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Meng J, Ding J, Wang W, Gu B, Zhou F, Wu D, Fu X, Liu J. Reversal of gentamicin sulfate resistance in avian pathogenic Escherichia coli by matrine combined with berberine hydrochloride. Arch Microbiol 2024; 206:292. [PMID: 38849633 DOI: 10.1007/s00203-024-04021-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Accepted: 05/27/2024] [Indexed: 06/09/2024]
Abstract
In recent years, the evolution of antibiotic resistance has led to the inefficacy of several antibiotics, and the reverse of resistance was a novel method to solve this problem. We previously demonstrated that matrine (Mat) and berberine hydrochloride (Ber) had a synergistic effect against multidrug-resistant Escherichia coli (MDREC). This study aimed to demonstrate the effect of Mat combined with Ber in reversing the resistance of MDREC. The MDREC was sequenced passaged in the presence of Mat, Ber, and a combination of Mat and Ber, which did not affect its growth. The reverse rate was up to 39.67% after MDREC exposed to Mat + Ber for 15 days. The strain that reversed resistance was named drug resistance reversed E. coli (DRREC) and its resistance to ampicillin, streptomycin, gentamicin, and tetracycline was reversed. The MIC of Gentamicin Sulfate (GS) against DRREC decreased 128-fold to 0.63 µg/mL, and it was stable within 20 generations. Furthermore, the susceptible phenotype of DRREC remained stable within 20 generations, as well. The LD50 of DRREC for chickens was 8.69 × 109 CFU/mL. qRT-PCR assays revealed that the transcript levels of antibiotic-resistant genes and virulence genes in the DRREC strain were significantly lower than that in the MDREC strain (P < 0.05). In addition, GS decreased the death, decreased the bacterial loading in organs, alleviated the injury of the spleen and liver, and decreased the cytokine levels in the chickens infected by the DRREC strain. In contrast, the therapeutic effect of GS in chickens infected with MDREC was not as evident. These findings suggest that the combination of Mat and Ber has potential for reversing resistance to MDREC.
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Affiliation(s)
- Jinwu Meng
- MOE Joint International Research Laboratory of Animal Health and Food Safety and Institute of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, P R China
| | - Jinxue Ding
- MOE Joint International Research Laboratory of Animal Health and Food Safety and Institute of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, P R China
| | - Weiran Wang
- MOE Joint International Research Laboratory of Animal Health and Food Safety and Institute of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, P R China
| | - Bolin Gu
- MOE Joint International Research Laboratory of Animal Health and Food Safety and Institute of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, P R China
| | - Fanting Zhou
- MOE Joint International Research Laboratory of Animal Health and Food Safety and Institute of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, P R China
| | - Desheng Wu
- MOE Joint International Research Laboratory of Animal Health and Food Safety and Institute of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, P R China
| | - Xiang Fu
- MOE Joint International Research Laboratory of Animal Health and Food Safety and Institute of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, P R China
| | - Jiaguo Liu
- MOE Joint International Research Laboratory of Animal Health and Food Safety and Institute of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, P R China.
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Chevez ZR, Dunn LL, da Silva ALBR, Rodrigues C. Prevalence of STEC virulence markers and Salmonella as a function of abiotic factors in agricultural water in the southeastern United States. Front Microbiol 2024; 15:1320168. [PMID: 38832116 PMCID: PMC11144861 DOI: 10.3389/fmicb.2024.1320168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Accepted: 05/06/2024] [Indexed: 06/05/2024] Open
Abstract
Fresh produce can be contaminated by enteric pathogens throughout crop production, including through contact with contaminated agricultural water. The most common outbreaks and recalls in fresh produce are due to contamination by Salmonella enterica and Shiga toxin-producing E. coli (STEC). Thus, the objectives of this study were to investigate the prevalence of markers for STEC (wzy, hly, fliC, eaeA, rfbE, stx-I, stx-II) and Salmonella (invA) in surface water sources (n = 8) from produce farms in Southwest Georgia and to determine correlations among the prevalence of virulence markers for STEC, water nutrient profile, and environmental factors. Water samples (500 mL) from eight irrigation ponds were collected from February to December 2021 (n = 88). Polymerase chain reaction (PCR) was used to screen for Salmonella and STEC genes, and Salmonella samples were confirmed by culture-based methods. Positive samples for Salmonella were further serotyped. Particularly, Salmonella was detected in 6/88 (6.81%) water samples from all ponds, and the following 4 serotypes were detected: Saintpaul 3/6 (50%), Montevideo 1/6 (16.66%), Mississippi 1/6 (16.66%), and Bareilly 1/6 (16.66%). Salmonella isolates were only found in the summer months (May-Aug.). The most prevalent STEC genes were hly 77/88 (87.50%) and stx-I 75/88 (85.22%), followed by fliC 54/88 (61.63%), stx-II 41/88 (46.59%), rfbE 31/88 (35.22%), and eaeA 28/88 (31.81%). The wzy gene was not detected in any of the samples. Based on a logistic regression analysis, the odds of codetection for STEC virulence markers (stx-I, stx-II, and eaeA) were negatively correlated with calcium and relative humidity (p < 0.05). A conditional forest analysis was performed to assess predictive performance (AUC = 0.921), and the top predictors included humidity, nitrate, calcium, and solar radiation. Overall, information from this research adds to a growing body of knowledge regarding the risk that surface water sources pose to produce grown in subtropical environmental conditions and emphasizes the importance of understanding the use of abiotic factors as a holistic approach to understanding the microbial quality of water.
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Affiliation(s)
- Zoila R. Chevez
- Department of Horticulture, Auburn University, Auburn, AL, United States
| | - Laurel L. Dunn
- Department of Food Science and Technology, University of Georgia, Athens, GA, United States
| | | | - Camila Rodrigues
- Department of Horticulture, Auburn University, Auburn, AL, United States
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Kalalah AA, Koenig SSK, Feng P, Bosilevac JM, Bono JL, Eppinger M. Pathogenomes of Shiga Toxin Positive and Negative Escherichia coli O157:H7 Strains TT12A and TT12B: Comprehensive Phylogenomic Analysis Using Closed Genomes. Microorganisms 2024; 12:699. [PMID: 38674643 PMCID: PMC11052207 DOI: 10.3390/microorganisms12040699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2024] [Revised: 03/18/2024] [Accepted: 03/26/2024] [Indexed: 04/28/2024] Open
Abstract
Shiga toxin-producing Escherichia coli are zoonotic pathogens that cause food-borne human disease. Among these, the O157:H7 serotype has evolved from an enteropathogenic O55:H7 ancestor through the displacement of the somatic gene cluster and recurrent toxigenic conversion by Shiga toxin-converting bacteriophages. However, atypical strains that lack the Shiga toxin, the characteristic virulence hallmark, are circulating in this lineage. For this study, we analyzed the pathogenome and virulence inventories of the stx+ strain, TT12A, isolated from a patient with hemorrhagic colitis, and its respective co-isolated stx- strain, TT12B. Sequencing the genomes to closure proved critical to the cataloguing of subtle strain differentiating sequence and structural polymorphisms at a high-level of phylogenetic accuracy and resolution. Phylogenomic profiling revealed SNP and MLST profiles similar to the near clonal outbreak isolates. Their prophage inventories, however, were notably different. The attenuated atypical non-shigatoxigenic status of TT12B is explained by the absence of both the ΦStx1a- and ΦStx2a-prophages carried by TT12A, and we also recorded further alterations in the non-Stx prophage complement. Phenotypic characterization indicated that culture growth was directly impacted by the strains' distinct lytic phage complement. Altogether, our phylogenomic and phenotypic analyses show that these intimately related isogenic strains are on divergent Stx(+/stx-) evolutionary paths.
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Affiliation(s)
- Anwar A. Kalalah
- Department of Molecular Microbiology and Immunology, University of Texas at San Antonio, San Antonio, TX 78249, USA
- South Texas Center for Emerging Infectious Diseases (STCEID), San Antonio, TX 78249, USA
| | - Sara S. K. Koenig
- Department of Molecular Microbiology and Immunology, University of Texas at San Antonio, San Antonio, TX 78249, USA
- South Texas Center for Emerging Infectious Diseases (STCEID), San Antonio, TX 78249, USA
| | - Peter Feng
- U.S. Food and Drug Administration (FDA), College Park, MD 20740, USA
| | - Joseph M. Bosilevac
- U.S. Department of Agriculture (USDA), Agricultural Research Service (ARS), U.S. Meat Animal Research Center, Clay Center, NE 68933, USA
| | - James L. Bono
- U.S. Department of Agriculture (USDA), Agricultural Research Service (ARS), U.S. Meat Animal Research Center, Clay Center, NE 68933, USA
| | - Mark Eppinger
- Department of Molecular Microbiology and Immunology, University of Texas at San Antonio, San Antonio, TX 78249, USA
- South Texas Center for Emerging Infectious Diseases (STCEID), San Antonio, TX 78249, USA
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Jeamsripong S, Thaotumpitak V, Anuntawirun S, Roongrojmongkhon N, Atwill ER, Hinthong W. Molecular Epidemiology of Antimicrobial Resistance and Virulence Profiles of Escherichia coli, Salmonella spp., and Vibrio spp. Isolated from Coastal Seawater for Aquaculture. Antibiotics (Basel) 2022; 11:antibiotics11121688. [PMID: 36551345 PMCID: PMC9774326 DOI: 10.3390/antibiotics11121688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 11/19/2022] [Accepted: 11/21/2022] [Indexed: 11/24/2022] Open
Abstract
The occurrence of waterborne antimicrobial-resistant (AMR) bacteria in areas of high-density oyster cultivation is an ongoing environmental and public health threat given the popularity of shellfish consumption, water-related human recreation throughout coastal Thailand, and the geographical expansion of Thailand's shellfish industry. This study characterized the association of phenotypic and genotypic AMR, including extended-spectrum β-lactamase (ESBL) production, and virulence genes isolated from waterborne Escherichia coli (E. coli) (n = 84), Salmonella enterica (S. enterica) subsp. enterica (n = 12), Vibrio parahaemolyticus (V. parahaemolyticus) (n = 249), and Vibrio cholerae (V. cholerae) (n = 39) from Thailand's coastal aquaculture regions. All Salmonella (100.0%) and half of V. cholerae (51.3%) isolates harbored their unique virulence gene, invA and ompW, respectively. The majority of isolates of V. parahaemolyticus and E. coli, ~25% of S. enterica subsp. enterica, and ~12% of V. cholerae, exhibited phenotypic AMR to multiple antimicrobials, with 8.9% of all coastal water isolates exhibiting multidrug resistance (MDR). Taken together, we recommend that coastal water quality surveillance programs include monitoring for bacterial AMR for food safety and recreational water exposure to water for Thailand's coastal water resources.
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Affiliation(s)
- Saharuetai Jeamsripong
- Research Unit in Microbial Food Safety and Antimicrobial Resistance, Department of Veterinary Public Health, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand
- Department of Veterinary Public Health, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand
- Correspondence: ; Tel.: +662-218-9579
| | - Varangkana Thaotumpitak
- Research Unit in Microbial Food Safety and Antimicrobial Resistance, Department of Veterinary Public Health, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand
- Department of Veterinary Public Health, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Saran Anuntawirun
- Department of Veterinary Public Health, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Nawaphorn Roongrojmongkhon
- Department of Veterinary Public Health, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Edward R. Atwill
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA
| | - Woranich Hinthong
- Princess Srisavangavadhana College of Medicine, Chulabhorn Royal Academy, Bangkok 10210, Thailand
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Ezzeroug Ezzraimi A, Hannachi N, Mariotti A, Rolain JM, Camoin-Jau L. Platelets and Escherichia coli: A Complex Interaction. Biomedicines 2022; 10:biomedicines10071636. [PMID: 35884941 PMCID: PMC9313189 DOI: 10.3390/biomedicines10071636] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 07/02/2022] [Accepted: 07/06/2022] [Indexed: 12/26/2022] Open
Abstract
Apart from their involvement in hemostasis, platelets have been recognized for their contribution to inflammation and defense against microbial agents. The interaction between platelets and bacteria has been well studied in the model of Staphylococcus and Streptococcus but little described in Gram-negative bacteria, especially Escherichia coli. Being involved in the hemolytic uremic syndrome as well as sepsis, it is important to study the mechanisms of interaction between platelets and E. coli. Results of the published studies are heterogeneous. It appears that some strains interact with platelets through the toll-like receptor-4 (TLR-4) and others through the Fc gamma glycoprotein. E. coli mainly uses lipopolysaccharide (LPS) to activate platelets and cause the release of antibacterial molecules, but this is not the case for all strains. In this review, we describe the different mechanisms developed in previous studies, focusing on this heterogeneity of responses that may depend on several factors; mainly, the strain studied, the structure of the LPS and the platelet form used in the studies. We can hypothesize that the structure of O-antigen and an eventual resistance to antibiotics might explain this difference.
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Affiliation(s)
- Amina Ezzeroug Ezzraimi
- IRD, APHM, MEPHI, IHU Méditerranée Infection, Aix Marseille Université, 19-21 Boulevard Jean Moulin, 13005 Marseille, France; (A.E.E.); (N.H.); (A.M.); (J.-M.R.)
- IHU Méditerranée Infection, Boulevard Jean Moulin, 13385 Marseille, France
| | - Nadji Hannachi
- IRD, APHM, MEPHI, IHU Méditerranée Infection, Aix Marseille Université, 19-21 Boulevard Jean Moulin, 13005 Marseille, France; (A.E.E.); (N.H.); (A.M.); (J.-M.R.)
- Département de Pharmacie, Faculté de Médecine, Université Ferhat Abbas Sétif I, Sétif 19000, Algeria
| | - Antoine Mariotti
- IRD, APHM, MEPHI, IHU Méditerranée Infection, Aix Marseille Université, 19-21 Boulevard Jean Moulin, 13005 Marseille, France; (A.E.E.); (N.H.); (A.M.); (J.-M.R.)
- IHU Méditerranée Infection, Boulevard Jean Moulin, 13385 Marseille, France
- Hematology Department, Timone Hospital, APHM, Boulevard Jean Moulin, 13005 Marseille, France
| | - Jean-Marc Rolain
- IRD, APHM, MEPHI, IHU Méditerranée Infection, Aix Marseille Université, 19-21 Boulevard Jean Moulin, 13005 Marseille, France; (A.E.E.); (N.H.); (A.M.); (J.-M.R.)
- IHU Méditerranée Infection, Boulevard Jean Moulin, 13385 Marseille, France
| | - Laurence Camoin-Jau
- IRD, APHM, MEPHI, IHU Méditerranée Infection, Aix Marseille Université, 19-21 Boulevard Jean Moulin, 13005 Marseille, France; (A.E.E.); (N.H.); (A.M.); (J.-M.R.)
- IHU Méditerranée Infection, Boulevard Jean Moulin, 13385 Marseille, France
- Hematology Department, Timone Hospital, APHM, Boulevard Jean Moulin, 13005 Marseille, France
- Correspondence: ; Tel.: +33-4-9138-6049; Fax: +33-4-9138-9155
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Tabaran A, Soulageon V, Chirila F, Reget OL, Mihaiu M, Borzan M, Dan SD. Pathogenic E. coli from Cattle as a Reservoir of Resistance Genes to Various Groups of Antibiotics. Antibiotics (Basel) 2022; 11:antibiotics11030404. [PMID: 35326867 PMCID: PMC8944818 DOI: 10.3390/antibiotics11030404] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 03/15/2022] [Accepted: 03/16/2022] [Indexed: 02/05/2023] Open
Abstract
Antimicrobial resistance has become a worldwide concern in all public health domains and reducing the spread has become a global priority. Pathogenic E. coli is responsible for a number of illnesses in humans and outbreaks in the past have been correlated with the consumption of contaminated bovine products. This is why surveillance in all the steps of production is essential. This study focused on identifying the pathogenic strains of E. coli in two large bovine abattoirs from Romania and France, and on associating them with the antimicrobial resistance patterns. A total of 250 samples from intestinal content were aseptically collected during the evisceration step of the cattle slaughtering process, from which 242 E. coli strains were isolated. Seventeen percent of all samples tested positive to at least one E. coli isolate carrying eaeA, stx1 and stx2 genes. The most prevalent genetic profile found in the E. coli strains tested was Stx1-positive and Stx2/eaeA-negative. More than 68% of the pathogenic E. coli isolated in Romania showed multi-drug resistance (MDR) and in France, the percentage was significantly lower (38%). The MDR profiles showed a high gene diversity for antibiotic resistance, which represents a great risk for environmental spread and human health. Our results indicate that in Romania, bovines can represent a reservoir for MDR E. coli and, hence, a surveillance system for antimicrobials usage in farm animals is highly needed.
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Affiliation(s)
- Alexandra Tabaran
- Animal Breeding and Food Safety Department, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine, Manastur Street No. 3/5, 400372 Cluj-Napoca, Romania; (V.S.); (O.L.R.); (M.M.); (M.B.); (S.D.D.)
- Correspondence:
| | - Virginie Soulageon
- Animal Breeding and Food Safety Department, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine, Manastur Street No. 3/5, 400372 Cluj-Napoca, Romania; (V.S.); (O.L.R.); (M.M.); (M.B.); (S.D.D.)
| | - Flore Chirila
- Microbiology Department, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine, Manastur Street No. 3/5, 400372 Cluj-Napoca, Romania;
| | - Oana Lucia Reget
- Animal Breeding and Food Safety Department, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine, Manastur Street No. 3/5, 400372 Cluj-Napoca, Romania; (V.S.); (O.L.R.); (M.M.); (M.B.); (S.D.D.)
| | - Marian Mihaiu
- Animal Breeding and Food Safety Department, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine, Manastur Street No. 3/5, 400372 Cluj-Napoca, Romania; (V.S.); (O.L.R.); (M.M.); (M.B.); (S.D.D.)
| | - Mihai Borzan
- Animal Breeding and Food Safety Department, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine, Manastur Street No. 3/5, 400372 Cluj-Napoca, Romania; (V.S.); (O.L.R.); (M.M.); (M.B.); (S.D.D.)
| | - Sorin Daniel Dan
- Animal Breeding and Food Safety Department, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine, Manastur Street No. 3/5, 400372 Cluj-Napoca, Romania; (V.S.); (O.L.R.); (M.M.); (M.B.); (S.D.D.)
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Moeinirad M, Douraghi M, Rahimi Foroushani A, Sanikhani R, Soltan Dallal MM. Molecular characterization and prevalence of virulence factor genes of Shiga toxin-producing Escherichia coli (STEC) isolated from diarrheic children. GENE REPORTS 2021. [DOI: 10.1016/j.genrep.2021.101379] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Elsayed MSAE, Eldsouky SM, Roshdy T, Bayoume AMA, Nasr GM, Salama ASA, Akl BA, Hasan AS, Shahat AK, Khashaba RA, Abdelhalim WA, Nasr HE, Mohammed LA, Salah A. Genetic and antimicrobial resistance profiles of non-O157 Shiga toxin-producing Escherichia coli from different sources in Egypt. BMC Microbiol 2021; 21:257. [PMID: 34556033 PMCID: PMC8461963 DOI: 10.1186/s12866-021-02308-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 08/28/2021] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND The Shiga toxin-producing Escherichia coli (STEC) represented a great risk to public health. In this study, 60 STEC strains recovered from broiler and duck fecal samples, cow's milk, cattle beef, human urine, and ear discharge were screened for 12 virulence genes, phenotypic and genotypic antimicrobial resistance, and multiple-locus variable-number tandem-repeat analysis (MLVA). RESULTS The majority of strains harbored Shiga toxin 1 (stx1) and stx1d, stx2 and stx2e, and ehxA genes, while a minority harbored stx2c subtype and eaeA. We identified 10 stx gene combinations; most of strains 31/60 (51.7%) exhibited four copies of stx genes, namely the stx1, stx1d, stx2, and stx2e, and the strains exhibited a high range of multiple antimicrobial resistance indices. The resistance genes blaCTX-M-1 and blaTEM were detected. For the oxytetracycline resistance genes, most of strains contained tetA, tetB, tetE, and tetG while the tetC was present at low frequency. MLVA genotyping resolved 26 unique genotypes; genotype 21 was highly prevalent. The six highly discriminatory loci DI = 0.9138 are suitable for the preliminary genotyping of STEC from animals and humans. CONCLUSIONS The STEC isolated from animals are virulent, resistant to antimicrobials, and genetically diverse, thus demands greater attention for the potential risk to human.
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Affiliation(s)
- Mohamed Sabry Abd Elraheam Elsayed
- Department of Bacteriology, Mycology, and Immunology, Faculty of Veterinary Medicine, University of Sadat City, Sadat City, Menoufia, Egypt.
| | - Samah Mahmoud Eldsouky
- Department of Otolaryngology and Head and Neck Surgery, Faculty of Medicine, Benha University, Benha, Egypt
| | - Tamer Roshdy
- Department of Molecular Biology, Genetic Engineering and Biotechnology Research Institute, University of Sadat City, Sadat City, Menoufia, Egypt
| | - Abeer Mohamed Ahmed Bayoume
- Department of Microbial Biotechnology, Genetic Engineering and Biotechnology Research Institute, University of Sadat City, Sadat City, Menoufia, Egypt
| | - Ghada M Nasr
- Department of Molecular Diagnostics, Genetic Engineering and Biotechnology Research Institute, University of Sadat City, Sadat City, Menoufia, 32897, Egypt
| | - Ali S A Salama
- Microbiology Department, Faculty of Agriculture, Zagazig University, Zagazig, Egypt
| | - Behiry A Akl
- Microbiology Department, Faculty of Agriculture, Zagazig University, Zagazig, Egypt
| | - Al Shaimaa Hasan
- Department of Medical Pharmacology, Qena Faculty of Medicine, South Valley University, Qena, Egypt
| | - Amany Kasem Shahat
- Department of Medical Microbiology and Immunology, Benha University, Benha, Egypt
| | - Rana Atef Khashaba
- Department of Clinical Pathology and Chemistry, Benha Faculty of Medicine, Benha University, Benha, Egypt
| | | | - Hend E Nasr
- Department of Medical Biochemistry and Molecular Biology, Benha University, Benha, Egypt
| | | | - Ahmed Salah
- Department of Molecular Biology, Genetic Engineering and Biotechnology Research Institute, University of Sadat City, Sadat City, Menoufia, Egypt
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Carroll KJ, Jenkins C, Harvey-Vince L, Mohan K, Balasegaram S. Shiga toxin-producing Escherichia coli diagnosed by Stx PCR: assessing the public health risk of non-O157 strains. Eur J Public Health 2021; 31:576-582. [PMID: 33411922 DOI: 10.1093/eurpub/ckaa232] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND The implementation by diagnostic laboratories in England of polymerase chain reaction (PCR) to screen faecal specimens for Shiga toxin-producing Escherichia coli (STEC) has resulted in a significant increase in notifications mainly due to non-O157 strains. The purpose of this study was to develop an approach to public health risk assessment that prioritizes follow-up to cases caused by haemolytic uraemic syndrome (HUS) associated E. coli (HUSEC) strains and minimizes unnecessary actions. METHODS Epidemiological and microbiological data were prospectively collected from 1 November 2013 to 31 March 2017 and used to compare three risk assessment approaches. RESULTS A history of HUS/bloody diarrhoea/age under 6 years and faecal specimens positive for stx-predicted HUSEC with a diagnostic accuracy of 84% (95% CI; 81-88%). STEC isolated by Gastrointestinal Bacteria Reference Unit (GBRU) and stx2 and eae positive predicted HUSEC with a diagnostic accuracy of 99% (95% CI; 98-100%). Risk assessment combining these two tests predicts the most efficient use of resources, predicting that 18% (97/552) of cases would be eligible for follow-up at some stage, 16% (86/552) following local stx PCR results, 1% (7/552) following GBRU results of stx2 and eae status and 0.7% (4/552) following whole-genome sequencing. Follow-up could be stopped in 78% (76/97) of these cases, 97% (74/76) following second stage risk assessment. CONCLUSIONS This three-stage risk assessment approach prioritizes follow-up to HUSEC and minimizes unnecessary public health actions. We developed it into the algorithm for public health actions included in the updated PHE Guidance for management of STEC published in August 2018.
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Affiliation(s)
- K J Carroll
- Surrey and Sussex Health Protection Team, Public Health England South East, Horsham, UK
| | - C Jenkins
- National Infection Service, Public Health England, London, UK
| | - L Harvey-Vince
- Surrey County Council Public Health Department, Kingston-Upon-Thames, UK
| | - K Mohan
- Thames Valley Health Protection Team, Public Health England South East, Chilton, UK
| | - S Balasegaram
- Field Service South East & London, Public Health England, London, UK
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Vachon MS, Khalid M, Tarr GAM, Hedberg C, Brown JA. Farm animal contact is associated with progression to Hemolytic uremic syndrome in patients with Shiga toxin-producing Escherichia coli - Indiana, 2012-2018. One Health 2020; 11:100175. [PMID: 33392374 PMCID: PMC7772627 DOI: 10.1016/j.onehlt.2020.100175] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 09/23/2020] [Accepted: 09/23/2020] [Indexed: 11/30/2022] Open
Abstract
Background Hemolytic uremic syndrome (HUS) is a life-threatening complication of Shiga toxin-producing Escherichia coli (STEC) infection. The relationship between STEC exposure and severity of clinical outcomes is not well documented. We examined whether direct contact with farm animals increased the likelihood of HUS among Indiana residents diagnosed with STEC. Methods Exposure data for laboratory-confirmed STEC cases among Indiana residents during 2012–2018 were retrieved. Logistic regression and mediation analysis were performed to determine the extent to which a history of direct contact with farm animals was associated with post-diarrheal HUS independent of age and mediated by stx2 gene presence. Results A total of 784 STEC cases were retrieved. Of these, 46 (6%) developed HUS. Complete exposure data were available for 600 (77%) cases. A total of 24 (52%) HUS patients reported direct contact with farm animals, while 114 (21%) STEC patients who did not develop HUS reported this exposure. Among all STEC cases, HUS was associated with direct farm animal contact after adjusting for age (OR = 3.40, 95% CI: 1.81, 6.40). Detection of stx2 genes mediated 12% of the association between farm animal contact and HUS. Conclusions Direct farm animal contact was a risk factor for development of HUS among laboratory-confirmed STEC cases, independent of stx2 presence. Direct farm animal contact should be considered a potential predictor of progression to HUS when patients present for care and the mechanism for its effect on virulence investigated. Independent of stx2 presence, contact with farm animals is a risk factor for the development of HUS. Stx2 gene detection mediated 12.2% of the association between farm animal contact and HUS. Exposure source may impact virulence of STEC and thus the severity of clinical outcomes.
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Affiliation(s)
- Madhura S Vachon
- Division of Environmental Health Sciences, University of Minnesota School of Public Health, 420 Delaware St. SE, Minneapolis, MN, USA, 55455
| | - Myda Khalid
- Department of Pediatric Nephrology and Kidney Diseases, Riley Hospital for Children 575 Riley Hospital Dr., Indianapolis, IN, USA, 46202
| | - Gillian A M Tarr
- Division of Environmental Health Sciences, University of Minnesota School of Public Health, 420 Delaware St. SE, Minneapolis, MN, USA, 55455
| | - Craig Hedberg
- Division of Environmental Health Sciences, University of Minnesota School of Public Health, 420 Delaware St. SE, Minneapolis, MN, USA, 55455
| | - Jennifer A Brown
- Epidemiology Resource Center, Indiana State Department of Health, 2 N. Meridian St. Indianapolis, IN, USA, 46204
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11
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A Toxic Environment: a Growing Understanding of How Microbial Communities Affect Escherichia coli O157:H7 Shiga Toxin Expression. Appl Environ Microbiol 2020; 86:AEM.00509-20. [PMID: 32358004 DOI: 10.1128/aem.00509-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Enterohemorrhagic Escherichia coli (EHEC) strains, including E. coli O157:H7, cause severe illness in humans due to the production of Shiga toxin (Stx) and other virulence factors. Because Stx is coregulated with lambdoid prophage induction, its expression is especially susceptible to environmental cues. Infections with Stx-producing E. coli can be difficult to model due to the wide range of disease outcomes: some infections are relatively mild, while others have serious complications. Probiotic organisms, members of the gut microbiome, and organic acids can depress Stx production, in many cases by inhibiting the growth of EHEC strains. On the other hand, the factors currently known to amplify Stx act via their effect on the stx-converting phage. Here, we characterize two interactive mechanisms that increase Stx production by O157:H7 strains: first, direct interactions with phage-susceptible E. coli, and second, indirect amplification by secreted factors. Infection of susceptible strains by the stx-converting phage can expand the Stx-producing population in a human or animal host, and phage infection has been shown to modulate virulence in vitro and in vivo Acellular factors, particularly colicins and microcins, can kill O157:H7 cells but may also trigger Stx expression in the process. Colicins, microcins, and other bacteriocins have diverse cellular targets, and many such molecules remain uncharacterized. The identification of additional Stx-amplifying microbial interactions will improve our understanding of E. coli O157:H7 infections and help elucidate the intricate regulation of pathogenicity in EHEC strains.
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12
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Nyong EC, Zaia SR, Allué-Guardia A, Rodriguez AL, Irion-Byrd Z, Koenig SSK, Feng P, Bono JL, Eppinger M. Pathogenomes of Atypical Non-shigatoxigenic Escherichia coli NSF/SF O157:H7/NM: Comprehensive Phylogenomic Analysis Using Closed Genomes. Front Microbiol 2020; 11:619. [PMID: 32351476 PMCID: PMC7175801 DOI: 10.3389/fmicb.2020.00619] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 03/19/2020] [Indexed: 12/19/2022] Open
Abstract
The toxigenic conversion of Escherichia coli strains by Shiga toxin-converting (Stx) bacteriophages were prominent and recurring events in the stepwise evolution of enterohemorrhagic E. coli (EHEC) O157:H7 from an enteropathogenic (EPEC) O55:H7 ancestor. Atypical, attenuated isolates have been described for both non-sorbitol fermenting (NSF) O157:H7 and SF O157:NM serotypes, which are distinguished by the absence of Stx, the characteristic virulence hallmark of Stx-producing E. coli (STEC). Such atypical isolates either never acquired Stx-phages or may have secondarily lost stx during the course of infection, isolation, or routine subculture; the latter are commonly referred to as LST (Lost Shiga Toxin)-isolates. In this study we analyzed the genomes of 15 NSF O157:H7 and SF O157:NM strains from North America, Europe, and Asia that are characterized by the absence of stx, the virulence hallmark of STEC. The individual genomic basis of the Stx (-) phenotype has remained largely undetermined as the majority of STEC genomes in public genome repositories were generated using short read technology and are in draft stage, posing a major obstacle for the high-resolution whole genome sequence typing (WGST). The application of LRT (long-read technology) sequencing provided us with closed genomes, which proved critical to put the atypical non-shigatoxigenic NSF O157:H7 and SF O157:NM strains into the phylogenomic context of the stepwise evolutionary model. Availability of closed chromosomes for representative Stx (-) NSF O157:H7 and SF O157:NM strains allowed to describe the genomic basis and individual evolutionary trajectories underlying the absence of Stx at high accuracy and resolution. The ability of LRT to recover and accurately assemble plasmids revealed a strong correlation between the strains' featured plasmid genotype and chromosomally inferred clade, which suggests the coevolution of the chromosome and accessory plasmids. The identified ancestral traits in the pSFO157 plasmid of NSF O157:H7 strain LSU-61 provided additional evidence for its intermediate status. Taken together, these observations highlight the utility of LRTs for advancing our understanding of EHEC O157:H7/NM pathogenome evolution. Insights into the genomic and phenotypic plasticity of STEC on a lineage- and genome-wide scale are foundational to improve and inform risk assessment, biosurveillance, and prevention strategies.
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Affiliation(s)
- Emmanuel C. Nyong
- Department of Biology, The University of Texas at San Antonio, San Antonio, TX, United States
- South Texas Center for Emerging Infectious Diseases, San Antonio, TX, United States
| | - Sam R. Zaia
- Department of Biology, The University of Texas at San Antonio, San Antonio, TX, United States
- South Texas Center for Emerging Infectious Diseases, San Antonio, TX, United States
| | - Anna Allué-Guardia
- Department of Biology, The University of Texas at San Antonio, San Antonio, TX, United States
- South Texas Center for Emerging Infectious Diseases, San Antonio, TX, United States
| | - Armando L. Rodriguez
- Research Computing Support Group, The University of Texas at San Antonio, San Antonio, TX, United States
| | - Zaina Irion-Byrd
- Department of Biology, The University of Texas at San Antonio, San Antonio, TX, United States
- South Texas Center for Emerging Infectious Diseases, San Antonio, TX, United States
| | - Sara S. K. Koenig
- Department of Biology, The University of Texas at San Antonio, San Antonio, TX, United States
- South Texas Center for Emerging Infectious Diseases, San Antonio, TX, United States
| | | | - James L. Bono
- United States Meat Animal Research Center, Agricultural Research Service, United States Department of Agriculture (ARS-USDA), Clay Center, NE, United States
| | - Mark Eppinger
- Department of Biology, The University of Texas at San Antonio, San Antonio, TX, United States
- South Texas Center for Emerging Infectious Diseases, San Antonio, TX, United States
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13
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Hauser JR, Atitkar RR, Petro CD, Lindsey RL, Strockbine N, O'Brien AD, Melton-Celsa AR. The Virulence of Escherichia coli O157:H7 Isolates in Mice Depends on Shiga Toxin Type 2a (Stx2a)-Induction and High Levels of Stx2a in Stool. Front Cell Infect Microbiol 2020; 10:62. [PMID: 32175286 PMCID: PMC7054288 DOI: 10.3389/fcimb.2020.00062] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 02/07/2020] [Indexed: 12/28/2022] Open
Abstract
In this study we compared nine Shiga toxin (Stx)-producing Escherichia coli O157:H7 patient isolates for Stx levels, stx-phage insertion site(s), and pathogenicity in a streptomycin (Str)-treated mouse model. The strains encoded stx2a, stx1a and stx2a, or stx2a and stx2c. All of the strains elaborated 105-106 cytotoxic doses 50% (CD50) into the supernatant after growth in vitro as measured on Vero cells, and showed variable levels of increased toxin production after growth with sub-inhibitory levels of ciprofloxacin (Cip). The stx2a+stx2c+ isolates were 90–100% lethal for Str-treated BALB/c mice, though one isolate, JH2013, had a delayed time-to-death. The stx2a+ isolate was avirulent. Both an stx2a and a recA deletion mutant of one of the stx2a+stx2c+ strains, JH2010, exhibited at least a three-log decrease in cytotoxicity in vitro and both were avirulent in the mice. Stool from Str-treated mice infected with the highly virulent isolates were 10- to 100-fold more cytotoxic than feces from mice infected with the clinical isolate, JH2012, that made only Stx2a. Taken together these findings demonstrate that the stx2a-phage from JH2010 induces to higher levels in vivo than does the phage from JH2012. The stx1a+stx2a+ clinical isolates were avirulent and neutralization of Stx1 in stool from mice infected with those strains indicated that the toxin produced in vivo was primarily Stx1a. Treatment of mice infected with Stx1a+Stx2a+ isolates with Cip resulted in an increase in Stx2a production in vivo and lethality in the mice. Our data suggest that high levels of Stx2a in stool are predictive of virulence in mice.
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Affiliation(s)
- Jocelyn R Hauser
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Rama R Atitkar
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Courtney D Petro
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Rebecca L Lindsey
- Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - Nancy Strockbine
- Centers for Disease Control and Prevention, Atlanta, GA, United States
| | - Alison D O'Brien
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | - Angela R Melton-Celsa
- Department of Microbiology and Immunology, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
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14
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Tarr GAM, Stokowski T, Shringi S, Tarr PI, Freedman SB, Oltean HN, Rabinowitz PM, Chui L. Contribution and Interaction of Shiga Toxin Genes to Escherichia coli O157:H7 Virulence. Toxins (Basel) 2019; 11:toxins11100607. [PMID: 31635282 PMCID: PMC6832461 DOI: 10.3390/toxins11100607] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 10/14/2019] [Accepted: 10/16/2019] [Indexed: 01/17/2023] Open
Abstract
Escherichia coli O157:H7 is the predominant cause of diarrhea-associated hemolytic uremic syndrome (HUS) worldwide. Its cardinal virulence traits are Shiga toxins, which are encoded by stx genes, the most common of which are stx1a, stx2a, and stx2c. The toxins these genes encode differ in their in vitro and experimental phenotypes, but the human population-level impact of these differences is poorly understood. Using Shiga toxin-encoding bacteriophage insertion typing and real-time polymerase chain reaction, we genotyped isolates from 936 E. coli O157:H7 cases and verified HUS status via chart review. We compared the HUS risk between isolates with stx2a and those with stx2a and another gene and estimated additive interaction of the stx genes. Adjusted for age and symptoms, the HUS incidence of E. coli O157:H7 containing stx2a alone was 4.4% greater (95% confidence interval (CI) −0.3%, 9.1%) than when it occurred with stx1a. When stx1a and stx2a occur together, the risk of HUS was 27.1% lower (95% CI −87.8%, −2.3%) than would be expected if interaction were not present. At the population level, temporal or geographic shifts toward these genotypes should be monitored, and stx genotype may be an important consideration in clinically predicting HUS among E. coli O157:H7 cases.
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Affiliation(s)
- Gillian A M Tarr
- Department of Pediatrics, Cumming School of Medicine, University of Calgary, Calgary, AB T3B 6A8, Canada.
| | - Taryn Stokowski
- Department of Laboratory Medicine and Pathology, University of Alberta and Alberta Public Labs, Edmonton, AB T6G 2J2, Canada.
| | - Smriti Shringi
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99163, USA.
| | - Phillip I Tarr
- Division of Gastroenterology, Hepatology, and Nutrition, Washington University School of Medicine, St. Louis, MO 63110, USA.
| | - Stephen B Freedman
- Department of Pediatrics, Cumming School of Medicine, University of Calgary, Calgary, AB T3B 6A8, Canada.
| | - Hanna N Oltean
- Washington State Department of Health, Shoreline, WA 98155, USA.
| | - Peter M Rabinowitz
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA 98195, USA.
| | - Linda Chui
- Department of Laboratory Medicine and Pathology, University of Alberta and Alberta Public Labs, Edmonton, AB T6G 2J2, Canada.
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15
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Liu Y, Liu B, Yang P, Wang T, Chang Z, Wang J, Wang Q, Li W, Wu J, Huang D, Jiang L, Yang B. LysR-type transcriptional regulator OvrB encoded in O island 9 drives enterohemorrhagic Escherichia coli O157:H7 virulence. Virulence 2019; 10:783-792. [PMID: 31502495 PMCID: PMC6768210 DOI: 10.1080/21505594.2019.1661721] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Enterohemorrhagic Escherichia coli (EHEC) O157:H7 (O157) is a major foodborne pathogen that causes severe illness in humans worldwide. The genome of O157 contains 177 genomic islands known as O islands (OIs), including Shiga toxin-converting phages (OI-45 and OI-93) and the locus for enterocyte effacement (LEE) pathogenicity island (OI-148). However, most genes in OIs are uncharacterized and code for unknown functions. In this study, we demonstrated, for the first time, that OI-9 encodes a novel transcriptional activator, Z0346 (named OvrB), which is required for bacterial adherence to host cells and LEE gene expression in O157. OvrB directly binds to the promoter region of LEE1 and activates the transcription of ler (encoding a master regulator of LEE genes), which in turn activates LEE1–5 genes to promote O157 adherence. Furthermore, mouse oral infection assays showed that OvrB promotes O157 colonization in the mouse intestine. Finally, OvrB is shown to be a widespread transcriptional activator of virulence genes in other enterohemorrhagic and enteropathogenic Escherichia coli serotypes. Our work significantly expands the understanding of bacterial virulence control and provides new evidence suggesting that horizontally transferred regulator genes mediate LEE gene expression.
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Affiliation(s)
- Yutao Liu
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA , Tianjin , P. R. China.,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education , Tianjin , P. R. China
| | - Bin Liu
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA , Tianjin , P. R. China.,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education , Tianjin , P. R. China
| | - Pan Yang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA , Tianjin , P. R. China.,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education , Tianjin , P. R. China
| | - Ting Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA , Tianjin , P. R. China.,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education , Tianjin , P. R. China
| | - Zhanhe Chang
- School of Biomedical Engineering, Tianjin Medical University , Tianjin , P. R. China
| | - Junyue Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA , Tianjin , P. R. China.,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education , Tianjin , P. R. China
| | - Qian Wang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA , Tianjin , P. R. China.,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education , Tianjin , P. R. China
| | - Wendi Li
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA , Tianjin , P. R. China.,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education , Tianjin , P. R. China
| | - Jialin Wu
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA , Tianjin , P. R. China.,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education , Tianjin , P. R. China
| | - Di Huang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA , Tianjin , P. R. China.,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education , Tianjin , P. R. China
| | - Lingyan Jiang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA , Tianjin , P. R. China.,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education , Tianjin , P. R. China
| | - Bin Yang
- TEDA Institute of Biological Sciences and Biotechnology, Nankai University, TEDA , Tianjin , P. R. China.,The Key Laboratory of Molecular Microbiology and Technology, Ministry of Education , Tianjin , P. R. China
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16
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The importance of integrating genetic strain information for managing cases of Shiga toxin-producing E. coli infection. Epidemiol Infect 2019; 147:e264. [PMID: 31496452 PMCID: PMC6805796 DOI: 10.1017/s0950268819001602] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
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17
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Shiga toxin-producing Escherichia coli in British Columbia, 2011-2017: Analysis to inform exclusion guidelines. ACTA ACUST UNITED AC 2019; 45:238-243. [PMID: 31556405 DOI: 10.14745/ccdr.v45i09a03] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Background Shiga toxin-producing Escherichia coli (STEC) can cause severe illness including bloody diarrhea and hemolytic-uremic syndrome (HUS) through the production of Shiga toxins 1 (Stx1) and 2 (Stx2). E. coli O157:H7 was the most common serotype detected in the 1980s to 1990s, but improvements in laboratory methods have led to increased detection of non-O157 STEC. Non-O157 STEC producing only Stx1 tend to cause milder clinical illness. Exclusion guidelines restrict return to high-risk work or settings for STEC cases, but most do not differentiate between STEC serogroups and Stx type. Objective To analyze British Columbia (BC) laboratory and surveillance data to inform the BC STEC exclusion guideline. Methods For all STEC cases reported in BC in 2011-2017, laboratory and epidemiological data were obtained through provincial laboratory and reportable disease electronic systems, respectively. Incidence was measured for all STEC combined as well as by serogroup. Associations were measured between serogroups, Stx types and clinical outcomes. Results Over the seven year period, 984 cases of STEC were reported. A decrease in O157 incidence was observed, while non-O157 rates increased. The O157 serogroup was significantly associated with Stx2. Significant associations were observed between Stx2 and bloody diarrhea, hospitalization and HUS. Conclusion The epidemiology of STEC has changed in BC as laboratories increasingly distinguish between O157 and non-O157 cases and identify Stx type. It appears that non-O157 cases with Stx1 are less severe than O157 cases with Stx2. The BC STEC exclusion guidelines were updated as a result of this analysis.
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18
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Shimizu T, Matsumoto A, Noda M. Cooperative Roles of Nitric Oxide-Metabolizing Enzymes To Counteract Nitrosative Stress in Enterohemorrhagic Escherichia coli. Infect Immun 2019; 87:e00334-19. [PMID: 31209149 PMCID: PMC6704613 DOI: 10.1128/iai.00334-19] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Accepted: 06/08/2019] [Indexed: 11/20/2022] Open
Abstract
Enterohemorrhagic Escherichia coli (EHEC) has at least three enzymes, NorV, Hmp, and Hcp, that act independently to lower the toxicity of nitric oxide (NO), a potent antimicrobial molecule. This study aimed to reveal the cooperative roles of these defensive enzymes in EHEC against nitrosative stress. Under anaerobic conditions, combined deletion of all three enzymes significantly increased the NO sensitivity of EHEC determined by the growth at late stationary phase; however, the expression of norV restored the NO resistance of EHEC. On the other hand, the growth of Δhmp mutant EHEC was inhibited after early stationary phase, indicating that NorV and Hmp play a cooperative role in anaerobic growth. Under microaerobic conditions, the growth of Δhmp mutant EHEC was inhibited by NO, indicating that Hmp is the enzyme that protects cells from NO stress under microaerobic conditions. When EHEC cells were exposed to a lower concentration of NO, the NO level in bacterial cells of Δhcp mutant EHEC was higher than those of the other EHEC mutants, suggesting that Hcp is effective at regulating NO levels only at a low concentration. These findings of a low level of NO in bacterial cells with hcp indicate that the NO consumption activity of Hcp was suppressed by Hmp at a low range of NO concentrations. Taken together, these results show that the cooperative effects of NO-metabolizing enzymes are regulated by the range of NO concentrations to which the EHEC cells are exposed.
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Affiliation(s)
- Takeshi Shimizu
- Department of Molecular Infectiology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Akio Matsumoto
- Department of Aging Pharmacology, School of Medicine, Toho University, Tokyo, Japan
| | - Masatoshi Noda
- Department of Molecular Infectiology, Graduate School of Medicine, Chiba University, Chiba, Japan
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19
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Karama M, Mainga AO, Cenci-Goga BT, Malahlela M, El-Ashram S, Kalake A. Molecular profiling and antimicrobial resistance of Shiga toxin-producing Escherichia coli O26, O45, O103, O121, O145 and O157 isolates from cattle on cow-calf operations in South Africa. Sci Rep 2019; 9:11930. [PMID: 31417098 PMCID: PMC6695430 DOI: 10.1038/s41598-019-47948-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 07/26/2019] [Indexed: 01/16/2023] Open
Abstract
In this study, 140 cattle STEC isolates belonging to serogroups O157, O26, O145, O121, O103 and O45 were characterized for 38 virulence-associated genes, antimicrobial resistance profiles and genotyped by PFGE. The majority of isolates carried both stx1 and stx2 concurrently, stx2c, and stx2d; plasmid-encoded genes ehxA, espP, subA and saa but lacked katP and etpD and eaeA. Possession of eaeA was significantly associated with the presence of nle genes, katP, etpD, ureC and terC. However, saa and subA, stx1c and stx1d were only detected in eaeA negative isolates. A complete OI-122 and most non-LEE effector genes were detected in only two eaeA positive serotypes, including STEC O157:H7 and O103:H2. The eaeA gene was detected in STEC serotypes that are commonly implicated in severe humans disease and outbreaks including STEC O157:H7, STEC O145:H28 and O103:H2. PFGE revealed that the isolates were highly diverse with very low rates of antimicrobial resistance. In conclusion, only a small number of cattle STEC serotypes that possessed eaeA, had the highest number of virulence-associated genes, indicative of their high virulence. Further characterization of STEC O157:H7, STEC O145:H28 and O103:H2 using whole genome sequencing will be needed to fully understand their virulence potential for humans.
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Affiliation(s)
- Musafiri Karama
- Veterinary Public Health Section, Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa.
| | - Alfred O Mainga
- Veterinary Public Health Section, Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
| | - Beniamino T Cenci-Goga
- Veterinary Public Health Section, Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa.,Dipartimento di Scienze Biopatologiche, Laboratorio di Ispezione degli Alimenti di Origine Animale, Facoltà di Medicina Veterinaria, Università degli Studi di Perugia, Perugia, Italy
| | - Mogaugedi Malahlela
- Veterinary Public Health Section, Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
| | - Saeed El-Ashram
- School of Life Science and Engineering, Foshan University, Foshan, China.,Faculty of Science, Kafrelsheikh University, Kafr El-Sheikh, Egypt
| | - Alan Kalake
- Gauteng Department of Agriculture and Rural Development (GDARD), Johannesburg, South Africa
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20
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Carroll KJ, Harvey-Vince L, Jenkins C, Mohan K, Balasegaram S. The epidemiology of Shiga toxin-producing Escherichia coli infections in the South East of England: November 2013-March 2017 and significance for clinical and public health. J Med Microbiol 2019; 68:930-939. [PMID: 30994441 DOI: 10.1099/jmm.0.000970] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
PURPOSE This study describes the epidemiology of Shiga toxin-producing Escherichia coli (STEC) infections in a population in the South East of England. METHODS From 1 November 2013 to 31 March 2017 participating diagnostic laboratories reported Shiga toxin gene (stx) positive real-time PCR results to local public health teams. Stx positive faecal samples/isolates were referred to the Gastrointestinal Bacteria Reference Unit (GBRU) for confirmation by culture and typing by whole genome sequencing (WGS). Key clinical information was collected by public health teams.Results/Key findings. Altogether, 548 faecal specimens (420 were non-travel associated) were stx positive locally, 535 were submitted to the GBRU. STEC were isolated from 42 %, confirmed by stx PCR in 21 % and 37 % were PCR negative. The most common non-travel associated STEC serogroups were O157, O26, O146 and O91. The annualized incidence of confirmed STEC infections (PCR or culture) was 5.8 per 100 000. The ratio of O157 to non-O157 STEC serogroups was 1:7. The annualized incidence of non-O157 haemolytic uraemic syndrome-associated Escherichia coli (HUSEC) strains was 0.4 per 100 000. Bloody diarrhoea was reported by 58 % of cases infected with E. coli O157, 33 % of cases infected with non-O157 HUSEC strains and 12 % of other lower risk non-O157 strains. Overall, 76 % of non-O157 HUSEC isolates possessed the eae virulence gene. CONCLUSIONS HUSEC including serogroup O157 were uncommon and more likely to cause bloody diarrhoea than other STEC. The routine use of stx PCR testing can influence clinical management. Understanding the local epidemiology facilitates a proportionate public health response to STEC, based on clinical and microbiological characteristics including stx subtype(s).
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Affiliation(s)
- Kevin J Carroll
- 1 PHE South East, Surrey and Sussex HPT, Parkside, Chart Way, Horsham RH12 1XA, UK
| | - Lisa Harvey-Vince
- 1 PHE South East, Surrey and Sussex HPT, Parkside, Chart Way, Horsham RH12 1XA, UK
| | - Claire Jenkins
- 2 Gastrointestinal Bacteria Reference Unit, Public Health England, 61 Colindale Avenue, London NW9 5HT, UK
| | - Keerthi Mohan
- 3 PHE South East, Thames Valley HPT, Chilton, Oxon, OX11 0RQ, UK
| | - Sooria Balasegaram
- 4 Field Services, National Infection Service, Public Health England, London, UK
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Varcasia BM, Tomassetti F, De Santis L, Di Giamberardino F, Lovari S, Bilei S, De Santis P. Presence of Shiga Toxin-Producing Escherichia coli (STEC) in Fresh Beef Marketed in 13 Regions of ITALY (2017). Microorganisms 2018; 6:E126. [PMID: 30563244 PMCID: PMC6313577 DOI: 10.3390/microorganisms6040126] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 11/30/2018] [Accepted: 12/05/2018] [Indexed: 01/02/2023] Open
Abstract
The aim of this study was to determine the prevalence of Shiga toxin-producing Escherichia coli in fresh beef marketed in 2017 in 13 regions of Italy, to evaluate the potential risk to human health. According to the ISO/TS 13136:2012 standard, 239 samples were analysed and nine were STEC positive, from which 20 strains were isolated. The STEC-positive samples were obtained from Calabria (n = 1), Campania (n = 1), Lazio (n = 2), Liguria (n = 1), Lombardia (n = 1) and Veneto (n = 3). All STEC strains were analysed for serogroups O26, O45, O55, O91, O103, O104, O111, O113, O121, O128, O145, O146 and O157, using Real-Time PCR. Three serogroups were identified amongst the 20 strains: O91 (n = 5), O113 (n = 2), and O157 (n = 1); the O-group for each of the 12 remaining STEC strains was not identified. Six stx subtypes were detected: stx1a, stx1c, stx2a, stx2b, stx2c and stx2d. Subtype stx2c was the most common, followed by stx2d and stx2b. Subtype stx2a was identified in only one eae-negative strain and occurred in combination with stx1a, stx1c and stx2b. The presence in meat of STEC strains being potentially harmful to human health shows the importance, during harvest, of implementing additional measures to reduce contamination risk.
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Affiliation(s)
- Bianca Maria Varcasia
- Istituto Zooprofilattico Sperimentale Lazio e Toscana, "M. Aleandri", 00178 Rome, Italy.
| | - Francesco Tomassetti
- Istituto Zooprofilattico Sperimentale Lazio e Toscana, "M. Aleandri", 00178 Rome, Italy.
| | - Laura De Santis
- Istituto Zooprofilattico Sperimentale Lazio e Toscana, "M. Aleandri", 00178 Rome, Italy.
| | | | - Sarah Lovari
- Istituto Zooprofilattico Sperimentale Lazio e Toscana, "M. Aleandri", 00178 Rome, Italy.
| | - Stefano Bilei
- Istituto Zooprofilattico Sperimentale Lazio e Toscana, "M. Aleandri", 00178 Rome, Italy.
| | - Paola De Santis
- Istituto Zooprofilattico Sperimentale Lazio e Toscana, "M. Aleandri", 00178 Rome, Italy.
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Importance of case age in the purported association between phylogenetics and hemolytic uremic syndrome in Escherichia coli O157:H7 infections. Epidemiol Infect 2018; 146:1550-1555. [PMID: 29914582 DOI: 10.1017/s0950268818001632] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Escherichia coli O157:H7 is the largest cause of hemolytic uremic syndrome (HUS). Previous studies proposed that HUS risk varies across the E. coli O157:H7 phylogenetic tree (hypervirulent clade 8), but the role of age in the association is unknown. We determined phylogenetic lineage of E. coli O157:H7 isolates from 1160 culture-confirmed E. coli O157:H7 cases reported in Washington State, 2004-2015. Using generalised estimating equations, we tested the association between phylogenetic lineage and HUS. Age was evaluated as an effect modifier. Among 1082 E. coli O157:H7 cases with both phylogenetic lineage and HUS status (HUS n = 76), stratified analysis suggested effect modification by age. Lineages IIa and IIb, relative to Ib, did not appear associated with HUS in children 0-9-years-old. For cases 10-59-years-old, lineages IIa and IIb appeared to confer increased risk of HUS, relative to lineage Ib. The association reversed in ⩾60-year-olds. Results were similar for clade 8. Phylogenetic lineage appears to be associated with HUS risk only among those ⩾10-years-old. Among children <10, the age group most frequently affected, lineage does not explain progression to HUS. However, lineage frequency varied across age groups, suggesting differences in exposure and/or early disease manifestation.
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Krause M, Barth H, Schmidt H. Toxins of Locus of Enterocyte Effacement-Negative Shiga Toxin-Producing Escherichia coli. Toxins (Basel) 2018; 10:toxins10060241. [PMID: 29903982 PMCID: PMC6024878 DOI: 10.3390/toxins10060241] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 06/07/2018] [Accepted: 06/12/2018] [Indexed: 12/16/2022] Open
Abstract
Studies on Shiga toxin-producing Escherichia coli (STEC) typically examine and classify the virulence gene profiles based on genomic analyses. Among the screened strains, a subgroup of STEC which lacks the locus of enterocyte effacement (LEE) has frequently been identified. This raises the question about the level of pathogenicity of such strains. This review focuses on the advantages and disadvantages of the standard screening procedures in virulence profiling and summarizes the current knowledge concerning the function and regulation of toxins encoded by LEE-negative STEC. Although LEE-negative STEC usually come across as food isolates, which rarely cause infections in humans, some serotypes have been implicated in human diseases. In particular, the LEE-negative E. coli O104:H7 German outbreak strain from 2011 and the Australian O113:H21 strain isolated from a HUS patient attracted attention. Moreover, the LEE-negative STEC O113:H21 strain TS18/08 that was isolated from minced meat is remarkable in that it not only encodes multiple toxins, but in fact expresses three different toxins simultaneously. Their characterization contributes to understanding the virulence of the LEE-negative STEC.
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Affiliation(s)
- Maike Krause
- Department of Food Microbiology and Hygiene, Institute of Food Science and Biotechnology, Garbenstrasse 28, University of Hohenheim, 70599 Stuttgart, Germany.
| | - Holger Barth
- Institute of Pharmacology and Toxicology, University of Ulm Medical Center, Albert-Einstein-Allee 11, 89081 Ulm, Germany.
| | - Herbert Schmidt
- Department of Food Microbiology and Hygiene, Institute of Food Science and Biotechnology, Garbenstrasse 28, University of Hohenheim, 70599 Stuttgart, Germany.
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Bury S, Soundararajan M, Bharti R, von Bünau R, Förstner KU, Oelschlaeger TA. The Probiotic Escherichia coli Strain Nissle 1917 Combats Lambdoid Bacteriophages stx and λ. Front Microbiol 2018; 9:929. [PMID: 29896160 PMCID: PMC5987069 DOI: 10.3389/fmicb.2018.00929] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 04/20/2018] [Indexed: 01/21/2023] Open
Abstract
Shiga toxin (Stx) producing E. coli (STEC) such as Enterohemorrhagic E. coli (EHEC) are the major cause of foodborne illness in humans. In vitro studies showed the probiotic Escherichia coli strain Nissle 1917 (EcN) to efficiently inhibit the production of Stx. Life threatening EHEC strains as for example the serotype O104:H4, responsible for the great outbreak in 2011 in Germany, evolutionary developed from certain E. coli strains which got infected by stx2-encoding lambdoid phages turning the E. coli into lysogenic and subsequently Stx producing strains. Since antibiotics induce stx genes and Stx production, EHEC infected persons are not recommended to be treated with antibiotics. Therefore, EcN might be an alternative medication. However, because even commensal E. coli strains might be converted into Stx-producers after becoming host to a stx encoding prophage, we tested EcN for stx-phage genome integration. Our experiments revealed the resistance of EcN toward not only stx-phages but also against lambda-phages. This resistance was not based on the lack of or by mutated phage receptors. Rather it involved the expression of a phage repressor (pr) gene of a defective prophage in EcN which was able to partially protect E. coli K-12 strain MG1655 against stx and lambda phage infection. Furthermore, we observed EcN to inactivate phages and thereby to protect E. coli K-12 strains against infection by stx- as well as lambda-phages. Inactivation of lambda-phages was due to binding of lambda-phages to LamB of EcN whereas inactivation of stx-phages was caused by a thermostable protein of EcN. These properties together with its ability to inhibit Stx production make EcN a good candidate for the prevention of illness caused by EHEC and probably for the treatment of already infected people.
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Affiliation(s)
- Susanne Bury
- Institute for Molecular Infection Biology, University of Würzburg, Würzburg, Germany
| | | | - Richa Bharti
- Institute for Molecular Infection Biology, University of Würzburg, Würzburg, Germany
| | | | - Konrad U Förstner
- Institute for Molecular Infection Biology, University of Würzburg, Würzburg, Germany
| | - Tobias A Oelschlaeger
- Institute for Molecular Infection Biology, University of Würzburg, Würzburg, Germany
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Thuraisamy T, Lodato PB. Influence of RNase E deficiency on the production of stx2-bearing phages and Shiga toxin in an RNase E-inducible strain of enterohaemorrhagic Escherichia coli (EHEC) O157:H7. J Med Microbiol 2018; 67:724-732. [PMID: 29620505 PMCID: PMC7001489 DOI: 10.1099/jmm.0.000728] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 03/21/2018] [Indexed: 12/14/2022] Open
Abstract
PURPOSE In enterohaemorrhagic Escherichia coli (EHEC), stx1 or stx2 genes encode Shiga toxin (Stx1 or Stx2, respectively) and are carried by prophages. The production and release of both stx phages and toxin occur upon initiation of the phage lytic cycle. Phages can further disseminate stx genes by infecting naïve bacteria in the intestine. Here, the effect of RNase E deficiency on these two virulence traits was investigated. METHODOLOGY Cultures of the EHEC strains TEA028-rne containing low versus normal RNase E levels or the parental strain (TEA028) were treated with mitomycin C (MMC) to induce the phage lytic cycle. Phages and Stx2 titres were quantified by the double-agar assay and the receptor ELISA technique, respectively. RESULTS RNase E deficiency in MMC-treated cells significantly reduced the yield of infectious stx2 phages. Delayed cell lysis and the appearance of encapsidated phage DNA copies suggest a slow onset of the lytic cycle. However, these observations do not entirely explain the decrease of phage yields. stx1 phages were not detected under normal or deficient RNase E levels. After an initial delay, high levels of toxin were finally produced in MMC-treated cultures. CONCLUSION RNase E scarcity reduces stx2 phage production but not toxin. Normal concentrations of RNase E are likely required for correct phage morphogenesis. Our future work will address the mechanism of RNase E action on phage morphogenesis.
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26
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Prevalence, virulence potential, and pulsed-field gel electrophoresis profiling of Shiga toxin-producing Escherichia coli strains from cattle. Gut Pathog 2017; 9:22. [PMID: 28439301 PMCID: PMC5401418 DOI: 10.1186/s13099-017-0169-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 04/07/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND As a primary source of Shiga-toxin-producing Escherichia coli (STEC) infection, cattle are often targeted to develop strategies for reducing STEC contamination. Monitoring the virulence potentials of STEC isolates from cattle is important for tracing contamination sources, managing outbreaks or sporadic cases, and reducing the risks for human infection. This study aimed to investigate the prevalence of STEC in cattle farm samples in South Korea and to assess their virulence potentials. RESULTS In total, 63 STEC were isolated from 496 cattle farm samples, and temperature and rainfall affected STEC prevalence (p < 0.001). The O157 serogroup was most prevalent, followed by O108, O8, O84, O15, and O119. In the stx variant test, high prevalence of stx2a and stx2c (known to be associated with high STEC virulence) were observed, and stx2g, a bovine STEC variant, was detected in STEC O15 and O109. Additionally, stx1c was detected in eae-positive STEC, suggesting genetic dynamics among the virulence genes in the STEC isolates. STEC non-O157 strains were resistant to tetracycline (17.9%), ampicillin (14.3%), and cefotaxime (3.6%), while STEC O157 was susceptible to all tested antimicrobials, except cefotaxime. The antimicrobial resistance genes, blaTEM (17.5%), tetB (6.3%), and tetC (4.8%), were only detected in STEC non-O157, whereas tetE (54.0%) was detected in STEC O157. AmpC was detected in all STEC isolates. Clustering was performed based on the virulence gene profiles, which grouped STEC O84, O108, O111, and O157 together as potentially pathogenic STEC strains. Finally, PFGE suggested the presence of a prototype STEC that continues to evolve by genetic mutation and causes within- and between-farm transmission within the Gyeonggi province. CONCLUSIONS Considerable numbers of STEC non-O157 were isolated from cattle farms, and the virulence and antimicrobial resistance features were different between the STEC O157 and non-O157 strains. STEC from cattle with virulence or antimicrobial resistance genes might represent a threat to public health and therefore, continual surveillance of both STEC O157 and non-O157 would be beneficial for controlling and preventing STEC-related illness.
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27
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Rajaee M, Emami A, Bazargani A, Pirbonyeh N, Moattari A. Identification of serotypes and virulence markers (stx) of Escherichia coli isolated from patients with diarrhea in Shiraz, Iran. GENE REPORTS 2017. [DOI: 10.1016/j.genrep.2016.12.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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28
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Tostes R, Goji N, Amoako K, Chui L, Kastelic J, DeVinney R, Stanford K, Reuter T. Subtyping Escherichia coli Virulence Genes Isolated from Feces of Beef Cattle and Clinical Cases in Alberta. Foodborne Pathog Dis 2016; 14:35-42. [PMID: 27854514 DOI: 10.1089/fpd.2016.2199] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Clinical outcomes of Shiga toxin (stx)-producing Escherichia coli infection are largely determined by virulence gene subtypes. This study used a polymerase chain reaction (PCR)-pyrosequencing assay to analyze single-nucleotide polymorphisms for subtyping three major virulence genes (stx1, stx2, eae) of pathogenic E. coli (O157, O26, O111, and O103) isolated from cattle over a 2-year interval (n = 465) and human clinical cases (n = 42) in western Canada. Most bovine isolates were PCR positive for at least one target virulence gene (367/465), whereas 100% of human isolates harbored eae in combination with at least one stx gene. Four Shiga toxin (1a, 2a, 2c, and 2e) and four eae (λ/γ1-eae, ɛ-eae, θ/γ2-eae, and β-eae) subtypes were identified in over 25 distinct virulence genotypes. Among cattle isolates, every serogroup, but O103, presented a dominant genotype (O157: stx1a+stx2a+λ/γ1-eae, O26: β-eae alone, and O111: stx1a+θ/γ2-eae). Similar patterns were found in human isolates, although it was not possible to establish a clear genotypic association between the two sources. Many O157 and non-O157 cattle isolates lacked stx genes; the absence was greater in non-O157 (75/258) and O157:non-H7 (19/40) than in O157:H7 strains (1/164). In addition, there was a greater diversity of virulence genotypes of E. coli isolated from cattle than those of human diseases, which could be due to sample characteristics (e.g., source and clinical condition). However, the majority of cattle strains had virulence profiles identical to those of clinical cases. Consequently, determining the presence of certain stx (stx1a and stx2a) and eae (λ/γ1-eae) subtypes known to cause human disease would be a valuable tool for risk assessment and prediction of disease outcome along the farm-to-fork continuum.
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Affiliation(s)
- Renata Tostes
- 1 Department of Microbiology, Immunology and Infectious Diseases, University of Calgary , Calgary, Canada
| | - Noriko Goji
- 2 Lethbridge Laboratory, National Centres for Animal Disease, Canadian Food Inspection Agency , Lethbridge, Canada
| | - Kingsley Amoako
- 2 Lethbridge Laboratory, National Centres for Animal Disease, Canadian Food Inspection Agency , Lethbridge, Canada
| | - Linda Chui
- 3 Alberta Provincial Laboratory for Public Health , Edmonton, Canada
| | - John Kastelic
- 4 Faculty of Veterinary Medicine, Production Animal Health, University of Calgary, Calgary, Canada
| | - Rebekah DeVinney
- 1 Department of Microbiology, Immunology and Infectious Diseases, University of Calgary , Calgary, Canada
| | - Kim Stanford
- 5 Alberta Agriculture and Forestry , Lethbridge, Canada
| | - Tim Reuter
- 5 Alberta Agriculture and Forestry , Lethbridge, Canada
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A Rapid Immunoassay for Detection of Shiga Toxin-Producing Escherichia coli Directly from Human Fecal Samples and Its Performance in Detection of Toxin Subtypes. J Clin Microbiol 2016; 54:3056-3063. [PMID: 27733635 PMCID: PMC5121400 DOI: 10.1128/jcm.01785-16] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 10/05/2016] [Indexed: 12/04/2022] Open
Abstract
Fecal samples (n = 531) submitted to a regional clinical laboratory during a 6-month period were tested for the presence of Shiga toxin using both a Vero cell cytotoxicity assay and the Shiga Toxin Quik Chek test (STQC), a rapid membrane immunoassay. Testing the samples directly (without culture), 9 positives were identified by the Vero cell assay, all of which were also detected by the STQC. The correlation between the two assays was 100%. Not all of the identified positive samples were detected when fecal broth cultures were tested. By testing broth cultures of characterized isolates representing all described Shiga toxin subtypes, the STQC detected all subtypes. Levels of induction of toxin production by ciprofloxacin differed among the strains tested, with more toxin induction seen in strains harboring Stx2 phages than in those harboring Stx1 phages.
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Pradhan S, Pellino C, MacMaster K, Coyle D, Weiss AA. Shiga Toxin Mediated Neurologic Changes in Murine Model of Disease. Front Cell Infect Microbiol 2016; 6:114. [PMID: 27747196 PMCID: PMC5040725 DOI: 10.3389/fcimb.2016.00114] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 09/12/2016] [Indexed: 12/22/2022] Open
Abstract
Seizures and neurologic involvement have been reported in patients infected with Shiga toxin (Stx) producing E. coli, and hemolytic uremic syndrome (HUS) with neurologic involvement is associated with more severe outcome. We investigated the extent of renal and neurologic damage in mice following injection of the highly potent form of Stx, Stx2a, and less potent Stx1. As observed in previous studies, Stx2a brought about moderate to acute tubular necrosis of proximal and distal tubules in the kidneys. Brain sections stained with hematoxylin and eosin (H&E) appeared normal, although some red blood cell congestion was observed. Microglial cell responses to neural injury include up-regulation of surface-marker expression (e.g., Iba1) and stereotypical morphological changes. Mice injected with Stx2a showed increased Iba1 staining, mild morphological changes associated with microglial activation (thickening of processes), and increased microglial staining per unit area. Microglial changes were observed in the cortex, hippocampus, and amygdala regions, but not the nucleus. Magnetic resonance imaging (MRI) of Stx2a-treated mice revealed no hyper-intensities in the brain, although magnetic resonance spectroscopy (MRS) revealed significantly decreased levels of phosphocreatine in the thalamus. Less dramatic changes were observed following Stx1 challenge. Neither immortalized microvascular endothelial cells from the cerebral cortex of mice (bEnd.3) nor primary human brain microvascular endothelial cells were found to be susceptible to Stx1 or Stx2a. The lack of susceptibility to Stx for both cell types correlated with an absence of receptor expression. These studies indicate Stx causes subtle, but identifiable changes in the mouse brain.
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Affiliation(s)
- Suman Pradhan
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati Cincinnati, OH, USA
| | | | - Kayleigh MacMaster
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati Cincinnati, OH, USA
| | - Dennis Coyle
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati Cincinnati, OH, USA
| | - Alison A Weiss
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati Cincinnati, OH, USA
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The Accessory Genome of Shiga Toxin-Producing Escherichia coli Defines a Persistent Colonization Type in Cattle. Appl Environ Microbiol 2016; 82:5455-64. [PMID: 27371579 DOI: 10.1128/aem.00909-16] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 06/23/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Shiga toxin-producing Escherichia coli (STEC) strains can colonize cattle for several months and may, thus, serve as gene reservoirs for the genesis of highly virulent zoonotic enterohemorrhagic E. coli (EHEC). Attempts to reduce the human risk for acquiring EHEC infections should include strategies to control such STEC strains persisting in cattle. We therefore aimed to identify genetic patterns associated with the STEC colonization type in the bovine host. We included 88 persistent colonizing STEC (STEC(per)) (shedding for ≥4 months) and 74 sporadically colonizing STEC (STEC(spo)) (shedding for ≤2 months) isolates from cattle and 16 bovine STEC isolates with unknown colonization types. Genoserotypes and multilocus sequence types (MLSTs) were determined, and the isolates were probed with a DNA microarray for virulence-associated genes (VAGs). All STEC(per) isolates belonged to only four genoserotypes (O26:H11, O156:H25, O165:H25, O182:H25), which formed three genetic clusters (ST21/396/1705, ST300/688, ST119). In contrast, STEC(spo) isolates were scattered among 28 genoserotypes and 30 MLSTs, with O157:H7 (ST11) and O6:H49 (ST1079) being the most prevalent. The microarray analysis identified 139 unique gene patterns that clustered with the genoserotypes and MLSTs of the strains. While the STEC(per) isolates possessed heterogeneous phylogenetic backgrounds, the accessory genome clustered these isolates together, separating them from the STEC(spo) isolates. Given the vast genetic heterogeneity of bovine STEC strains, defining the genetic patterns distinguishing STEC(per) from STEC(spo) isolates will facilitate the targeted design of new intervention strategies to counteract these zoonotic pathogens at the farm level. IMPORTANCE Ruminants, especially cattle, are sources of food-borne infections by Shiga toxin-producing Escherichia coli (STEC) in humans. Some STEC strains persist in cattle for longer periods of time, while others are detected only sporadically. Persisting strains can serve as gene reservoirs that supply E. coli with virulence factors, thereby generating new outbreak strains. Attempts to reduce the human risk for acquiring STEC infections should therefore include strategies to control such persisting STEC strains. By analyzing representative genes of their core and accessory genomes, we show that bovine STEC with a persistent colonization type emerged independently from sporadically colonizing isolates and evolved in parallel evolutionary branches. However, persistent colonizing strains share similar sets of accessory genes. Defining the genetic patterns that distinguish persistent from sporadically colonizing STEC isolates will facilitate the targeted design of new intervention strategies to counteract these zoonotic pathogens at the farm level.
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Abstract
Post-infectious hemolytic uremic syndrome (HUS) is caused by specific pathogens in patients with no identifiable HUS-associated genetic mutation or autoantibody. The majority of episodes is due to infections by Shiga toxin (Stx) producing Escherichia coli (STEC). This chapter reviews the epidemiology and pathogenesis of STEC-HUS, including bacterial-derived factors and host responses. STEC disease is characterized by hematological (microangiopathic hemolytic anemia), renal (acute kidney injury) and extrarenal organ involvement. Clinicians should always strive for an etiological diagnosis through the microbiological or molecular identification of Stx-producing bacteria and Stx or, if negative, serological assays. Treatment of STEC-HUS is supportive; more investigations are needed to evaluate the efficacy of putative preventive and therapeutic measures, such as non-phage-inducing antibiotics, volume expansion and anti-complement agents. The outcome of STEC-HUS is generally favorable, but chronic kidney disease, permanent extrarenal, mainly cerebral complication and death (in less than 5 %) occur and long-term follow-up is recommended. The remainder of this chapter highlights rarer forms of (post-infectious) HUS due to S. dysenteriae, S. pneumoniae, influenza A and HIV and discusses potential interactions between these pathogens and the complement system.
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Affiliation(s)
- Denis F. Geary
- Division of Nephrology, The Hospital for Sick Children, Toronto, Ontario Canada
| | - Franz Schaefer
- Division of Pediatric Nephrology, University of Heidelberg, Heidelberg, Germany
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Prevalence of sorbitol non-fermenting Shiga toxin-producing Escherichia coli in Black Bengal goats on smallholdings. Epidemiol Infect 2016; 144:2501-8. [PMID: 27267779 DOI: 10.1017/s0950268816001047] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A cross-sectional survey was carried out in Bangladesh with the sampling of 514 Black Bengal goats on smallholdings to determine the presence of sorbitol non-fermenting (SNF) Shiga toxin-producing E. coli (STEC). Swab samples collected from the recto-anal junction were plated onto cefixime and potassium tellurite added sorbitol MacConkey (CT-SMAC) agar, a selective medium for STEC O157 serogroup, where this serogroup and other SNF STEC produce colourless colonies. The SNF E. coli (SNF EC) isolates obtained from the survey were investigated by PCR for the presence of Shiga toxin-producing genes, stx1 and stx2, and two other virulence genes, eae and hlyA that code for adherence factor (intimin protein) and pore-forming cytolysin, respectively. The SNF EC isolates were also assessed for the presence of the rfbO157 gene to verify their identity to O157 serogroup. The results revealed that the proportions of goats carrying SNF EC isolates and stx1 and stx2 genes were 6·2% (32/514) [95% confidence interval (CI) 4·4-8·7)], 1·2% (95% CI 0·5-2·6) and 1·2% (95% CI 0·5-2·6), respectively. All the SNF STEC tested negative for rfbO157, hlyA and eae genes. The risk for transmission of STEC from Black Bengal goats to humans is low.
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Egan M, Ramirez J, Xander C, Upreti C, Bhatt S. Lambda Red-mediated Recombineering in the Attaching and Effacing Pathogen Escherichia albertii. Biol Proced Online 2016; 18:3. [PMID: 26843851 PMCID: PMC4739404 DOI: 10.1186/s12575-015-0032-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2015] [Accepted: 12/29/2015] [Indexed: 02/06/2023] Open
Abstract
Background The ability to introduce site-specific mutations in bacterial pathogens is essential towards understanding their molecular mechanisms of pathogenicity. This has been greatly facilitated by the genetic engineering technique of recombineering. In recombineering, linear double- or single-stranded DNA molecules with two terminal homology arms are electroporated into hyperrecombinogenic bacteria that express a phage-encoded recombinase. The recombinase catalyzes the replacement of the endogenous allele with the exogenous allele to generate selectable or screenable recombinants. In particular, lambda red recombinase has been instrumental in engineering mutations to characterize the virulence arsenal of the attaching and effacing (A/E) pathogens enteropathogenic Escherichia coli (EPEC), enterohemorrhagic E. coli (EHEC), and Citrobacter rodentium. Escherichia albertii is another member of this taxon; however, the virulence of E. albertii remains cryptic despite accumulating evidence that E. albertii is an emerging pathogen. Multiple retrospective studies have reported that a substantial number of EPEC and EHEC isolates (~15 %) that were previously incriminated in human outbreaks actually belong to the E. albertii lineage. Thus, there is increased urgency to reliably identify and rapidly engineer mutations in E. albertii to systematically characterize its virulence determinants. To the best of our knowledge not a single chromosomal gene has been altered by targeted mutagenesis in E. albertii since it was first isolated almost 25 years ago. This is disconcerting because an E. albertii outbreak could cause significant morbidity and mortality owing to our inadequate understanding of its virulence program. Results In this report we describe a modified lambda red recombineering protocol to mutagenize E. albertii. As proof of principle, we successfully deleted three distinct virulence-associated genetic loci – ler, grlRA, and hfq – and replaced each wild type allele by a mutant allele with an encodable drug resistance cassette bracketed by FRT sites. Subsequently, the FRT-site flanked drug resistance marker was evicted by FLP-dependent site-specific recombination to generate excisants containing a solitary FRT site. Conclusions Our protocol will enable researchers to construct marked and unmarked genome-wide mutations in E. albertii, which, in turn, will illuminate its molecular mechanisms of pathogenicity and aid in developing appropriate preventative and therapeutic approaches to combat E. albertii outbreaks.
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Affiliation(s)
- Marisa Egan
- Department of Biology, Saint Joseph's University, 5600 City Avenue, Philadelphia, PA 19131 USA ; Department of Mathematics, Saint Joseph's University, 5600 City Avenue, Philadelphia, PA 19131 USA
| | - Jasmine Ramirez
- Department of Biology, Saint Joseph's University, 5600 City Avenue, Philadelphia, PA 19131 USA ; Present address: Microbiology Department, Perelman School of Medicine, University of Pennsylvania, 3610 Hamilton Walk, 221 Johnson Pavilion, Philadelphia, PA 19104 USA
| | - Christian Xander
- Department of Biology, Saint Joseph's University, 5600 City Avenue, Philadelphia, PA 19131 USA ; Present address: Bluemle Life Sciences Building, Thomas Jefferson University, 233 South Tenth Street, Philadelphia, PA 19107 USA
| | - Chirag Upreti
- Howard Hughes Medical Institute, Columbia University Medical Center, Columbia, USA ; Columbia University Medical Center, 1051 Riverside Drive, New York, NY 10032 USA
| | - Shantanu Bhatt
- Department of Biology, Saint Joseph's University, 5600 City Avenue, Philadelphia, PA 19131 USA
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Steiner TS. New Insights Into Shiga Toxigenic Escherichia coli Pathogenesis: When Less Is More. J Infect Dis 2016; 213:1214-5. [PMID: 26743844 DOI: 10.1093/infdis/jiv558] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 11/16/2015] [Indexed: 11/14/2022] Open
Affiliation(s)
- Theodore S Steiner
- Department of Medicine, Division of Infectious Diseases, University of British Columbia, Vancouver, Canada
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Shen J, Rump L, Ju W, Shao J, Zhao S, Brown E, Meng J. Virulence characterization of non-O157 Shiga toxin-producing Escherichia coli isolates from food, humans and animals. Food Microbiol 2015; 50:20-7. [DOI: 10.1016/j.fm.2015.02.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 02/10/2015] [Accepted: 02/12/2015] [Indexed: 10/24/2022]
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Sanjar F, Rusconi B, Hazen TH, Koenig SSK, Mammel MK, Feng PCH, Rasko DA, Eppinger M. Characterization of the pathogenome and phylogenomic classification of enteropathogenic Escherichia coli of the O157:non-H7 serotypes. Pathog Dis 2015; 73:ftv033. [PMID: 25962987 DOI: 10.1093/femspd/ftv033] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/01/2015] [Indexed: 12/20/2022] Open
Abstract
Escherichia coli of the O157 serogroup are comprised of a diverse collection of more than 100 O157:non-H7 serotypes that are found in the environment, animal reservoir and infected patients and some have been linked to severe outbreaks of human disease. Among these, the enteropathogenic E. coli O157:non-H7 serotypes carry virulence factors that are hallmarks of enterohemorrhagic E. coli, such as causing attaching and effacing lesions during human gastrointestinal tract infections. Given the shared virulence gene pool between O157:H7 and O157:non-H7 serotypes, our objective was to examine the prevalence of virulence traits of O157:non-H7 serotypes within and across their H-serotype and when compared to other E. coli pathovars. We sequenced six O157:non-H7 genomes complemented by four genomes from public repositories in an effort to determine their virulence state and genetic relatedness to the highly pathogenic enterohemorrhagic O157:H7 lineage and its ancestral O55:H7 serotype. Whole-genome-based phylogenomic analysis and molecular typing is indicative of a non-monophyletic origin of the heterogeneous O157:non-H7 serotypes that are only distantly related to the O157:H7 serotype. The availability of multiple genomes enables robust phylogenomic placement of these strains into their evolutionary context, and the assessment of the pathogenic potential of the O157:non-H7 strains in causing human disease.
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Affiliation(s)
- Fatemeh Sanjar
- Department of Biology & South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Brigida Rusconi
- Department of Biology & South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Tracy H Hazen
- Institute for Genome Sciences (IGS), University of Maryland, School of Medicine, Department of Microbiology and Immunology, Baltimore, MD 21021, USA
| | - Sara S K Koenig
- Department of Biology & South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Mark K Mammel
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, Laurel, MD 20708, USA
| | - Peter C H Feng
- Division of Microbiology, U.S. Food and Drug Administration, College Park, MD 20740, USA
| | - David A Rasko
- Institute for Genome Sciences (IGS), University of Maryland, School of Medicine, Department of Microbiology and Immunology, Baltimore, MD 21021, USA
| | - Mark Eppinger
- Department of Biology & South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX 78249, USA
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Shimizu T, Hirai S, Yokoyama E, Ichimura K, Noda M. An evolutionary analysis of nitric oxide reductase gene norV in enterohemorrhagic Escherichia coli O157. INFECTION GENETICS AND EVOLUTION 2015; 33:176-81. [PMID: 25936496 DOI: 10.1016/j.meegid.2015.04.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 04/29/2015] [Accepted: 04/30/2015] [Indexed: 11/24/2022]
Abstract
A novel virulence gene, norV, that encodes nitric oxide (NO) reductase, was examined to investigate the emergence of enterohemorrhagic Escherichia coli (EHEC) O157 subgroup C clusters 2 and 3 from subgroup C cluster 1. Deletion of norV occurred at a point between cluster 1 and cluster 2 just after or at the same time that an stx2 bacteriophage, which retains Shiga toxin 2 gene, was inserted into wrbA, which encodes a novel multimeric flavodoxin-like protein, in EHEC O157. Sensitivity of NO to anaerobic growth was correlated with the deletion of norV in all EHEC O157 individuals tested. The C467A mutation of fimH, which encodes minor component of type 1 fimbriae, occurred within cluster 1, not as a transition from cluster 1 to cluster 2, indicating that there is a cluster 1 minority branch that leads to cluster 2. These data refine the evolutionary history of an emerging EHEC O157.
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Affiliation(s)
- Takeshi Shimizu
- Department of Molecular Infectiology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chiba 260-8670, Japan.
| | - Shinichiro Hirai
- Division of Bacteriology, Chiba Prefectural Institute of Public Health, 666-2 Nitona, Chiba 260-8715, Japan
| | - Eiji Yokoyama
- Division of Bacteriology, Chiba Prefectural Institute of Public Health, 666-2 Nitona, Chiba 260-8715, Japan
| | - Kimitoshi Ichimura
- Department of Molecular Infectiology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chiba 260-8670, Japan
| | - Masatoshi Noda
- Department of Molecular Infectiology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chiba 260-8670, Japan
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Lambert D, Carrillo CD, Koziol AG, Manninger P, Blais BW. GeneSippr: a rapid whole-genome approach for the identification and characterization of foodborne pathogens such as priority Shiga toxigenic Escherichia coli. PLoS One 2015; 10:e0122928. [PMID: 25860693 PMCID: PMC4393293 DOI: 10.1371/journal.pone.0122928] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 02/24/2015] [Indexed: 12/14/2022] Open
Abstract
The timely identification and characterization of foodborne bacteria for risk assessment purposes is a key operation in outbreak investigations. Current methods require several days and/or provide low-resolution characterization. Here we describe a whole-genome-sequencing (WGS) approach (GeneSippr) enabling same-day identification of colony isolates recovered from investigative food samples. The identification of colonies of priority Shiga-toxigenic Escherichia coli (STEC) (i.e., serogroups O26, O45, O103, O111, O121, O145 and O157) served as a proof of concept. Genomic DNA was isolated from single colonies and sequencing was conducted on the Illumina MiSeq instrument with raw data sampling from the instrument following 4.5 hrs of sequencing. Modeling experiments indicated that datasets comprised of 21-nt reads representing approximately 4-fold coverage of the genome were sufficient to avoid significant gaps in sequence data. A novel bioinformatic pipeline was used to identify the presence of specific marker genes based on mapping of the short reads to reference sequence libraries, along with the detection of dispersed conserved genomic markers as a quality control metric to assure the validity of the analysis. STEC virulence markers were correctly identified in all isolates tested, and single colonies were identified within 9 hrs. This method has the potential to produce high-resolution characterization of STEC isolates, and whole-genome sequence data generated following the GeneSippr analysis could be used for isolate identification in place of lengthy biochemical characterization and typing methodologies. Significant advantages of this procedure include ease of adaptation to the detection of any gene marker of interest, as well as to the identification of other foodborne pathogens for which genomic markers have been defined.
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Affiliation(s)
- Dominic Lambert
- Research and Development, Ottawa Laboratory Carling, Science Branch, Canadian Food Inspection Agency, Ottawa, Ontario, Canada
| | - Catherine D. Carrillo
- Research and Development, Ottawa Laboratory Carling, Science Branch, Canadian Food Inspection Agency, Ottawa, Ontario, Canada
| | - Adam G. Koziol
- Research and Development, Ottawa Laboratory Carling, Science Branch, Canadian Food Inspection Agency, Ottawa, Ontario, Canada
| | - Paul Manninger
- Research and Development, Ottawa Laboratory Carling, Science Branch, Canadian Food Inspection Agency, Ottawa, Ontario, Canada
| | - Burton W. Blais
- Research and Development, Ottawa Laboratory Carling, Science Branch, Canadian Food Inspection Agency, Ottawa, Ontario, Canada
- * E-mail:
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Bonardi S, Alpigiani I, Tozzoli R, Vismarra A, Zecca V, Greppi C, Bacci C, Bruini I, Brindani F. Shiga toxin-producing Escherichia coli O157, O26 and O111 in cattle faeces and hides in Italy. Vet Rec Open 2015; 2:e000061. [PMID: 26392887 PMCID: PMC4567145 DOI: 10.1136/vetreco-2014-000061] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Revised: 09/17/2014] [Accepted: 11/24/2014] [Indexed: 11/20/2022] Open
Abstract
INTRODUCTION Ruminants are regarded as the natural reservoir for Shiga toxin-producing Escherichia coli (STEC), especially of serogroup O157. MATERIALS AND METHODS During 2011 and 2012, 320 samples (160 faecal samples from the rectum and 160 hide samples from the brisket area) were collected from 160 cattle at slaughter in Northern Italy during warm months (May to October). Cattle were reared in different farms and their age at slaughter ranged between nine months and 15 years, most of them being culled cattle (median age: six years; average age: 4.6 years). Samples were tested by immunomagnetic-separation technique for E coli O157 and O26 and by a screening PCR for stx genes followed by cultural detection of STEC. The virulence genes stx1, stx2, eae, and e-hlyA were detected and among stx2-positive isolates the presence of the stx2a and stx2c variants was investigated. RESULTS Twenty-one of 160 cattle (13.1 per cent; 95 per cent CI 8.3 to 19.4 per cent) were found to be faecal carriers of STEC. STEC O157 was found in 10 (6.3 per cent) samples, STEC O26 in six (3.8 per cent) and STEC O111 in one (0.6 per cent). Four isolates (2.5 per cent) were O not determined (OND). Six out of 160 (3.8 per cent; 95 per cent CI 1.4 to 8.0 per cent) hide samples were positive for STEC; four hides (2.5 per cent) were contaminated by STEC O157 and two (1.3 per cent) by STEC O26. In three cattle (1.9 per cent) STEC from both faeces and hides were detected. Among STEC O157, 87.5 per cent of them carried the stx2c gene and 12.5 per cent carried both stx1 and stx2c genes. No O157 isolate harboured stx2a variant. STEC O26 and O111 carried the stx1 gene only. One OND strain carried both the stx2a and stx2c genes. CONCLUSIONS This study shows that STEC O157 from cattle can harbour the stx2c variant, which is associated with haemolytic uraemic syndrome in humans, and that cattle hides may be a source of human pathogenic STEC O157 and O26 in the slaughterhouse environment.
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Affiliation(s)
- S Bonardi
- Department of Veterinary Science, Unit of Food Hygiene , University of Parma , Parma , Italy
| | - I Alpigiani
- Department of Veterinary Science, Unit of Food Hygiene , University of Parma , Parma , Italy
| | - R Tozzoli
- Department of Veterinary Public Health and Food Safety , Istituto Superiore di Sanità , Rome , Italy
| | - A Vismarra
- Department of Veterinary Science, Unit of Food Hygiene , University of Parma , Parma , Italy
| | - V Zecca
- Department of Veterinary Science, Unit of Food Hygiene , University of Parma , Parma , Italy
| | - C Greppi
- National Health Service, Veterinary Service, Local Unit of Cremona , Italy
| | - C Bacci
- Department of Veterinary Science, Unit of Food Hygiene , University of Parma , Parma , Italy
| | - I Bruini
- Department of Veterinary Science, Unit of Food Hygiene , University of Parma , Parma , Italy
| | - F Brindani
- Department of Veterinary Science, Unit of Food Hygiene , University of Parma , Parma , Italy
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Enhanced virulence of the Escherichia coli O157:H7 spinach-associated outbreak strain in two animal models is associated with higher levels of Stx2 production after induction with ciprofloxacin. Infect Immun 2014; 82:4968-77. [PMID: 25225244 DOI: 10.1128/iai.02361-14] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Shiga toxin (Stx)-producing Escherichia coli (STEC) causes hemorrhagic colitis and the hemolytic-uremic syndrome (HUS). STEC strains may produce Stx1a and/or Stx2a or variants of either toxin. A 2006 spinach-associated outbreak of STEC O157:H7 resulted in higher hospitalization and HUS rates than previous STEC outbreaks. The spinach isolate, strain K3995, contains both stx2a and stx2c. We hypothesized that the enhanced virulence of K3995 reflects the combination of stx2 alleles (carried on lysogenic phages) and/or the amount of Stx2 made by that strain. We compared the virulence of K3995 to those of other O157:H7 isolates and an isogenic Stx2 mutant in rabbits and mice. We also measured the relative levels of Stx2 produced from those strains with or without induction of the stx-carrying phage. Some rabbits infected with K3995 exhibited intestinal pathology and succumbed to infection, while none of those infected with O157:H7 strain 2812 (Stx1a(+) Stx2a(+)) died or showed pathological signs. Rabbits infected with the isogenic Stx2a mutant K3995 stx2a::cat were not colonized as well as those infected with K3995 and exhibited no signs of disease. In the streptomycin-treated mouse model, more animals infected with K3995 died than did those infected with O157:H7 strain 86-24 (Stx2a(+)). Additionally, K3995 produced higher levels of total Stx2 and toxin phage DNA in cultures after phage induction than did 86-24. Our results demonstrate the greater virulence of K3995 compared to other O157:H7 strains in rabbits and mice. We conclude that this enhanced virulence is linked to higher levels of Stx2 expression as a consequence of increased phage induction.
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Humoral immune response to Shiga Toxin 2 (Stx2) among Brazilian urban children with hemolytic uremic syndrome and healthy controls. BMC Infect Dis 2014; 14:320. [PMID: 24919599 PMCID: PMC4060089 DOI: 10.1186/1471-2334-14-320] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Accepted: 05/28/2014] [Indexed: 11/26/2022] Open
Abstract
Background Shiga toxin (Stx)-producing Escherichia coli (STEC) infection is associated with hemolytic uremic syndrome (HUS), the main cause of acute renal failure in early childhood. Stx is essential in the pathogenesis of HUS, which has been mostly related to Stx2-producing isolates. Very limited data exist on the immune response to STEC in the Brazilian population. In this study, the prevalence of immunoglobulin G (IgG) antibodies to Stx2 was investigated in sera of children diagnosed with HUS and of healthy children in the city of São Paulo, Brazil. Methods IgG-antibody reactivity to Stx2 was determined by immunoblotting (WB) and enzyme-linked immunosorbent assay (ELISA) in sera from 13 children with HUS aged 8 months to 6 years and 54 healthy urban children aged 5 months to 7 years. Results A positive immune response to the A and B subunits of Stx2 was observed in 46.1% HUS patients and in 16.6% healthy individuals by WB. All HUS patients and 62.9% healthy children showed IgG antibodies to the Stx2 A subunit. The frequency of antibodies to both subunits or only to the A subunit of Stx2 was significantly higher in HUS patients than controls (p < 0.05). Also, the mean OD value obtained by ELISA was higher in that group. Considering children’s age, the frequency of reactivity to either the A subunit or both subunits of Stx2 was considerably higher in HUS children up to three years old compared to controls in the same age range. Moreover, in almost 37% of healthy children, no immune response to Stx2 was detected independently of the child’s age. Conclusions The seroepidemiolgy of anti-Stx2 antibodies was described for the first time in healthy children and children with HUS in Brazil. The percentage of individuals showing antibodies against Stx2 was higher among HUS patients than controls, and in spite of the low number of notified HUS cases, STEC strains are circulating in our settings. In addition, the results obtained also corroborated previous data on the increased sensitivity and specificity of WB compared to toxin-based enzyme immunoassays.
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Son I, Binet R, Maounounen-Laasri A, Lin A, Hammack TS, Kase JA. Detection of five Shiga toxin-producing Escherichia coli genes with multiplex PCR. Food Microbiol 2014; 40:31-40. [DOI: 10.1016/j.fm.2013.11.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Revised: 11/05/2013] [Accepted: 11/29/2013] [Indexed: 01/04/2023]
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Abstract
ABSTRACT
To help assess the clinical and public health risks associated with different Shiga toxin-producing
Escherichia coli
(STEC) strains, an empirical classification scheme was used to classify STEC into five “seropathotypes” (seropathotype A [high risk] to seropathotypes D and E [minimal risk]). This definition is of considerable value in cases of human infection but is also problematic because not all STEC infections are fully characterized and coupled to reliable clinical information. Outbreaks with emerging hybrid strains continuously challenge our understanding of virulence potential and may result in incorrect classification of specific pathotypes; an example is the hybrid strain that caused the 2011 outbreak in Germany, STEC/EAggEC O104:H4, which may deserve an alternative seropathotype designation. The integration of mobile virulence factors in the stepwise and parallel evolution of pathogenic lineages of STEC collides with the requirements of a good taxonomy, which separates elements of each group into subgroups that are mutually exclusive, unambiguous, and, together, include all possibilities. The concept of (sero)-pathotypes is therefore challenged, and the need to identify factors of STEC that absolutely predict the potential to cause human disease is obvious. Because the definition of hemolytic-uremic syndrome (HUS) is distinct, a basic and primary definition of HUS-associated
E. coli
(HUSEC) for first-line public health action is proposed:
stx2
in a background of an
eae-
or
aggR
-positive
E. coli
followed by a second-line subtyping of
stx
genes that refines the definition of HUSEC to include only
stx2a
and
stx2d
. All other STEC strains are considered “low-risk” STEC.
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Shen J, Wang F, Li F, Housley R, Carolan H, Yasuda I, Burrows E, Binet R, Sampath R, Zhang J, Allard MW, Meng J. Rapid Identification and Differentiation of Non-O157 Shiga Toxin–ProducingEscherichia coliUsing Polymerase Chain Reaction Coupled to Electrospray Ionization Mass Spectrometry. Foodborne Pathog Dis 2013; 10:737-43. [DOI: 10.1089/fpd.2012.1469] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Jinling Shen
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi Province, China
- Department of Nutrition and Food Science, University of Maryland, College Park, Maryland
- Zhangjiagang Entry-Exit Inspection and Quarantine Bureau, Zhangjiagang, Jiangsu Province, China
| | - Fei Wang
- Department of Nutrition and Food Science, University of Maryland, College Park, Maryland
| | - Feng Li
- Ibis Biosciences, Abbott, Carlsbad, California
| | | | | | | | - Erik Burrows
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, Maryland
| | - Rachel Binet
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, Maryland
| | | | | | - Marc W. Allard
- Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, College Park, Maryland
| | - Jianghong Meng
- College of Food Science and Engineering, Northwest A&F University, Yangling, Shaanxi Province, China
- Department of Nutrition and Food Science, University of Maryland, College Park, Maryland
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Shiga toxin-producing Escherichia coli in yaks (Bos grunniens) from the Qinghai-Tibetan Plateau, China. PLoS One 2013; 8:e65537. [PMID: 23776496 PMCID: PMC3679134 DOI: 10.1371/journal.pone.0065537] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Accepted: 04/24/2013] [Indexed: 12/30/2022] Open
Abstract
Shiga toxin (Stx)-producing Escherichia coli (STEC) are recognized as important human pathogens of public health concern. Many animals are the sources of STEC. In this study we determined the occurrence and characteristics of the STEC in yaks (Bos grunniens) from the Qinghai-Tibetan plateau, China. A total of 728 yak fecal samples was collected from June to August, 2012 and was screened for the presence of the stx1 and stx2 genes by TaqMan real-time PCR after the sample was enriched in modified Tryptone Soya Broth. Of the 138 (18.96%) stx1 and/or stx2-positive samples, 85 (61.59%) were confirmed to have at least 1 STEC isolate present by culture isolation, from which 128 STEC isolates were recovered. All STEC isolates were serotyped, genotyped by pulsed-field gel electrophoresis (PFGE) and characterized for the presence of 16 known virulence factors. Fifteen different O serogroups and 36 different O:H serotypes were identified in the 128 STEC isolates with 21 and 4 untypable for the O and H antigens respectively. One stx1 subtype (stx1a) and 5 stx2 subtypes (stx2a, stx2b, stx2c, stx2d and stx2g) were present in these STEC isolates. Apart from lpfAO157/OI-141, lpfAO157/OI-154, lpfAO113, katP and toxB which were all absent, other virulence factors screened (eaeA, iha, efa1, saa, paa, cnf1, cnf2, astA, subA, exhA and espP) were variably present in the 128 STEC isolates. PFGE were successful for all except 5 isolates and separated them into 67 different PFGE patterns. For the 18 serotypes with 2 or more isolates, isolates of the same serotypes had the same or closely related PFGE patterns, demonstrating clonality of these serotypes. This study was the first report on occurrence and characteristics of STEC isolated from yaks (Bos grunniens) from the Qinghai-Tibetan plateau, China, and extended the genetic diversity and reservoir host range of STEC.
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Genetic characteristics of Shiga toxin-producing E. coli O157, O26, O103, O111 and O145 isolates from humans, food, and cattle in Belgium. Epidemiol Infect 2013; 141:2503-15. [PMID: 23445754 DOI: 10.1017/s0950268813000307] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In this study, we characterized 272 Shiga toxin-producing Escherichia coli (STEC) isolates from humans, food, and cattle in Belgium [O157 (n = 205), O26 (n = 31), O103 (n = 15), O111 (n = 10), O145 (n = 11)] for their virulence profile, whole genome variations and relationships on different genetic levels. Isolates of O157 displayed a wide variation of stx genotypes, heterogeneously distributed among pulsogroups (80% similarity), but with a concordance at the pulsosubgroup level (90% similarity). Of all serogroups evaluated, the presence of eae was conserved, whereas genes encoded on the large plasmid (ehx, espP, katP) occurred in variable combinations in O26, O103, and O145. The odds of having haemolytic uraemic syndrome was less for all genotypes stx2a, stx2c, stx1/stx2c, and stx1 compared to genotype stx2a/stx2c; and for patients aged >5 years compared to patients aged ≤ 5 years. Based on the genetic typing and by using epidemiological data, we could confirm outbreak isolates and suggest epidemiological relationships between some sporadic cases. Undistinguishable pulsotypes or clones with minor genotypic variations were found in humans, food, and cattle in different years, which demonstrated the important role of cattle as a reservoir of STEC O157, and the circulation and persistence of pathogenic clones.
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Shringi S, Schmidt C, Katherine K, Brayton KA, Hancock DD, Besser TE. Carriage of stx2a differentiates clinical and bovine-biased strains of Escherichia coli O157. PLoS One 2012; 7:e51572. [PMID: 23240045 PMCID: PMC3519850 DOI: 10.1371/journal.pone.0051572] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Accepted: 11/02/2012] [Indexed: 12/18/2022] Open
Abstract
Background Shiga toxin (Stx) are cardinal virulence factors of enterohemorrhagic E. coli O157:H7 (EHEC O157). The gene content and genomic insertion sites of Stx-associated bacteriophages differentiate clinical genotypes of EHEC O157 (CG, typical of clinical isolates) from bovine-biased genotypes (BBG, rarely identified among clinical isolates). This project was designed to identify bacteriophage-mediated differences that may affect the virulence of CG and BBG. Methods Stx-associated bacteriophage differences were identified by whole genome optical scans and characterized among >400 EHEC O157 clinical and cattle isolates by PCR. Results Optical restriction maps of BBG strains consistently differed from those of CG strains only in the chromosomal insertion sites of Stx2-associated bacteriophages. Multiplex PCRs (stx1, stx2a, and stx2c as well as Stx-associated bacteriophage - chromosomal insertion site junctions) revealed four CG and three BBG that accounted for >90% of isolates. All BBG contained stx2c and Stx2c-associated bacteriophage – sbcB junctions. All CG contained stx2a and Stx2a-associated bacteriophage junctions in wrbA or argW. Conclusions Presence or absence of stx2a (or another product encoded by the Stx2a-associated bacteriophage) is a parsimonious explanation for differential virulence of BBG and CG, as reflected in the distributions of these genotypes in humans and in the cattle reservoir.
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Affiliation(s)
- Smriti Shringi
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, United States of America
| | - Carrie Schmidt
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, United States of America
| | - Kaya Katherine
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, United States of America
| | - Kelly A. Brayton
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, United States of America
| | - Dale D. Hancock
- Department of Veterinary Clinical Sciences, Washington State University, Pullman, Washington, United States of America
| | - Thomas E. Besser
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, United States of America
- * E-mail:
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Comparison of three different methods for detection of Shiga toxin-producing Escherichia coli in a tertiary pediatric care center. J Clin Microbiol 2012; 51:481-6. [PMID: 23175264 DOI: 10.1128/jcm.02219-12] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) is a well-known cause of sporadic and epidemic food-borne gastroenteritis. A low infectious dose, approximately 10 microorganisms, is sufficient to cause disease that may lead to hemolytic-uremic syndrome. The objective of this study was to compare the performances of an in-house real-time PCR, a commercial enzyme immunoassay (EIA) (Premier EHEC; Meridian Bioscience), and culture on sorbitol MacConkey agar for the detection of STEC in a tertiary care pediatric hospital. Of 632 stool samples tested, 21 were positive for STEC. All were detected by PCR, 6 were detected by EIA, and only 5 O157 STEC isolates were identified by culture. Among the 15 specimens falsely negative by EIA, there were 9 Stx1, 2 Stx2, and 4 Stx1 and Stx2 STEC isolates. The latter group included 2 O157 STEC isolates that would have been missed if only EIA had been performed. To our knowledge, this is the first prospective study performed in a pediatric hospital which demonstrates the superiority of PCR over EIA for the detection of STEC. We conclude that PCR is specific and more sensitive than EIA. PCR should be considered for routine use in clinical settings where molecular detection facilities are available. Its lower limit of detection, equivalent to the infectious dose, is an obvious advantage for patient care and public health surveillance.
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