immunoglobulin receptor (pIgR) expressed by the human colonic epithelial cell line Caco-2. The relationship was first demonstrated as a significant colocalization between the locations ofE. coliO157:H7 bacterial cells and pIgR protein using immunofluorescence microscopy. TheE. coliO157:H7 Slp protein was identified, and disruption of theslpgene resulted in a severe adherence deficiency to Caco-2 cells during initial adherence. This effect was reversed upon complementation of the Δslpstrain with a plasmid-encodedslpgene, and the constitutive over-expression ofslpresulted in hyper-adherence exceeding that of the wild-typeE. coliO157:H7. These data support the proposition that Slp directly contributes to initial adherence, with the pIgR protein as its proposed receptor.

scholarly journals Acid Resistance Systems Required for Survival of Escherichia coli O157:H7 in the Bovine Gastrointestinal Tract and in Apple Cider Are Different

2004 ◽  
Vol 70 (8) ◽  
pp. 4792-4799 ◽  
Author(s):  
Stuart B. Price ◽  
James C. Wright ◽  
Fred J. DeGraves ◽  
Marie-Pierre Castanie-Cornet ◽  
John W. Foster
Keyword(s):  
Escherichia Coli ◽  
Intestinal Tract ◽  
Acid Resistance ◽  
Wild Type ◽  
Infectious Dose ◽  
Apple Cider ◽  
E Coli ◽  
Food Borne ◽  
System 2 ◽  
System 1

ABSTRACT Escherichia coli O157:H7 is a highly acid-resistant food-borne pathogen that survives in the bovine and human gastrointestinal tracts and in acidic foods such as apple cider. This property is thought to contribute to the low infectious dose of the organism. Three acid resistance (AR) systems are expressed in stationary-phase cells. AR system 1 is σS dependent, while AR systems 2 and 3 are glutamate and arginine dependent, respectively. In this study, we sought to determine which AR systems are important for survival in acidic foods and which are required for survival in the bovine intestinal tract. Wild-type and mutant E. coli O157:H7 strains deficient in AR system 1, 2, or 3 were challenged with apple cider and inoculated into calves. Wild-type cells, adapted at pH 5.5 in the absence of glucose (AR system 1 induced), survived well in apple cider. Conversely, the mutant deficient in AR system 1, shown previously to survive poorly in calves, was susceptible to apple cider (pH 3.5), and this sensitivity was shown to be caused by low pH. Interestingly, the AR system 2-deficient mutant survived in apple cider at high levels, but its shedding from calves was significantly decreased compared to that of wild-type cells. AR system 3-deficient cells survived well in both apple cider and calves. Taken together, these results indicate that E. coli O157:H7 utilizes different acid resistance systems based on the type of acidic environment encountered.

scholarly journals Identification and Antibacterial Resistance of Bacteria Isolated from Poultry

2012 ◽  
Vol 61 (4) ◽  
pp. 323-326 ◽  
Author(s):  
FADI. E. EL-RAMI ◽  
FAWWAK. T. SLEIMAN ◽  
LEXANDER. M. ABDELNOOR
Keyword(s):  
Antibacterial Agents ◽  
Antibacterial Resistance ◽  
Bacterial Strains ◽  
Growth Promoters ◽  
E Coli ◽  
Food Borne Pathogens ◽  
Food Borne ◽  
Antibiotic Growth Promoters ◽  
Food Borne Infections ◽  
Potential Food

Food-borne infections are among the prominent health hazards. Antibacterial agents (ABA) are usually administered to poultry in Lebanon as antibiotic growth promoters (AGP), which might lead to the dissemination of resistant bacterial strains. The aims of this study were to isolate potential food borne pathogens from poultry and investigate an association between AGP usage and antibacterial resistance (ABR). Isolates were obtained from the culture of cloacae swabs and identified. Escherichia coli was the predominant isolate. There was a significant association between the use of tetracycline and gentamicin as AGP and the number of E. coli isolates resistant to these ABA.

scholarly journals An Escherichia coli O157-Specific Engineered Pyocin Prevents and Ameliorates Infection by E. coli O157:H7 in an Animal Model of Diarrheal Disease

2011 ◽  
Vol 55 (12) ◽  
pp. 5469-5474 ◽  
Author(s):  
Jennifer M. Ritchie ◽  
Jennifer L. Greenwich ◽  
Brigid M. Davis ◽  
Roderick T. Bronson ◽  
Dana Gebhart ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Diarrheal Disease ◽  
Intestinal Inflammation ◽  
Rabbit Model ◽  
Prophylactic Regimen ◽  
Content Type ◽  
Fecal Shedding ◽  
E Coli ◽  
Food Borne ◽  
Enteric Infections

ABSTRACTAvR2-V10.3 is an engineered R-type pyocin that specifically killsEscherichia coliO157, an enteric pathogen that is a major cause of food-borne diarrheal disease. New therapeutics to counteractE. coliO157 are needed, as currently available antibiotics can exacerbate the consequences of infection. We show here that orogastric administration of AvR2-V10.3 can prevent or ameliorateE. coliO157:H7-induced diarrhea and intestinal inflammation in an infant rabbit model of infection when the compound is administered either in a postexposure prophylactic regimen or after the onset of symptoms. Notably, administration of AvR2-V10.3 also reduces bacterial carriage and fecal shedding of this pathogen. Our findings support the further development of pathogen-specific R-type pyocins as a way to treat enteric infections.

scholarly journals ArcA Controls Metabolism, Chemotaxis, and Motility Contributing to the Pathogenicity of Avian Pathogenic Escherichia coli

2015 ◽  
Vol 83 (9) ◽  
pp. 3545-3554 ◽  
Author(s):  
Fengwei Jiang ◽  
Chunxia An ◽  
Yinli Bao ◽  
Xuefeng Zhao ◽  
Robert L. Jernigan ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Rna Seq ◽  
Global Regulator ◽  
Content Type ◽  
E Coli ◽  
Citrate Metabolism ◽  
Food Borne ◽  
Pathogenic Escherichia Coli ◽  
And Control ◽  
Potential Food

Avian pathogenicEscherichia coli(APEC) strains cause one of the three most significant infectious diseases in the poultry industry and are also potential food-borne pathogens threating human health. In this study, we showed that ArcA (aerobicrespiratorycontrol), a global regulator important forE. coli's adaptation from anaerobic to aerobic conditions and control of that bacterium's enzymatic defenses against reactive oxygen species (ROS), is involved in the virulence of APEC. Deletion ofarcAsignificantly attenuates the virulence of APEC in the duck model. Transcriptome sequencing (RNA-Seq) analyses comparing the APEC wild type and thearcAmutant indicate that ArcA regulates the expression of 129 genes, including genes involved in citrate transport and metabolism, flagellum synthesis, and chemotaxis. Further investigations revealed thatcitCEFXGcontributed to APEC's microaerobic growth at the lag and log phases when cultured in duck serum and that ArcA played a dual role in the control of citrate metabolism and transportation. In addition, deletion of flagellar genesmotAandmotBand chemotaxis genecheAsignificantly attenuated the virulence of APEC, and ArcA was shown to directly regulate the expression ofmotA,motB, andcheA. The combined results indicate that ArcA controls metabolism, chemotaxis, and motility contributing to the pathogenicity of APEC.

Expression and morphology of enterotoxigenicEscherichia colisurface antigen CS31A inE. coliK12 andVibrio cholerae

2012 ◽  
Vol 58 (6) ◽  
pp. 728-737
Author(s):  
Kathrin Kuehni-Boghenbor ◽  
Helene A. Jordi ◽  
Joachim Frey ◽  
Edy M. Vilei ◽  
Didier Favre ◽  
...  
Keyword(s):  
Diarrheal Disease ◽  
Phase Variation ◽  
Surface Expression ◽  
Coli Strain ◽  
Enterotoxigenic Escherichia Coli ◽  
Wild Type ◽  
Western Blots ◽  
E Coli ◽  
Recombinant Strains ◽  
In The Wild

Enterotoxigenic Escherichia coli (ETEC) is known as a worldwide cause of diarrheal disease. The pathogenesis involves the attachment of the microorganisms to the mucosa and the production of enterotoxins. Surface expression of CS31A fimbriae was assessed by Western blots, dot blots, immunofluorescence, and electron microscopy using negative staining and immunogold labeling. These investigations revealed significant differences in both the morphology of the wild-type and recombinant strains and the antigen exposure of CS31A in the wild-type and recombinant strains. In the wild-type ETEC strain, expression of CS31A was subject to phase variation. The recombinant E. coli strain produced CS31A but was prone to epitope shedding. In Vibrio cholerae vaccine strain CVD 103-HgR, the recombinant CS31A antigen was expressed but was only found intracellularly. Thus, E. coli strains seem to lend themselves better to the development of recombinant vaccines expressing ETEC-specific antigens at the cell’s surface than strains from other orders or genera such as V. cholerae.

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