Genetic and Immunological Analysis of a Novel Variant of Shiga Toxin 1 from Bovine <i>Escherichia coli</i> Strains and Development of Bead‐ELISA to Detect the Variant Toxin

Ohmura‐Hoshino, Mari; Ho, Soon-Tae; Kurazono, Hisao; Igarashi, Kazuei; Yamasaki, Shinji; Takeda, Yoshifumi

doi:10.1111/j.1348-0421.2003.tb03441.x

Cited by 13 publications

(12 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1). Two clusters corresponded to the existing subtype nomenclature for subtypes Stx1c (47,66) and Stx1d (11,44). In addition to variant Stx1c-O174-DG131-3 (47,66), variants from Ount HI-N (2), ONT HI-A (1), and ONT HI-C (1) were identified as belonging to subtype Stx1c.…”

Section: Sequence Analysismentioning

confidence: 85%

“…In addition to variant Stx1c-O174-DG131-3 (47,66), variants from Ount HI-N (2), ONT HI-A (1), and ONT HI-C (1) were identified as belonging to subtype Stx1c. Only variant Stx1d-ONT-MHI813 (11,44) was found in the subtype Stx1d cluster. Two identical amino acid sequences were found for S. dysenteriae (strain 3818T) and Shigella sonnei (strain CB7888).…”

Section: Sequence Analysismentioning

confidence: 94%

See 1 more Smart Citation

Multicenter Evaluation of a Sequence-Based Protocol for Subtyping Shiga Toxins and Standardizing Stx Nomenclature

et al. 2012

View full text Add to dashboard Cite

When Shiga toxin-producing Escherichia coli (STEC) strains emerged as agents of human disease, two types of toxin were identified: Shiga toxin type 1 (Stx1) (almost identical to Shiga toxin produced by Shigella dysenteriae type 1) and the immunologically distinct type 2 (Stx2). Subsequently, numerous STEC strains have been characterized that express toxins with variations in amino acid sequence, some of which confer unique biological properties. These variants were grouped within the Stx1 or Stx2 type and often assigned names to indicate that they were not identical in sequence or phenotype to the main Stx1 or Stx2 type. A lack of specificity or consistency in toxin nomenclature has led to much confusion in the characterization of STEC strains. Because serious outcomes of infection have been attributed to certain Stx subtypes and less so with others, we sought to better define the toxin subtypes within the main Stx1 and Stx2 types. We compared the levels of relatedness of 285 valid sequence variants of Stx1 and Stx2 and identified common sequences characteristic of each of three Stx/Stx1 and seven Stx2 subtypes. A novel, simple PCR subtyping method was developed, independently tested on a battery of 48 prototypic STEC strains, and improved at six clinical and research centers to test the reproducibility, sensitivity, and specificity of the PCR. Using a consistent schema for nomenclature of the Stx toxins and stx genes by phylogenetic sequence-based relatedness of the holotoxin proteins, we developed a typing approach that should obviate the need to bioassay each newly described toxin and that predicts important biological characteristics.

show abstract

Section: Sequence Analysismentioning

confidence: 85%

Section: Sequence Analysismentioning

confidence: 94%

Multicenter Evaluation of a Sequence-Based Protocol for Subtyping Shiga Toxins and Standardizing Stx Nomenclature

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Analysis of the sequence data of the stx1d ‐positive strains (IF Ec AB8SF, IF Ec AB8Hp, IF Ec LR2) showed that they are identical (100% nucleotide homology) among each other and show 99% nucleotide homology with stx1d (strain MHI 813; Bürk et al. 2003), stx1v52 and stx1v51 genes (strains 92–1251 and 92–1252; Ohmura‐Hoshino et al. 2003).…”

Section: Resultsmentioning

confidence: 99%

First isolation of Shiga toxin 1d producing Escherichia coli variant strains in shellfish from coastal areas in France

et al. 2006

View full text Add to dashboard Cite

Aims: This study was carried out to evaluate the presence of Shiga toxin‐producing Escherichia coli (STEC) and E. coli O157:H7 in shellfish from French coastal environments. Methods and Results: Shellfish were collected in six growing areas or natural beds (B category) and nonfarming areas (D category) from July 2002 to August 2004. PCR detection of stx genes was performed on homogenized whole shellfish and digestive gland tissues enrichments. STEC strains were detected by colony DNA hybridization using a stx‐specific gene probe and E. coli O157 strains were additionally searched by immunomagnetic separation with O157‐specific magnetic beads. Stx genes were detected in 40 of 144 (27·8%) sample enrichments from mussels, oysters or cockles, 32 of 130 enrichments (24·6%) were from B‐category areas and eight of 14 (57·1%) from the D‐category area. Five strains carrying stx1 or stx1d genes and one stx negative, eae and ehxA positive E. coli O157:H7 were isolated from six of 40 stx‐positive enrichments. No relation was found between the total E. coli counts in shellfish and the presence of STEC strains in the samples. Conclusions: The STEC strains of different serotypes and stx types are present in shellfish from French coastal environments. It is the first isolation of STEC stx1d strains in France. Significance and Impact of the Study: Shellfish collected in coastal environments can serve as a vehicle for STEC transmission.

show abstract

“…Only two variants of Stx1a have been identified: Stx1c and Stx1d. Both Stx1c and Stx1d can be distinguished immunologically from Stx1 (13, 14). Stx1c and Stx1d are rarely found in human disease, and when associated with STEC isolated from patients, are linked with a mild disease course (15, 16).…”

Section: Typing and Nomenclaturementioning

confidence: 99%

Shiga Toxin (Stx) Classification, Structure, and Function

2014

View full text Add to dashboard Cite

Shiga toxin (Stx) is one of the most potent bacterial toxins known. Stx is found in Shigella dysenteriae 1 and in some serogroups of Escherichia coli (called Stx1 in E. coli). In addition to or instead of Stx1, some E. coli strains produce a second type of Stx, Stx2, that has the same mode of action as Stx/Stx1 but that is antigenically distinct. Because subtypes of each toxin have been identified, the prototype toxin for each group is now designated Stx1a or Stx2a. The Stxs consist of two major subunits, an A subunit that joins noncovalently to a pentamer of five identical B subunits. The A subunit of the toxin injures the eukaryotic ribosome, and halts protein synthesis in target cells. The function of the B pentamer is to bind to the cellular receptor, globotriaosylceramide, Gb3, found primarily on endothelial cells. The Stxs traffic in a retrograde manner within the cell, such that the A subunit of the toxin reaches the cytosol only after the toxin moves from the endosome to the Golgi and then to the endoplasmic reticulum. In humans infected with Stx-producing E. coli (STEC), the most serious manifestation of the disease, the hemolytic uremic syndrome or HUS, is more often associated with strains that produce Stx2a rather than Stx1a, and that relative toxicity is replicated in mice and baboons. Stx1a and Stx2a also exhibit differences in cytotoxicity to various cell types, bind dissimilarly to receptor analogs or mimics, induce differential chemokine responses, and have several distinctive structural characteristics.

show abstract

Genetic and Immunological Analysis of a Novel Variant of Shiga Toxin 1 from Bovine Escherichia coli Strains and Development of Bead‐ELISA to Detect the Variant Toxin

Cited by 13 publications

References 41 publications

Multicenter Evaluation of a Sequence-Based Protocol for Subtyping Shiga Toxins and Standardizing Stx Nomenclature

Multicenter Evaluation of a Sequence-Based Protocol for Subtyping Shiga Toxins and Standardizing Stx Nomenclature

First isolation of Shiga toxin 1d producing Escherichia coli variant strains in shellfish from coastal areas in France

Shiga Toxin (Stx) Classification, Structure, and Function

Contact Info

Product

Resources

About