Spheroplasts of enteropathogenic Escherichia coli. I. Biological characteristics

1968 ◽  
Vol 14 (6) ◽  
pp. 675-678 ◽  
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.

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

1991 ◽  
Vol 37 (5) ◽  
pp. 407-410
Author(s):  
Mônica A. M. Vieira ◽  
Beatriz E. C. Guth ◽  
Tânia A. T. Gomes
Keyword(s):  
Escherichia Coli ◽  
Key Words ◽  
Sensitivity And Specificity ◽  
Dna Probes ◽  
Type I ◽  
Enteropathogenic Escherichia Coli ◽  
Key Words Dna ◽  
E Coli ◽  
Heat Stable

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.

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

2018 ◽  
Vol 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

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

1998 ◽  
Vol 121 (3) ◽  
pp. 599-608 ◽  
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.

scholarly journals The population genomics of increased virulence and antibiotic resistance in human commensal Escherichia coli over 30 years in France

2021 ◽  
Author(s):  
Julie Marin ◽  
Olivier Clermont ◽  
Guilhem Royer ◽  
Melanie Mercier-Darty ◽  
Jean-Winoc Decousser ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
High Risk ◽  
Virulence Genes ◽  
Population Genomics ◽  
E Coli ◽  
O Antigen ◽  
Similar Region ◽  
Intestinal Infections ◽  
Evolution Of Virulence

Escherichia coli is a commensal species of the lower intestine, but also a major pathogen causing intestinal and extra-intestinal infections. Most studies on genomic evolution of E. coli used isolates from infections, and/or focused on antibiotic resistance, but neglected the evolution of virulence. Here instead, we whole-genome sequenced a collection of 436 E. coli isolated from fecal samples of healthy adult volunteers in France between 1980 and 2010. These isolates were distributed among 159 sequence types (STs), the five most frequent being ST10 (15.6%), ST73 (5.5%) and ST95 (4.8%), ST69 (3.7%) and ST59 (3.7%), and 230 O:H serotypes. ST and serotype diversity increased over time. Comparison with 912 E. coli bacteremia isolates from similar region and time showed a greater diversity in commensal isolates. The O1, O2, O6 and O25-groups used in bioconjugate O-antigen vaccine were found in only 63% of the four main STs associated with a high risk of bacteremia (ST69, ST73, ST95 and ST131). In commensals, STs associated with a high risk of bacteremia increased in frequency. Both extra-intestinal virulence-associated genes and resistance to antibiotics increased in frequency. Evolution of virulence genes was driven by both clonal expansion of STs with more virulence genes, and increases in frequency within STs, whereas the evolution of resistance was dominated by increases in frequency within STs. This study provides a unique picture of the phylogenomic evolution of E. coli in its human commensal habitat over a 30-year period and suggests that the efficacy of O-antigen vaccines would be threatened by serotype replacement.

scholarly journals Enteroaggregative Escherichia coli: epidemiology, virulence and detection

2007 ◽  
Vol 56 (1) ◽  
pp. 4-8 ◽  
Author(s):  
Andrej Weintraub
Keyword(s):  
Escherichia Coli ◽  
Tissue Culture ◽  
Watery Diarrhoea ◽  
Biological Assays ◽  
E Coli ◽  
The Past ◽  
Sporadic Cases ◽  
Trained Staff ◽  
Definition Of ◽  
Specific Virulence

Enteroaggregative Escherichia coli (EAEC) is a subgroup of diarrhoeagenic E. coli (DEC) that during the past decade has received increasing attention as a cause of watery diarrhoea, which is often persistent. EAEC have been isolated from children and adults worldwide. As well as sporadic cases, outbreaks of EAEC-caused diarrhoea have been described. The definition of EAEC is the ability of the micro-organism to adhere to epithelial cells such as HEp-2 in a very characteristic ‘stacked-brick’ pattern. Although many studies searching for specific virulence factor(s) unique for this category of DEC have been published it is still unknown why the EAEC cause persistent diarrhoea. In addition, the aggregative property of EAEC causes a lot of problems in serotyping due to the cells auto-agglutinating. The gold standard for identification of EAEC includes isolation of the agent and an adherence assay using tissue culture, viz. HEp-2 cells. This assay is in most cases reliable; however, emergence of ‘atypical’ EAEC has been described in several publications. In addition, the HEp-2 assay is time consuming, demands a tissue culture lab and trained staff. Several molecular biological assays have been described, however, none show 100 % specificity.

Diarrhea Associated With Adherent Enteropathogenic Escherichia coli in an Infant and Toddler Center, Seattle, Washington

PEDIATRICS ◽  
1986 ◽  
Vol 77 (3) ◽  
pp. 296-300
Author(s):  
Leonard J. Paulozzi ◽  
Kathleen E. Johnson ◽  
Lawrence M. Kamahele ◽  
Carla R. Clausen ◽  
Lee W. Riley ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Day Care ◽  
Care Center ◽  
The United States ◽  
Enteropathogenic Escherichia Coli ◽  
Day Care Center ◽  
E Coli ◽  
Published Report ◽  
The Common ◽  
Stool Cultures

During November 1983, the Seattle-King County Department of Public Health investigated an outbreak of diarrhea associated with enteropathogenic Escherichia coli, serogroup 0111:K58, in an infant and toddler day-care center. Of the 25 children in the center, ranging in age from 4 to 30 months (median age 11 months), diarrhea occurred in 14 characterized by watery, greenish stools. The median duration of diarrhea was 12 days. Two of the ill children were hospitalized because of severe dehydration. Stool cultures from the children diagnosed initially did not yield the common bacterial pathogens, parasites, or rotavirus. Stool cultures from 11 of 14 ill children and two of 11 well children (P <.005), however, yielded an E coli serogroup, 0111: K58, which was not invasive or toxigenic by standard tests. The source of the organism was not identified. Although this organism has been recognized as a cause of diarrhea in newborn nurseries, this is the first published report of a documented outbreak of enteropathogenic E coli-induced diarrhea in a day-care center in the United States.

Methodology for Enteropathogenic Escherichia coli

1975 ◽  
Vol 58 (2) ◽  
pp. 283-292
Author(s):  
Ira J Mehlman ◽  
Nicholas T Simon ◽  
Arvey C Sanders ◽  
Morris Fishbein ◽  
Joseph C Olson ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Elevated Temperature ◽  
Growth Temperature ◽  
Maximal Growth ◽  
Enteropathogenic Escherichia Coli ◽  
Pathogenic Potential ◽  
Gram Negative ◽  
Tentative Identification ◽  
E Coli ◽  
Capsular Antigens

Abstract Pathogenic biotypes of Escherichia coli grow poorly at temperatures greatly different from that of the host. Percentages quantitatively recovered at 42.0, 44.0, 44.5, and 45.5°C in lauryl tryptose broth were 100, 76, 76, and 42, respectively. Corresponding values for 175 strains of varied origin were 98, 89, 82, and 65%. Maximal growth temperature is dependent upon medium. Lauryl tryptose and elevated coliform broths were equivalent in the recovery of small inocula (100 cells/ml) at 41.5–44.5°. Mac-Conkey, enteric enrichment, and Gram-negative broths were inhibitory at corresponding values. Growth at elevated temperature in nutrient broth is enhanced by carbohydrate. Standard lactose enrichment media fail to recover slow lactose fermenters. An acidified glutamic acid medium was unsuitable for recovery of E. coli. The data suggest modification of standard temperatures for the recovery of pathogenic biotypes. Previously recommended analytical methods have been simplified and supplemented. The enhancement of motility in indole-nitrite broth at 35°C is recommended. A 4-tube semiquantitative test is offered for tentative identification of somatic and capsular antigens. Inclusion of Alkalescens-Dispar strains is warranted by their pathogenic behavior. Examination in Shigella and Alkalescens-Dispar sera is required to cover the dysentery-like biotypes. Pathogenic potential cannot be inferred from serotype.

scholarly journals Moringa oleifera Seeds Extract Activity on Enteropathogenic Escherichia coli and Aeromonas hydrophyla Cells in Aquatic Microcosm

2019 ◽  
Vol 7 (2) ◽  
pp. 13 ◽  
Author(s):  
Claire Stephane Metsopkeng ◽  
Chretien Lontsi Djimeli ◽  
Olive Vivien Noah Ewoti ◽  
Lucienne Marlyse Moungang ◽  
Paul Alain Nana ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Moringa Oleifera ◽  
Potable Water ◽  
Incubation Temperature ◽  
Enteropathogenic Escherichia Coli ◽  
Incubation Condition ◽  
E Coli ◽  
Extract Concentration ◽  
Cell Incubation ◽  
Potential Exploitation

This study aimed to evaluate in microcosm condition, the survival of Aeromonas hydrophila and Enteropathogenic Escherichia coli (EPEC), in the presence of M. oleifera aqueous seeds extract at concentrations varying from 1 to 40 g/L, and under 4 °C and 23 °C incubation temperature. It has been noted that cell abundances decrease gradually with the increasing in the seeds extract concentration. However, a marked cells regrowth was sometimes noted. In monospecies cell incubation condition, under 4 °C, the EPEC cells inhibition percentages (CIP) values varied from 52.12 to 99.84%. Those of A. hydrophila varied from 13.2 to 96%. The lowest CIPs were noted at the extract concentration 1g/L for EPEC and A. hydrophila. The highest CIP value was registered at 10 and 40 g/L for EPEC and at 15 g/L for A. hydrophila. Under 23 °C incubation, the EPEC CIPs values varied from 74.04 to 99.9% and those of A. hydrophila varied from 21.2 to 97.8%. For E. coli, the lowest and the highest CIP were recorded at the extract concentration 1g/L and 30 g/L, respectively. In bispecies cells incubation condition, the CIPs were relatively different. These results show the potential exploitation of M. oleifera extracts in the microbiological treatment of potable water.

scholarly journals Structure and genetics of Escherichia coli O antigens

2019 ◽  
Vol 44 (6) ◽  
pp. 655-683 ◽  
Author(s):  
Bin Liu ◽  
Axel Furevi ◽  
Andrei V Perepelov ◽  
Xi Guo ◽  
Hengchun Cao ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Genetic Basis ◽  
Structural Diversity ◽  
Gene Clusters ◽  
Current Standard ◽  
E Coli ◽  
Antigen Gene ◽  
O Antigen ◽  
Or Groups ◽  
O Antigens

ABSTRACT Escherichia coli includes clonal groups of both commensal and pathogenic strains, with some of the latter causing serious infectious diseases. O antigen variation is current standard in defining strains for taxonomy and epidemiology, providing the basis for many serotyping schemes for Gram-negative bacteria. This review covers the diversity in E. coli O antigen structures and gene clusters, and the genetic basis for the structural diversity. Of the 187 formally defined O antigens, six (O31, O47, O67, O72, O94 and O122) have since been removed and three (O34, O89 and O144) strains do not produce any O antigen. Therefore, structures are presented for 176 of the 181 E. coli O antigens, some of which include subgroups. Most (93%) of these O antigens are synthesized via the Wzx/Wzy pathway, 11 via the ABC transporter pathway, with O20, O57 and O60 still uncharacterized due to failure to find their O antigen gene clusters. Biosynthetic pathways are given for 38 of the 49 sugars found in E. coli O antigens, and several pairs or groups of the E. coli antigens that have related structures show close relationships of the O antigen gene clusters within clades, thereby highlighting the genetic basis of the evolution of diversity.

scholarly journals Additional Og-Typing PCR Techniques Targeting Escherichia coli-Novel and Shigella-Unique O-Antigen Biosynthesis Gene Clusters

2020 ◽  
Vol 58 (11) ◽  
Author(s):  
Atsushi Iguchi ◽  
Hironobu Nishii ◽  
Kazuko Seto ◽  
Jiro Mitobe ◽  
Kenichi Lee ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Strong Association ◽  
Gene Clusters ◽  
Epidemiological Studies ◽  
Content Type ◽  
E Coli ◽  
O Antigen ◽  
Wide Range ◽  
Biosynthesis Gene ◽  
Almost All

ABSTRACT The O-serogrouping of pathogenic Escherichia coli is a standard method for subtyping strains for epidemiological studies and controls. O-serogroup diversification shows a strong association with the genetic diversity in some O-antigen biosynthesis gene clusters. Through genomic studies, in addition to the types of O-antigen biosynthesis gene clusters (Og-types) from conventional O-serogroup strains, a number of novel Og-types have been found in E. coli isolates. To assist outbreak investigations and surveillance of pathogenic E. coli at inspection institutes, in previous studies, we developed PCR methods that could determine almost all conventional O-serogroups and some novel Og-types. However, there are still many Og-types that may not be determined by simple genetic methods such as PCR. Thus, in the present study, we aimed to develop an additional Og-typing PCR system. Based on the novel Og-types, including OgN32, OgN33, and OgN34, presented in this study, we designed an additional 24 PCR primer pairs targeting 14 novel and 2 diversified E. coli Og-types and 8 Shigella-unique Og-types. Subsequently, we developed 5 new multiplex PCR sets consisting of 33 primers, including the aforementioned 24 primers and 9 primers reported in previous studies. The accuracy and specificity of the PCR system was validated using approximately 260 E. coli and Shigella O-serogroup and Og-type reference strains. The Og-typing PCR system reported here can determine a wide range of Og-types of E. coli and may help epidemiological studies, in addition to the surveillance of pathogenic E. coli.

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