Comparison of colony and stool blots for detection of enteropathogens by DNA probes

DNA probes that identify genes coding for heat-labile type I (LT-I) and heat-stable type 1 (ST-I) enterotoxins, enteropathogenic Escherichia coli adherence factor (EAF), and Shigella-like, invasiveness (INV) are used to evaluate the sensitivity and specificity of stool blots in comparison with the sensitivity and specificity of colony blots in detecting enteropathoghens. The sensitivities of the probes in stool blots are 91.7% for the LT-I probe, 76.9% for the ST-I probes, 78.9% for the EAF probe, and 45.5% for the INV probe. The specificity of all probes is higher than 95%. In general, the stool blot method identifies as many if not more LT-I-, ST-I-, and EAF-producing E. coli infections than the colony blots. Key words: DNA probes, stool blots, enteropathogens, diagnosis.

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Patterns of Variations in Escherichia coli Strains That Produce Cytolethal Distending Toxin

Infection and Immunity ◽

10.1128/iai.72.2.684-690.2004 ◽

2004 ◽

Vol 72 (2) ◽

pp. 684-690 ◽

Cited By ~ 21

Author(s):

Carol L. Pickett ◽

Robert B. Lee ◽

Aysegul Eyigor ◽

Ben Elitzur ◽

Emily M. Fox ◽

...

Keyword(s):

Escherichia Coli ◽

Virulence Genes ◽

Pcr Primers ◽

Pcr Analysis ◽

Cytolethal Distending Toxin ◽

E Coli ◽

Heat Stable ◽

Genes Encoding ◽

Factor Type

ABSTRACT A collection of 20 Escherichia coli strains that produce cytolethal distending toxin (CDT) were analyzed for their virulence-associated genes. All of these strains were serotyped, and multiplex PCR analysis was used to ascertain the presence of genes encoding other virulence factors, including Shiga toxin, intimin, enterohemolysin, cytotoxic necrotizing factor type 1 (CNF1) and CNF2, heat-stable toxin, and heat-labile toxin. These CDT-producing strains possessed various combinations of known virulence genes, some of which have not been noted before. Partial cdtB sequences were obtained from 10 of these strains, and their predicted CdtB sequences were compared to known E. coli CdtB sequences; some of the sequences were identical to known CdtB sequences, but two were not. PCR primers based on sequence differences between the known cdt sequences were tested for their ability to detect CDT producers and to determine CDT type. Correlations between the type of CDT produced, the presence of other virulence properties, and overall strain relatedness revealed that the CDT producers studied here can be divided into three general groups, with distinct differences in CDT type and in their complement of virulence-associated genes.

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Detection of eae, bfpA, espA Genes on Diarrhoeagenic Strains of Escherichia coli Isolates

Indonesian Journal of Biotechnology ◽

10.22146/ijbiotech.7563 ◽

2015 ◽

Vol 11 (1) ◽

Author(s):

Agnes Sri Harti ◽

Susi Iravati ◽

Widya Asmara

Keyword(s):

Public Health ◽

Escherichia Coli ◽

Protein A ◽

Dna Probes ◽

Hybridization Technique ◽

Secreted Protein ◽

Enteropathogenic Escherichia Coli ◽

E Coli ◽

Typical Epec ◽

Dna Fragment

The Enteropathogenic Escherichia coli (EPEC) is one of pathogenic strain of diarrheagenic E. coli group in children andinfant that occurs in developing countries. The significant virulence factors in pathogenic EPEC are eaeA (E. coli attachingeffacing), bfpA (bundle-forming pilus A) and espA (encoding secreted protein A) genes. The use of DNA probes to detect thevirulence genes in E. coli in Indonesia is not common yet. In this experiment the gene fragments of eae, bfpA, and espA were usedas probes to detect the EPEC among E. coli isolates from stool specimensin of diarrheic children attending Public Health Centersin Yogyakarta. The DNA samples were isolated from 49 diarrheagenic E. coli isolates. The DNA probes of eae, bfpA and espAwere obtained by amplification of DNA fragment of EPEC O126 using PCR technique. Furthermore, those probes were used toidentify the presence of those genes among E. coli isolates using hybridization technique. The results showed that 42 (85.7%)isolates were espA+, 25 isolates (51%) were eaeA+ (EPEC strains). Therefore among 25 isolates of EPEC, 20 isolates (80 %)among EPEC were bfpA+ (typical EPEC strains).Keywords : DNA probe, eae, bfpA, espA, EPEC.

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Spheroplasts of enteropathogenic Escherichia coli. I. Biological characteristics

Canadian Journal of Microbiology ◽

10.1139/m68-112 ◽

1968 ◽

Vol 14 (6) ◽

pp. 675-678 ◽

Cited By ~ 3

Author(s):

B. Diena ◽

R. Wallace ◽

L. Greenberg

Keyword(s):

Escherichia Coli ◽

Tissue Culture ◽

Biological Characteristics ◽

Enteropathogenic Escherichia Coli ◽

E Coli ◽

O Antigen ◽

Pathogenic Serotypes

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

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Biochemical and structural characterization of the novel sialic acid-binding site of Escherichia coli heat-labile enterotoxin LT-IIb

Biochemical Journal ◽

10.1042/bcj20160575 ◽

2016 ◽

Vol 473 (21) ◽

pp. 3923-3936 ◽

Cited By ~ 3

Author(s):

Dani Zalem ◽

João P. Ribeiro ◽

Annabelle Varrot ◽

Michael Lebens ◽

Anne Imberty ◽

...

Keyword(s):

Escherichia Coli ◽

Binding Site ◽

Cholera Toxin ◽

Carbohydrate Binding ◽

Type I ◽

Type Ii ◽

E Coli ◽

B Subunit ◽

Heat Labile ◽

B Subunits

The structurally related AB5-type heat-labile enterotoxins of Escherichia coli and Vibrio cholerae are classified into two major types. The type I group includes cholera toxin (CT) and E. coli LT-I, whereas the type II subfamily comprises LT-IIa, LT-IIb and LT-IIc. The carbohydrate-binding specificities of LT-IIa, LT-IIb and LT-IIc are distinctive from those of cholera toxin and E. coli LT-I. Whereas CT and LT-I bind primarily to the GM1 ganglioside, LT-IIa binds to gangliosides GD1a, GD1b and GM1, LT-IIb binds to the GD1a and GT1b gangliosides, and LT-IIc binds to GM1, GM2, GM3 and GD1a. These previous studies of the binding properties of type II B-subunits have been focused on ganglio core chain gangliosides. To further define the carbohydrate binding specificity of LT-IIb B-subunits, we have investigated its binding to a collection of gangliosides and non-acid glycosphingolipids with different core chains. A high-affinity binding of LT-IIb B-subunits to gangliosides with a neolacto core chain, such as Neu5Gcα3- and Neu5Acα3-neolactohexaosylceramide, and Neu5Gcα3- and Neu5Acα3-neolactooctaosylceramide was detected. An LT-IIb-binding ganglioside was isolated from human small intestine and characterized as Neu5Acα3-neolactohexaosylceramide. The crystal structure of the B-subunit of LT-IIb with the pentasaccharide moiety of Neu5Acα3-neolactotetraosylceramide (Neu5Ac-nLT: Neu5Acα3Galβ4GlcNAcβ3Galβ4Glc) was determined providing the first information for a sialic-binding site in this subfamily, with clear differences from that of CT and LT-I.

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Role of the ceramide-signaling pathway in cytokine responses to P-fimbriated Escherichia coli.

Journal of Experimental Medicine ◽

10.1084/jem.183.3.1037 ◽

1996 ◽

Vol 183 (3) ◽

pp. 1037-1044 ◽

Cited By ~ 115

Author(s):

M Hedlund ◽

M Svensson ◽

A Nilsson ◽

R D Duan ◽

C Svanborg

Keyword(s):

Escherichia Coli ◽

Signaling Pathway ◽

Kinase Inhibitors ◽

Human Kidney ◽

Cytokine Response ◽

Protein Kinase Inhibitors ◽

E Coli ◽

Type 1 Fimbriae ◽

Outer Leaflet

Escherichia coli express fimbriae-associated adhesins through which they attach to mucosal cells and activate a cytokine response. The receptors for E. coli P fimbriae are the globoseries of glycosphingolipids; Gal alpha 1-->4Gal beta-containing oligosaccharides bound to ceramide in the outer leaflet of the lipid bilayer. The receptors for type 1 fimbriae are mannosylated glycoproteins rather than glycolipids. This study tested the hypothesis that P-fimbriated E. coli elicit a cytokine response through the release of ceramide in the receptor-bearing cell. We used the A498 human kidney cell line, which expressed functional receptors for P and type 1 fimbriae and secreted higher levels of interleukin (IL)-6 when exposed to the fimbriated strains than to isogenic nonfimbriated controls. P-fimbriated E. coli caused the release of ceramide and increased the phosphorylation of ceramide to ceramide 1-phosphate. The IL-6 response to P-fimbriated E. coli was reduced by inhibitors of serine/threonine kinases but not by other protein kinase inhibitors. In contrast, ceramide levels were not influenced by type 1-fimbriated E. coli, and the IL-6 response was insensitive to the serine/threonine kinase inhibitors. These results demonstrate that the ceramide-signaling pathway is activated by P-fimbriated E. coli, and that the receptor specificity of the P fimbriae influences this process. We propose that this activation pathway contributes to the cytokine induction by P-fimbriated E. coli in epithelial cells.

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Novel Hybrid of Typical Enteropathogenic Escherichia coli and Shiga-Toxin-Producing E. coli (tEPEC/STEC) Emerging From Pet Birds

Frontiers in Microbiology ◽

10.3389/fmicb.2018.02975 ◽

2018 ◽

Vol 9 ◽

Cited By ~ 9

Author(s):

Rosely Martins Gioia-Di Chiacchio ◽

Marcos Paulo Vieira Cunha ◽

Lilian Rose Marques de Sá ◽

Yamê Minieiro Davies ◽

Camila Bueno Pacheco Pereira ◽

...

Keyword(s):

Escherichia Coli ◽

Shiga Toxin ◽

Enteropathogenic Escherichia Coli ◽

E Coli ◽

Pet Birds

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A New Clone Sweeps Clean: the Enigmatic Emergence of Escherichia coli Sequence Type 131

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02824-14 ◽

2014 ◽

Vol 58 (9) ◽

pp. 4997-5004 ◽

Cited By ~ 136

Author(s):

Ritu Banerjee ◽

James R. Johnson

Keyword(s):

Escherichia Coli ◽

Sequence Type ◽

Rapid Expansion ◽

Future Research ◽

Content Type ◽

Extended Spectrum Beta Lactamase ◽

E Coli ◽

Phylogenetic Studies ◽

Ecological Success

ABSTRACTEscherichia colisequence type 131 (ST131) is an extensively antimicrobial-resistantE. coliclonal group that has spread explosively throughout the world. Recent molecular epidemiologic and whole-genome phylogenetic studies have elucidated the fine clonal structure of ST131, which comprises multiple ST131 subclones with distinctive resistance profiles, including the (nested) H30, H30-R, and H30-Rx subclones. The most prevalent ST131 subclone, H30, arose from a single common fluoroquinolone (FQ)-susceptible ancestor containing allele 30 offimH(type 1 fimbrial adhesin gene). An early H30 subclone member acquired FQ resistance and launched the rapid expansion of the resulting FQ-resistant subclone, H30-R. Subsequently, a member of H30-R acquired the CTX-M-15 extended-spectrum beta-lactamase and launched the rapid expansion of the CTX-M-15-containing subclone within H30-R, H30-Rx. Clonal expansion clearly is now the dominant mechanism for the rising prevalence of both FQ resistance and CTX-M-15 production in ST131 and inE. coligenerally. Reasons for the successful dissemination and expansion of the key ST131 subclones remain undefined but may include increased transmissibility, greater ability to colonize and/or persist in the intestine or urinary tract, enhanced virulence, and more-extensive antimicrobial resistance compared to otherE. coli. Here we discuss the epidemiology and molecular phylogeny of ST131 and its key subclones, possible mechanisms for their ecological success, implications of their widespread dissemination, and future research needs.

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P fimbriae and other adhesins enhance intestinal persistence of Escherichia coli in early infancy

Epidemiology and Infection ◽

10.1017/s0950268898001137 ◽

1998 ◽

Vol 121 (3) ◽

pp. 599-608 ◽

Cited By ~ 15

Author(s):

I. ADLERBERTH ◽

C. SVANBORG ◽

B. CARLSSON ◽

L. MELLANDER ◽

L.-Å. HANSON ◽

...

Keyword(s):

Escherichia Coli ◽

Cell Line ◽

Intestinal Epithelial Cells ◽

Antigen Expression ◽

Intestinal Epithelial ◽

E Coli ◽

O Antigen ◽

Ht 29 ◽

Intestinal Persistence

Resident and transient Escherichia coli strains were identified in the rectal flora of 22 Pakistani infants followed from birth to 6 months of age. All strains were tested for O-antigen expression, adhesin specificity (P fimbriae, other mannose-resistant adhesins or type 1 fimbriae) and adherence to the colonic cell line HT-29. Resident strains displayed higher mannose- resistant adherence to HT-29 cells, and expressed P fimbriae (P=0·0036) as well as other mannose-resistant adhesins (P=0·012) more often than transient strains. In strains acquired during the first month of life, P fimbriae were 12 times more frequent in resident than in transient strains (P=0·0006). The O-antigen distribution did not differ between resident and transient strains, and none of the resident P-fimbriated strains belonged to previously recognized uropathogenic clones. The results suggest that adhesins mediating adherence to intestinal epithelial cells, especially P fimbriae, enhance the persistence of E. coli in the large intestine of infants.

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