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Alharbi MG, Al-Hindi RR, Esmael A, Alotibi IA, Azhari SA, Alseghayer MS, Teklemariam AD. The "Big Six": Hidden Emerging Foodborne Bacterial Pathogens. Trop Med Infect Dis 2022; 7:356. [PMID: 36355898 PMCID: PMC9693546 DOI: 10.3390/tropicalmed7110356] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 10/27/2022] [Accepted: 10/31/2022] [Indexed: 04/20/2024] Open
Abstract
Non-O157 Shiga toxin-producing Escherichia coli (STEC) are emerging serogroups that often result in diseases ranging from diarrhea to severe hemorrhagic colitis in humans. The most common non-O157 STEC are O26, O45, O103, O111, O121, and O145. These serogroups are known by the name "big six" because they cause severe illness and death in humans and the United States Department of Agriculture declared these serogroups as food contaminants. The lack of fast and efficient diagnostic methods exacerbates the public impact of the disease caused by these serogroups. Numerous outbreaks have been reported globally and most of these outbreaks were caused by ingestion of contaminated food or water as well as direct contact with reservoirs. Livestock harbor a variety of non-O157 STEC serovars that can contaminate meat and dairy products, or water sources when used for irrigation. Hence, effective control and prevention approaches are required to safeguard the public from infections. This review addresses the disease characteristics, reservoirs, the source of infections, the transmission of the disease, and major outbreaks associated with the six serogroups ("big six") of non-O157 STEC encountered all over the globe.
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Affiliation(s)
- Mona G. Alharbi
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Rashad R. Al-Hindi
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Ahmed Esmael
- Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, NE 68583, USA
- Botany and Microbiology Department, Faculty of Science, Benha University, Benha 13518, Egypt
| | - Ibrahim A. Alotibi
- Health Information Technology Department, Applied College, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Sheren A. Azhari
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Mazen S. Alseghayer
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
- Monitoring and Risk Assessment Department, Saudi Food and Drug Authority, Riyadh 13513, Saudi Arabia
| | - Addisu D. Teklemariam
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia
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2
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Costa M, Sucari A, Epszteyn S, Oteiza J, Gentiluomo J, Melamed C, Figueroa Y, Mingorance S, Grisaro A, Spioussas S, Almeida MB, Caruso M, Pontoni A, Signorini M, Leotta G. Comparison of six commercial systems for the detection of non-O157 STEC in meat and vegetables. Food Microbiol 2019; 84:103273. [DOI: 10.1016/j.fm.2019.103273] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 07/13/2019] [Accepted: 07/15/2019] [Indexed: 10/26/2022]
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3
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Yang X, Zhang Y. Expression of recombinant transglutaminase gene in Pichia pastoris and its uses in restructured meat products. Food Chem 2019; 291:245-252. [PMID: 31006466 DOI: 10.1016/j.foodchem.2019.04.015] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 03/22/2019] [Accepted: 04/03/2019] [Indexed: 10/27/2022]
Abstract
Transglutaminase is an effective enzyme that catalyzes the crosslinking of various meats, improves meat product quality, and is widely used in the meat industry. In this study, microbial transglutaminase (MTG) was expressed successfully in Pichia pastoris strain GS115, and the enzyme activity was approximately 0.70 U/ml. The recombinant MTG expressed in P. pastoris was used in the investigation of restructured pork and crosslinking of soy protein isolate (SPI) and chicken myofibrillar protein (MP). Results showed that the hardness, chewiness, and F1 of the restructured pork increased, and the adhesiveness decreased after MTG treatment, However, high temperature had greater effect on the texture of restructured pork after MTG treatment than that of the control. MTG can crosslink SPI component acidic subunits, subunits of β-conglycinin and MP component myosin heavy chain, and actin. MTG, as a food additive, can be successfully heterologously expressed, and the recombinant MTG has potential application in restructured meat products.
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Affiliation(s)
- Xiuqing Yang
- Institute of Biotechnology, Shanxi University, Taiyuan 030006, Shanxi, China.
| | - Yumeng Zhang
- Institute of Biotechnology, Shanxi University, Taiyuan 030006, Shanxi, China.
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Detection of Shiga Toxin-producing Escherichia coli in Ground Beef: Evaluation of Contamination Levels in Butcheries of The Metropolitan Zone in Asuncion, Paraguay. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2019. [DOI: 10.22207/jpam.13.1.08] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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5
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Chellapandi P, Prisilla A. PCR-based molecular diagnosis of botulism (types C and D) outbreaks in aquatic birds. ANN MICROBIOL 2018. [DOI: 10.1007/s13213-018-1390-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
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6
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Kiel M, Sagory-Zalkind P, Miganeh C, Stork C, Leimbach A, Sekse C, Mellmann A, Rechenmann F, Dobrindt U. Identification of Novel Biomarkers for Priority Serotypes of Shiga Toxin-Producing Escherichia coli and the Development of Multiplex PCR for Their Detection. Front Microbiol 2018; 9:1321. [PMID: 29997582 PMCID: PMC6028524 DOI: 10.3389/fmicb.2018.01321] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 05/30/2018] [Indexed: 12/22/2022] Open
Abstract
It would be desirable to have an unambiguous scheme for the typing of Shiga toxin-producing Escherichia coli (STEC) isolates to subpopulations. Such a scheme should take the high genomic plasticity of E. coli into account and utilize the stratification of STEC into subgroups, based on serotype or phylogeny. Therefore, our goal was to identify specific marker combinations for improved classification of STEC subtypes. We developed and evaluated two bioinformatic pipelines for genomic marker identification from larger sets of bacterial genome sequences. Pipeline A performed all-against-all BLASTp analyses of gene products predicted in STEC genome test sets against a set of control genomes. Pipeline B identified STEC marker genes by comparing the STEC core proteome and the "pan proteome" of a non-STEC control group. Both pipelines defined an overlapping, but not identical set of discriminative markers for different STEC subgroups. Differential marker prediction resulted from differences in genome assembly, ORF finding and inclusion cut-offs in both workflows. Based on the output of the pipelines, we defined new specific markers for STEC serogroups and phylogenetic groups frequently associated with outbreaks and cases of foodborne illnesses. These included STEC serogroups O157, O26, O45, O103, O111, O121, and O145, Shiga toxin-positive enteroaggregative E. coli O104:H4, and HUS-associated sequence type (ST)306. We evaluated these STEC marker genes for their presence in whole genome sequence data sets. Based on the identified discriminative markers, we developed a multiplex PCR (mPCR) approach for detection and typing of the targeted STEC. The specificity of the mPCR primer pairs was verified using well-defined clinical STEC isolates as well as isolates from the ECOR, DEC, and HUSEC collections. The application of the STEC mPCR for food analysis was tested with inoculated milk. In summary, we evaluated two different strategies to screen large genome sequence data sets for discriminative markers and implemented novel marker genes found in this genome-wide approach into a DNA-based typing tool for STEC that can be used for the characterization of STEC from clinical and food samples.
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Affiliation(s)
- Matthias Kiel
- Institute of Hygiene, University of Münster, Münster, Germany
| | | | - Céline Miganeh
- Genostar Bioinformatics, Montbonnot-Saint-Martin, France
| | - Christoph Stork
- Institute of Hygiene, University of Münster, Münster, Germany
| | | | | | | | | | - Ulrich Dobrindt
- Institute of Hygiene, University of Münster, Münster, Germany
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7
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Castro VS, Carvalho RCT, Conte-Junior CA, Figuiredo EES. Shiga-toxin ProducingEscherichia coli: Pathogenicity, Supershedding, Diagnostic Methods, Occurrence, and Foodborne Outbreaks. Compr Rev Food Sci Food Saf 2017; 16:1269-1280. [DOI: 10.1111/1541-4337.12302] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 08/09/2017] [Accepted: 08/11/2017] [Indexed: 12/14/2022]
Affiliation(s)
- Vinicius Silva Castro
- Animal Science Program, Faculdade de Agronomia e Zootecnia; Univ. Federal de Mato Grosso; 78060-900 Mato Grosso Brazil
- Natl. Inst. of Health Quality Control; Fundação Oswaldo Cruz; Rio de Janeiro 21040-900 Rio de Janeiro Brazil
| | - Ricardo César Tavares Carvalho
- Nutrition, Food and Metabolism Program, Faculdade de Nutrição; Univ. Federal de Mato Grosso; 78060-900 Mato Grosso Brazil
| | - Carlos Adam Conte-Junior
- Dept. of Food Technology, Faculdade de Veterinária; Univ. Federal Fluminense; 24230-340 Rio de Janeiro Brazil
- Food Science Program, Inst. de Química; Univ. Federal do Rio de Janeiro; 21941-909 Rio de Janeiro Brazil
- Natl. Inst. of Health Quality Control; Fundação Oswaldo Cruz; Rio de Janeiro 21040-900 Rio de Janeiro Brazil
| | - Eduardo Eustáquio Souza Figuiredo
- Animal Science Program, Faculdade de Agronomia e Zootecnia; Univ. Federal de Mato Grosso; 78060-900 Mato Grosso Brazil
- Nutrition, Food and Metabolism Program, Faculdade de Nutrição; Univ. Federal de Mato Grosso; 78060-900 Mato Grosso Brazil
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Mondani L, Delannoy S, Mathey R, Piat F, Mercey T, Slimani S, Fach P, Livache T, Roupioz Y. Fast detection of both O157 and non-O157 shiga-toxin producing Escherichia coli by real-time optical immunoassay. Lett Appl Microbiol 2016; 62:39-46. [PMID: 26432989 DOI: 10.1111/lam.12503] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 09/04/2015] [Accepted: 09/24/2015] [Indexed: 11/28/2022]
Abstract
UNLABELLED Among bacterial pathogens involved in food-illnesses, seven serogroups (O26, O45, O103, O111, O121, O145 and O157) of Shiga-toxin producing Escherichia coli (STEC), are frequently identified. During such outbreak, and due to the perishable property of most foodstuff, the time laps for the identification of contaminated products and pathogens is thus critical to better circumvent their spread. Traditional detection methods using PCR or culture plating are time consuming and may present some limitations. In this study, we present a multiplexed immunoassay for the optical detection of most commonly enterohemorrhagic E. coli serogroups: O26, O45, O103, O111, O121, O145 and O157:H7 in a single device. The use of Surface Plasmon Resonance imaging not only enabled the label-free analysis of the samples but gave results in a real-time manner. A dedicated protocol was set up for the detection of both low contaminating bacterial concentrations of food samples (5 CFU per 25 g) and postenrichment aliquots. By combining one single device for the detection of O157 and non-O157 STEC in a label-free manner, this rapid approach may have an important economic and societal impact. SIGNIFICANCE AND IMPACT OF THE STUDY This article presents a simple-to-operate immunoassay for the specific detection of Shiga-toxin producing Escherichia coli (STEC). This approach consists in the on-chip assay detection of viable cells on a specifically designed antibody microarray. By skipping any enrichment step and avoiding the use of labelling agent, this approach based on the Surface Plasmon Resonance imaging of the microarrays turns out to be much faster and more cost effective by comparison with standardized methods.
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Affiliation(s)
- L Mondani
- University of Grenoble Alpes, INAC-SPRAM, Grenoble, France.,CEA, INAC-SPrAM, Grenoble, France.,CNRS, INAC-SPrAM, Grenoble, France
| | - S Delannoy
- Université Paris-Est, ANSES, Food Safety Laboratory, Platform IdentyPath, Maisons-Alfort, France
| | - R Mathey
- University of Grenoble Alpes, INAC-SPRAM, Grenoble, France.,CEA, INAC-SPrAM, Grenoble, France.,CNRS, INAC-SPrAM, Grenoble, France
| | - F Piat
- Prestodiag, Villejuif, France
| | | | | | - P Fach
- Université Paris-Est, ANSES, Food Safety Laboratory, Platform IdentyPath, Maisons-Alfort, France
| | - T Livache
- University of Grenoble Alpes, INAC-SPRAM, Grenoble, France.,CEA, INAC-SPrAM, Grenoble, France.,CNRS, INAC-SPrAM, Grenoble, France
| | - Y Roupioz
- University of Grenoble Alpes, INAC-SPRAM, Grenoble, France.,CEA, INAC-SPrAM, Grenoble, France.,CNRS, INAC-SPrAM, Grenoble, France
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9
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Iguchi A, Iyoda S, Seto K, Nishii H, Ohnishi M, Mekata H, Ogura Y, Hayashi T. Six Novel O Genotypes from Shiga Toxin-Producing Escherichia coli. Front Microbiol 2016; 7:765. [PMID: 27242776 PMCID: PMC4873512 DOI: 10.3389/fmicb.2016.00765] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 05/06/2016] [Indexed: 11/13/2022] Open
Abstract
Serotyping is one of the typing techniques used to classify strains within the same species. O-serogroup diversification shows a strong association with the genetic diversity of O-antigen biosynthesis genes. In a previous study, based on the O-antigen biosynthesis gene cluster (O-AGC) sequences of 184 known Escherichia coli O serogroups (from O1 to O187), we developed a comprehensive and practical molecular O serogrouping (O genotyping) platform using a polymerase chain reaction (PCR) method, named E. coli O-genotyping PCR. Although, the validation assay using the PCR system showed that most of the tested strains were successfully classified into one of the O genotypes, it was impossible to classify 6.1% (35/575) of the strains, suggesting the presence of novel O genotypes. In this study, we conducted sequence analysis of O-AGCs from O-genotype untypeable Shiga toxin-producing E. coli (STEC) strains and identified six novel O genotypes; OgN1, OgN8, OgN9, OgN10, OgN12 and OgN31, with unique wzx and/or wzy O-antigen processing gene sequences. Additionally, to identify these novel O-genotypes, we designed specific PCR primers. A screen of O genotypes using O-genotype untypeable strains showed 13 STEC strains were classified into five novel O genotypes. The O genotyping at the molecular level of the O-AGC would aid in the characterization of E. coli isolates and will assist future studies in STEC epidemiology and phylogeny.
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Affiliation(s)
- Atsushi Iguchi
- Department of Animal and Grassland Sciences, Faculty of Agriculture, University of Miyazaki Miyazaki, Japan
| | - Sunao Iyoda
- Department of Bacteriology I, National Institute of Infectious Diseases Tokyo, Japan
| | - Kazuko Seto
- Division of Bacteriology, Osaka Prefectural Institute of Public Health Osaka, Japan
| | - Hironobu Nishii
- Department of Animal and Grassland Sciences, Faculty of Agriculture, University of Miyazaki Miyazaki, Japan
| | - Makoto Ohnishi
- Department of Bacteriology I, National Institute of Infectious Diseases Tokyo, Japan
| | - Hirohisa Mekata
- Organization for Promotion of Tenure Track, University of MiyazakiMiyazaki, Japan; Center for Animal Disease Control, University of MiyazakiMiyazaki, Japan
| | - Yoshitoshi Ogura
- Department of Bacteriology, Faculty of Medical Sciences, Kyushu University Fukuoka, Japan
| | - Tetsuya Hayashi
- Department of Bacteriology, Faculty of Medical Sciences, Kyushu University Fukuoka, Japan
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10
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Baker CA, Park SH, Kim SA, Rubinelli PM, Roto SM, Lee SI, Ramsaroop S, Miller M, Ricke SC. Formalin-fixed cells as an internal standard approach for the detection and quantitative assessment of Shiga toxin-producing Escherichia coli (STEC). Food Control 2016. [DOI: 10.1016/j.foodcont.2015.11.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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11
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Parsons BD, Zelyas N, Berenger BM, Chui L. Detection, Characterization, and Typing of Shiga Toxin-Producing Escherichia coli. Front Microbiol 2016; 7:478. [PMID: 27148176 PMCID: PMC4828450 DOI: 10.3389/fmicb.2016.00478] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Accepted: 03/22/2016] [Indexed: 02/04/2023] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) are responsible for gastrointestinal diseases reported in numerous outbreaks around the world. Given the public health importance of STEC, effective detection, characterization and typing is critical to any medical laboratory system. While non-O157 serotypes account for the majority of STEC infections, frontline microbiology laboratories may only screen for STEC using O157-specific agar-based methods. As a result, non-O157 STEC infections are significantly under-reported. This review discusses recent advances on the detection, characterization and typing of STEC with emphasis on work performed at the Alberta Provincial Laboratory for Public Health (ProvLab). Candidates for the detection of all STEC serotypes include chromogenic agars, enzyme immunoassays (EIA) and quantitative real time polymerase chain reaction (qPCR). Culture methods allow further characterization of isolates, whereas qPCR provides the greatest sensitivity and specificity, followed by EIA. The virulence gene profiles using PCR arrays and stx gene subtypes can subsequently be determined. Different non-O157 serotypes exhibit markedly different virulence gene profiles and a greater prevalence of stx1 than stx2 subtypes compared to O157:H7 isolates. Finally, recent innovations in whole genome sequencing (WGS) have allowed it to emerge as a candidate for the characterization and typing of STEC in diagnostic surveillance isolates. Methods of whole genome analysis such as single nucleotide polymorphisms and k-mer analysis are concordant with epidemiological data and standard typing methods, such as pulsed-field gel electrophoresis and multiple-locus variable number tandem repeat analysis while offering additional strain differentiation. Together these findings highlight improved strategies for STEC detection using currently available systems and the development of novel approaches for future surveillance.
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Affiliation(s)
- Brendon D. Parsons
- Laboratory Medicine and Pathology, University of AlbertaEdmonton, AB, Canada
| | - Nathan Zelyas
- Medical Microbiology and Immunology, University of AlbertaEdmonton, AB, Canada
| | - Byron M. Berenger
- Medical Microbiology and Immunology, University of AlbertaEdmonton, AB, Canada
| | - Linda Chui
- Laboratory Medicine and Pathology, University of AlbertaEdmonton, AB, Canada
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Abstract
Shiga toxin-producing Escherichia coli (STEC) strains are commonly found in the intestine of ruminant species of wild and domestic animals. Excretion of STEC with animal feces results in a broad contamination of food and the environment. Humans get infected with STEC through ingestion of contaminated food, by contact with the environment, and from STEC-excreting animals and humans. STEC strains can behave as human pathogens, and some of them, called enterohemorrhagic E. coli (EHEC), may cause hemorrhagic colitis (HC) and hemolytic-uremic syndrome (HUS). Because of the diversity of STEC types, detection strategies for STEC and EHEC are based on the identification of Shiga toxins or the underlying genes. Cultural enrichment of STEC from test samples is needed for identification, and different protocols were developed for this purpose. Multiplex real-time PCR protocols (ISO/CEN TS13136 and USDA/FSIS MLG5B.01) have been developed to specifically identify EHEC by targeting the LEE (locus of enterocyte effacement)-encoded eae gene and genes for EHEC-associated O groups. The employment of more genetic markers (nle and CRISPR) is a future challenge for better identification of EHEC from any kinds of samples. The isolation of STEC or EHEC from a sample is required for confirmation, and different cultivation protocols and media for this purpose have been developed. Most STEC strains present in food, animals, and the environment are eae negative, but some of these strains can cause HC and HUS in humans as well. Phenotypic assays and molecular tools for typing EHEC and STEC strains are used to detect and characterize human pathogenic strains among members of the STEC group.
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13
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Delannoy S, Chaves BD, Ison SA, Webb HE, Beutin L, Delaval J, Billet I, Fach P. Revisiting the STEC Testing Approach: Using espK and espV to Make Enterohemorrhagic Escherichia coli (EHEC) Detection More Reliable in Beef. Front Microbiol 2016; 7:1. [PMID: 26834723 PMCID: PMC4722105 DOI: 10.3389/fmicb.2016.00001] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Accepted: 01/05/2016] [Indexed: 11/29/2022] Open
Abstract
Current methods for screening Enterohemorrhagic Escherichia coli (EHEC) O157 and non-O157 in beef enrichments typically rely on the molecular detection of stx, eae, and serogroup-specific wzx or wzy gene fragments. As these genetic markers can also be found in some non-EHEC strains, a number of "false positive" results are obtained. Here, we explore the suitability of five novel molecular markers, espK, espV, ureD, Z2098, and CRISPRO26:H11 as candidates for a more accurate screening of EHEC strains of greater clinical significance in industrialized countries. Of the 1739 beef enrichments tested, 180 were positive for both stx and eae genes. Ninety (50%) of these tested negative for espK, espV, ureD, and Z2098, but 12 out of these negative samples were positive for the CRISPRO26:H11 gene marker specific for a newly emerging virulent EHEC O26:H11 French clone. We show that screening for stx, eae, espK, and espV, in association with the CRISPRO26:H11 marker is a better approach to narrow down the EHEC screening step in beef enrichments. The number of potentially positive samples was reduced by 48.88% by means of this alternative strategy compared to the European and American reference methods, thus substantially improving the discriminatory power of EHEC screening systems. This approach is in line with the EFSA (European Food Safety Authority) opinion on pathogenic STEC published in 2013.
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Affiliation(s)
- Sabine Delannoy
- Food Safety Laboratory, Université Paris-Est, Anses (French Agency for Food, Environmental and Occupational Health and Safety), Platform IdentyPathMaisons-Alfort, France
| | - Byron D. Chaves
- Department of Animal and Food Sciences, Texas Tech UniversityLubbock, TX, USA
| | - Sarah A. Ison
- Department of Animal and Food Sciences, Texas Tech UniversityLubbock, TX, USA
| | - Hattie E. Webb
- Department of Animal and Food Sciences, Texas Tech UniversityLubbock, TX, USA
| | - Lothar Beutin
- Division of Microbial Toxins, National Reference Laboratory for Escherichia coli, Federal Institute for Risk AssessmentBerlin, Germany
| | - José Delaval
- Laboratoire de Touraine, (LDA37) Conseil DépartementalTours, France
| | | | - Patrick Fach
- Food Safety Laboratory, Université Paris-Est, Anses (French Agency for Food, Environmental and Occupational Health and Safety), Platform IdentyPathMaisons-Alfort, France
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15
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Shridhar PB, Noll LW, Shi X, An B, Cernicchiaro N, Renter DG, Nagaraja TG, Bai J. Multiplex Quantitative PCR Assays for the Detection and Quantification of the Six Major Non-O157 Escherichia coli Serogroups in Cattle Feces. J Food Prot 2016; 79:66-74. [PMID: 26735031 DOI: 10.4315/0362-028x.jfp-15-319] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Shiga toxin-producing Escherichia coli (STEC) serogroups O26, O45, O103, O111, O121, and O145, called non-O157 STEC, are important foodborne pathogens. Cattle, a major reservoir, harbor the organisms in the hindgut and shed them in the feces. Although limited data exist on fecal shedding, concentrations of non-O157 STEC in feces have not been reported. The objectives of our study were (i) to develop and validate two multiplex quantitative PCR (mqPCR) assays, targeting O-antigen genes of O26, O103, and O111 (mqPCR-1) and O45, O121, and O145 (mqPCR-2); (ii) to utilize the two assays, together with a previously developed four-plex qPCR assay (mqPCR-3) targeting the O157 antigen and three virulence genes (stx1, stx2, and eae), to quantify seven serogroups and three virulence genes in cattle feces; and (iii) to compare the three mqPCR assays to a 10-plex conventional PCR (cPCR) targeting seven serogroups and three virulence genes and culture methods to detect seven E. coli serogroups in cattle feces. The two mqPCR assays (1 and 2) were shown to be specific to the target genes, and the detection limits were 4 and 2 log CFU/g of pure culture-spiked fecal samples, before and after enrichment, respectively. A total of 576 fecal samples collected from a feedlot were enriched in E. coli broth and were subjected to quantification (before enrichment) and detection (after enrichment). Of the 576 fecal samples subjected, before enrichment, to three mqPCR assays for quantification, 175 (30.4%) were quantifiable (≥4 log CFU/g) for at least one of the seven serogroups, with O157 being the most common serogroup. The three mqPCR assays detected higher proportions of postenriched fecal samples (P > 0.01) as positive for one or more serogroups compared with cPCR and culture methods. This is the first study to assess the applicability of qPCR assays to detect and quantify six non-O157 serogroups in cattle feces and to generate data on fecal concentration of the six serogroups.
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Affiliation(s)
- P B Shridhar
- Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas 66506, USA
| | - L W Noll
- Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas 66506, USA
| | - X Shi
- Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas 66506, USA
| | - B An
- Veterinary Diagnostic Laboratory, Kansas State University, Manhattan, Kansas 66506, USA
| | - N Cernicchiaro
- Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas 66506, USA
| | - D G Renter
- Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas 66506, USA
| | - T G Nagaraja
- Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas 66506, USA.
| | - J Bai
- Veterinary Diagnostic Laboratory, Kansas State University, Manhattan, Kansas 66506, USA.
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16
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Development of a quantitative real time PCR assay to detect and enumerate Escherichia coli O157 and O26 serogroups in bovine recto-anal swabs. J Microbiol Methods 2015; 114:9-15. [DOI: 10.1016/j.mimet.2015.04.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 04/16/2015] [Accepted: 04/16/2015] [Indexed: 01/29/2023]
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17
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Baker CA, Rubinelli PM, Park SH, Ricke SC. Immuno-based detection of Shiga toxin-producing pathogenic Escherichia coli in food – A review on current approaches and potential strategies for optimization. Crit Rev Microbiol 2015; 42:656-75. [DOI: 10.3109/1040841x.2015.1009824] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Christopher A. Baker
- Department of Food Science, Center for Food Safety, University of Arkansas, Fayetteville, AR, USA
| | - Peter M. Rubinelli
- Department of Food Science, Center for Food Safety, University of Arkansas, Fayetteville, AR, USA
| | - Si Hong Park
- Department of Food Science, Center for Food Safety, University of Arkansas, Fayetteville, AR, USA
| | - Steven C. Ricke
- Department of Food Science, Center for Food Safety, University of Arkansas, Fayetteville, AR, USA
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Beutin L, Delannoy S, Fach P. Sequence Variations in the Flagellar Antigen Genes fliCH25 and fliCH28 of Escherichia coli and Their Use in Identification and Characterization of Enterohemorrhagic E. coli (EHEC) O145:H25 and O145:H28. PLoS One 2015; 10:e0126749. [PMID: 26000885 PMCID: PMC4441469 DOI: 10.1371/journal.pone.0126749] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Accepted: 04/07/2015] [Indexed: 11/19/2022] Open
Abstract
Enterohemorrhagic E. coli (EHEC) serogroup O145 is regarded as one of the major EHEC serogroups involved in severe infections in humans. EHEC O145 encompasses motile and non-motile strains of serotypes O145:H25 and O145:H28. Sequencing the fliC-genes associated with the flagellar antigens H25 and H28 revealed the genetic diversity of the fliCH25 and fliCH28 gene sequences in E. coli. Based on allele discrimination of these fliC-genes real-time PCR tests were designed for identification of EHEC O145:H25 and O145:H28. The fliCH25 genes present in O145:H25 were found to be very similar to those present in E. coli serogroups O2, O100, O165, O172 and O177 pointing to their common evolution but were different from fliCH25 genes of a multiple number of other E. coli serotypes. In a similar way, EHEC O145:H28 harbor a characteristic fliCH28 allele which, apart from EHEC O145:H28, was only found in enteropathogenic (EPEC) O28:H28 strains that shared some common traits with EHEC O145:H28. The real time PCR-assays targeting these fliCH25[O145] and fliCH28[O145] alleles allow better characterization of EHEC O145:H25 and EHEC O145:H28. Evaluation of these PCR assays in spiked ready-to eat salad samples resulted in specific detection of both types of EHEC O145 strains even when low spiking levels of 1-10 cfu/g were used. Furthermore these PCR assays allowed identification of non-motile E. coli strains which are serologically not typable for their H-antigens. The combined use of O-antigen genotyping (O145wzy) and detection of the respective fliCH25[O145] and fliCH28[O145] allele types contributes to improve identification and molecular serotyping of E. coli O145 isolates.
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Affiliation(s)
- Lothar Beutin
- National Reference Laboratory for Escherichia coli, Federal Institute for Risk Assessment (BfR), Diedersdorfer Weg 1, D-12277, Berlin, Germany
| | - Sabine Delannoy
- Université Paris-Est, Anses (French Agency for Food, Environmental and Occupational Health and Safety), Food Safety Laboratory, IdentyPath platform, 14 rue Pierre et Marie Curie, Fr-94700, Maisons-Alfort, France
| | - Patrick Fach
- Université Paris-Est, Anses (French Agency for Food, Environmental and Occupational Health and Safety), Food Safety Laboratory, IdentyPath platform, 14 rue Pierre et Marie Curie, Fr-94700, Maisons-Alfort, France
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Salazar JK, Wang Y, Yu S, Wang H, Zhang W. Polymerase chain reaction-based serotyping of pathogenic bacteria in food. J Microbiol Methods 2015; 110:18-26. [DOI: 10.1016/j.mimet.2015.01.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 01/09/2015] [Accepted: 01/14/2015] [Indexed: 10/24/2022]
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20
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Evaluation of enzyme immunoassays and real-time PCR for detecting Shiga toxin-producing Escherichia coli in Southern Alberta, Canada. J Clin Microbiol 2015; 53:1019-23. [PMID: 25588656 DOI: 10.1128/jcm.03288-14] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Two immunoassays (Shiga Toxin Chek and Shiga Toxin Quik Chek) and real-time PCR were used to detect Shiga toxin-producing Escherichia coli. For enriched culture, the sensitivity and specificity of the three methods ranged from 80.0% to 98.2% and 98.0% to 100.0%, respectively. STEC isolates were identified in 2.6% of the 784 samples.
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21
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Draft Whole-Genome Sequences of Three Shiga Toxin-Producing Escherichia coli O91:H21 Isolates, Two from Hemolytic Uremic Syndrome Patients and One of Porcine Origin. GENOME ANNOUNCEMENTS 2014; 2:2/5/e01000-14. [PMID: 25301649 PMCID: PMC4192381 DOI: 10.1128/genomea.01000-14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This study presents three genomes of O91:H21 isolates, two from hemolytic uremic syndrome patients and one of porcine origin. Genome analyses reveal that one of the human isolates contains both Shiga toxin-encoding genes (stx1 and stx2), and all three isolates contain putative adhesin (iha and eaeH) and antibiotic resistance (ampC) genes.
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Padola NL, Etcheverría AI. Shiga toxin-producing Escherichia coli in human, cattle, and foods. Strategies for detection and control. Front Cell Infect Microbiol 2014; 4:89. [PMID: 25072032 PMCID: PMC4078642 DOI: 10.3389/fcimb.2014.00089] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Accepted: 06/12/2014] [Indexed: 01/15/2023] Open
Affiliation(s)
- Nora L Padola
- Animal Health and Preventive Medicine, Inmunochemistry and Biotechnology, CIVETAN-CONICET-CICPBA-Faculty of Veterinary Sciences- Universidad Nacional del Centro de la Provincia de Buenos Aires Tandil, Buenos Aires, Argentina
| | - Analía I Etcheverría
- Animal Health and Preventive Medicine, Inmunochemistry and Biotechnology, CIVETAN-CONICET-CICPBA-Faculty of Veterinary Sciences- Universidad Nacional del Centro de la Provincia de Buenos Aires Tandil, Buenos Aires, Argentina
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23
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Padola NL. Advances in detection methods for Shiga toxin-producing Escherichia coli (STEC). Front Microbiol 2014; 5:277. [PMID: 24926291 PMCID: PMC4046177 DOI: 10.3389/fmicb.2014.00277] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 05/21/2014] [Indexed: 11/13/2022] Open
Affiliation(s)
- Nora L Padola
- Inmunoquímica y Biotecnología-CIVETAN-CONICET-CIC-FCV-Universidad Nacional del Centro de la Provincia de Buenos Aires Tandil, Argentina
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Uhlich GA, Chen CY, Cottrell BJ, Nguyen LH. Growth media and temperature effects on biofilm formation by serotype O157:H7 and non-O157 Shiga toxin-producingEscherichia coli. FEMS Microbiol Lett 2014; 354:133-41. [DOI: 10.1111/1574-6968.12439] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Revised: 02/08/2014] [Accepted: 04/01/2014] [Indexed: 11/26/2022] Open
Affiliation(s)
- Gaylen A. Uhlich
- Molecular Characterization of Foodborne Pathogens Research Unit; Eastern Regional Research Center; Agricultural Research Service; U.S. Department of Agriculture; Wyndmoor PA USA
| | - Chin-Yi Chen
- Molecular Characterization of Foodborne Pathogens Research Unit; Eastern Regional Research Center; Agricultural Research Service; U.S. Department of Agriculture; Wyndmoor PA USA
| | - Bryan J. Cottrell
- Molecular Characterization of Foodborne Pathogens Research Unit; Eastern Regional Research Center; Agricultural Research Service; U.S. Department of Agriculture; Wyndmoor PA USA
| | - Ly-Huong Nguyen
- Molecular Characterization of Foodborne Pathogens Research Unit; Eastern Regional Research Center; Agricultural Research Service; U.S. Department of Agriculture; Wyndmoor PA USA
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Chen CY, Hofmann CS, Cottrell BJ, Strobaugh Jr TP, Paoli GC, Nguyen LH, Yan X, Uhlich GA. Phenotypic and genotypic characterization of biofilm forming capabilities in non-O157 Shiga toxin-producing Escherichia coli strains. PLoS One 2013; 8:e84863. [PMID: 24386426 PMCID: PMC3874044 DOI: 10.1371/journal.pone.0084863] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Accepted: 11/20/2013] [Indexed: 01/12/2023] Open
Abstract
The biofilm life style helps bacteria resist oxidative stress, desiccation, antibiotic treatment, and starvation. Biofilm formation involves a complex regulatory gene network controlled by various environmental signals. It was previously shown that prophage insertions in mlrA and heterogeneous mutations in rpoS constituted major obstacles limiting biofilm formation and the expression of extracellular curli fibers in strains of Escherichia coli serotype O157:H7. The purpose of this study was to test strains from other important serotypes of Shiga toxin-producing E. coli (STEC) (O26, O45, O103, O111, O113, O121, and O145) for similar regulatory restrictions. In a small but diverse collection of biofilm-forming and non-forming strains, mlrA prophage insertions were identified in only 4 of the 19 strains (serotypes O103, O113, and O145). Only the STEC O103 and O113 strains could be complemented by a trans-copy of mlrA to restore curli production and Congo red (CR) dye affinity. RpoS mutations were found in 5 strains (4 serotypes), each with low CR affinity, and the defects were moderately restored by a wild-type copy of rpoS in 2 of the 3 strains attempted. Fourteen strains in this study showed no or weak biofilm formation, of which 9 could be explained by prophage insertions or rpoS mutations. However, each of the remaining five biofilm-deficient strains, as well as the two O145 strains that could not be complemented by mlrA, showed complete or nearly complete lack of motility. This study indicates that mlrA prophage insertions and rpoS mutations do limit biofilm and curli expression in the non-serotype O157:H7 STEC but prophage insertions may not be as common as in serotype O157:H7 strains. The results also suggest that lack of motility provides a third major factor limiting biofilm formation in the non-O157:H7 STEC. Understanding biofilm regulatory mechanisms will prove beneficial in reducing pathogen survival and enhancing food safety.
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Affiliation(s)
- Chin-Yi Chen
- Molecular Characterization of Foodborne Pathogens Research Unit, Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, Wyndmoor, Pennsylvania, United States of America
- * E-mail:
| | - Christopher S. Hofmann
- Molecular Characterization of Foodborne Pathogens Research Unit, Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, Wyndmoor, Pennsylvania, United States of America
| | - Bryan J. Cottrell
- Molecular Characterization of Foodborne Pathogens Research Unit, Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, Wyndmoor, Pennsylvania, United States of America
| | - Terence P. Strobaugh Jr
- Molecular Characterization of Foodborne Pathogens Research Unit, Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, Wyndmoor, Pennsylvania, United States of America
| | - George C. Paoli
- Molecular Characterization of Foodborne Pathogens Research Unit, Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, Wyndmoor, Pennsylvania, United States of America
| | - Ly-Huong Nguyen
- Molecular Characterization of Foodborne Pathogens Research Unit, Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, Wyndmoor, Pennsylvania, United States of America
| | - Xianghe Yan
- Molecular Characterization of Foodborne Pathogens Research Unit, Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, Wyndmoor, Pennsylvania, United States of America
| | - Gaylen A. Uhlich
- Molecular Characterization of Foodborne Pathogens Research Unit, Eastern Regional Research Center, Agricultural Research Service, United States Department of Agriculture, Wyndmoor, Pennsylvania, United States of America
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Hemolytic uremic syndrome following infection with O111 Shiga toxin-producing Escherichia coli revealed through molecular diagnostics. J Clin Microbiol 2013; 52:1003-5. [PMID: 24371241 DOI: 10.1128/jcm.02855-13] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We report a case of hemolytic uremic syndrome in a 69-year-old woman due to Shiga toxin-producing Escherichia coli, possibly serotype O111, to illustrate the potentially deleterious implications of a Campylobacter enzyme immunoassay (EIA) result and the increasing importance of molecular testing when conventional methods are limited.
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Xue-Han Z, Qing Y, Ya-Dong L, Bin L, Renata I, Kong-Wang H. Development of a LAMP assay for rapid detection of different intimin variants of attaching and effacing microbial pathogens. J Med Microbiol 2013; 62:1665-1672. [PMID: 23893919 DOI: 10.1099/jmm.0.054551-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Intimin harboured by pathogenic Escherichia coli (E. coli) strains is a key virulence factor involved in host cell adherence and colonization. Twenty-seven intimin-encoding E. coli attaching and effacing (eae) gene variants have been reported according to their 3' binding domain sequences. In our study, we developed a specific and sensitive loop-mediated isothermal amplification (LAMP) assay to detect all known intimin variants. Four primers specific for six regions of eae genes were designed using online software. The eae-LAMP assay was highly specific and detected all 27 tested eae variants; no cross-reactions were observed with genes from enterotoxigenic E. coli (ETEC), E. coli BL21, Salmonella, Shigella, Listeria monocytogenes, or Streptococcus suis type 2 (SS2). With the lowest detection limit of approximately 10 copies per reaction the eae-LAMP assay was 100 times more sensitive than conventional PCR. These results, and the results of tests involving food and faecal samples artificially contaminated with E. coli O157 : H7 (eaeγ+), show that the eae-LAMP assay is a simple, rapid, sensitive and specific tool for detecting intimin variants from pathogenic strains of E. coli. The eae-LAMP assay has great potential for wider applications, not only in the laboratory but also in the field setting, as it does not require specialized equipment.
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Affiliation(s)
- Zhang Xue-Han
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences; Key Laboratory of Engineering Research of Veterinary Bio-products of Agricultural Ministry; National Center for Engineering Research of Veterinary Bio-products, Nanjing 210014, China
| | - Ye Qing
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences; Key Laboratory of Engineering Research of Veterinary Bio-products of Agricultural Ministry; National Center for Engineering Research of Veterinary Bio-products, Nanjing 210014, China
| | - Liu Ya-Dong
- Nanjing Tech-Bank Bio-industry Co. Ltd, Nanjing 210000, China
| | - Li Bin
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences; Key Laboratory of Engineering Research of Veterinary Bio-products of Agricultural Ministry; National Center for Engineering Research of Veterinary Bio-products, Nanjing 210014, China
| | - Ivanek Renata
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843, USA
| | - He Kong-Wang
- Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences; Key Laboratory of Engineering Research of Veterinary Bio-products of Agricultural Ministry; National Center for Engineering Research of Veterinary Bio-products, Nanjing 210014, China
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Wang F, Yang Q, Kase JA, Meng J, Clotilde LM, Lin A, Ge B. Current trends in detecting non-O157 Shiga toxin-producing Escherichia coli in food. Foodborne Pathog Dis 2013; 10:665-77. [PMID: 23755895 DOI: 10.1089/fpd.2012.1448] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Non-O157 Shiga toxin-producing Escherichia coli (non-O157 STEC) strains are increasingly recognized as important foodborne pathogens worldwide. Together with E. coli O157:H7, six additional STEC serogroups (O26, O45, O103, O111, O121, and O145) are now regulated as adulterants in certain raw beef products in the United States. However, effective detection and isolation of non-O157 STEC strains from food matrices remain challenging. In the past decade, great attention has been paid to developing rapid and reliable detection methods for STEC in general (targeting common virulence factors) and specific STEC serogroups in particular (targeting serogroup-specific traits). This review summarizes current trends in detecting non-O157 STEC in food, including culture, immunological, and molecular methods, as well as several novel technologies.
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Affiliation(s)
- Fei Wang
- Department of Food Science, Louisiana State University Agricultural Center , Baton Rouge, Louisiana, USA
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