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Withenshaw SM, Smith RP, Davies R, Smith AEO, Gray E, Rodgers J. A systematized review and qualitative synthesis of potential risk factors associated with the occurrence of non‐O157 Shiga toxin‐producing
Escherichia coli
(STEC) in the primary production of cattle. Compr Rev Food Sci Food Saf 2022; 21:2363-2390. [DOI: 10.1111/1541-4337.12929] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 01/19/2022] [Accepted: 01/24/2022] [Indexed: 12/22/2022]
Affiliation(s)
- Susan M. Withenshaw
- Department of Epidemiological Sciences Animal and Plant Health Agency – Weybridge New Haw UK
| | - Richard P. Smith
- Department of Epidemiological Sciences Animal and Plant Health Agency – Weybridge New Haw UK
| | - Rob Davies
- Department of Bacteriology Animal and Plant Health Agency – Weybridge New Haw UK
| | - Alice E. O. Smith
- Department of Epidemiological Sciences Animal and Plant Health Agency – Weybridge New Haw UK
| | - Elizabeth Gray
- Department of Epidemiological Sciences Animal and Plant Health Agency – Weybridge New Haw UK
| | - John Rodgers
- Department of Bacteriology Animal and Plant Health Agency – Weybridge New Haw UK
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Ludwig JB, Shi X, Shridhar PB, Roberts EL, DebRoy C, Phebus RK, Bai J, Nagaraja TG. Multiplex PCR Assays for the Detection of One Hundred and Thirty Seven Serogroups of Shiga Toxin-Producing Escherichia coli Associated With Cattle. Front Cell Infect Microbiol 2020; 10:378. [PMID: 32850480 PMCID: PMC7403468 DOI: 10.3389/fcimb.2020.00378] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 06/18/2020] [Indexed: 12/16/2022] Open
Abstract
Escherichia coli carrying prophage with genes that encode for Shiga toxins are categorized as Shiga toxin-producing E. coli (STEC) pathotype. Illnesses caused by STEC in humans, which are often foodborne, range from mild to bloody diarrhea with life-threatening complications of renal failure and hemolytic uremic syndrome and even death, particularly in children. As many as 158 of the total 187 serogroups of E. coli are known to carry Shiga toxin genes, which makes STEC a major pathotype of E. coli. Seven STEC serogroups, called top-7, which include O26, O45, O103, O111, O121, O145, and O157, are responsible for the majority of the STEC-associated human illnesses. The STEC serogroups, other than the top-7, called “non-top-7” have also been associated with human illnesses, more often as sporadic infections. Ruminants, particularly cattle, are principal reservoirs of STEC and harbor the organisms in the hindgut and shed in the feces, which serves as a major source of food and water contaminations. A number of studies have reported on the fecal prevalence of top-7 STEC in cattle feces. However, there is paucity of data on the prevalence of non-top-7 STEC serogroups in cattle feces, generally because of lack of validated detection methods. The objective of our study was to develop and validate 14 sets of multiplex PCR (mPCR) assays targeting serogroup-specific genes to detect 137 non-top-7 STEC serogroups previously reported to be present in cattle feces. Each assay included 7–12 serogroups and primers were designed to amplify the target genes with distinct amplicon sizes for each serogroup that can be readily identified within each assay. The assays were validated with 460 strains of known serogroups. The multiplex PCR assays designed in our study can be readily adapted by most laboratories for rapid identification of strains belonging to the non-top-7 STEC serogroups associated with cattle.
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Affiliation(s)
- Justin B Ludwig
- Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, KS, United States
| | - Xiaorong Shi
- Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, KS, United States
| | - Pragathi B Shridhar
- Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, KS, United States
| | - Elisabeth L Roberts
- E. coli Reference Center, Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA, United States
| | - Chitrita DebRoy
- E. coli Reference Center, Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA, United States
| | - Randy K Phebus
- Department of Animal Sciences and Industry/Food Science Institute, Kansas State University, Manhattan, KS, United States
| | - Jianfa Bai
- Veterinary Diagnostic Laboratory, Industry/Food Science Institute, Kansas State University, Manhattan, KS, United States
| | - T G Nagaraja
- Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, KS, United States
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Shridhar PB, Patel IR, Gangiredla J, Noll LW, Shi X, Bai J, Nagaraja TG. DNA Microarray-Based Genomic Characterization of the Pathotypes of Escherichia coli O26, O45, O103, O111, and O145 Isolated from Feces of Feedlot Cattle †. J Food Prot 2019; 82:395-404. [PMID: 30794460 DOI: 10.4315/0362-028x.jfp-18-393] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Shiga toxin-producing Escherichia coli (STEC) serogroups O26, O45, O103, O111, O121, and O145, referred to as the top six non-O157 serogroups, are responsible for more than 70% of human non-O157 STEC infections in North America. Cattle harbor non-O157 strains in the hindgut and shed them in the feces. The objective of this study was to use the U.S. Food and Drug Administration (FDA) E. coli identification (ECID) DNA microarray to identify the serotype, assess the virulence potential of each, and determine the phylogenetic relationships among five of the six non-O157 E. coli serogroups isolated from feedlot cattle feces. Forty-four strains of STEC, enterohemorrhagic E. coli (EHEC), enteropathogenic E. coli (EPEC), or putative nonpathotype E. coli (NPEC) of cattle origin and five human clinical strains of EHEC were assayed with the FDA-ECID DNA microarray. The cattle strains harbored diverse flagellar genes. The bovine and human strains belonging to serogroups O26, O45, and O103 carried stx1 only, O111 carried both stx1 and stx2, and O145 carried either stx1 or stx2. The strains were also positive for various subtypes of intimin and other adhesins (IrgA homologue adhesin, long polar fimbriae, mannose-specific adhesin, and curli). Both human and cattle strains were positive for LEE-encoded type III secretory system genes and non-LEE-encoded effector genes. SplitsTree4, a program used to determine the phylogenetic relationship among the strains, revealed that the strains within each serogroup clustered according to their pathotype. In addition to genes encoding Shiga toxins, bovine non-O157 E. coli strains possessed other major virulence genes, including those for adhesins, type III secretory system proteins, and plasmid-borne virulence genes, similar to human clinical strains. Because virulence factors encoded by these genes are involved in the pathogenesis of various pathotypes of E. coli, the bovine non-O157 strains could cause human illness. The FDA-ECID DNA microarray assay rapidly provided a profile of the virulence genes for assessment of the virulence potential of each strain.
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Affiliation(s)
- Pragathi B Shridhar
- 1 Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas 66506
| | - Isha R Patel
- 2 U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, Division of Molecular Biology, Laurel, Maryland 20708, USA
| | - Jayanthi Gangiredla
- 2 U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, Division of Molecular Biology, Laurel, Maryland 20708, USA
| | - Lance W Noll
- 1 Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas 66506
| | - Xiaorong Shi
- 1 Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas 66506
| | - Jianfa Bai
- 3 Veterinary Diagnostic Laboratory, Kansas State University, Manhattan, Kansas 66506
| | - T G Nagaraja
- 1 Department of Diagnostic Medicine and Pathobiology, Kansas State University, Manhattan, Kansas 66506
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Fingermann M, Avila L, De Marco MB, Vázquez L, Di Biase DN, Müller AV, Lescano M, Dokmetjian JC, Fernández Castillo S, Pérez Quiñoy JL. OMV-based vaccine formulations against Shiga toxin producing Escherichia coli strains are both protective in mice and immunogenic in calves. Hum Vaccin Immunother 2018; 14:2208-2213. [PMID: 29923791 PMCID: PMC6183318 DOI: 10.1080/21645515.2018.1490381] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Strains of Shiga toxin-producing Escherichia coli (STEC) can cause the severe Hemolytic Uremic Syndrome (HUS). Shiga toxins are protein toxins that bind and kill microvascular cells, damaging vital organs. No specific therapeutics or vaccines have been licensed for use in humans yet. The most common route of infection is by consumption of dairy or farm products contaminated with STEC. Domestic cattle colonized by STEC strains represent the main reservoir, and thus a source of contamination. Outer Membrane Vesicles (OMV) obtained after detergent treatment of gram-negative bacteria have been used over the past decades for producing many licensed vaccines. These nanoparticles are not only multi-antigenic in nature but also potent immunopotentiators and immunomodulators. Formulations based on chemical-inactivated OMV (OMVi) obtained from a virulent STEC strain (O157:H7 serotype) were found to protect against pathogenicity in a murine model and to be immunogenic in calves. These initial studies suggest that STEC-derived OMV has a potential for the formulation of both human and veterinary vaccines.
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Affiliation(s)
| | - Lucía Avila
- a INPB, ANLIS "Dr. Carlos G. Malbrán" , Buenos Aires , Argentina
| | | | - Luciana Vázquez
- b UOCCB, ANLIS "Dr. Carlos G. Malbrán" , Buenos Aires , Argentina
| | | | | | - Mirta Lescano
- a INPB, ANLIS "Dr. Carlos G. Malbrán" , Buenos Aires , Argentina
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5
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Noll LW, Worley JN, Yang X, Shridhar PB, Ludwig JB, Shi X, Bai J, Caragea D, Meng J, Nagaraja TG. Comparative genomics reveals differences in mobile virulence genes of Escherichia coli O103 pathotypes of bovine fecal origin. PLoS One 2018; 13:e0191362. [PMID: 29389941 PMCID: PMC5794082 DOI: 10.1371/journal.pone.0191362] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 01/03/2018] [Indexed: 01/09/2023] Open
Abstract
Escherichia coli O103, harbored in the hindgut and shed in the feces of cattle, can be enterohemorrhagic (EHEC), enteropathogenic (EPEC), or putative non-pathotype. The genetic diversity particularly that of virulence gene profiles within O103 serogroup is likely to be broad, considering the wide range in severity of illness. However, virulence descriptions of the E. coli O103 strains isolated from cattle feces have been primarily limited to major genes, such as Shiga toxin and intimin genes. Less is known about the frequency at which other virulence genes exist or about genes associated with the mobile genetic elements of E. coli O103 pathotypes. Our objective was to utilize whole genome sequencing (WGS) to identify and compare major and putative virulence genes of EHEC O103 (positive for Shiga toxin gene, stx1, and intimin gene, eae; n = 43), EPEC O103 (negative for stx1 and positive for eae; n = 13) and putative non-pathotype O103 strains (negative for stx and eae; n = 13) isolated from cattle feces. Six strains of EHEC O103 from human clinical cases were also included. All bovine EHEC strains (43/43) and a majority of EPEC (12/13) and putative non-pathotype strains (12/13) were O103:H2 serotype. Both bovine and human EHEC strains had significantly larger average genome sizes (P < 0.0001) and were positive for a higher number of adherence and toxin-based virulence genes and genes on mobile elements (prophages, transposable elements, and plasmids) than EPEC or putative non-pathotype strains. The genome size of the three pathotypes positively correlated (R2 = 0.7) with the number of genes carried on mobile genetic elements. Bovine strains clustered phylogenetically by pathotypes, which differed in several key virulence genes. The diversity of E. coli O103 pathotypes shed in cattle feces is likely reflective of the acquisition or loss of virulence genes carried on mobile genetic elements.
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Affiliation(s)
- Lance W. Noll
- Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, Kansas, United States of America
| | - Jay N. Worley
- Joint Institute for Food Safety and Applied Nutrition and Department of Nutrition and Food Science, University of Maryland, College Park, Maryland, United States of America
| | - Xun Yang
- Joint Institute for Food Safety and Applied Nutrition and Department of Nutrition and Food Science, University of Maryland, College Park, Maryland, United States of America
| | - Pragathi B. Shridhar
- Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, Kansas, United States of America
| | - Justin B. Ludwig
- Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, Kansas, United States of America
| | - Xiaorong Shi
- Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, Kansas, United States of America
| | - Jianfa Bai
- Veterinary Diagnostic Laboratory, Kansas State University, Manhattan, Kansas, United States of America
| | - Doina Caragea
- Department of Computing and Information Sciences, Kansas State University, Manhattan, Kansas, United States of America
| | - Jianghong Meng
- Joint Institute for Food Safety and Applied Nutrition and Department of Nutrition and Food Science, University of Maryland, College Park, Maryland, United States of America
| | - T. G. Nagaraja
- Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, Kansas, United States of America
- * E-mail:
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Kim NH, Cho TJ, Rhee MS. Current Interventions for Controlling Pathogenic Escherichia coli. ADVANCES IN APPLIED MICROBIOLOGY 2017; 100:1-47. [PMID: 28732552 DOI: 10.1016/bs.aambs.2017.02.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
This review examined scientific reports and articles published from 2007 to 2016 regarding the major environmental sources of pathogenic Escherichia coli and the routes by which they enter the human gastrointestinal tract. The literature describes novel techniques used to combat pathogenic E. coli transmitted to humans from livestock and agricultural products, food-contact surfaces in processing environments, and food products themselves. Although prevention before contamination is always the best "intervention," many studies aim to identify novel chemical, physical, and biological techniques that inactivate or eliminate pathogenic E. coli cells from breeding livestock, growing crops, and manufactured food products. Such intervention strategies target each stage of the food chain from the perspective of "Farm to Table food safety" and aim to manage major reservoirs of pathogenic E. coli throughout the entire process. Issues related to, and recent trends in, food production must address not only the safety of the food itself but also the safety of those who consume it. Thus, research aims to discover new "natural" antimicrobial agents and to develop "multiple hurdle technology" or other novel technologies that preserve food quality. In addition, this review examines the practical application of recent technologies from the perspective of product quality and safety. It provides comprehensive insight into intervention measures used to ensure food safety, specifically those aimed at pathogenic E. coli.
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Affiliation(s)
- Nam Hee Kim
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
| | - Tae Jin Cho
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
| | - Min Suk Rhee
- Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
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Cull CA, Renter DG, Dewsbury DM, Noll LW, Shridhar PB, Ives SE, Nagaraja TG, Cernicchiaro N. Feedlot- and Pen-Level Prevalence of Enterohemorrhagic Escherichia coli in Feces of Commercial Feedlot Cattle in Two Major U.S. Cattle Feeding Areas. Foodborne Pathog Dis 2017; 14:309-317. [PMID: 28281781 DOI: 10.1089/fpd.2016.2227] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The objective of this study was to determine feedlot- and pen-level fecal prevalence of seven enterohemorrhagic Escherichia coli (EHEC) belonging to serogroups (O26, O45, O103, O111, O121, O145, and O157, or EHEC-7) in feces of feedlot cattle in two feeding areas in the United States. Cattle pens from four commercial feedlots in each of the two major U.S. beef cattle areas were sampled. Up to 16 pen-floor fecal samples were collected from each of 4-6 pens per feedlot, monthly, for a total of three visits per feedlot, from June to August, 2014. Culture procedures including fecal enrichment in E. coli broth, immunomagnetic separation, and plating on selective media, followed by confirmation through polymerase chain reaction (PCR) testing, were conducted. Generalized linear mixed models were fitted to estimate feedlot-, pen-, and sample-level fecal prevalence of EHEC-7 and to evaluate associations between potential demographic and management risk factors with feedlot and within-pen prevalence of EHEC-7. All study feedlots and 31.0% of the study pens had at least one non-O157 EHEC-positive fecal sample, whereas 62.4% of pens tested positive for EHEC O157; sample-level prevalence estimates ranged from 0.0% for EHEC O121 to 18.7% for EHEC O157. Within-pen prevalence of EHEC O157 varied significantly by sampling month; similarly within-pen prevalence of non-O157 EHEC varied significantly by month and by the sex composition of the pen (heifer, steer, or mixed). Feedlot management factors, however, were not significantly associated with fecal prevalence of EHEC-7. Intraclass correlation coefficients for EHEC-7 models indicated that most of the variation occurred between pens, rather than within pens, or between feedlots. Hence, the potential combination of preharvest interventions and pen-level management strategies may have positive food safety impacts downstream along the beef chain.
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Affiliation(s)
- Charley A Cull
- 1 Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University , Manhattan, Kansas
| | - David G Renter
- 1 Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University , Manhattan, Kansas
| | - Diana M Dewsbury
- 1 Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University , Manhattan, Kansas
| | - Lance W Noll
- 1 Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University , Manhattan, Kansas
| | - Pragathi B Shridhar
- 1 Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University , Manhattan, Kansas
| | - Samuel E Ives
- 2 Department of Agricultural Sciences, College of Agriculture and Natural Sciences, West Texas A&M University , Canyon, Texas
| | - Tiruvoor G Nagaraja
- 1 Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University , Manhattan, Kansas
| | - Natalia Cernicchiaro
- 1 Department of Diagnostic Medicine and Pathobiology, College of Veterinary Medicine, Kansas State University , Manhattan, Kansas
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Virulence Gene Profiles and Clonal Relationships of Escherichia coli O26:H11 Isolates from Feedlot Cattle as Determined by Whole-Genome Sequencing. Appl Environ Microbiol 2016; 82:3900-3912. [PMID: 27107118 DOI: 10.1128/aem.00498-16] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 04/15/2016] [Indexed: 12/18/2022] Open
Abstract
UNLABELLED Escherichia coli O26 is the second most important enterohemorrhagic E. coli (EHEC) serogroup worldwide. Serogroup O26 strains are categorized mainly into two groups: enteropathogenic (EPEC) O26, carrying a locus of enterocyte effacement (LEE) and mostly causing mild diarrhea, and Shiga-toxigenic (STEC) O26, which carries the Shiga toxin (STX) gene (stx), responsible for more severe outcomes. stx-negative O26 strains can be further split into two groups. One O26 group differs significantly from O26 EHEC, while the other O26 EHEC-like group shows all the characteristics of EHEC O26 except production of STX. In order to determine the different populations of O26 E. coli present in U.S. cattle, we sequenced 42 O26:H11 strains isolated from feedlot cattle and compared them to 37 O26:H11 genomes available in GenBank. Phylogenetic analysis by whole-genome multilocus sequence typing (wgMLST) showed that O26:H11/H(-) strains in U.S. cattle were highly diverse. Most strains were sequence type 29 (ST29). By wgMLST, two clear lineages could be distinguished among cattle strains. Lineage 1 consisted of O26:H11 EHEC-like strains (ST29) (4 strains) and O26:H11 EHEC strains (ST21) (2 strains), and lineage 2 (36 strains) consisted of O26:H11 EPEC strains (ST29). Overall, our analysis showed U.S. cattle carried pathogenic (ST21; stx1 (+) ehxA(+) toxB(+)) and also potentially pathogenic (ST29; ehxA(+) toxB(+)) O26:H11 E. coli strains. Furthermore, in silico analysis showed that 70% of the cattle strains carried at least one antimicrobial resistance gene. Our results showed that whole-genome sequence analysis is a robust and valid approach to identify and genetically characterize E. coli O26:H11, which is of importance for food safety and public health. IMPORTANCE Escherichia coli O26 is the second most important type of enterohemorrhagic E. coli (EHEC) worldwide. Serogroup O26 strains are categorized into two groups: enteropathogenic (EPEC) carrying LEE, causing mild diarrhea, and Shiga toxigenic (STEC) carrying the stx gene, responsible for more severe outcomes. However, there are currently problems in distinguishing one group from the other. Furthermore, several O26 stx-negative strains are consistently misidentified as either EHEC-like or EPEC. The use of whole-genome sequence (WGS) analysis of O26 strains from cattle in the United States (i) allowed identification of O26 strains present in U.S. cattle, (ii) determined O26 strain diversity, (iii) solved the misidentification problem, and (iv) screened for the presence of antimicrobial resistance and virulence genes in the strains. This study provided a framework showing how to easily and rapidly use WGS information to identify and genetically characterize E. coli O26:H11, which is important for food safety and public health.
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Ison SA, Delannoy S, Bugarel M, Nagaraja TG, Renter DG, den Bakker HC, Nightingale KK, Fach P, Loneragan GH. Targeted Amplicon Sequencing for Single-Nucleotide-Polymorphism Genotyping of Attaching and Effacing Escherichia coli O26:H11 Cattle Strains via a High-Throughput Library Preparation Technique. Appl Environ Microbiol 2016; 82:640-9. [PMID: 26567298 PMCID: PMC4711113 DOI: 10.1128/aem.03182-15] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2015] [Accepted: 11/04/2015] [Indexed: 12/31/2022] Open
Abstract
Enterohemorrhagic Escherichia coli (EHEC) O26:H11, a serotype within Shiga toxin-producing E. coli (STEC) that causes severe human disease, has been considered to have evolved from attaching and effacing E. coli (AEEC) O26:H11 through the acquisition of a Shiga toxin-encoding gene. Targeted amplicon sequencing using next-generation sequencing technology of 48 phylogenetically informative single-nucleotide polymorphisms (SNPs) and three SNPs differentiating Shiga toxin-positive (stx-positive) strains from Shiga toxin-negative (stx-negative) strains were used to infer the phylogenetic relationships of 178 E. coli O26:H11 strains (6 stx-positive strains and 172 stx-negative AEEC strains) from cattle feces to 7 publically available genomes of human clinical strains. The AEEC cattle strains displayed synonymous SNP genotypes with stx2-positive sequence type 29 (ST29) human O26:H11 strains, while stx1 ST21 human and cattle strains clustered separately, demonstrating the close phylogenetic relatedness of these Shiga toxin-negative AEEC cattle strains and human clinical strains. With the exception of seven stx-negative strains, five of which contained espK, three stx-related SNPs differentiated the STEC strains from non-STEC strains, supporting the hypothesis that these AEEC cattle strains could serve as a potential reservoir for new or existing pathogenic human strains. Our results support the idea that targeted amplicon sequencing for SNP genotyping expedites strain identification and genetic characterization of E. coli O26:H11, which is important for food safety and public health.
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Affiliation(s)
- Sarah A Ison
- Department of Animal and Food Sciences, Texas Tech University, Lubbock, Texas, USA
| | - Sabine Delannoy
- ANSES Food Safety Laboratory, Platform IdentyPath, Université Paris-Est, Maisons-Alfort, France
| | - Marie Bugarel
- Department of Animal and Food Sciences, Texas Tech University, Lubbock, Texas, USA
| | - Tiruvoor G Nagaraja
- Department of Diagnostic Medicine Pathobiology, Kansas State University, Manhattan, Kansas, USA
| | - David G Renter
- Department of Diagnostic Medicine Pathobiology, Kansas State University, Manhattan, Kansas, USA
| | - Henk C den Bakker
- Department of Animal and Food Sciences, Texas Tech University, Lubbock, Texas, USA
| | - Kendra K Nightingale
- Department of Animal and Food Sciences, Texas Tech University, Lubbock, Texas, USA
| | - Patrick Fach
- ANSES Food Safety Laboratory, Platform IdentyPath, Université Paris-Est, Maisons-Alfort, France
| | - Guy H Loneragan
- Department of Animal and Food Sciences, Texas Tech University, Lubbock, Texas, USA
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Noll LW, Baumgartner WC, Shridhar PB, Cull CA, Dewsbury DM, Shi X, Cernicchiaro N, Renter DG, Nagaraja TG. Pooling of Immunomagnetic Separation Beads Does Not Affect Detection Sensitivity of Six Major Serogroups of Shiga Toxin-Producing Escherichia coli in Cattle Feces. J Food Prot 2016; 79:59-65. [PMID: 26735030 DOI: 10.4315/0362-028x.jfp-15-236] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Shiga toxin-producing Escherichia coli (STEC) of the serogroups O26, O45, O103, O111, O121, and O145, often called non-O157 STEC, are foodborne pathogens. Cattle are asymptomatic reservoirs for STEC; the organisms reside in the hindgut and are shed in the feces, which serve as the source of food product contaminations. Culture-based detection of non-O157 STEC involves an immunomagnetic separation (IMS) step to capture the specific serogroups in complex matrices, such as feces. The IMS procedure is time consuming and labor intensive because of the need to subject each fecal sample to six individual beads. Therefore, our objective was to evaluate whether pooling of IMS beads affects sensitivity of non-O157 STEC detection compared with using individual IMS beads. The evaluation was done by comparing detection of serogroups in feces spiked with pure cultures (experiments 1 and 2) and from feces (n = 384) of naturally shedding cattle (experiment 3). In spiked fecal samples, detection with pools of three, four, six, or seven beads was similar to, or at times higher than, detection with individual IMS beads. In experiment 3, the proportions of fecal samples that tested positive for the six serogroups as detected by individual or pooled beads were similar. Based on noninferiority tests, detection with pooled beads was not substantially inferior to detection with individual beads (P > 0.05). In conclusion, the pooling of IMS beads is a better option for detection of STEC serogroups in fecal samples compared with individual beads because the procedure saves time and labor and has the prospect of a higher throughput.
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Affiliation(s)
- Lance W Noll
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, Kansas 66506, USA
| | - William C Baumgartner
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, Kansas 66506, USA
| | - Pragathi B Shridhar
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, Kansas 66506, USA
| | - Charley A Cull
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, Kansas 66506, USA
| | - Diana M Dewsbury
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, Kansas 66506, USA
| | - Xiaorong Shi
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, Kansas 66506, USA
| | - Natalia Cernicchiaro
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, Kansas 66506, USA
| | - David G Renter
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, Kansas 66506, USA
| | - T G Nagaraja
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, 1800 Denison Avenue, Manhattan, Kansas 66506, USA.
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Krüger A, Lucchesi PMA, Sanso AM, Etcheverría AI, Bustamante AV, Burgán J, Fernández L, Fernández D, Leotta G, Friedrich AW, Padola NL, Rossen JWA. Genetic characterization of Shiga toxin-producing Escherichia coli O26:H11 strains isolated from animal, food, and clinical samples. Front Cell Infect Microbiol 2015; 5:74. [PMID: 26539413 PMCID: PMC4612136 DOI: 10.3389/fcimb.2015.00074] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 10/05/2015] [Indexed: 11/16/2022] Open
Abstract
The Shiga-toxin producing Escherichia coli (STEC) may cause serious illness in human. Here we analyze O26:H11 strains known to be among the most reported STEC strains causing human infections. Genetic characterization of strains isolated from animal, food, and clinical specimens in Argentina showed that most carried either stx1a or stx2a subtypes. Interestingly, stx2a-positive O26:H11 rarely isolated from cattle in other countries showed to be an important proportion of O26:H11 strains circulating in cattle and food in our region. Seventeen percent of the isolates harbored more than one gene associated with antimicrobial resistance. In addition to stx, all strains contained the virulence genes eae-β, tir, efa, iha, espB, cif, espA, espF, espJ, nleA, nleB, nleC, and iss; and all except one contained ehxA, espP, and cba genes. On the other hand, toxB and espI genes were exclusively observed in stx2-positive isolates, whereas katP was only found in stx1a-positive isolates. Our results show that O26:H11 STEC strains circulating in Argentina, including those isolated from humans, cattle, and meat products, present a high pathogenic potential, and evidence that cattle can be a reservoir of O26:H11 strains harboring stx2a.
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Affiliation(s)
- Alejandra Krüger
- Laboratorio de Inmunoquímica y Biotecnología, Facultad de Ciencias Veterinarias, Centro de Investigación Veterinaria de Tandil, Consejo Nacional de Investigaciones Científicas y Técnicas, Comisión de Investigaciones Científicas, Universidad Nacional del Centro de la Provincia de Buenos Aires Tandil, Argentina
| | - Paula M A Lucchesi
- Laboratorio de Inmunoquímica y Biotecnología, Facultad de Ciencias Veterinarias, Centro de Investigación Veterinaria de Tandil, Consejo Nacional de Investigaciones Científicas y Técnicas, Comisión de Investigaciones Científicas, Universidad Nacional del Centro de la Provincia de Buenos Aires Tandil, Argentina
| | - A Mariel Sanso
- Laboratorio de Inmunoquímica y Biotecnología, Facultad de Ciencias Veterinarias, Centro de Investigación Veterinaria de Tandil, Consejo Nacional de Investigaciones Científicas y Técnicas, Comisión de Investigaciones Científicas, Universidad Nacional del Centro de la Provincia de Buenos Aires Tandil, Argentina
| | - Analía I Etcheverría
- Laboratorio de Inmunoquímica y Biotecnología, Facultad de Ciencias Veterinarias, Centro de Investigación Veterinaria de Tandil, Consejo Nacional de Investigaciones Científicas y Técnicas, Comisión de Investigaciones Científicas, Universidad Nacional del Centro de la Provincia de Buenos Aires Tandil, Argentina
| | - Ana V Bustamante
- Laboratorio de Inmunoquímica y Biotecnología, Facultad de Ciencias Veterinarias, Centro de Investigación Veterinaria de Tandil, Consejo Nacional de Investigaciones Científicas y Técnicas, Comisión de Investigaciones Científicas, Universidad Nacional del Centro de la Provincia de Buenos Aires Tandil, Argentina
| | - Julia Burgán
- Laboratorio de Inmunoquímica y Biotecnología, Facultad de Ciencias Veterinarias, Centro de Investigación Veterinaria de Tandil, Consejo Nacional de Investigaciones Científicas y Técnicas, Comisión de Investigaciones Científicas, Universidad Nacional del Centro de la Provincia de Buenos Aires Tandil, Argentina
| | - Luciana Fernández
- Laboratorio de Inmunoquímica y Biotecnología, Facultad de Ciencias Veterinarias, Centro de Investigación Veterinaria de Tandil, Consejo Nacional de Investigaciones Científicas y Técnicas, Comisión de Investigaciones Científicas, Universidad Nacional del Centro de la Provincia de Buenos Aires Tandil, Argentina
| | - Daniel Fernández
- Laboratorio de Inmunoquímica y Biotecnología, Facultad de Ciencias Veterinarias, Centro de Investigación Veterinaria de Tandil, Consejo Nacional de Investigaciones Científicas y Técnicas, Comisión de Investigaciones Científicas, Universidad Nacional del Centro de la Provincia de Buenos Aires Tandil, Argentina
| | - Gerardo Leotta
- Línea Seguridad Alimentaria, Instituto de Genética Veterinaria Ing. F.N. Dulout, Consejo Nacional de Investigaciones Científicas y Técnicas La Plata, Argentina
| | - Alexander W Friedrich
- Department of Medical Microbiology, University Medical Center Groningen, University of Groningen Groningen, Netherlands
| | - Nora L Padola
- Laboratorio de Inmunoquímica y Biotecnología, Facultad de Ciencias Veterinarias, Centro de Investigación Veterinaria de Tandil, Consejo Nacional de Investigaciones Científicas y Técnicas, Comisión de Investigaciones Científicas, Universidad Nacional del Centro de la Provincia de Buenos Aires Tandil, Argentina
| | - John W A Rossen
- Department of Medical Microbiology, University Medical Center Groningen, University of Groningen Groningen, Netherlands
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12
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Desin TS, Townsend HG, Potter AA. Antibodies Directed against Shiga-Toxin Producing Escherichia coli Serotype O103 Type III Secreted Proteins Block Adherence of Heterologous STEC Serotypes to HEp-2 Cells. PLoS One 2015; 10:e0139803. [PMID: 26451946 PMCID: PMC4599963 DOI: 10.1371/journal.pone.0139803] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 09/17/2015] [Indexed: 11/25/2022] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) serotype O103 is a zoonotic pathogen that is capable of causing hemorrhagic colitis and hemolytic uremic syndrome (HUS) in humans. The main animal reservoir for STEC is ruminants and hence reducing the levels of this pathogen in cattle could ultimately lower the risk of STEC infection in humans. During the process of infection, STECO103 uses a Type III Secretion System (T3SS) to secrete effector proteins (T3SPs) that result in the formation of attaching and effacing (A/E) lesions. Vaccination of cattle with STEC serotype O157 T3SPs has previously been shown to be effective in reducing shedding of STECO157 in a serotype-specific manner. In this study, we tested the ability of rabbit polyclonal sera against individual STECO103 T3SPs to block adherence of the organism to HEp-2 cells. Our results demonstrate that pooled sera against EspA, EspB, EspF, NleA and Tir significantly lowered the adherence of STECO103 relative to pre-immune sera. Likewise, pooled anti-STECO103 sera were also able to block adherence by STECO157. Vaccination of mice with STECO103 recombinant proteins induced strong IgG antibody responses against EspA, EspB, NleA and Tir but not against EspF. However, the vaccine did not affect fecal shedding of STECO103 compared to the PBS vaccinated group over the duration of the experiment. Cross reactivity studies using sera against STECO103 recombinant proteins revealed a high degree of cross reactivity with STECO26 and STECO111 proteins implying that sera against STECO103 proteins could potentially provide neutralization of attachment to epithelial cells by heterologous STEC serotypes.
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Affiliation(s)
- Taseen S. Desin
- Vaccine & Infectious Disease Organization–International Vaccine Center, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
- * E-mail:
| | - Hugh G. Townsend
- Vaccine & Infectious Disease Organization–International Vaccine Center, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Andrew A. Potter
- Vaccine & Infectious Disease Organization–International Vaccine Center, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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13
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Noll LW, Shridhar PB, Dewsbury DM, Shi X, Cernicchiaro N, Renter DG, Nagaraja TG. A Comparison of Culture- and PCR-Based Methods to Detect Six Major Non-O157 Serogroups of Shiga Toxin-Producing Escherichia coli in Cattle Feces. PLoS One 2015; 10:e0135446. [PMID: 26270482 PMCID: PMC4536017 DOI: 10.1371/journal.pone.0135446] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Accepted: 07/23/2015] [Indexed: 11/20/2022] Open
Abstract
Culture-based methods to detect the six major non-O157 (O26, O45, O103, O111, O121 and O145) Shiga toxin-producing E. coli (STEC) are not well established. Our objectives of this study were to develop a culture-based method to detect the six non-O157 serogroups in cattle feces and compare the detection with a PCR method. Fecal samples (n = 576) were collected in a feedlot from 24 pens during a 12-week period and enriched in E. coli broth at 40° C for 6 h. Enriched samples were subjected to immunomagnetic separation, spread-plated onto a selective chromogenic medium, and initially pooled colonies, and subsequently, single colonies were tested by a multiplex PCR targeting six serogroups and four virulence genes, stx1, stx2, eae, and ehxA (culture method). Fecal suspensions, before and after enrichment, were also tested by a multiplex PCR targeting six serogroups and four virulence genes (PCR method). There was no difference in the proportions of fecal samples that tested positive (74.3 vs. 77.4%) for one or more of the six serogroups by either culture or the PCR method. However, each method detected one or more of the six serogroups in samples that were negative by the other method. Both culture method and PCR indicated that O26, O45, and O103 were the dominant serogroups. Higher proportions (P < 0.05) of fecal samples were positive for O26 (44.4 vs. 22.7%) and O121 (22.9 vs. 2.3%) serogroups by PCR than by the culture method. None of the fecal samples contained more than four serogroups. Only a small proportion of the six serogroups (23/640; 3.6%) isolated carried Shiga toxin genes. The culture method and the PCR method detected all six serogroups in samples negative by the other method, highlighting the importance of subjecting fecal samples to both methods for accurate detection of the six non-O157 STEC in cattle feces.
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Affiliation(s)
- Lance W. Noll
- Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, Kansas, United States of America
| | - Pragathi B. Shridhar
- Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, Kansas, United States of America
| | - Diana M. Dewsbury
- Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, Kansas, United States of America
| | - Xiaorong Shi
- Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, Kansas, United States of America
| | - Natalia Cernicchiaro
- Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, Kansas, United States of America
| | - David G. Renter
- Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, Kansas, United States of America
| | - T. G. Nagaraja
- Department of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, Kansas, United States of America
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14
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Ghunaim H, Desin TS. Potential Impact of Food Safety Vaccines on Health Care Costs. Foodborne Pathog Dis 2015; 12:733-40. [PMID: 26111256 DOI: 10.1089/fpd.2014.1924] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Foodborne pathogens continue to cause several outbreaks every year in many parts of the world. Among the bacterial pathogens involved, Shiga toxin-producing Escherichia coli, Campylobacter jejuni, and nontyphoidal Salmonella species cause a significant number of human infections worldwide, resulting in a huge annual economic burden that amounts to millions of dollars in health care costs. Human infections are primarily caused by the consumption of contaminated food. Vaccination of food-producing animals is an attractive, cost-effective strategy to lower the levels of these pathogens that will ultimately result in a safer food supply and fewer human infections. However, producers are often reluctant to routinely vaccinate animals against these pathogens since they do not cause any detectable clinical symptoms. This review highlights recent approaches used to develop effective food safety vaccines and the potential impact these vaccines might have on health care costs.
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Affiliation(s)
- Haitham Ghunaim
- 1 Department of Health Sciences, College of Arts and Science, Qatar University , Doha, Qatar
| | - Taseen S Desin
- 2 Basic Sciences Department, College of Science & Health Professions, King Saud bin Abdulaziz University for Health Sciences , Riyadh, Saudi Arabia
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15
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Ison SA, Delannoy S, Bugarel M, Nightingale KK, Webb HE, Renter DG, Nagaraja TG, Loneragan GH, Fach P. Genetic Diversity and Pathogenic Potential of Attaching and Effacing Escherichia coli O26:H11 Strains Recovered from Bovine Feces in the United States. Appl Environ Microbiol 2015; 81:3671-8. [PMID: 25795673 PMCID: PMC4421050 DOI: 10.1128/aem.00397-15] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Accepted: 03/15/2015] [Indexed: 12/28/2022] Open
Abstract
Escherichia coli O26 has been identified as the most common non-O157 Shiga toxin-producing E. coli (STEC) serogroup to cause human illnesses in the United States and has been implicated in outbreaks around the world. E. coli has high genomic plasticity, which facilitates the loss or acquisition of virulence genes. Attaching and effacing E. coli (AEEC) O26 strains have frequently been isolated from bovine feces, and there is a need to better characterize the relatedness of these strains to defined molecular pathotypes and to describe the extent of their genetic diversity. High-throughput real-time PCR was used to screen 178 E. coli O26 isolates from a single U.S. cattle feedlot, collected from May to July 2011, for the presence or absence of 25 O26 serogroup-specific and virulence-associated markers. The selected markers were capable of distinguishing these strains into molecularly defined groups (yielding 18 unique marker combinations). Analysis of the clustered regularly interspaced short palindromic repeat 1 (CRISPR1) and CRISPR2a loci further discriminated isolates into 24 CRISPR types. The combination of molecular markers and CRISPR typing provided 20.8% diversity. The recent CRISPR PCR target SP_O26-E, which was previously identified only in stx2-positive O26:H11 human clinical strains, was identified in 96.4% (161/167 [95% confidence interval, 99.2 to 93.6%]) of the stx-negative AEEC O26:H11 bovine fecal strains. This supports that these stx-negative strains may have previously contained a prophage carrying stx or could acquire this prophage, thus possibly giving them the potential to become pathogenic to humans. These results show that investigation of specific genetic markers may further elucidate our understanding of the genetic diversity of AEEC O26 strains in bovine feces.
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Affiliation(s)
- Sarah A Ison
- Texas Tech University, Department of Animal and Food Sciences, Lubbock, Texas, USA
| | - Sabine Delannoy
- French Agency for Food, Environmental and Occupational Health and Safety, Food Safety Laboratory, Platform IdentyPath, Maisons-Alfort, France
| | - Marie Bugarel
- Texas Tech University, Department of Animal and Food Sciences, Lubbock, Texas, USA
| | - Kendra K Nightingale
- Texas Tech University, Department of Animal and Food Sciences, Lubbock, Texas, USA
| | - Hattie E Webb
- Texas Tech University, Department of Animal and Food Sciences, Lubbock, Texas, USA
| | - David G Renter
- Kansas State University, Department of Diagnostic Medicine Pathobiology, Manhattan, Kansas, USA
| | - Tiruvoor G Nagaraja
- Kansas State University, Department of Diagnostic Medicine Pathobiology, Manhattan, Kansas, USA
| | - Guy H Loneragan
- Texas Tech University, Department of Animal and Food Sciences, Lubbock, Texas, USA
| | - Patrick Fach
- French Agency for Food, Environmental and Occupational Health and Safety, Food Safety Laboratory, Platform IdentyPath, Maisons-Alfort, France
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McNeilly TN, Mitchell MC, Corbishley A, Nath M, Simmonds H, McAteer SP, Mahajan A, Low JC, Smith DGE, Huntley JF, Gally DL. Optimizing the Protection of Cattle against Escherichia coli O157:H7 Colonization through Immunization with Different Combinations of H7 Flagellin, Tir, Intimin-531 or EspA. PLoS One 2015; 10:e0128391. [PMID: 26020530 PMCID: PMC4447243 DOI: 10.1371/journal.pone.0128391] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 04/24/2015] [Indexed: 11/19/2022] Open
Abstract
Enterohemorrhagic Escherichia coli (EHEC) are important human pathogens, causing hemorrhagic colitis and hemolytic uraemic syndrome in humans. E. coli O157:H7 is the most common serotype associated with EHEC infections worldwide, although other non-O157 serotypes cause life-threatening infections. Cattle are a main reservoir of EHEC and intervention strategies aimed at limiting EHEC excretion from cattle are predicted to lower the risk of human infection. We have previously shown that immunization of calves with recombinant versions of the type III secretion system (T3SS)-associated proteins EspA, intimin and Tir from EHEC O157:H7 significantly reduced shedding of EHEC O157 from experimentally-colonized calves, and that protection could be augmented by the addition of H7 flagellin to the vaccine formulation. The main aim of the present study was to optimize our current EHEC O157 subunit vaccine formulations by identifying the key combinations of these antigens required for protection. A secondary aim was to determine if vaccine-induced antibody responses exhibited cross-reactive potential with antigens from other EHEC serotypes. Immunization with EspA, intimin and Tir resulted in a reduction in mean EHEC O157 shedding following challenge, but not the mean proportion of calves colonized. Removal of Tir resulted in more prolonged shedding compared with all other groups, whereas replacement of Tir with H7 flagellin resulted in the highest levels of protection, both in terms of reducing both mean EHEC O157 shedding and the proportion of colonized calves. Immunization of calves with recombinant EHEC O157 EspA, intimin and Tir resulted in the generation of antibodies capable of cross-reacting with antigens from non-O157 EHEC serotypes, suggesting that immunization with these antigens may provide a degree of cross-protection against other EHEC serotypes. Further studies are now required to test the efficacy of these vaccines in the field, and to formally test the cross-protective potential of the vaccines against other non-O157 EHEC.
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Affiliation(s)
- Tom N. McNeilly
- Moredun Research Institute, Edinburgh, United Kingdom
- * E-mail:
| | | | - Alexander Corbishley
- Moredun Research Institute, Edinburgh, United Kingdom
- Division of Immunity and Infection, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Mintu Nath
- Biomathematics and Statistics Scotland, Edinburgh, United Kingdom
| | - Hannah Simmonds
- Division of Immunity and Infection, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Sean P. McAteer
- Division of Immunity and Infection, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Arvind Mahajan
- Division of Immunity and Infection, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - J. Christopher Low
- Division of Immunity and Infection, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - David G. E. Smith
- Moredun Research Institute, Edinburgh, United Kingdom
- Institute of Infection, Immunity & Inflammation, University of Glasgow, Glasgow, United Kingdom
| | | | - David L. Gally
- Division of Immunity and Infection, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
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17
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Rahal EA, Fadlallah SM, Nassar FJ, Kazzi N, Matar GM. Approaches to treatment of emerging Shiga toxin-producing Escherichia coli infections highlighting the O104:H4 serotype. Front Cell Infect Microbiol 2015; 5:24. [PMID: 25853096 PMCID: PMC4364364 DOI: 10.3389/fcimb.2015.00024] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Accepted: 03/04/2015] [Indexed: 11/13/2022] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) are a group of diarrheagenic bacteria associated with foodborne outbreaks. Infection with these agents may result in grave sequelae that include fatality. A large number of STEC serotypes has been identified to date. E. coli serotype O104:H4 is an emerging pathogen responsible for a 2011 outbreak in Europe that resulted in over 4000 infections and 50 deaths. STEC pathogenicity is highly reliant on the production of one or more Shiga toxins that can inhibit protein synthesis in host cells resulting in a cytotoxicity that may affect various organ systems. Antimicrobials are usually avoided in the treatment of STEC infections since they are believed to induce bacterial cell lysis and the release of stored toxins. Some antimicrobials have also been reported to enhance toxin synthesis and production from these organisms. Various groups have attempted alternative treatment approaches including the administration of toxin-directed antibodies, toxin-adsorbing polymers, probiotic agents and natural remedies. The utility of antibiotics in treating STEC infections has also been reconsidered in recent years with certain modalities showing promise.
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Affiliation(s)
- Elias A Rahal
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut Beirut, Lebanon
| | - Sukayna M Fadlallah
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut Beirut, Lebanon
| | - Farah J Nassar
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut Beirut, Lebanon
| | - Natalie Kazzi
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut Beirut, Lebanon
| | - Ghassan M Matar
- Department of Experimental Pathology, Immunology and Microbiology, Faculty of Medicine, American University of Beirut Beirut, Lebanon
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18
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Norman KN, Clawson ML, Strockbine NA, Mandrell RE, Johnson R, Ziebell K, Zhao S, Fratamico PM, Stones R, Allard MW, Bono JL. Comparison of whole genome sequences from human and non-human Escherichia coli O26 strains. Front Cell Infect Microbiol 2015; 5:21. [PMID: 25815275 PMCID: PMC4356229 DOI: 10.3389/fcimb.2015.00021] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 02/21/2015] [Indexed: 11/13/2022] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) O26 is the second leading E. coli serogroup responsible for human illness outbreaks behind E. coli O157:H7. Recent outbreaks have been linked to emerging pathogenic O26:H11 strains harboring stx 2 only. Cattle have been recognized as an important reservoir of O26 strains harboring stx 1; however the reservoir of these emerging stx 2 strains is unknown. The objective of this study was to identify nucleotide polymorphisms in human and cattle-derived strains in order to compare differences in polymorphism derived genotypes and virulence gene profiles between the two host species. Whole genome sequencing was performed on 182 epidemiologically unrelated O26 strains, including 109 human-derived strains and 73 non-human-derived strains. A panel of 289 O26 strains (241 STEC and 48 non-STEC) was subsequently genotyped using a set of 283 polymorphisms identified by whole genome sequencing, resulting in 64 unique genotypes. Phylogenetic analyses identified seven clusters within the O26 strains. The seven clusters did not distinguish between isolates originating from humans or cattle; however, clusters did correspond with particular virulence gene profiles. Human and non-human-derived strains harboring stx 1 clustered separately from strains harboring stx 2, strains harboring eae, and non-STEC strains. Strains harboring stx 2 were more closely related to non-STEC strains and strains harboring eae than to strains harboring stx 1. The finding of human and cattle-derived strains with the same polymorphism derived genotypes and similar virulence gene profiles, provides evidence that similar strains are found in cattle and humans and transmission between the two species may occur.
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Affiliation(s)
- Keri N. Norman
- U.S. Meat Animal Research Center, United States Department of Agriculture, Agricultural Research ServiceClay Center, NE, USA
| | - Michael L. Clawson
- U.S. Meat Animal Research Center, United States Department of Agriculture, Agricultural Research ServiceClay Center, NE, USA
| | - Nancy A. Strockbine
- Division of Foodborne, Waterborne and Environmental Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and PreventionAtlanta, GA, USA
| | - Robert E. Mandrell
- Western Regional Research Center, United States Department of Agriculture, Agricultural Research ServiceAlbany, CA, USA
| | - Roger Johnson
- Laboratory for Foodborne Zoonoses, Public Health Agency of CanadaGuelph, ON, Canada
| | - Kim Ziebell
- Laboratory for Foodborne Zoonoses, Public Health Agency of CanadaGuelph, ON, Canada
| | - Shaohua Zhao
- Division of Animal and Food Microbiology, Center for Veterinary Medicine, Food and Drug AdministrationLaurel, MD, USA
| | - Pina M. Fratamico
- Eastern Regional Research Center, United States Department of Agriculture, Agricultural Research ServiceWyndmoor, PA, USA
| | - Robert Stones
- Food and Environment Research AgencySand Hutton, York, UK
| | - Marc W. Allard
- Division of Microbiology, Center for Food Safety and Applied Nutrition, Office of Regulatory Science, Food and Drug AdministrationCollege Park, MD, USA
| | - James L. Bono
- U.S. Meat Animal Research Center, United States Department of Agriculture, Agricultural Research ServiceClay Center, NE, USA
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