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Samgane G, Karaçam S, Tunçer Çağlayan S. Unveiling the synergistic potency of chlorhexidine and azithromycin in combined action. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2024; 397:5975-5987. [PMID: 38376540 PMCID: PMC11329591 DOI: 10.1007/s00210-024-03010-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 02/12/2024] [Indexed: 02/21/2024]
Abstract
The growing challenge of antibiotic resistance necessitates novel approaches for combating bacterial infections. This study explores the distinctive synergy between chlorhexidine, an antiseptic and disinfectant agent, and azithromycin, a macrolide antibiotic, in their impact on bacterial growth and virulence factors using Escherichia coli strain Crooks (ATCC 8739) as a model. Our findings reveal that the chlorhexidine and azithromycin combination demonstrates enhanced anti-bacterial effects compared to individual treatments. Intriguingly, the combination induced oxidative stress, decreased flagellin expression, impaired bacterial motility, and enhanced bacterial autoaggregation. Notably, the combined treatment also demonstrated a substantial reduction in bacterial adherence to colon epithelial cells and downregulated NF-κB in the epithelial cells. In conclusion, these results shed light on the potential of the chlorhexidine and azithromycin synergy as a compelling strategy to address the rising challenge of antibiotic resistance and may pave the way for innovative therapeutic interventions in tackling bacterial infections.
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Affiliation(s)
- Gizem Samgane
- Department of Biotechnology, Bilecik Şeyh Edebali University, Bilecik, 11100, Turkey
| | - Sevinç Karaçam
- Department of Biotechnology, Bilecik Şeyh Edebali University, Bilecik, 11100, Turkey
- Central Research and Application Laboratory, Bilecik Şeyh Edebali University, Bilecik, 11100, Turkey
| | - Sinem Tunçer Çağlayan
- Department of Medical Services and Techniques, Vocational School of Health Services, Bilecik Şeyh Edebali University, Pelitözü Mah. Fatih Sultan Mehmet Bulvarı No:27, Bilecik, 11100, Turkey.
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Bulgan E, Byambajav Z, Ayushjav N, Hirai Y, Tanaka M, Purevdorj NO, Badrakh S, Suzuki A, Komatsu Y, Sato T, Horiuchi M. Characterization of Shiga Toxin-producing Escherichia coli Isolated from Cattle Around Ulaanbaatar City, Mongolia. J Food Prot 2024; 87:100294. [PMID: 38718985 DOI: 10.1016/j.jfp.2024.100294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 04/26/2024] [Accepted: 04/30/2024] [Indexed: 06/04/2024]
Abstract
Shiga toxin-producing Escherichia coli (STEC) are associated with severe infections including hemorrhagic colitis and hemolytic uremic syndrome in humans. Ruminants are known as reservoirs of STEC; however, no data are available on STEC in ruminants in Mongolia, where more than 5 million cattle and 25 million sheep are raised. To disclose the existence and characteristics of STEC in Mongolia, in this study, we isolated and characterized STEC from cattle in Mongolia. We collected 350 rectal swabs of cattle from 30 farms near Ulaanbaatar city and isolated 45 STEC from 21 farms. Rectal swabs were precultured with modified Escherichia coli broth and then inoculated to Cefixime-Tellurite Sorbitol MacConkey agar plate and/or CHROMagar STEC agar plate for the isolation of STEC. The isolation ratios in each farm were from 0% to 40%. Multiplex PCR for the estimation of O- and H-serotypes identified 12 O-genotypes (Og-types) and 11 H-genotypes (Hg-types) from 45 isolates; however, Og-types of 19 isolates could not be determined. Stx gene subtyping by PCR identified 2 stx1 subtypes (1a and 1c) and 4 stx2 subtypes (2a, 2c, 2d, and 2g). Forty-five isolates were divided into 21 different groups based on the Og- and Hg-types, stx gene subtypes and the existence of virulence factors, ehxA, eae, and saa, which includes several major serotypes associated with human illness such as O26:H11 and O157:H7. The most dominant isolate, OgUT:H19 [stx1a (+), stx2a (+), ehxA (+) and saa (+)], was isolated from eight farms. This is the first report on the characterization of STEC in cattle in Mongolia, and the results suggest the importance of further monitoring of STEC contamination in the food chains as well as STEC infection in humans.
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Affiliation(s)
- Erdenebat Bulgan
- Laboratory of Veterinary Hygiene, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo 060-0818, Japan
| | - Zolzaya Byambajav
- Laboratory of Veterinary Sanitation and Hygiene, Ulaanbaatar Veterinary Department, Chinguunjav Street, 2nd Khoroo, Bayangol District, Ulaanbaatar 16050, Mongolia
| | - Narantuya Ayushjav
- Laboratory of Veterinary Sanitation and Hygiene, Ulaanbaatar Veterinary Department, Chinguunjav Street, 2nd Khoroo, Bayangol District, Ulaanbaatar 16050, Mongolia
| | - Yuji Hirai
- Laboratory of Veterinary Hygiene, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo 060-0818, Japan
| | - Misaki Tanaka
- Laboratory of Veterinary Hygiene, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo 060-0818, Japan
| | - Nyam-Osor Purevdorj
- School of Veterinary Medicine, Mongolian University of Life Science, Zaisan, Khan-Uul, Ulaanbaatar 17024, Mongolia
| | - Sandagdorj Badrakh
- School of Veterinary Medicine, Mongolian University of Life Science, Zaisan, Khan-Uul, Ulaanbaatar 17024, Mongolia
| | - Akio Suzuki
- Laboratory of Veterinary Hygiene, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo 060-0818, Japan; One Health Research Center, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo 060-0818, Japan
| | - Yusuke Komatsu
- Laboratory of Veterinary Hygiene, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo 060-0818, Japan
| | - Toyotaka Sato
- Laboratory of Veterinary Hygiene, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo 060-0818, Japan; One Health Research Center, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo 060-0818, Japan
| | - Motohiro Horiuchi
- Laboratory of Veterinary Hygiene, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo 060-0818, Japan; One Health Research Center, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo 060-0818, Japan.
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Vidal RM, Montero DA, Bentancor A, Arellano C, Alvarez A, Cundon C, Blanco Crivelli X, Del Canto F, Salazar JC, Oñate AA. Evaluation of the Humoral Response after Immunization with a Chimeric Subunit Vaccine against Shiga Toxin-Producing Escherichia coli in Pregnant Sows and Their Offspring. Vaccines (Basel) 2024; 12:726. [PMID: 39066363 PMCID: PMC11281613 DOI: 10.3390/vaccines12070726] [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: 04/23/2024] [Revised: 05/27/2024] [Accepted: 06/01/2024] [Indexed: 07/28/2024] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) poses a significant public health risk due to its zoonotic potential and association with severe human diseases, such as hemorrhagic colitis and hemolytic uremic syndrome. Ruminants are recognized as primary reservoirs for STEC, but swine also contribute to the epidemiology of this pathogen, highlighting the need for effective prevention strategies across species. Notably, a subgroup of STEC that produces Shiga toxin type 2e (Stx2e) causes edema disease (ED) in newborn piglets, economically affecting pig production. This study evaluates the immunogenicity of a chimeric protein-based vaccine candidate against STEC in pregnant sows and the subsequent transfer of immunity to their offspring. This vaccine candidate, which includes chimeric proteins displaying selected epitopes from the proteins Cah, OmpT, and Hes, was previously proven to be immunogenic in pregnant cows. Our analysis revealed a broad diversity of STEC serotypes within swine populations, with the cah and ompT genes being prevalent, validating them as suitable antigens for vaccine development. Although the hes gene was detected less frequently, the presence of at least one of these three genes in a significant proportion of STEC suggests the potential of this vaccine to target a wide range of strains. The vaccination of pregnant sows led to an increase in specific IgG and IgA antibodies against the chimeric proteins, indicating successful immunization. Additionally, our results demonstrated the effective passive transfer of maternal antibodies to piglets, providing them with immediate, albeit temporary, humoral immunity against STEC. These humoral responses demonstrate the immunogenicity of the vaccine candidate and are preliminary indicators of its potential efficacy. However, further research is needed to conclusively evaluate its impact on STEC colonization and shedding. This study highlights the potential of maternal vaccination to protect piglets from ED and contributes to the development of vaccination strategies to reduce the prevalence of STEC in various animal reservoirs.
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Affiliation(s)
- Roberto M. Vidal
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile; (C.A.); (A.A.); (F.D.C.); (J.C.S.)
- Instituto Milenio de Inmunología e Inmunoterapia, Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile
| | - David A. Montero
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile; (C.A.); (A.A.); (F.D.C.); (J.C.S.)
- Centro Integrativo de Biología y Química Aplicada (CIBQA), Universidad Bernardo O’Higgins, Santiago 8320000, Chile
| | - Adriana Bentancor
- Universidad de Buenos Aires, Facultad de Ciencias Veterinarias, Instituto de Investigaciones en Epidemiología Veterinaria, Cátedra de Microbiología, Buenos Aires C1427CWO, Argentina; (A.B.); (C.C.)
| | - Carolina Arellano
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile; (C.A.); (A.A.); (F.D.C.); (J.C.S.)
| | - Alhejandra Alvarez
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile; (C.A.); (A.A.); (F.D.C.); (J.C.S.)
| | - Cecilia Cundon
- Universidad de Buenos Aires, Facultad de Ciencias Veterinarias, Instituto de Investigaciones en Epidemiología Veterinaria, Cátedra de Microbiología, Buenos Aires C1427CWO, Argentina; (A.B.); (C.C.)
| | - Ximena Blanco Crivelli
- Universidad de Buenos Aires, Facultad de Ciencias Veterinarias, Instituto de Investigaciones en Epidemiología Veterinaria, Cátedra de Microbiología, Buenos Aires C1427CWO, Argentina; (A.B.); (C.C.)
| | - Felipe Del Canto
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile; (C.A.); (A.A.); (F.D.C.); (J.C.S.)
| | - Juan C. Salazar
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago 8380453, Chile; (C.A.); (A.A.); (F.D.C.); (J.C.S.)
| | - Angel A. Oñate
- Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción 4070386, Chile;
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Vélez MV, Colello R, Nieto MV, Paz LE, Etcheverría AI, Vidal R, Padola NL. Transcription levels of hes and their involvement in the biofilm formation of Shiga toxin-producing Escherichia coli O91. Vet Res Commun 2024; 48:1821-1830. [PMID: 38263503 DOI: 10.1007/s11259-024-10308-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 01/10/2024] [Indexed: 01/25/2024]
Abstract
Shiga toxin-producing Escherichia coli (STEC) are recognized as being responsible for many cases of foodborne diseases worldwide. Cattle are the main reservoir of STEC, shedding the microorganisms in their feces. The serogroup STEC O91 has been associated with hemorrhagic colitis and hemolytic uremic syndrome. Locus of Adhesion and Autoaggregation (LAA) and its hes gene are related to the pathogenicity of STEC and the ability to form biofilms. Considering the frequent isolation of STEC O91, the biofilm-forming ability, and the possible role of hes in the pathogenicity of STEC, we propose to evaluate the ability of STEC to form biofilms and to evaluate the expression of hes before and after of biofilm formation. All strains were classified as strong biofilm-forming. The hes expression showed variability between strains before and after biofilm formation, and this may be due to other genes carried by each strain. This study is the first to report the relationship between biofilm formation, and hes expression and proposes that the analysis and diagnosis of LAA, especially hes as STEC O91 virulence factors, could elucidate these unknown mechanisms. Considering that there is no specific treatment for HUS, only supportive care, it is necessary to know the survival and virulence mechanisms of STEC O91.
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Affiliation(s)
- María Victoria Vélez
- Facultad de Cs. Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), CISAPA, Tandil, Buenos Aires, Argentina
- Centro de Investigación Veterinaria de Tandil (CIVETAN), UNCPBA-CICPBA-CONICET, Tandil, Buenos Aires, Argentina
| | - Rocío Colello
- Facultad de Cs. Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), CISAPA, Tandil, Buenos Aires, Argentina
- Centro de Investigación Veterinaria de Tandil (CIVETAN), UNCPBA-CICPBA-CONICET, Tandil, Buenos Aires, Argentina
| | - María Victoria Nieto
- Facultad de Cs. Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), CISAPA, Tandil, Buenos Aires, Argentina
- Centro de Investigación Veterinaria de Tandil (CIVETAN), UNCPBA-CICPBA-CONICET, Tandil, Buenos Aires, Argentina
| | - Laura Estefanía Paz
- Facultad de Cs. Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), SAMP, Tandil, Buenos Aires, Argentina
- Instituto Multidisciplinario sobre Ecosistemas y Desarrollo Sustentable, CONICET, Tandil, Buenos Aires, Argentina
| | - Analía Inés Etcheverría
- Facultad de Cs. Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), CISAPA, Tandil, Buenos Aires, Argentina
- Centro de Investigación Veterinaria de Tandil (CIVETAN), UNCPBA-CICPBA-CONICET, Tandil, Buenos Aires, Argentina
| | - Roberto Vidal
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Nora Lía Padola
- Facultad de Cs. Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), CISAPA, Tandil, Buenos Aires, Argentina.
- Centro de Investigación Veterinaria de Tandil (CIVETAN), UNCPBA-CICPBA-CONICET, Tandil, Buenos Aires, Argentina.
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Rodwell EV, Greig DR, Godbole G, Jenkins C. Clinical and public health implications of increasing notifications of LEE-negative Shiga toxin-producing Escherichia coli in England, 2014-2022. J Med Microbiol 2024; 73. [PMID: 38299580 DOI: 10.1099/jmm.0.001790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2024] Open
Abstract
Introduction. Shiga toxin-producing Escherichia coli (STEC) belong to a diverse group of gastrointestinal pathogens. The pathogenic potential of STEC is enhanced by the presence of the pathogenicity island called the Locus of Enterocyte Effacement (LEE), including the intimin encoding gene eae.Gap statement. STEC serotypes O128:H2 (Clonal Complex [CC]25), O91:H14 (CC33), and O146:H21 (CC442) are consistently in the top five STEC serotypes isolated from patients reporting gastrointestinal symptoms in England. However, they are eae/LEE-negative and perceived to be a low risk to public health, and we know little about their microbiology and epidemiology.Aim. We analysed clinical outcomes and genome sequencing data linked to patients infected with LEE-negative STEC belonging to CC25 (O128:H2, O21:H2), CC33 (O91:H14) and, and CC442 (O146:H21, O174:H21) in England to assess the risk to public health.Results. There was an almost ten-fold increase between 2014 and 2022 in the detection of all STEC belonging to CC25, CC33 and CC442 (2014 n=38, 2022 n=336), and a total of 1417 cases. There was a higher proportion of female cases (55-70 %) and more adults than children, with patients aged between 20-40 and >70 most at risk across the different serotypes. Symptoms were consistent across the three dominant serotypes O91:H14 (CC33), O146:H21 (CC442) and O128:H2 (CC25) (diarrhoea >75 %; bloody diarrhoea 25-32 %; abdominal pain 64-72 %; nausea 37-45 %; vomiting 10-24 %; and fever 27-30 %). Phylogenetic analyses revealed multiple events of acquisition and loss of different stx-encoding prophage. Additional putative virulence genes were identified including iha, agn43 and subA.Conclusions. Continued monitoring and surveillance of LEE-negative STEC infections is essential due to the increasing burden of infectious intestinal disease, and the risk that highly pathogenic strains may emerge following acquisition of the Shiga toxin subtypes associated with the most severe clinical outcomes.
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Affiliation(s)
- Ella V Rodwell
- National Infection Service, UK Health Security Agency, 61 Colindale Avenue, London, NW9 5AT, UK
- Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK
- NIHR HPRU in Gastrointestinal Infections at University of Liverpool, Liverpool, UK
| | - David R Greig
- National Infection Service, UK Health Security Agency, 61 Colindale Avenue, London, NW9 5AT, UK
| | - Gauri Godbole
- National Infection Service, UK Health Security Agency, 61 Colindale Avenue, London, NW9 5AT, UK
| | - Claire Jenkins
- National Infection Service, UK Health Security Agency, 61 Colindale Avenue, London, NW9 5AT, UK
- NIHR HPRU in Gastrointestinal Infections at University of Liverpool, Liverpool, UK
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Giraldo-Rubio V, Arango-Gil BS, Granobles-Velandia CV. First report of the prevalence of Shiga toxinproducing Escherichia coli in ground beef in Quindío, Colombia. BIOMEDICA : REVISTA DEL INSTITUTO NACIONAL DE SALUD 2023; 43:474-482. [PMID: 38109140 PMCID: PMC10781425 DOI: 10.7705/biomedica.7004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 10/23/2023] [Indexed: 12/19/2023]
Abstract
INTRODUCTION Shiga toxin-producing Escherichia coli (STEC) is a foodborne pathogen associated with clinical cases of diarrhea in humans. Its main virulence factors are the Shiga toxins (Stx1 and Stx2). Cattle are the main reservoir of STEC, and many outbreaks in humans have been related to the consumption of undercooked ground beef contaminated with this pathogen. OBJECTIVE To determine the prevalence of STEC in ground beef commercialized in all the butcher shops of a township in the department of Quindío and to characterize the virulence genes of the strains found. MATERIALS AND METHODS Thirty ground beef samples were taken in three different times; stx genes and other STEC virulence factors (eae, ehxA, saa) were detected by multiplex PCR. RESULTS The overall prevalence of STEC was 33.33 % (10/30 positive samples). We isolated eight non-O157 (LEE-negative) strains with four different genetic profiles: stx2 / stx2-ehxA-saa / stx1-stx2-ehxA-saa / stx1-saa. CONCLUSION This is the first report on the prevalence of STEC in ground beef in a township in the department of Quindío.
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Affiliation(s)
- Valentina Giraldo-Rubio
- Grupo de Inmunología Molecular (GYMOL), Centro de Investigaciones Biomédicas, Universidad del Quindío, Armenia, Colombia.
| | - Brayan Stiven Arango-Gil
- Grupo de Inmunología Molecular (GYMOL), Centro de Investigaciones Biomédicas, Universidad del Quindío, Armenia, Colombia.
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Carter MQ, Quiñones B, Laniohan N, Carychao D, Pham A, He X, Cooley M. Pathogenicity assessment of Shiga toxin-producing Escherichia coli strains isolated from wild birds in a major agricultural region in California. Front Microbiol 2023; 14:1214081. [PMID: 37822735 PMCID: PMC10562709 DOI: 10.3389/fmicb.2023.1214081] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 09/11/2023] [Indexed: 10/13/2023] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) consists of diverse strains differing in genetic make-up and virulence potential. To better understand the pathogenicity potential of STEC carried by the wildlife, three STEC and one E. coli strains isolated from wild birds near a major agricultural region in California were selected for comparative pathogenomic analyses. Three American crow (Corvus brachyrhynchos) strains, RM9088, RM9513, and RM10410, belonging to phylogroup A with serotypes O109:H48, O9:H30, and O113:H4, respectively, and a red-winged blackbird (Agelaius phoeniceus) strain RM14516 in phylogroup D with serotype O17:H18, were examined. Shiga toxin genes were identified in RM9088 (stx1a), RM10410 (stx1a + stx2d), and RM14516 (stx2a). Unlike STEC O157:H7 strain EDL933, none of the avian STEC strains harbored the pathogenicity islands OI-122, OI-57, and the locus of enterocyte effacement, therefore the type III secretion system biogenesis genes and related effector genes were absent in the three avian STEC genomes. Interestingly, all avian STEC strains exhibited greater (RM9088 and RM14516) or comparable (RM10410) cytotoxicity levels compared with EDL933. Comparative pathogenomic analyses revealed that RM9088 harbored numerous genes encoding toxins, toxins delivery systems, and adherence factors, including heat-labile enterotoxin, serine protease autotransporter toxin Pic, type VI secretion systems, protein adhesin Paa, fimbrial adhesin K88, and colonization factor antigen I. RM9088 also harbored a 36-Kb high pathogenicity island, which is related to iron acquisition and pathogenicity in Yersinia spp. Strain RM14516 carried an acid fitness island like the one in EDL933, containing a nine gene cluster involved in iron acquisition. Genes encoding extracellular serine protease EspP, subtilase cytotoxin, F1C fimbriae, and inverse autotransporter adhesin IatC were only detected in RM14516, and genes encoding serine protease autotransporter EspI and P fimbriae were only identified in RM10410. Although all curli genes were present in avian STEC strains, production of curli fimbriae was only detected for RM9088 and RM14516. Consistently, strong, moderate, and little biofilms were observed for RM9088, RM14516, and RM10410, respectively. Our study revealed novel combinations of virulence factors in two avian strains, which exhibited high level of cytotoxicity and strong biofilm formation. Comparative pathogenomics is powerful in assessing pathogenicity and health risk of STEC strains.
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Affiliation(s)
- Michelle Qiu Carter
- Produce Safety and Microbiology Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
| | - Beatriz Quiñones
- Produce Safety and Microbiology Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
| | - Nicole Laniohan
- Produce Safety and Microbiology Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
| | - Diana Carychao
- Produce Safety and Microbiology Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
| | - Antares Pham
- Produce Safety and Microbiology Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
| | - Xiaohua He
- Foodborne Toxin Detection and Prevention Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
| | - Michael Cooley
- Produce Safety and Microbiology Research Unit, U.S. Department of Agriculture, Agricultural Research Service, Western Regional Research Center, Albany, CA, United States
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Elshimy R, Zedan H, Elmorsy TH, Khattab RA. Prevalence and In Vivo Assessment of Virulence in Shiga Toxin-Producing Escherichia coli Clinical Isolates from Greater Cairo Area. Microb Drug Resist 2023; 29:407-415. [PMID: 37579256 DOI: 10.1089/mdr.2022.0348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/16/2023] Open
Abstract
Background: Shiga toxin-producing Escherichia coli (STEC) has been identified as an important etiologic agent of human disease in Egypt. Aims: To investigate the occurrence and describe the characterization as well as prevalence of STEC in Greater Cairo hospitals as well as molecular characterization of virulence and resistance genes. Methods: Four hundred seventy E. coli clinical isolates were collected from eight hospitals and analyzed by genotypic and phenotypic methods for STEC, followed by histopathological examination and scoring of different organs lesions. Results: The highest proportion of isolates was from urine (151 isolates), whereas the lowest was from splenic drain (3 isolates). In tandem, when serogrouping was performed, 15 serogroups were obtained where the most prevalent was O157 and the least prevalent was O151. All isolates were positive when screened for identity gene gad A, while only typable strains were screened for seven virulence genes stx1 (gene encoding Shiga toxin 1), stx2 (gene encoding Shiga toxin 2), tsh (gene encoding thermostable hemagglutinin), eaeA (gene encoding intimin), invE (gene encoding invasion protein), aggR (gene encoding aggregative adherence transcriptional regulator), and astA (aspartate transaminase) where the prevalence was 48%, 30%, 50%, 57%, 7.5%, 12%, and 58%, respectively. Of 254 typable isolates, 152 were STEC carrying stx1 or stx2 genes or both. Conclusions: Relying on in vivo comparison between different E. coli pathotypes via histopathological examination of different organs, E. coli pathotypes could be divided into mild virulent, moderate virulent, and high virulent strains. Statistical analysis revealed significant correlation between different serogroups and presence of virulence genes.
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Affiliation(s)
- Rana Elshimy
- Department of Microbiology and Immunology, Egyptian Drug Authority, Giza, Egypt
- Department of Microbiology and Immunology, Faculty of Pharmacy, Ahram Canadian University, 6th of October City, Egypt
| | - Hamdallah Zedan
- Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo, Egypt
| | - Tarek H Elmorsy
- Department of Microbiology and Immunology, Egyptian Drug Authority, Giza, Egypt
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Okuno M, Tsuru N, Yoshino S, Gotoh Y, Yamamoto T, Hayashi T, Ogura Y. Isolation and Genomic Characterization of a Heat-Labile Enterotoxin 1-Producing Escherichia fergusonii Strain from a Human. Microbiol Spectr 2023; 11:e0049123. [PMID: 37432125 PMCID: PMC10434266 DOI: 10.1128/spectrum.00491-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 06/23/2023] [Indexed: 07/12/2023] Open
Abstract
Escherichia fergusonii strains have been isolated from patients with diarrhea, but their virulence determinant has not been well elucidated. Here, we report the first isolation of a heat-labile enterotoxin 1 (LT1)-producing E. fergusonii strain (strain 30038) from a patient in Japan. The complete genome sequence of strain 30038 was determined and subjected to comparative genomics and phylogenetic analyses with 195 publicly available genomes of E. fergusonii. In addition to strain 30038, the elt1 gene was also identified in an E. fergusonii strain that is phylogenetically distinct and which was isolated from poultry in the United Kingdom. Fine genomic comparison revealed that these two strains share comparable elt1-bearing plasmids. However, an intriguing distinction arises in strain 30038, wherein the plasmid has integrated into the chromosome via a recombination process mediated by an insertion sequence. The production of active LT1 toxin by strain 30038 was verified through an in vitro assay using cultured cells. A large plasmid carrying 11 antimicrobial resistance genes was also identified in strain 30038. Our results indicate that extensive surveillance of elt1-positive E. fergusonii strains as diarrheagenic pathogens is needed. IMPORTANCE Escherichia fergusonii, a species closely related to Escherichia coli, is known to cause sporadic conditions in humans, including diarrhea. However, the critical virulence factors in E. fergusonii clinical isolates remain to be identified. This study shows the first isolation of an E. fergusonii strain carrying the elt1 gene, which encodes heat-labile enterotoxin 1, from a patient with diarrhea. Our analysis of public databases also revealed the presence of elt1-positive E. fergusonii strains isolated from poultry in the United Kingdom. Interestingly, while the elt1 gene in the poultry isolate was present on a large plasmid, in the human isolate it was integrated into the chromosome, which may confer stability on the elt1-carrying genetic element. Our findings highlight the need for extensive surveillance of elt1-positive E. fergusonii strains in livestock animals.
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Affiliation(s)
- Miki Okuno
- Division of Microbiology, Department of Infectious Medicine, Kurume University School of Medicine, Kurume, Japan
| | - Nami Tsuru
- Miyazaki Prefectural Institute for Public Health and Environment, Miyazaki, Japan
| | - Shuji Yoshino
- Miyazaki Prefectural Institute for Public Health and Environment, Miyazaki, Japan
| | - Yasuhiro Gotoh
- Department of Bacteriology, Faculty of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Takeshi Yamamoto
- Division of Microbiology, Department of Infectious Medicine, Kurume University School of Medicine, Kurume, Japan
| | - Tetsuya Hayashi
- Department of Bacteriology, Faculty of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Yoshitoshi Ogura
- Division of Microbiology, Department of Infectious Medicine, Kurume University School of Medicine, Kurume, Japan
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Colello R, Vélez MV, Farias MVN, Rodríguez M, Montero D, Vidal R, Etcheverría AI, Padola NL. Expression of hes, iha, and tpsA codified in locus of adhesion and autoaggregation and their involvement in the capability of shiga toxin-producing Escherichia coli strains to adhere to epithelial cells. BMC Res Notes 2023; 16:163. [PMID: 37550739 PMCID: PMC10408066 DOI: 10.1186/s13104-023-06433-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 07/17/2023] [Indexed: 08/09/2023] Open
Abstract
OBJECTIVES Shiga toxin-producing Escherichia coli strains LAA-positive are important cause of human infection. The capability to adhere to epithelial cells is a key virulence trait, and genes codified in LAA pathogenicity island could be involved in the adhesion during the pathogenesis of LAA-positive STEC strains. Thus, our objectives were to compare hes-negative and hes-positive STEC strains in their adherence capability to epithelial cells (HEp-2) and to evaluate the expression levels of the hes, iha, and tpsA in the bacteria adhered and non-adhered to HEp-2 cells. These genes are encoded in LAA, and are virulence factors that participate in adhesion and autoaggregation. RESULTS We could not observe differences between the adhesion of strains but also in the expression level of of hes, iha, and tpsA. Genes encoded in LAA contribute to the adhesion phenotype though the expression of STEC adhesins is a coordinated event that depends not only the strain but also on the environment as well as its genetic background. Therefore, the results of this study suggest that LAA ,the most prevalent PAI among LEE-negative STEC strains, plays a role in pathogenesis.
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Affiliation(s)
- Rocío Colello
- Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), CISAPA, Tandil, Buenos Aires, 7000, Argentina.
- Centro de Investigación Veterinaria de Tandil (CIVETAN), UNCPBA- CICPBA- CONICET, Tandil, 7000, Argentina.
| | - M Victoria Vélez
- Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), CISAPA, Tandil, Buenos Aires, 7000, Argentina
- Centro de Investigación Veterinaria de Tandil (CIVETAN), UNCPBA- CICPBA- CONICET, Tandil, 7000, Argentina
| | - M Victoria Nieto Farias
- Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), CISAPA, Tandil, Buenos Aires, 7000, Argentina
- Centro de Investigación Veterinaria de Tandil (CIVETAN), UNCPBA- CICPBA- CONICET, Tandil, 7000, Argentina
| | - Marcelo Rodríguez
- Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), SAMP, Tandil, Buenos Aires, 7000, Argentina
| | - David Montero
- Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, 4030555, Chile
- Centro Integrativo de Biología y Química Aplicada (CIBQA), Universidad Bernardo O'Higgins, Santiago, 8320000, Chile
| | - Roberto Vidal
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, 8320000, Chile
| | - Analía I Etcheverría
- Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), CISAPA, Tandil, Buenos Aires, 7000, Argentina
- Centro de Investigación Veterinaria de Tandil (CIVETAN), UNCPBA- CICPBA- CONICET, Tandil, 7000, Argentina
| | - Nora Lía Padola
- Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), CISAPA, Tandil, Buenos Aires, 7000, Argentina
- Centro de Investigación Veterinaria de Tandil (CIVETAN), UNCPBA- CICPBA- CONICET, Tandil, 7000, Argentina
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Milani G, Belloso Daza MV, Cortimiglia C, Bassi D, Cocconcelli PS. Genome engineering of Stx1-and Stx2-converting bacteriophages unveils the virulence of the dairy isolate Escherichia coli O174:H2 strain UC4224. Front Microbiol 2023; 14:1156375. [PMID: 37426006 PMCID: PMC10326431 DOI: 10.3389/fmicb.2023.1156375] [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: 02/01/2023] [Accepted: 06/06/2023] [Indexed: 07/11/2023] Open
Abstract
The past decade witnessed the emergence in Shiga toxin-producing Escherichia coli (STEC) infections linked to the consumption of unpasteurized milk and raw milk cheese. The virulence of STEC is primarily attributed to the presence of Shiga toxin genes (stx1 and stx2) carried by Stx-converting bacteriophages, along with the intimin gene eae. Most of the available information pertains to the "Top 7" serotypes associated with STEC infections. The objectives of this study were to characterize and investigate the pathogenicity potential of E. coli UC4224, a STEC O174:H2 strain isolated from semi-hard raw milk cheese and to develop surrogate strains with reduced virulence for use in food-related studies. Complete genome sequence analysis of E. coli UC4224 unveiled the presence of a Stx1a bacteriophage, a Stx2a bacteriophage, the Locus of Adhesion and Autoaggregation (LAA) pathogenicity island, plasmid-encoded virulence genes, and other colonization facilitators. In the Galleria mellonella animal model, E. coli UC4224 demonstrated high pathogenicity potential with an LD50 of 6 CFU/10 μL. Upon engineering E. coli UC4224 to generate single and double mutant derivatives by inactivating stx1a and/or stx2a genes, the LD50 increased by approximately 1 Log-dose in the single mutants and 2 Log-doses in the double mutants. However, infectivity was not completely abolished, suggesting the involvement of other virulence factors contributing to the pathogenicity of STEC O174:H2. Considering the possibility of raw milk cheese serving as a reservoir for STEC, cheesemaking model was developed to evaluate the survival of UC4224 and the adequacy of the respective mutants as reduced-virulence surrogates. All tested strains exhibited the ability to survive the curd cooking step at 48°C and multiplied (3.4 Log CFU) in cheese within the subsequent 24 h. These findings indicate that genomic engineering did not exert any unintended effect on the double stx1-stx2 mutant behaviour, making it as a suitable less-virulent surrogate for conducting studies during food processing.
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Bonino MP, Crivelli XB, Petrina JF, Galateo S, Gomes TAT, Navarro A, Cundon C, Broglio A, Sanin M, Bentancor A. Detection and analysis of Shiga toxin producing and enteropathogenic Escherichia coli in cattle from Tierra del Fuego, Argentina. Braz J Microbiol 2023; 54:1257-1266. [PMID: 37041346 PMCID: PMC10235289 DOI: 10.1007/s42770-023-00958-8] [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: 12/06/2022] [Accepted: 03/22/2023] [Indexed: 04/13/2023] Open
Abstract
Shiga toxin producing Escherichia coli (STEC) and enteropathogenic E. coli (EPEC) are pathovars that affect mainly infants' health. Cattle are the main reservoir of STEC. Uremic hemolytic syndrome and diarrheas can be found at high rates in Tierra del Fuego (TDF). This study aimed to establish the prevalence of STEC and EPEC in cattle at slaughterhouses in TDF and to analyze the isolated strains. Out of 194 samples from two slaughterhouses, STEC prevalence was 15%, and EPEC prevalence was 5%. Twenty-seven STEC strains and one EPEC were isolated. The most prevalent STEC serotypes were O185:H19 (7), O185:H7 (6), and O178:H19 (5). There were no STEC eae + strains (AE-STEC) or serogroup O157 detected in this study. The prevalent genotype was stx2c (10/27) followed by stx1a/stx2hb (4/27). Fourteen percent of the strains presented at least one stx non-typeable subtype (4/27). Shiga toxin production was detected in 25/27 STEC strains. The prevalent module for the Locus of Adhesion and Autoaggregation (LAA) island was module III (7/27). EPEC strain was categorized as atypical and with the ability to cause A/E lesion. The ehxA gene was present in 16/28 strains, 12 of which were capable of producing hemolysis. No hybrid strains were detected in this work. Antimicrobial susceptibility tests showed that all strains were resistant to ampicillin and 20/28 were resistant to aminoglycosides. No statistical differences could be seen in the detection of STEC or EPEC either by slaughterhouse location or by production system (extensive grass or feedlot). The rate of STEC detection was lower than the one reported for the rest of Argentina. STEC/EPEC relation was 3 to 1. This is the first study on cattle from TDF as reservoir for strains that are potentially pathogenic to humans.
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Affiliation(s)
- Maria Paz Bonino
- Facultad de Ciencias Veterinarias, Universidad de Buenos Aires, Instituto de Investigaciones en Epidemiología Veterinaria, Cátedra de Microbiología, Buenos Aires, Argentina.
- Consejo Nacional de Investigaciones Científicas Y Técnicas (CONICET), Buenos Aires, Argentina.
| | - Ximena Blanco Crivelli
- Facultad de Ciencias Veterinarias, Universidad de Buenos Aires, Instituto de Investigaciones en Epidemiología Veterinaria, Cátedra de Microbiología, Buenos Aires, Argentina
| | - Juan Facundo Petrina
- Departamento de Epidemiología, Ministerio de Salud de Tierra del Fuego, Ushuaia, Argentina
| | - Sebastian Galateo
- Dirección de Fiscalización Sanitaria, Ministerio de Salud de Tierra del Fuego, Ushuaia, Argentina
| | | | - Armando Navarro
- Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional Autónoma de Mexico, Mexico City, Mexico
| | - Cecilia Cundon
- Facultad de Ciencias Veterinarias, Universidad de Buenos Aires, Instituto de Investigaciones en Epidemiología Veterinaria, Cátedra de Microbiología, Buenos Aires, Argentina
| | - Alicia Broglio
- Facultad de Ciencias Veterinarias, Universidad de Buenos Aires, Instituto de Investigaciones en Epidemiología Veterinaria, Cátedra de Microbiología, Buenos Aires, Argentina
- Consejo Nacional de Investigaciones Científicas Y Técnicas (CONICET), Buenos Aires, Argentina
| | - Mariana Sanin
- Facultad de Ciencias Veterinarias, Universidad de Buenos Aires, Instituto de Investigaciones en Epidemiología Veterinaria, Cátedra de Microbiología, Buenos Aires, Argentina
| | - Adriana Bentancor
- Facultad de Ciencias Veterinarias, Universidad de Buenos Aires, Instituto de Investigaciones en Epidemiología Veterinaria, Cátedra de Microbiología, Buenos Aires, Argentina
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Lee W, Kim MH, Sung S, Kim E, An ES, Kim SH, Kim SH, Kim HY. Genome-Based Characterization of Hybrid Shiga Toxin-Producing and Enterotoxigenic Escherichia coli (STEC/ETEC) Strains Isolated in South Korea, 2016-2020. Microorganisms 2023; 11:1285. [PMID: 37317259 DOI: 10.3390/microorganisms11051285] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 05/11/2023] [Accepted: 05/11/2023] [Indexed: 06/16/2023] Open
Abstract
The global emergence of hybrid diarrheagenic E. coli strains incorporating genetic markers from different pathotypes is a public health concern. Hybrids of Shiga toxin-producing and enterotoxigenic E. coli (STEC/ETEC) are associated with diarrhea and hemolytic uremic syndrome (HUS) in humans. In this study, we identified and characterized STEC/ETEC hybrid strains isolated from livestock feces (cattle and pigs) and animal food sources (beef, pork, and meat patties) in South Korea between 2016 and 2020. The strains were positive for genes from STEC and ETEC, such as stx (encodes Shiga toxins, Stxs) and est (encodes heat-stable enterotoxins, ST), respectively. The strains belong to diverse serogroups (O100, O168, O8, O155, O2, O141, O148, and O174) and sequence types (ST446, ST1021, ST21, ST74, ST785, ST670, ST1780, ST1782, ST10, and ST726). Genome-wide phylogenetic analysis revealed that these hybrids were closely related to certain ETEC and STEC strains, implying the potential acquisition of Stx-phage and/or ETEC virulence genes during the emergence of STEC/ETEC hybrids. Particularly, STEC/ETEC strains isolated from livestock feces and animal source foods mostly exhibited close relatedness with ETEC strains. These findings allow further exploration of the pathogenicity and virulence of STEC/ETEC hybrid strains and may serve as a data source for future comparative studies in evolutionary biology.
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Affiliation(s)
- Woojung Lee
- Division of Food Microbiology, National Institute of Food and Drug Safety Evaluation, Ministry of Food and Drug Safety, Cheongju 28159, Republic of Korea
- Institute of Life Sciences & Resources, Department of Food Science and Biotechnology, Kyung Hee University, Yongin 17104, Republic of Korea
| | - Min-Hee Kim
- Division of Food Microbiology, National Institute of Food and Drug Safety Evaluation, Ministry of Food and Drug Safety, Cheongju 28159, Republic of Korea
| | - Soohyun Sung
- Division of Food Microbiology, National Institute of Food and Drug Safety Evaluation, Ministry of Food and Drug Safety, Cheongju 28159, Republic of Korea
| | - Eiseul Kim
- Institute of Life Sciences & Resources, Department of Food Science and Biotechnology, Kyung Hee University, Yongin 17104, Republic of Korea
| | - Eun Sook An
- Division of Food Microbiology, National Institute of Food and Drug Safety Evaluation, Ministry of Food and Drug Safety, Cheongju 28159, Republic of Korea
| | - Seung Hwan Kim
- Division of Food Microbiology, National Institute of Food and Drug Safety Evaluation, Ministry of Food and Drug Safety, Cheongju 28159, Republic of Korea
| | - Soon Han Kim
- Division of Food Microbiology, National Institute of Food and Drug Safety Evaluation, Ministry of Food and Drug Safety, Cheongju 28159, Republic of Korea
| | - Hae-Yeong Kim
- Institute of Life Sciences & Resources, Department of Food Science and Biotechnology, Kyung Hee University, Yongin 17104, Republic of Korea
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Colello R, Baigorri M, Del Canto F, González J, Rogé A, van der Ploeg C, Sánchez Chopa F, Sparo M, Etcheverría A, Padola NL. Occurrence and genetic characterization of Shiga toxin-producing Escherichia coli on bovine and pork carcasses and the environment from transport trucks. World J Microbiol Biotechnol 2023; 39:174. [PMID: 37115263 DOI: 10.1007/s11274-023-03624-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 04/17/2023] [Indexed: 04/29/2023]
Abstract
Shiga toxin-producing Escherichia coli (STEC) are foodborne pathogens causing severe diseases. The ability of STEC to produce disease is associated with Shiga toxin (Stx) production. We investigated the occurrence of STEC on bovine and pork carcasses and walls of trucks where they were transported, and we characterized virulence genes and serotypes of STEC strains. We compared the whole genomic sequencing of a STEC O157:H7 strain isolated from a bovine carcass in this work and a STEC O157:H7 strain isolated from a child with HUS, both isolated in 2019. We studied the relationship between these isolates and others collected in the database. The results show a 40% of STEC and two different serogroups were identified (O130 and O157). STEC O157:H7 were isolated from bovine carcasses and harbored stx2, eae, ehxA, katP, espP, stcE, ECSP_0242/1773/2687/2870/2872/3286/3620 and were classified as lineage I/II. In STEC non-O157 isolates, three isolates were isolated from bovine carcasses and harbored the serogroup O130 and one strain isolated from pork carcasses was O-non-typeable. All STEC non-O157 harbored sxt1 gene. The analysis from the whole genome showed that both STEC O157:H7 strains belonged to the hypervirulent clade 8, ST11, phylogroup E, carried the allele tir 255 T > A T, and they were not clonal. The analysis of information allows us to conclude that the STEC strains circulate in pork and bovine carcasses arriving in transport. This situation represents a risk for the consumers and the need to implement an integrated STEC control in the food chain.
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Affiliation(s)
- Rocío Colello
- Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), Tandil, Buenos Aires, Argentina.
- Centro de Investigación Veterinaria de Tandil (CIVETAN), UNCPBA- CICPBA- CONICET, Tandil, Buenos Aires, Argentina.
| | - Manuela Baigorri
- Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), Tandil, Buenos Aires, Argentina
| | - Felipe Del Canto
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Juliana González
- Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), Tandil, Buenos Aires, Argentina
- Centro de Investigación Veterinaria de Tandil (CIVETAN), UNCPBA- CICPBA- CONICET, Tandil, Buenos Aires, Argentina
| | - Ariel Rogé
- Servicio Antígenos y Antisueros, Instituto Nacional de Producción de Biológicos, Administración Nacional de Laboratorios e Institutos de Salud "Dr. Carlos G. Malbrán", Buenos Aires, Argentina
| | - Claudia van der Ploeg
- Servicio Antígenos y Antisueros, Instituto Nacional de Producción de Biológicos, Administración Nacional de Laboratorios e Institutos de Salud "Dr. Carlos G. Malbrán", Buenos Aires, Argentina
| | - Federico Sánchez Chopa
- Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), Tandil, Buenos Aires, Argentina
- Centro de Investigación Veterinaria de Tandil (CIVETAN), UNCPBA- CICPBA- CONICET, Tandil, Buenos Aires, Argentina
| | - Mónica Sparo
- Laboratorio de Microbiología Clínica, Hospital Ramón Santamarina, Tandil, Buenos Aires, Argentina
| | - Analía Etcheverría
- Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), Tandil, Buenos Aires, Argentina
- Centro de Investigación Veterinaria de Tandil (CIVETAN), UNCPBA- CICPBA- CONICET, Tandil, Buenos Aires, Argentina
| | - Nora Lía Padola
- Facultad de Ciencias Veterinarias, Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), Tandil, Buenos Aires, Argentina
- Centro de Investigación Veterinaria de Tandil (CIVETAN), UNCPBA- CICPBA- CONICET, Tandil, Buenos Aires, Argentina
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15
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Safety and Immunogenicity of a Chimeric Subunit Vaccine against Shiga Toxin-Producing Escherichia coli in Pregnant Cows. Int J Mol Sci 2023; 24:ijms24032771. [PMID: 36769094 PMCID: PMC9917558 DOI: 10.3390/ijms24032771] [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: 12/12/2022] [Revised: 01/21/2023] [Accepted: 01/24/2023] [Indexed: 02/04/2023] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) is a zoonotic pathogen that causes gastroenteritis and Hemolytic Uremic Syndrome. Cattle are the main animal reservoir, excreting the bacteria in their feces and contaminating the environment. In addition, meat can be contaminated by releasing the intestinal content during slaughtering. Here, we evaluated the safety and immunogenicity of a vaccine candidate against STEC that was formulated with two chimeric proteins (Chi1 and Chi2), which contain epitopes of the OmpT, Cah and Hes proteins. Thirty pregnant cows in their third trimester of gestation were included and distributed into six groups (n = 5 per group): four groups were administered intramuscularly with three doses of the formulation containing 40 µg or 100 µg of each protein plus the Quil-A or Montanide™ Gel adjuvants, while two control groups were administered with placebos. No local or systemic adverse effects were observed during the study, and hematological parameters and values of blood biochemical indicators were similar among all groups. Furthermore, all vaccine formulations triggered systemic anti-Chi1/Chi2 IgG antibody levels that were significantly higher than the control groups. However, specific IgA levels were generally low and without significant differences among groups. Notably, anti-Chi1/Chi2 IgG antibody levels in the serum of newborn calves fed with colostrum from their immunized dams were significantly higher compared to newborn calves fed with colostrum from control cows, suggesting a passive immunization through colostrum. These results demonstrate that this vaccine is safe and immunogenic when applied to pregnant cows during the third trimester of gestation.
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Vélez MV, Colello R, Etcheverría AI, Padola NL. [Shiga toxin producing Escherichia coli: the challenge of adherence to survive]. Rev Argent Microbiol 2023; 55:100-107. [PMID: 35676186 DOI: 10.1016/j.ram.2022.04.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 11/05/2021] [Accepted: 04/19/2022] [Indexed: 10/18/2022] Open
Abstract
Shiga Toxin-producing Escherichia coli (STEC) is recognized as being responsible for a large number of foodborne illnesses around the world. The pathogenicity of STEC has been related to Stx toxins. However, the ability of STEC to colonize the host and other surfaces can be essential for developing its pathogenicity. Different virulence profiles detected in STEC could cause the emergence of strains carrying new genes codified in new pathogenicity islands linked to metabolism and adherence. Biofilm formation is a spontaneous mechanism whereby STEC strains resist in a hostile environment being able to survive and consequently infect the host through contaminated food and food contact surfaces. Biofilm formation shows intra-and inter-serotype variability, and its formation does not depend only on the microorganisms involved. Other factors related to the environment (such as pH, temperature) and the surface (stainless steel and polystyrene) influence biofilm expression. The «One Health» concept implies the interrelation between public, animal, and environmental health actors to ensure food safety, prevent cross-contamination and resistance to sanitizers, highlighting the need to identify emerging pathogens through new molecular markers of rapid detection that involve STEC strains carrying the Locus of Enterocyte Effacement or Locus of Adhesion and Autoaggregation.
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Affiliation(s)
- M V Vélez
- Laboratorio de Inmunoquímica y Biotecnología, Facultad de Ciencias Veterinarias, CIVETAN-CONICET-CIC-UNCPBA, Tandil, Argentina
| | - R Colello
- Laboratorio de Inmunoquímica y Biotecnología, Facultad de Ciencias Veterinarias, CIVETAN-CONICET-CIC-UNCPBA, Tandil, Argentina
| | - A I Etcheverría
- Laboratorio de Inmunoquímica y Biotecnología, Facultad de Ciencias Veterinarias, CIVETAN-CONICET-CIC-UNCPBA, Tandil, Argentina
| | - N L Padola
- Laboratorio de Inmunoquímica y Biotecnología, Facultad de Ciencias Veterinarias, CIVETAN-CONICET-CIC-UNCPBA, Tandil, Argentina.
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Mussio P, Martínez I, Luzardo S, Navarro A, Leotta G, Varela G. Phenotypic and genotypic characterization of Shiga toxin-producing Escherichia coli strains recovered from bovine carcasses in Uruguay. Front Microbiol 2023; 14:1130170. [PMID: 36950166 PMCID: PMC10025531 DOI: 10.3389/fmicb.2023.1130170] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 02/13/2023] [Indexed: 03/08/2023] Open
Abstract
Introduction Shiga toxin-producing Escherichia coli (STEC) is a zoonotic pathogen that cause food-borne diseases in humans. Cattle and derived foodstuffs play a known role as reservoir and vehicles, respectively. In Uruguay, information about the characteristics of circulating STEC in meat productive chain is scarce. The aim was to characterize STEC strains recovered from 800 bovine carcasses of different slaughterhouses. Methods To characterize STEC strains we use classical microbiological procedures, Whole Genome Sequencing (WGS) and FAO/WHO risk criteria. Results We analyzed 39 STEC isolated from 20 establishments. They belonged to 21 different O-groups and 13 different H-types. Only one O157:H7 strain was characterized and the serotypes O130:H11(6), O174:H28(5), and O22:H8(5) prevailed. One strain showed resistance in vitro to tetracycline and genes for doxycycline, sulfonamide, streptomycin and fosfomycin resistance were detected. Thirty-three strains (84.6%) carried the subtypes Stx2a, Stx2c, or Stx2d. The gene eae was detected only in two strains (O157:H7, O182:H25). The most prevalent virulence genes found were lpfA (n = 38), ompA (n = 39), ompT (n = 39), iss (n = 38), and terC (n = 39). Within the set of STEC analyzed, the majority (81.5%) belonged to FAO/WHO's risk classification levels 4 and 5 (lower risk). Besides, we detected STEC serotypes O22:H8, O113:H21, O130:H11, and O174:H21 belonged to level risk 2 associate with diarrhea, hemorrhagic colitis or Hemolytic-Uremic Syndrome (HUS). The only O157:H7 strain analyzed belonged to ST11. Thirty-eight isolates belonged to the Clermont type B1, while the O157:H7 was classified as E. Discussion The analyzed STEC showed high genomic diversity and harbor several genetic determinants associated with virulence, underlining the important role of WGS for a complete typing. In this set we did not detect non-O157 STEC previously isolated from local HUS cases. However, when interpreting this findings, the low number of isolates analyzed and some methodological limitations must be taken into account. Obtained data suggest that cattle constitute a local reservoir of non-O157 serotypes associated with severe diseases. Other studies are needed to assess the role of the local meat chain in the spread of STEC, especially those associated with severe diseases in humans.
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Affiliation(s)
- Paula Mussio
- Departamento de Microbiología, Laboratorio Tecnológico del Uruguay, Montevideo, Uruguay
- *Correspondence: Paula Mussio,
| | | | - Santiago Luzardo
- Instituto Nacional de Investigación Agropecuaria, INIA, Tacuarembó, Uruguay
| | - Armando Navarro
- Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Gerardo Leotta
- Instituto de Ciencia y Tecnología de Sistemas Alimentarios Sustentables, UEDD INTA-CONICET, Buenos Aires, Argentina
| | - Gustavo Varela
- Departamento de Bacteriología y Virología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
- Gustavo Varela,
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Carter MQ, Laniohan N, Pham A, Quiñones B. Comparative genomic and phenotypic analyses of the virulence potential in Shiga toxin-producing Escherichia coli O121:H7 and O121:H10. Front Cell Infect Microbiol 2022; 12:1043726. [PMID: 36506028 PMCID: PMC9729726 DOI: 10.3389/fcimb.2022.1043726] [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: 09/13/2022] [Accepted: 11/03/2022] [Indexed: 11/25/2022] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) O121 is among the top six non-O157 serogroups that are most frequently associated with severe disease in humans. While O121:H19 is predominant, other O121 serotypes have been frequently isolated from environmental samples, but their virulence repertoire is poorly characterized. Here, we sequenced the complete genomes of two animal isolates belonging to O121:H7 and O121:H10 and performed comparative genomic analysis with O121:H19 to assess their virulence potential. Both O121:H7 and O121:H10 strains carry a genome comparable in size with the O121:H19 genomes and belong to phylogroup B1. However, both strains appear to have evolved from a different lineage than the O121:H19 strains according to the core genes-based phylogeny and Multi Locus Sequence Typing. A systematic search of over 300 E. coli virulence genes listed in the Virulence Factor DataBase revealed a total of 73 and 71 in O121:H7 and O121:H10 strains, respectively, in comparison with an average of 135 in the O121:H19 strains. This variation in the virulence genes repertoire was mainly attributed to the reduction in the number of genes related to the Type III Secretion System in the O121:H7 and O121:H10 strains. Compared to the O121:H19 strains, the O121:H7 strain carries more adherence and toxin genes while the O121:H10 strain carries more genes related to the Type VI Secretion System. Although both O121:H7 and O121:H10 strains carry the large virulence plasmid pEHEC, they do not harbor all pEHEC virulence genes in O121:H19. Furthermore, unlike the O121:H19 strains, neither the O121:H7 nor O121:H10 strain carried the Locus of Enterocyte Effacement, OI-122, nor the tellurite resistance island. Although an incomplete Locus of Adhesion and Autoaggregation (LAA) was identified in the O121:H7 and O121:H10 strains, a limited number of virulence genes were present. Consistently, both O121:H7 and O121:H10 strains displayed significant reduced cytotoxicity than either the O157:H7 strain EDL933 or the O121:H19 strain RM8352. In fact, the O121:H7 strain RM8082 appeared to cause minimal cytotoxicity to Vero cells. Our study demonstrated distinct evolutionary lineages among the strains of serotypes O121:H19, O121:H10, and O121:H7 and suggested reduced virulence potentials in STEC strains of O121:H10 and O121:H7.
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Ray R, Singh P. Prevalence and Implications of Shiga Toxin-Producing E. coli in Farm and Wild Ruminants. Pathogens 2022; 11:1332. [PMID: 36422584 PMCID: PMC9694250 DOI: 10.3390/pathogens11111332] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 11/04/2022] [Accepted: 11/08/2022] [Indexed: 08/27/2023] Open
Abstract
Shiga-toxin-producing Escherichia coli (STEC) is a food-borne pathogen that causes human gastrointestinal infections across the globe, leading to kidney failure or even death in severe cases. E. coli are commensal members of humans and animals' (cattle, bison, and pigs) guts, however, may acquire Shiga-toxin-encoded phages. This acquisition or colonization by STEC may lead to dysbiosis in the intestinal microbial community of the host. Wildlife and livestock animals can be asymptomatically colonized by STEC, leading to pathogen shedding and transmission. Furthermore, there has been a steady uptick in new STEC variants representing various serotypes. These, along with hybrids of other pathogenic E. coli (UPEC and ExPEC), are of serious concern, especially when they possess enhanced antimicrobial resistance, biofilm formation, etc. Recent studies have reported these in the livestock and food industry with minimal focus on wildlife. Disturbed natural habitats and changing climates are increasingly creating wildlife reservoirs of these pathogens, leading to a rise in zoonotic infections. Therefore, this review comprehensively surveyed studies on STEC prevalence in livestock and wildlife hosts. We further present important microbial and environmental factors contributing to STEC spread as well as infections. Finally, we delve into potential strategies for limiting STEC shedding and transmission.
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Affiliation(s)
| | - Pallavi Singh
- Department of Biological Sciences, Northern Illinois University, Dekalb, IL 60115, USA
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20
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Whole-genome sequencing analysis of Shiga toxin-producing Escherichia coli O22:H8 isolated from cattle prediction pathogenesis and colonization factors and position in STEC universe phylogeny. J Microbiol 2022; 60:689-704. [DOI: 10.1007/s12275-022-1616-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 02/25/2022] [Accepted: 03/24/2022] [Indexed: 10/17/2022]
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Liu Y, Xu T, Wang Q, Huang J, Zhu Y, Liu X, Liu R, Yang B, Zhou K. Vibrio cholerae senses human enteric α-defensin 5 through a CarSR two-component system to promote bacterial pathogenicity. Commun Biol 2022; 5:559. [PMID: 35676416 PMCID: PMC9178039 DOI: 10.1038/s42003-022-03525-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 05/23/2022] [Indexed: 11/09/2022] Open
Abstract
Vibrio cholerae (V. cholerae) is an aquatic bacterium responsible for acute and fatal cholera outbreaks worldwide. When V. cholerae is ingested, the bacteria colonize the epithelium of the small intestine and stimulate the Paneth cells to produce large amounts of cationic antimicrobial peptides (CAMPs). Human defensin 5 (HD-5) is the most abundant CAMPs in the small intestine. However, the role of the V. cholerae response to HD-5 remains unclear. Here we show that HD-5 significantly upregulates virulence gene expression. Moreover, a two-component system, CarSR (or RstAB), is essential for V. cholerae virulence gene expression in the presence of HD-5. Finally, phosphorylated CarR can directly bind to the promoter region of TcpP, activating transcription of tcpP, which in turn activates downstream virulence genes to promote V. cholerae colonization. In conclusion, this study reveals a virulence-regulating pathway, in which the CarSR two-component regulatory system senses HD-5 to activate virulence genes expression in V. cholerae.
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Affiliation(s)
- Yutao Liu
- TEDA Institute of Biological Sciences and Biotechnology, TEDA, Nankai University, Tianjin, PR China
| | - Tingting Xu
- The Second Clinical Medical College, Jinan University, The First Affiliated Hospital, Southern University of Science and Technology, Shenzhen People's Hospital, Shenzhen Institute of Respiratory Diseases, Shenzhen, Guangdong, PR China
| | - Qian Wang
- TEDA Institute of Biological Sciences and Biotechnology, TEDA, Nankai University, Tianjin, PR China
| | - Junxi Huang
- The Second Clinical Medical College, Jinan University, The First Affiliated Hospital, Southern University of Science and Technology, Shenzhen People's Hospital, Shenzhen Institute of Respiratory Diseases, Shenzhen, Guangdong, PR China
| | - Yangfei Zhu
- The Second Clinical Medical College, Jinan University, The First Affiliated Hospital, Southern University of Science and Technology, Laboratory Department, Shenzhen People's Hospital, Shenzhen, Guangdong, PR China
| | - Xingmei Liu
- TEDA Institute of Biological Sciences and Biotechnology, TEDA, Nankai University, Tianjin, PR China
| | - Ruiying Liu
- TEDA Institute of Biological Sciences and Biotechnology, TEDA, Nankai University, Tianjin, PR China
| | - Bin Yang
- TEDA Institute of Biological Sciences and Biotechnology, TEDA, Nankai University, Tianjin, PR China.
| | - Kai Zhou
- The Second Clinical Medical College, Jinan University, The First Affiliated Hospital, Southern University of Science and Technology, Shenzhen People's Hospital, Shenzhen Institute of Respiratory Diseases, Shenzhen, Guangdong, PR China.
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Comparative Genomics Applied to Systematically Assess Pathogenicity Potential in Shiga Toxin-Producing Escherichia coli O145:H28. Microorganisms 2022; 10:microorganisms10050866. [PMID: 35630311 PMCID: PMC9144400 DOI: 10.3390/microorganisms10050866] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 04/14/2022] [Accepted: 04/19/2022] [Indexed: 01/27/2023] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) O145:H28 can cause severe disease in humans and is a predominant serotype in STEC O145 environmental isolates. Here, comparative genomics was applied to a set of clinical and environmental strains to systematically evaluate the pathogenicity potential in environmental strains. While the core genes-based tree separated all O145:H28 strains from the non O145:H28 reference strains, it failed to segregate environmental strains from the clinical. In contrast, the accessory genes-based tree placed all clinical strains in the same clade regardless of their genotypes or serotypes, apart from the environmental strains. Loss-of-function mutations were common in the virulence genes examined, with a high frequency in genes related to adherence, autotransporters, and the type three secretion system. Distinct differences in pathogenicity islands LEE, OI-122, and OI-57, the acid fitness island, and the tellurite resistance island were detected between the O145:H28 and reference strains. A great amount of genetic variation was detected in O145:H28, which was mainly attributed to deletions, insertions, and gene acquisition at several chromosomal “hot spots”. Our study demonstrated a distinct virulence gene repertoire among the STEC O145:H28 strains originating from the same geographical region and revealed unforeseen contributions of loss-of-function mutations to virulence evolution and genetic diversification in STEC.
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Characterisation of atypical Shiga toxin gene sequences and description of Stx2j, a new subtype. J Clin Microbiol 2022; 60:e0222921. [PMID: 35225693 DOI: 10.1128/jcm.02229-21] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Shiga toxin (Stx) is the definitive virulence factor of Shiga toxin-producing Escherichia coli (STEC). Stx variants are currently organised into a taxonomic system of three Stx1 (a,c,d) and seven Stx2 (a,b,c,d,e,f,g) subtypes. In this study, seven STEC isolates from food and clinical samples possessing stx2 sequences that do not fit current Shiga toxin taxonomy were identified. Genome assemblies of the STEC strains was created from Oxford Nanopore and Illumina sequence data. The presence of atypical stx2 sequences were confirmed by Sanger sequencing, as were Stx2 expression and cytotoxicity. A strain of O157:H7 was found to possess stx1a and a truncated stx2a, which were originally misidentified as an atypical stx2. Two strains possessed unreported variants of Stx2a (O8:H28) and Stx2b (O146:H21). In four of the strains we found three Stx-subtypes that are not included in the current taxonomy. Stx2h (O170:H18) was identified in a Canadian sprout isolate; this subtype has only previously been reported in STEC from Tibetan Marmots. Stx2o (O85:H1) was identified in a clinical isolate. Finally, Stx2j (O158:H23 and O33:H14) was found in lettuce and clinical isolates. The results of this study expands the number of known Stx subtypes, the range of STEC serotypes, and isolation sources in which they may be found. The presence of the Stx2j and Stx2o in clinical isolates of STEC indicates that strains carrying these variants are potential human pathogens. Highlights Atypical Shiga toxin (stx) genes in Escherichia coli were sequenced. Two new variants of stx2a and stx2b are described. Two strains carried subtypes Stx2h and Stx2o, which have only one previous report. Two strains carried a previously undescribed subtype, Stx2j.
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Hermansen S, Linke D, Leo JC. Transmembrane β-barrel proteins of bacteria: From structure to function. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2022; 128:113-161. [PMID: 35034717 DOI: 10.1016/bs.apcsb.2021.07.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The outer membrane of Gram-negative bacteria is a specialized organelle conferring protection to the cell against various environmental stresses and resistance to many harmful compounds. The outer membrane has a number of unique features, including an asymmetric lipid bilayer, the presence of lipopolysaccharides and an individual proteome. The vast majority of the integral transmembrane proteins in the outer membrane belongs to the family of β-barrel proteins. These evolutionarily related proteins share a cylindrical, anti-parallel β-sheet core fold spanning the outer membrane. The loops and accessory domains attached to the β-barrel allow for a remarkable versatility in function for these proteins, ranging from diffusion pores and transporters to enzymes and adhesins. We summarize the current knowledge on β-barrel structure and folding and give an overview of their functions, evolution, and potential as drug targets.
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Affiliation(s)
- Simen Hermansen
- Section for Genetics and Evolutionary Biology, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Dirk Linke
- Section for Genetics and Evolutionary Biology, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Jack C Leo
- Antimicrobial resistance, Omics and Microbiota Group, Department of Biosciences, Nottingham Trent University, Nottingham, United Kingdom.
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Distribution of virulence factors, antimicrobial resistance genes and phylogenetic relatedness among Shiga toxin-producing Escherichia coli serogroup O91 from human infections. Int J Med Microbiol 2021; 311:151541. [PMID: 34757276 DOI: 10.1016/j.ijmm.2021.151541] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 10/10/2021] [Accepted: 10/25/2021] [Indexed: 12/18/2022] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) belonging to the serogroup O91 are among the most common non-O157 STEC serogroups associated with human illness in Europe. This study aimed to analyse the virulence factors, antimicrobial resistance genes and phylogenetic relatedness among 48 clinical STEC O91 isolates collected during 2003-2019 in Switzerland. The isolates were subjected to whole genome sequencing using short-read sequencing technologies and a subset of isolates additionally to long-read sequencing. They belonged to O91:H10 (n=6), O91:H14 (n=40), and O91:H21 (n=2). Multilocus sequence typing showed that the O91:H10 isolates all belonged to sequence type (ST)641, while the O91:H14 isolates were assigned to ST33, ST9700, or were non-typeable. Both O91:H21 isolates belonged to ST442. Shiga toxin gene stx1a was the most common Shiga toxin gene subtype among the isolates, followed by stx2b, stx2d and stx2a. All isolates were LEE-negative and carried one or two copies of the IrgA adhesin gene iha. In a subset of long-read sequenced isolates, modules of the Locus of Adhesion and Autoaggregation pathogenicity island (LAA-PAI) carrying iha and other genes such as hes, lesP or agn43 were identified. A large proportion of STEC O91:H14 carried the subtilase cytotoxin gene subA, colicin genes (cba, cea, cib and cma) or microcin genes (mcmA, mchB, mchC and mchF). STEC O91:H14 were further distinguished from STEC O91:H10/H21 by one or more virulence factors found in extraintestinal pathogenic E. coli (ExPEC), including hlyF, iucC/iutA, kpsE and traT. The hlyF gene was identified on a novel mosaic plasmid that was unrelated to hlyF+ plasmids described previously in STEC. Core genome phylogenetic analysis revealed that STEC O91:H10 and STEC O91:H21 were clonally conserved, whereas STEC O91:H14 were clonally diverse. Among three STEC O91:H14 isolates, a number of resistance genes were identified, including genes that mediate resistance to aminoglycosides (aadA, aadA2, aadA9, aadA23, aph(3'')-Ib and aph(6)-Id), chloramphenicol (cmlA), sulphonamides (sul2 and sul3), and trimethoprim (drfA12). Our data contribute to understanding the genetic diversity and differing levels of virulence potential within the STEC O91 serogroup.
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Potential Zoonotic Pathovars of Diarrheagenic Escherichia coli Detected in Lambs for Human Consumption from Tierra del Fuego, Argentina. Microorganisms 2021; 9:microorganisms9081710. [PMID: 34442790 PMCID: PMC8401499 DOI: 10.3390/microorganisms9081710] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Revised: 08/01/2021] [Accepted: 08/03/2021] [Indexed: 01/03/2023] Open
Abstract
Diarrheagenic Escherichia coli (DEC) pathovars impact childhood health. The southern region of Argentina shows the highest incidence of hemolytic uremic syndrome (HUS) in children of the country. The big island of Tierra del Fuego (TDF) in Argentina registered an incidence of five cases/100,000 inhabitants of HUS in 2019. This work aimed to establish the prevalence of STEC, EPEC, and EAEC in lambs slaughtered in abattoirs from TDF as well as to characterize the phenotypes and the genotypes of the isolated pathogens. The prevalence was 26.6% for stx+, 5.7% for eae+, and 0.27% for aagR+/aaiC+. Twelve STEC isolates were obtained and belonged to the following serotypes: O70:HNT, O81:H21, O81:HNT, O102:H6, O128ab:H2, O174:H8, and O174:HNT. Their genotypic profiles were stx1c (2), stx1c/ehxA (3), stx2b/ehxA (1), stx1c/stx2b (2), and stx1c/stx2/ehxA (4). Six EPEC isolates were obtained and corresponded to five serotypes: O2:H40, O32:H8, O56:H6, O108:H21, and O177:H25. All the EPEC isolates were bfpA- and two were ehxA+. By XbaI-PFGE of 17 isolates, two clusters were identified. By antimicrobial susceptibility tests, 8/12 STEC and 5/6 EPEC were resistant to at least one antibiotic. This work provides new data to understand the ecology of DEC in TDF and confirms that ovine are an important carrier of these pathogens in the region.
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Galarce N, Sánchez F, Escobar B, Lapierre L, Cornejo J, Alegría-Morán R, Neira V, Martínez V, Johnson T, Fuentes-Castillo D, Sano E, Lincopan N. Genomic Epidemiology of Shiga Toxin-Producing Escherichia coli Isolated from the Livestock-Food-Human Interface in South America. Animals (Basel) 2021; 11:ani11071845. [PMID: 34206206 PMCID: PMC8300192 DOI: 10.3390/ani11071845] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 06/15/2021] [Accepted: 06/16/2021] [Indexed: 12/20/2022] Open
Abstract
Simple Summary Shiga toxin-producing Escherichia coli (STEC) are zoonotic pathogens that cause food-borne diseases in humans, where cattle and derived products play a key role as reservoirs and vehicles. We analyzed the genomic data of STEC strains circulating at the livestock-food-human interface in South America, extracting clinically and epidemiologically relevant information (serotypes, virulome, resistance genes, sequence types, and phylogenomics). This study included 130 STEC genomes obtained from cattle (n = 51), beef (n = 48), and human (n = 31) samples. The successful expansion of O157:H7 (ST11) and non-O157 (ST16, ST21, ST223, ST443, ST677, ST679, ST2388) clones is highlighted, suggesting common activities, such as multilateral trade and travel. Circulating STEC strains analyzed exhibit high genomic diversity and harbor several genetic determinants associated with severe illness in humans, highlighting the need to establish official surveillance of this pathogen that should be focused on detecting molecular determinants of virulence and clonal relatedness, in the whole beef production chain. Abstract Shiga toxin-producing Escherichia coli (STEC) are zoonotic pathogens responsible for causing food-borne diseases in humans. While South America has the highest incidence of human STEC infections, information about the genomic characteristics of the circulating strains is scarce. The aim of this study was to analyze genomic data of STEC strains isolated in South America from cattle, beef, and humans; predicting the antibiotic resistome, serotypes, sequence types (STs), clonal complexes (CCs) and phylogenomic backgrounds. A total of 130 whole genome sequences of STEC strains were analyzed, where 39.2% were isolated from cattle, 36.9% from beef, and 23.8% from humans. The ST11 was the most predicted (20.8%) and included O-:H7 (10.8%) and O157:H7 (10%) serotypes. The successful expansion of non-O157 clones such as ST16/CC29-O111:H8 and ST21/CC29-O26:H11 is highlighted, suggesting multilateral trade and travel. Virulome analyses showed that the predominant stx subtype was stx2a (54.6%); most strains carried ehaA (96.2%), iha (91.5%) and lpfA (77.7%) genes. We present genomic data that can be used to support the surveillance of STEC strains circulating at the livestock-food-human interface in South America, in order to control the spread of critical clones “from farm to table”.
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Affiliation(s)
- Nicolás Galarce
- Departamento de Medicina Preventiva Animal, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago 8820808, Chile; (F.S.); (B.E.); (L.L.); (J.C.); (R.A.-M.); (V.N.)
- Correspondence:
| | - Fernando Sánchez
- Departamento de Medicina Preventiva Animal, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago 8820808, Chile; (F.S.); (B.E.); (L.L.); (J.C.); (R.A.-M.); (V.N.)
- Programa de Doctorado en Ciencias Silvoagropecuarias y Veterinarias, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago 8820808, Chile
| | - Beatriz Escobar
- Departamento de Medicina Preventiva Animal, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago 8820808, Chile; (F.S.); (B.E.); (L.L.); (J.C.); (R.A.-M.); (V.N.)
| | - Lisette Lapierre
- Departamento de Medicina Preventiva Animal, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago 8820808, Chile; (F.S.); (B.E.); (L.L.); (J.C.); (R.A.-M.); (V.N.)
| | - Javiera Cornejo
- Departamento de Medicina Preventiva Animal, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago 8820808, Chile; (F.S.); (B.E.); (L.L.); (J.C.); (R.A.-M.); (V.N.)
| | - Raúl Alegría-Morán
- Departamento de Medicina Preventiva Animal, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago 8820808, Chile; (F.S.); (B.E.); (L.L.); (J.C.); (R.A.-M.); (V.N.)
- Facultad de Ciencias Agropecuarias y Ambientales, Universidad Pedro de Valdivia, Santiago 8370007, Chile
| | - Víctor Neira
- Departamento de Medicina Preventiva Animal, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago 8820808, Chile; (F.S.); (B.E.); (L.L.); (J.C.); (R.A.-M.); (V.N.)
| | - Víctor Martínez
- Departamento de Fomento de la Producción Animal, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago 8820808, Chile;
| | - Timothy Johnson
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, USA;
| | - Danny Fuentes-Castillo
- Departamento de Patología, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo 05508-270, Brazil;
| | - Elder Sano
- Departamento de Microbiología, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo 05508-900, Brazil; (E.S.); (N.L.)
| | - Nilton Lincopan
- Departamento de Microbiología, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo 05508-900, Brazil; (E.S.); (N.L.)
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Victoria VM, Rocío C, Silvina E, Inés EA, Lía PN. Biofilm formation by LEE-negative Shiga Toxin-Producing Escherichia coli strains. Microb Pathog 2021; 157:105006. [PMID: 34044049 DOI: 10.1016/j.micpath.2021.105006] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 03/31/2021] [Accepted: 04/01/2021] [Indexed: 11/27/2022]
Abstract
Shiga toxin-producing Escherichia coli (STEC) include several serotypes isolated from cases of hemorrhagic colitis and, hemolytic uremic syndrome. Although O157:H7 is the most predominant STEC serotype, more than 100 non-O157 serogroups cause diseases in humans. Some STEC carry a Locus of Enterocyte Effacement (LEE-positive); however, STEC that do not carry LEE (LEE-negative) have also been associated with illness, mainly those harbouring the Locus of Adhesion and Autoaggregation (LAA). LAA carry some genes such as hes, iha, tpsA, and agn43, related with pathogenicity. One of them is the ability to form biofilms on different environments, which can contaminate food and generate infections while protecting themselves against adverse conditions. Considering that LAA could be responsible for some adherence mechanisms, the aims of this study were to compare different serogroup of LEE-negative STEC strains in their ability to form biofilms and to evaluate the participation of some genes encoding in LAA. A total of 348 LEE-negative STEC strains was analyzed. The presence of hes, iha, tpsA and agn43 were determined by monoplex PCR. From them, 48 STEC strains belonging to serogroups O113, O130, O171, O174 and, O178 were assayed for their ability to form biofilm. The most prevalent genes detected were agn43 (72.1%) and tpsA (69.5%). The iha and hes genes were present in 63.7% and 54% of the strains, respectively. Although all STEC strains were able to form biofilm, it was found a high variability between them. The relation between the biofilm formation and the presence of each gene was not statistically significant, suggesting that biofilm formation is independent of the presence of those genes. Highlighting that there is no treatment for HUS, it is once again notable that prevention measures and control strategies to prevent biofilm formation are important factors in reducing STEC transmission.
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Affiliation(s)
- Vélez María Victoria
- Laboratorio de Inmunoquímica y Biotecnología. Centro de Investigación Veterinaria Tandil CONICET- CICPBA, Facultad de Ciencias Veterinarias, UNCPBA CIVETAN. (7000) Tandil, Buenos Aires, Argentina
| | - Colello Rocío
- Laboratorio de Inmunoquímica y Biotecnología. Centro de Investigación Veterinaria Tandil CONICET- CICPBA, Facultad de Ciencias Veterinarias, UNCPBA CIVETAN. (7000) Tandil, Buenos Aires, Argentina.
| | - Etcheverría Silvina
- Cátedra Estadística, Econometría y Modelización. Tandil, Facultad de Ciencias Económicas, UNCPBA. (7000) Tandil, Buenos Aires, Argentina
| | - Etcheverría Analía Inés
- Laboratorio de Inmunoquímica y Biotecnología. Centro de Investigación Veterinaria Tandil CONICET- CICPBA, Facultad de Ciencias Veterinarias, UNCPBA CIVETAN. (7000) Tandil, Buenos Aires, Argentina
| | - Padola Nora Lía
- Laboratorio de Inmunoquímica y Biotecnología. Centro de Investigación Veterinaria Tandil CONICET- CICPBA, Facultad de Ciencias Veterinarias, UNCPBA CIVETAN. (7000) Tandil, Buenos Aires, Argentina
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Eugenol, citral, and hexanal, alone or in combination with heat, affect viability, biofilm formation, and swarming on Shiga-toxin-producing Escherichia coli. Food Sci Biotechnol 2021; 30:599-607. [PMID: 33936852 DOI: 10.1007/s10068-021-00887-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 02/03/2021] [Accepted: 02/05/2021] [Indexed: 10/21/2022] Open
Abstract
Shiga-toxin-producing Escherichia coli strains are pathogenic for humans and cause mild to severe illnesses. In this study, the antimicrobial effect of citral, eugenol, and hexanal in combination with heat shock (HS) was evaluated in terms of the growth, biofilm formation, swarming, and expression of virulence genes of STEC serotypes (O157:H7, O103, O111, and O26). Eugenol was the most effective compound against the growth of E. coli strains (MBC = 0.58 to 0.73 mg/mL), followed by citral (MBC = 0.86 to 1.26 mg/mL) and hexanal (MBC = 2.24 to 2.52 mg/mL). Biofilm formation and swarming motility have great variability between STEC strains. Natural compounds-alone or combined with HS-inhibited biofilm formation; however, swarming motility was induced by most treatments. The expression of the studied genes during biofilm formation and swarming under natural antimicrobials was affected but not in a uniform pattern. These treatments could be used to control contamination of STEC and inhibit biofilm formation.
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Król-Górniak A, Pomastowski P, Railean-Plugaru V, Žuvela P, Wong MW, Pauter K, Szultka-Młyńska M, Buszewski B. The study of the molecular mechanism of Lactobacillus paracasei clumping via divalent metal ions by electrophoretic separation. J Chromatogr A 2021; 1652:462127. [PMID: 34214833 DOI: 10.1016/j.chroma.2021.462127] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 03/17/2021] [Accepted: 03/26/2021] [Indexed: 11/18/2022]
Abstract
In this work, the molecular mechanism of Lactobacillus paracasei bio-colloid clumping under divalent metal ions treatment such as zinc, copper and magnesium at constant concentrations was studied. The work involved experimental (electrophoretic - capillary electrophoresis in pseudo-isotachophoresis mode, spectroscopic and spectrometric - FT-IR and MALDI-TOF-MS, microscopic - fluorescent microscopy, and flow cytometry) and theoretical (DFT calculations of model complex systems) characterization. Electrophoretic results have pointed out the formation of aggregates under the Zn2+ and Cu2+ modification, whereas the use of the Mg2+ allowed focusing the zone of L. paracasei biocolloid. According to the FT-IR analysis, the major functional groups involved in the aggregation are deprotonated carboxyl and amide groups derived from the bacterial surface structure. Nature of the divalent metal ions was shown to be one of the key factors influencing the bacterial aggregation process. Proteomic analysis showed that surface modification had a considerable impact on bacteria molecular profiles and protein expression, mainly linked to the activation of carbohydrate and nucleotides metabolism as well with the transcription regulation and membrane transport. Density-functional theory (DFT) calculations of modeled Cu2+, Mg2+ and Zn2+ coordination complexes support the interaction between the divalent metal ions and bacterial proteins. Consequently, the possible mechanism of the aggregation phenomenon was proposed. Therefore, this comprehensive study could be further applied in evaluation of biocolloid aggregation under different types of metal ions.
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Affiliation(s)
- Anna Król-Górniak
- Chair of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Poland; Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, 7 Gagarina Str., 87-100 Torun, Poland
| | - Paweł Pomastowski
- Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, 7 Gagarina Str., 87-100 Torun, Poland
| | - Viorica Railean-Plugaru
- Chair of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Poland; Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, 7 Gagarina Str., 87-100 Torun, Poland
| | - Petar Žuvela
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore
| | - Ming Wah Wong
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore
| | - Katarzyna Pauter
- Chair of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Poland; Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, 7 Gagarina Str., 87-100 Torun, Poland
| | - Małgorzata Szultka-Młyńska
- Chair of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Poland; Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, 7 Gagarina Str., 87-100 Torun, Poland
| | - Bogusław Buszewski
- Chair of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Poland; Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, 7 Gagarina Str., 87-100 Torun, Poland.
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31
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Ageorges V, Monteiro R, Leroy S, Burgess CM, Pizza M, Chaucheyras-Durand F, Desvaux M. Molecular determinants of surface colonisation in diarrhoeagenic Escherichia coli (DEC): from bacterial adhesion to biofilm formation. FEMS Microbiol Rev 2021; 44:314-350. [PMID: 32239203 DOI: 10.1093/femsre/fuaa008] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 03/31/2020] [Indexed: 12/11/2022] Open
Abstract
Escherichia coli is primarily known as a commensal colonising the gastrointestinal tract of infants very early in life but some strains being responsible for diarrhoea, which can be especially severe in young children. Intestinal pathogenic E. coli include six pathotypes of diarrhoeagenic E. coli (DEC), namely, the (i) enterotoxigenic E. coli, (ii) enteroaggregative E. coli, (iii) enteropathogenic E. coli, (iv) enterohemorragic E. coli, (v) enteroinvasive E. coli and (vi) diffusely adherent E. coli. Prior to human infection, DEC can be found in natural environments, animal reservoirs, food processing environments and contaminated food matrices. From an ecophysiological point of view, DEC thus deal with very different biotopes and biocoenoses all along the food chain. In this context, this review focuses on the wide range of surface molecular determinants acting as surface colonisation factors (SCFs) in DEC. In the first instance, SCFs can be broadly discriminated into (i) extracellular polysaccharides, (ii) extracellular DNA and (iii) surface proteins. Surface proteins constitute the most diverse group of SCFs broadly discriminated into (i) monomeric SCFs, such as autotransporter (AT) adhesins, inverted ATs, heat-resistant agglutinins or some moonlighting proteins, (ii) oligomeric SCFs, namely, the trimeric ATs and (iii) supramolecular SCFs, including flagella and numerous pili, e.g. the injectisome, type 4 pili, curli chaperone-usher pili or conjugative pili. This review also details the gene regulatory network of these numerous SCFs at the various stages as it occurs from pre-transcriptional to post-translocational levels, which remains to be fully elucidated in many cases.
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Affiliation(s)
- Valentin Ageorges
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France
| | - Ricardo Monteiro
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France.,GSK, Via Fiorentina 1, 53100 Siena, Italy
| | - Sabine Leroy
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France
| | - Catherine M Burgess
- Food Safety Department, Teagasc Food Research Centre, Ashtown, Dublin 15, Ireland
| | | | - Frédérique Chaucheyras-Durand
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France.,Lallemand Animal Nutrition SAS, F-31702 Blagnac Cedex, France
| | - Mickaël Desvaux
- Université Clermont Auvergne, INRAE, MEDiS, F-63000 Clermont-Ferrand, France
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Sánchez F, Fuenzalida V, Ramos R, Escobar B, Neira V, Borie C, Lapierre L, López P, Venegas L, Dettleff P, Johnson T, Fuentes-Castillo D, Lincopan N, Galarce N. Genomic features and antimicrobial resistance patterns of Shiga toxin-producing Escherichia coli strains isolated from food in Chile. Zoonoses Public Health 2021; 68:226-238. [PMID: 33619864 DOI: 10.1111/zph.12818] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 12/18/2020] [Accepted: 01/18/2021] [Indexed: 02/06/2023]
Abstract
Shiga toxin-producing Escherichia coli (STEC) is a zoonotic pathogen that causes severe illness in humans, often associated with foodborne outbreaks. Antimicrobial resistance among foodborne E. coli has increased over the last decades becoming a public health issue. In this study, the presence and features of STEC were investigated in samples of meat, seafood, vegetables and ready-to-eat street-vended food collected in Chile, using a genomic and microbiological approach. Phenotypic and genotypic antimicrobial resistance profiles were determined, and serotype, phylogroup, sequence type (ST) and phylogenomics were predicted using bioinformatic tools. Three thousand three hundred samples collected in 2019 were screened, of which 18 were positive for STEC strains (0.5%), with stx2a (61.1%) being the predominant stx subtype. The presence of the virulence genes lpfA (100%), iha and ehaA (94.4%), and ehxA, hlyA and saa (83.3%) was confirmed among the STEC strains; the Locus of adhesion and autoaggregation (LAA) was predicted in 14 (77.8%) strains. Strains displayed resistance to colistin (100%), and intermediate resistance to enrofloxacin (11.1%) and chloramphenicol (5.6%). In this regard, mutations in the two-component regulatory system genes pmrA (S29G), pmrB (D283G) and phoP (I44L), and the presence of the qnrB19 gene were confirmed. STEC strains belonged to ST11231 (38.9%), ST297 and ST58 (16.7% each), and ST1635, ST11232, ST446, ST442 and ST54 (5.6% each), and the most frequently detected serotypes were O113:H21 (44.4%), O130:H11 and O116:H21 (16.7% each), and O174:H21 (11.1%). Strains belonging to the international ST58 showed genomic relatedness with worldwide strains from human and non-human sources. Our study reports for the first time the genomic profile of STEC strains isolated from food in Chile, highlighting the presence of international clones and sequence types commonly associated with human infections in different geographical regions, as well as the convergence of virulence and resistance in STEC lineages circulating in this country.
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Affiliation(s)
- Fernando Sánchez
- Facultad de Ciencias Veterinarias y Pecuarias, Departamento de Medicina Preventiva Animal, Universidad de Chile, Santiago, Chile.,Programa de Magíster en Ciencias Animales y Veterinarias, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago, Chile
| | - Verónica Fuenzalida
- Facultad de Ciencias Veterinarias y Pecuarias, Departamento de Medicina Preventiva Animal, Universidad de Chile, Santiago, Chile
| | - Romina Ramos
- Facultad de Ciencias Veterinarias y Pecuarias, Departamento de Medicina Preventiva Animal, Universidad de Chile, Santiago, Chile
| | - Beatriz Escobar
- Facultad de Ciencias Veterinarias y Pecuarias, Departamento de Medicina Preventiva Animal, Universidad de Chile, Santiago, Chile
| | - Víctor Neira
- Facultad de Ciencias Veterinarias y Pecuarias, Departamento de Medicina Preventiva Animal, Universidad de Chile, Santiago, Chile
| | - Consuelo Borie
- Facultad de Ciencias Veterinarias y Pecuarias, Departamento de Medicina Preventiva Animal, Universidad de Chile, Santiago, Chile
| | - Lisette Lapierre
- Facultad de Ciencias Veterinarias y Pecuarias, Departamento de Medicina Preventiva Animal, Universidad de Chile, Santiago, Chile
| | - Paulina López
- Facultad de Ciencias Veterinarias y Pecuarias, Departamento de Medicina Preventiva Animal, Universidad de Chile, Santiago, Chile
| | - Lucas Venegas
- Facultad de Ciencias Veterinarias y Pecuarias, Departamento de Medicina Preventiva Animal, Universidad de Chile, Santiago, Chile
| | - Phillip Dettleff
- Laboratorio FAVET-INBIOGEN, Facultad de Ciencias Veterinarias y Pecuarias, Departamento de Fomento de la Producción Animal, Universidad de Chile, Santiago, Chile.,Escuela de Medicina Veterinaria, Facultad de Recursos Naturales y Medicina Veterinaria, Universidad Santo Tomás, Santiago, Chile
| | - Timothy Johnson
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, MI, USA
| | - Danny Fuentes-Castillo
- Faculdade de Medicina Veterinária e Zootecnia, Departamento de Patología, Universidade de São Paulo, São Paulo, Brazil
| | - Nilton Lincopan
- Departamento de Microbiología, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brazil
| | - Nicolás Galarce
- Facultad de Ciencias Veterinarias y Pecuarias, Departamento de Medicina Preventiva Animal, Universidad de Chile, Santiago, Chile
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33
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Cortimiglia C, Borney MF, Bassi D, Cocconcelli PS. Genomic Investigation of Virulence Potential in Shiga Toxin Escherichia coli (STEC) Strains From a Semi-Hard Raw Milk Cheese. Front Microbiol 2021; 11:629189. [PMID: 33597935 PMCID: PMC7882498 DOI: 10.3389/fmicb.2020.629189] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 12/30/2020] [Indexed: 12/22/2022] Open
Abstract
Shiga-toxin-producing Escherichia coli (STEC) represents a significant cause of foodborne disease. In the last years, an increasing number of STEC infections associated with the consumption of raw and pasteurized milk cheese have been reported, contributing to raise the public awareness. The aim of this study is to evaluate the main genomic features of STEC strains isolated from a semi-hard raw milk cheese, focusing on their pathogenic potential. The analysis of 75 cheese samples collected during the period between April 2019 and January 2020 led to the isolation of seven strains from four stx-positive enrichment. The genome investigation evidenced the persistence of two serotypes, O174:H2 and O116:H48. All strains carried at least one stx gene and were negative for eae gene. The virulence gene pattern was homogeneous among the serogroup/ST and included adherence factors (lpfA, iha, ompT, papC, saa, sab, hra, and hes), enterohemolysin (ehxA), serum resistance (iss, tra), cytotoxin-encoding genes like epeA and espP, and the Locus of Adhesion and Autoaggregation Pathogenicity Islands (LAA PAIs) typically found in Locus of Enterocyte Effacement (LEE)-negative STEC. Genome plasticity indicators, namely, prophagic sequences carrying stx genes and plasmid replicons, were detected, leading to the possibility to share virulence determinants with other strains. Overall, our work adds new knowledge on STEC monitoring in raw milk dairy products, underlining the fundamental role of whole genome sequencing (WGS) for typing these unknown isolates. Since, up to now, some details about STEC pathogenesis mechanism is lacking, the continuous monitoring in order to protect human health and increase knowledge about STEC genetic features becomes essential.
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Affiliation(s)
- Claudia Cortimiglia
- Dipartimento di Scienze e Tecnologie Alimentari per una Filiera Agro-Alimentare Sostenibile (DISTAS), Università Cattolica del Sacro Cuore, Piacenza, Italy
| | - Maria Francesca Borney
- Dipartimento di Scienze e Tecnologie Alimentari per una Filiera Agro-Alimentare Sostenibile (DISTAS), Università Cattolica del Sacro Cuore, Piacenza, Italy
| | - Daniela Bassi
- Dipartimento di Scienze e Tecnologie Alimentari per una Filiera Agro-Alimentare Sostenibile (DISTAS), Università Cattolica del Sacro Cuore, Piacenza, Italy
| | - Pier Sandro Cocconcelli
- Dipartimento di Scienze e Tecnologie Alimentari per una Filiera Agro-Alimentare Sostenibile (DISTAS), Università Cattolica del Sacro Cuore, Piacenza, Italy
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34
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Nehoya KN, Hamatui N, Shilangale RP, Onywera H, Kennedy J, Mwapagha LM. Characterization of Shiga toxin-producing Escherichia coli in raw beef from informal and commercial abattoirs. PLoS One 2020; 15:e0243828. [PMID: 33332397 PMCID: PMC7746290 DOI: 10.1371/journal.pone.0243828] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 11/26/2020] [Indexed: 11/19/2022] Open
Abstract
Shiga toxin-producing Escherichia coli are foodborne pathogens that are mostly associated with beef products and have been implicated in human illness. E.coli-associated illness range from asymptomatic conditions of mild diarrhoea to haemorrhagic colitis which can progress into life threatening haemolytic uremic syndrome (HUS). Beef from cattle are regarded as the main reservoir of Shiga toxin-producing E. coli (STEC) pathogen. The aim of this study was to assess the level and sources of contamination of raw beef with STEC, and determine the incidences of STEC strains in raw beef from informal and commercial abattoirs in Windhoek, Namibia. A total of 204 raw beef samples, 37 equipment and 29 hand swabs were collected and tested for STEC. The meat samples were first enriched with pre-warmed buffered peptone water, cultured on Tryptone Bile X-Glucuronide and CHROMagar STEC, and then sub-cultured on nutrient agar. The presence of E.coli in the samples was confirmed by using VITEK 2 E.coli identification cards and PCR. The overall prevalence of STEC in the meat samples from both the abattoirs was 41.66% raw beef samples; 5.40% equipment swabs; and none of the hand swabs was STEC positive. From the STEC positive meat samples 29.41% contained one of the major STEC strains. Moreover, 52% of the 25 samples that contained the major STECs were characterised by eae and stx1, 8% characterised by eae and stx2 while 40% were characterised by eae, stx1 and stx2 virulence genes. This study has revealed the necessity for proper training on meat safety (for meat handlers) as well as the development, implementation and maintenance of effective sanitary dressing procedures at abattoirs to eliminate beef contamination by STECs thereby ensuring the production of wholesome meat, and to prevent the occurrences of STEC infections.
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Affiliation(s)
- Kaarina N. Nehoya
- Department of Health Sciences, Faculty of Health and Applied Sciences, Namibia University of Science and Technology, Windhoek, Namibia
- Directorate of Veterinary Services, Ministry of Agriculture Water and Forestry, Windhoek, Namibia
| | - Ndinomholo Hamatui
- Department of Health Sciences, Faculty of Health and Applied Sciences, Namibia University of Science and Technology, Windhoek, Namibia
| | - Renatus P. Shilangale
- Central Veterinary Laboratory, Ministry of Agriculture Water and Forestry, Windhoek, Namibia
| | - Harris Onywera
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
- Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Jeya Kennedy
- Department of Natural and Applied Sciences, Faculty of Health and Applied Sciences, Namibia University of Science and Technology, Windhoek, Namibia
| | - Lamech M. Mwapagha
- Department of Natural and Applied Sciences, Faculty of Health and Applied Sciences, Namibia University of Science and Technology, Windhoek, Namibia
- * E-mail:
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35
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Biggel M, Xavier BB, Johnson JR, Nielsen KL, Frimodt-Møller N, Matheeussen V, Goossens H, Moons P, Van Puyvelde S. Horizontally acquired papGII-containing pathogenicity islands underlie the emergence of invasive uropathogenic Escherichia coli lineages. Nat Commun 2020; 11:5968. [PMID: 33235212 PMCID: PMC7686366 DOI: 10.1038/s41467-020-19714-9] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 10/27/2020] [Indexed: 12/29/2022] Open
Abstract
Escherichia coli is the leading cause of urinary tract infection, one of the most common bacterial infections in humans. Despite this, a genomic perspective is lacking regarding the phylogenetic distribution of isolates associated with different clinical syndromes. Here, we present a large-scale phylogenomic analysis of a spatiotemporally and clinically diverse set of 907 E. coli isolates, including 722 uropathogenic E. coli (UPEC) isolates. A genome-wide association approach identifies the (P-fimbriae-encoding) papGII locus as the key feature distinguishing invasive UPEC, defined as isolates associated with severe UTI, i.e., kidney infection (pyelonephritis) or urinary-source bacteremia, from non-invasive UPEC, defined as isolates associated with asymptomatic bacteriuria or bladder infection (cystitis). Within the E. coli population, distinct invasive UPEC lineages emerged through repeated horizontal acquisition of diverse papGII-containing pathogenicity islands. Our findings elucidate the molecular determinants of severe UTI and have implications for the early detection of this pathogen.
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Affiliation(s)
- Michael Biggel
- Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium.
| | - Basil B Xavier
- Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium
| | - James R Johnson
- Veterans Affairs Medical Center and University of Minnesota, Minneapolis, MN, USA
| | - Karen L Nielsen
- Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark
| | | | - Veerle Matheeussen
- Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium
- Laboratory of Clinical Microbiology, Antwerp University Hospital, Antwerp, Belgium
| | - Herman Goossens
- Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium
- Laboratory of Clinical Microbiology, Antwerp University Hospital, Antwerp, Belgium
| | - Pieter Moons
- Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium
| | - Sandra Van Puyvelde
- Laboratory of Medical Microbiology, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium.
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), Department of Medicine, University of Cambridge, Cambridge, CB2 0SP, UK.
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36
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Desvaux M, Dalmasso G, Beyrouthy R, Barnich N, Delmas J, Bonnet R. Pathogenicity Factors of Genomic Islands in Intestinal and Extraintestinal Escherichia coli. Front Microbiol 2020; 11:2065. [PMID: 33101219 PMCID: PMC7545054 DOI: 10.3389/fmicb.2020.02065] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 08/05/2020] [Indexed: 12/20/2022] Open
Abstract
Escherichia coli is a versatile bacterial species that includes both harmless commensal strains and pathogenic strains found in the gastrointestinal tract in humans and warm-blooded animals. The growing amount of DNA sequence information generated in the era of "genomics" has helped to increase our understanding of the factors and mechanisms involved in the diversification of this bacterial species. The pathogenic side of E. coli that is afforded through horizontal transfers of genes encoding virulence factors enables this bacterium to become a highly diverse and adapted pathogen that is responsible for intestinal or extraintestinal diseases in humans and animals. Many of the accessory genes acquired by horizontal transfers form syntenic blocks and are recognized as genomic islands (GIs). These genomic regions contribute to the rapid evolution, diversification and adaptation of E. coli variants because they are frequently subject to rearrangements, excision and transfer, as well as to further acquisition of additional DNA. Here, we review a subgroup of GIs from E. coli termed pathogenicity islands (PAIs), a concept defined in the late 1980s by Jörg Hacker and colleagues in Werner Goebel's group at the University of Würzburg, Würzburg, Germany. As with other GIs, the PAIs comprise large genomic regions that differ from the rest of the genome by their G + C content, by their typical insertion within transfer RNA genes, and by their harboring of direct repeats (at their ends), integrase determinants, or other mobility loci. The hallmark of PAIs is their contribution to the emergence of virulent bacteria and to the development of intestinal and extraintestinal diseases. This review summarizes the current knowledge on the structure and functional features of PAIs, on PAI-encoded E. coli pathogenicity factors and on the role of PAIs in host-pathogen interactions.
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Affiliation(s)
- Mickaël Desvaux
- Université Clermont Auvergne, INRAE, MEDiS, Clermont-Ferrand, France
| | - Guillaume Dalmasso
- UMR Inserm 1071, USC-INRAE 2018, M2iSH, Université Clermont Auvergne, Clermont-Ferrand, France
| | - Racha Beyrouthy
- UMR Inserm 1071, USC-INRAE 2018, M2iSH, Université Clermont Auvergne, Clermont-Ferrand, France
- Laboratoire de Bactériologie, CHU Clermont-Ferrand, Clermont-Ferrand, France
| | - Nicolas Barnich
- UMR Inserm 1071, USC-INRAE 2018, M2iSH, Université Clermont Auvergne, Clermont-Ferrand, France
| | - Julien Delmas
- UMR Inserm 1071, USC-INRAE 2018, M2iSH, Université Clermont Auvergne, Clermont-Ferrand, France
- Laboratoire de Bactériologie, CHU Clermont-Ferrand, Clermont-Ferrand, France
| | - Richard Bonnet
- UMR Inserm 1071, USC-INRAE 2018, M2iSH, Université Clermont Auvergne, Clermont-Ferrand, France
- Laboratoire de Bactériologie, CHU Clermont-Ferrand, Clermont-Ferrand, France
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Carter MQ, Pham A, He X, Hnasko R. Genomic Insight into Natural Inactivation of Shiga Toxin 2 Production in an EnvironmentalEscherichia coliStrain Producing Shiga Toxin 1. Foodborne Pathog Dis 2020; 17:555-567. [DOI: 10.1089/fpd.2019.2767] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Affiliation(s)
- Michelle Qiu Carter
- Produce Safety and Microbiology Research Unit, Western Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, Albany, California
| | - Antares Pham
- Produce Safety and Microbiology Research Unit, Western Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, Albany, California
| | - Xiaohua He
- Foodborne Toxin Prevention and Detection Unit, Western Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, Albany, California
| | - Robert Hnasko
- Produce Safety and Microbiology Research Unit, Western Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, Albany, California
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Jinnerot T, Tomaselli ATP, Johannessen GS, Söderlund R, Urdahl AM, Aspán A, Sekse C. The prevalence and genomic context of Shiga toxin 2a genes in E. coli found in cattle. PLoS One 2020; 15:e0232305. [PMID: 32785271 PMCID: PMC7423110 DOI: 10.1371/journal.pone.0232305] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 07/20/2020] [Indexed: 11/25/2022] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) that cause severe disease predominantly carry the toxin gene variant stx2a. However, the role of Shiga toxin in the ruminant reservoirs of this zoonotic pathogen is poorly understood and strains that cause severe disease in humans (HUSEC) likely constitute a small and atypical subset of the overall STEC flora. The aim of this study was to investigate the presence of stx2a in samples from cattle and to isolate and characterize stx2a-positive E. coli. In nationwide surveys in Sweden and Norway samples were collected from individual cattle or from cattle herds, respectively. Samples were tested for Shiga toxin genes by real-time PCR and amplicon sequencing and stx2a-positive isolates were whole genome sequenced. Among faecal samples from Sweden, stx1 was detected in 37%, stx2 in 53% and stx2a in 5% and in skin (ear) samples in 64%, 79% and 2% respectively. In Norway, 79% of the herds were positive for stx1, 93% for stx2 and 17% for stx2a. Based on amplicon sequencing the most common stx2 types in samples from Swedish cattle were stx2a and stx2d. Multilocus sequence typing (MLST) of 39 stx2a-positive isolates collected from both countries revealed substantial diversity with 19 different sequence types. Only a few classical LEE-positive strains similar to HUSEC were found among the stx2a-positive isolates, notably a single O121:H19 and an O26:H11. Lineages known to include LEE-negative HUSEC were also recovered including, such as O113:H21 (sequence type ST-223), O130:H11 (ST-297), and O101:H33 (ST-330). We conclude that E. coli encoding stx2a in cattle are ranging from strains similar to HUSEC to unknown STEC variants. Comparison of isolates from human HUS cases to related STEC from the ruminant reservoirs can help identify combinations of virulence attributes necessary to cause HUS, as well as provide a better understanding of the routes of infection for rare and emerging pathogenic STEC.
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Affiliation(s)
| | | | | | | | | | - Anna Aspán
- National Veterinary Institute, Uppsala, Sweden
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Deciphering Additional Roles for the EF-Tu, l-Asparaginase II and OmpT Proteins of Shiga Toxin-Producing Escherichia coli. Microorganisms 2020; 8:microorganisms8081184. [PMID: 32759661 PMCID: PMC7464798 DOI: 10.3390/microorganisms8081184] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 07/31/2020] [Accepted: 08/01/2020] [Indexed: 12/14/2022] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) causes outbreaks and sporadic cases of gastroenteritis. STEC O157:H7 is the most clinically relevant serotype in the world. The major virulence determinants of STEC O157:H7 are the Shiga toxins and the locus of enterocyte effacement. However, several accessory virulence factors, mainly outer membrane proteins (OMPs) that interact with the host cells may contribute to the virulence of this pathogen. Previously, the elongation factor thermo unstable (EF-Tu), l-asparaginase II and OmpT proteins were identified as antigens in OMP extracts of STEC. The known subcellular location of EF-Tu and l-asparaginase II are the cytoplasm and periplasm, respectively. Therefore, we investigate whether these two proteins may localize on the surface of STEC and, if so, what roles they have at this site. On the other hand, the OmpT protein, a well characterized protease, has been described as participating in the adhesion of extraintestinal pathogenic E. coli strains. Thus, we investigate whether OmpT has this role in STEC. Our results show that the EF-Tu and l-asparaginase II are secreted by O157:H7 and may also localize on the surface of this bacterium. EF-Tu was identified in outer membrane vesicles (OMVs), suggesting it as a possible export mechanism for this protein. Notably, we found that l-asparaginase II secreted by O157:H7 inhibits T-lymphocyte proliferation, but the role of EF-Tu at the surface of this bacterium remains to be elucidated. In the case of OmpT, we show its participation in the adhesion of O157:H7 to human epithelial cells. Thus, this study extends the knowledge of the pathogenic mechanisms of STEC.
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40
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Vélez MV, Colello R, Etcheverría AI, Vidal RM, Montero DA, Acuña P, Guillén Fretes RM, Toro M, Padola NL. Distribution of Locus of Adhesion and Autoaggregation and hes Gene in STEC Strains from Countries of Latin America. Curr Microbiol 2020; 77:2111-2117. [DOI: 10.1007/s00284-020-02062-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 05/27/2020] [Indexed: 02/07/2023]
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41
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Montero DA, Del Canto F, Salazar JC, Céspedes S, Cádiz L, Arenas-Salinas M, Reyes J, Oñate Á, Vidal RM. Immunization of mice with chimeric antigens displaying selected epitopes confers protection against intestinal colonization and renal damage caused by Shiga toxin-producing Escherichia coli. NPJ Vaccines 2020; 5:20. [PMID: 32194997 PMCID: PMC7067774 DOI: 10.1038/s41541-020-0168-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 02/14/2020] [Indexed: 12/14/2022] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) cause diarrhea and dysentery, which may progress to hemolytic uremic syndrome (HUS). Vaccination has been proposed as a preventive approach against STEC infection; however, there is no vaccine for humans and those used in animals reduce but do not eliminate the intestinal colonization of STEC. The OmpT, Cah and Hes proteins are widely distributed among clinical STEC strains and are recognized by serum IgG and IgA in patients with HUS. Here, we develop a vaccine formulation based on two chimeric antigens containing epitopes of OmpT, Cah and Hes proteins against STEC strains. Intramuscular and intranasal immunization of mice with these chimeric antigens elicited systemic and local long-lasting humoral responses. However, the class of antibodies generated was dependent on the adjuvant and the route of administration. Moreover, while intramuscular immunization with the combination of the chimeric antigens conferred protection against colonization by STEC O157:H7, the intranasal conferred protection against renal damage caused by STEC O91:H21. This preclinical study supports the potential use of this formulation based on recombinant chimeric proteins as a preventive strategy against STEC infections.
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Affiliation(s)
- David A Montero
- 1Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,2Programa Disciplinario de Inmunología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Felipe Del Canto
- 1Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Juan C Salazar
- 1Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Sandra Céspedes
- 1Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Leandro Cádiz
- 1Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Mauricio Arenas-Salinas
- 3Centro de Bioinformática y Simulación Molecular, Facultad de Ingeniería, Universidad de Talca, Talca, Chile
| | - José Reyes
- 4Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Ángel Oñate
- 4Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Roberto M Vidal
- 1Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,5Instituto Milenio de Inmunología e Inmunoterapia, Facultad de Medicina, Universidad de Chile, Santiago, Chile
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42
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Maria Ferreira Cavalcanti A, Tavanelli Hernandes R, Harummyy Takagi E, Ernestina Cabílio Guth B, de Lima Ori É, Regina Schicariol Pinheiro S, Sueli de Andrade T, Louzada Oliveira S, Cecilia Cergole-Novella M, Rodrigues Francisco G, dos Santos LF. Virulence Profiling and Molecular Typing of Shiga Toxin-Producing E. coli (STEC) from Human Sources in Brazil. Microorganisms 2020; 8:microorganisms8020171. [PMID: 31991731 PMCID: PMC7074907 DOI: 10.3390/microorganisms8020171] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 01/21/2020] [Accepted: 01/22/2020] [Indexed: 12/12/2022] Open
Abstract
Since no recent data characterizing Shiga toxin-producing E. coli (STEC) from human infections in Brazil are available, the present study aimed to investigate serotypes, stx genotypes, and accessory virulence genes, and also to perform pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST) of 43 STEC strains recovered from 2007 to 2017. Twenty-one distinct serotypes were found, with serotype O111:H8 being the most common. However, serotypes less frequently reported in human diseases were also found and included a hybrid STEC/ETEC O100:H25 clone. The majority of the strains carried stx1a as the sole stx genotype and were positive for the eae gene. Regarding the occurrence of 28 additional virulence genes associated with plasmids and pathogenicity islands, a diversity of profiles was found especially among the eae-harboring strains, which had combinations of markers composed of up to 12 distinct genes. Although PFGE analysis demonstrated genetic diversity between serotypes such as O157:H7, O111:H8, O26:H11, O118:H16, and O123:H2, high genetic relatedness was found for strains of serotypes O24:H4 and O145:H34. MLST allowed the identification of 17 distinct sequence types (STs) with ST 16 and 21 being the most common ones. Thirty-five percent of the strains studied were not typeable by the currently used MLST approach, suggesting new STs. Although STEC O111:H8 remains the leading serotype in Brazil, a diversity of other serotypes, some carrying virulence genes and belonging to STs incriminated as causing severe disease, were found in this study. Further studies are needed to determine whether they have any epidemiological relevance.
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Affiliation(s)
- Adriene Maria Ferreira Cavalcanti
- Centro de Bacteriologia (National Reference Laboratory for STEC infections and HUS), Instituto Adolfo Lutz, São Paulo 01246-000, SP, Brasil; (A.M.F.C.); (E.H.T.); (S.R.S.P.); (T.S.d.A.); (M.C.C.-N.); (G.R.F.)
| | - Rodrigo Tavanelli Hernandes
- Departamento de Microbiologia e Imunologia, Instituto de Biociências, Universidade Estadual Paulista, Botucatu 18618-970, SP, Brasil; (R.T.H.); (S.L.O.)
| | - Elizabeth Harummyy Takagi
- Centro de Bacteriologia (National Reference Laboratory for STEC infections and HUS), Instituto Adolfo Lutz, São Paulo 01246-000, SP, Brasil; (A.M.F.C.); (E.H.T.); (S.R.S.P.); (T.S.d.A.); (M.C.C.-N.); (G.R.F.)
| | - Beatriz Ernestina Cabílio Guth
- Departamento de Microbiologia, Imunologia, Parasitologia, Escola Paulista de Medicina Universidade Federal de São Paulo, São Paulo 04023-062, SP, Brasil;
| | - Érica de Lima Ori
- Centro de Bacteriologia (National Reference Laboratory for STEC infections and HUS), Instituto Adolfo Lutz, São Paulo 01246-000, SP, Brasil; (A.M.F.C.); (E.H.T.); (S.R.S.P.); (T.S.d.A.); (M.C.C.-N.); (G.R.F.)
| | - Sandra Regina Schicariol Pinheiro
- Centro de Bacteriologia (National Reference Laboratory for STEC infections and HUS), Instituto Adolfo Lutz, São Paulo 01246-000, SP, Brasil; (A.M.F.C.); (E.H.T.); (S.R.S.P.); (T.S.d.A.); (M.C.C.-N.); (G.R.F.)
| | - Tânia Sueli de Andrade
- Centro de Bacteriologia (National Reference Laboratory for STEC infections and HUS), Instituto Adolfo Lutz, São Paulo 01246-000, SP, Brasil; (A.M.F.C.); (E.H.T.); (S.R.S.P.); (T.S.d.A.); (M.C.C.-N.); (G.R.F.)
| | - Samara Louzada Oliveira
- Departamento de Microbiologia e Imunologia, Instituto de Biociências, Universidade Estadual Paulista, Botucatu 18618-970, SP, Brasil; (R.T.H.); (S.L.O.)
| | - Maria Cecilia Cergole-Novella
- Centro de Bacteriologia (National Reference Laboratory for STEC infections and HUS), Instituto Adolfo Lutz, São Paulo 01246-000, SP, Brasil; (A.M.F.C.); (E.H.T.); (S.R.S.P.); (T.S.d.A.); (M.C.C.-N.); (G.R.F.)
| | - Gabriela Rodrigues Francisco
- Centro de Bacteriologia (National Reference Laboratory for STEC infections and HUS), Instituto Adolfo Lutz, São Paulo 01246-000, SP, Brasil; (A.M.F.C.); (E.H.T.); (S.R.S.P.); (T.S.d.A.); (M.C.C.-N.); (G.R.F.)
| | - Luís Fernando dos Santos
- Centro de Bacteriologia (National Reference Laboratory for STEC infections and HUS), Instituto Adolfo Lutz, São Paulo 01246-000, SP, Brasil; (A.M.F.C.); (E.H.T.); (S.R.S.P.); (T.S.d.A.); (M.C.C.-N.); (G.R.F.)
- Correspondence: ; Tel.: +55-11-3068-2896
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Koutsoumanis K, Allende A, Alvarez‐Ordóñez A, Bover‐Cid S, Chemaly M, Davies R, De Cesare A, Herman L, Hilbert F, Lindqvist R, Nauta M, Peixe L, Ru G, Simmons M, Skandamis P, Suffredini E, Jenkins C, Monteiro Pires S, Morabito S, Niskanen T, Scheutz F, da Silva Felício MT, Messens W, Bolton D. Pathogenicity assessment of Shiga toxin‐producing Escherichia coli (STEC) and the public health risk posed by contamination of food with STEC. EFSA J 2020. [DOI: 10.2903/j.efsa.2020.5967] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
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44
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Identification and detection of iha subtypes in LEE-negative Shiga toxin-producing Escherichia coli (STEC) strains isolated from humans, cattle and food. Heliyon 2019; 5:e03015. [PMID: 31879713 PMCID: PMC6920203 DOI: 10.1016/j.heliyon.2019.e03015] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 11/18/2019] [Accepted: 12/06/2019] [Indexed: 01/30/2023] Open
Abstract
LEE-negative Shiga toxin-producing Escherichia coli (STEC) strains are important cause of infection in humans and they should be included in the public health surveillance systems. Some isolates have been associated with haemolytic uremic syndrome (HUS) but the mechanisms of pathogenicity are is a field continuos broadening of knowledge. The IrgA homologue adhesin (Iha), encoded by iha, is an adherence-conferring protein and also a siderophore receptor distributed among LEE-negative STEC strains. This study reports the presence of different subtypes of iha in LEE-negative STEC strains. We used genomic analyses to design PCR assays for detecting each of the different iha subtypes and also, all the subtypes simultaneously. LEE-negative STEC strains were designed and different localizations of this gene in STEC subgroups were examinated. Genomic analysis detected iha in a high percentage of LEE-negative STEC strains. These strains generally carried iha sequences similar to those harbored by the Locus of Adhesion and Autoaggregation (LAA) or by the plasmid pO113. Besides, almost half of the strains carried both subtypes. Similar results were observed by PCR, detecting iha LAA in 87% of the strains (117/135) and iha pO113 in 32% of strains (43/135). Thus, we designed PCR assays that allow rapid detection of iha subtypes harbored by LEE-negative strains. These results highlight the need to investigate the individual and orchestrated role of virulence genes that determine the STEC capacity of causing serious disease, which would allow for identification of target candidates to develop therapies against HUS.
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G M Gonzalez A, M F Cerqueira A. Shiga toxin-producing Escherichia coli in the animal reservoir and food in Brazil. J Appl Microbiol 2019; 128:1568-1582. [PMID: 31650661 DOI: 10.1111/jam.14500] [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] [Received: 05/20/2019] [Revised: 09/18/2019] [Accepted: 10/22/2019] [Indexed: 12/11/2022]
Abstract
Shiga toxin-producing Escherichia coli (STEC) is a zoonotic pathotype associated with human gastrointestinal disease that may progress to severe complications. Ruminants, especially cattle, are the main reservoirs of STEC contaminating the environment and foods of animal or vegetable origin. Besides Shiga toxin, other virulence factors are involved in STEC virulence. O157:H7 remains the most frequent serotype associated with disease. In Brazil, the prevalence of STEC reaches values as high as 90% in cattle and 20% in meat products which may impact the Brazilian food export trade. However, only few reports are related to human disease. The stx1 gene prevails in cattle, whereas the stx2 gene is more frequent in food. Several STEC serotypes have been isolated from cattle and food in Brazil, including the O157:H7, O111:NT, NT:H19 as well as O26 and O103 serogroups. O113: H21 STEC strains are frequent in ruminants and foods but with no report in human disease. The virulence profile of Brazilian STEC strains from cattle and food suggests a pathogenic potential to humans, although some differences with clinical strains have been detected. Further studies, employing recent and more discriminative techniques are in need to better clarify their virulence potential.
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Affiliation(s)
- Alice G M Gonzalez
- Departamento de Bromatologia, Universidade Federal Fluminense, Niterói, Brazil
| | - Aloysio M F Cerqueira
- Departamento de Microbiologia e Parasitologia, Universidade Federal Fluminense, Niterói, Brazil
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Montero DA, Canto FD, Velasco J, Colello R, Padola NL, Salazar JC, Martin CS, Oñate A, Blanco J, Rasko DA, Contreras C, Puente JL, Scheutz F, Franz E, Vidal RM. Cumulative acquisition of pathogenicity islands has shaped virulence potential and contributed to the emergence of LEE-negative Shiga toxin-producing Escherichia coli strains. Emerg Microbes Infect 2019; 8:486-502. [PMID: 30924410 PMCID: PMC6455142 DOI: 10.1080/22221751.2019.1595985] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Shiga toxin-producing Escherichia coli (STEC) are foodborne pathogens causing severe gastroenteritis, which may lead to hemolytic uremic syndrome. The Locus of Enterocyte Effacement (LEE), a Pathogenicity Island (PAI), is a major determinant of intestinal epithelium attachment of a group of STEC strains; however, the virulence repertoire of STEC strains lacking LEE, has not been fully characterized. The incidence of LEE-negative STEC strains has increased in several countries, highlighting the relevance of their study. In order to gain insights into the basis for the emergence of LEE-negative STEC strains, we performed a large-scale genomic analysis of 367 strains isolated worldwide from humans, animals, food and the environment. We identified uncharacterized genomic islands, including two PAIs and one Integrative Conjugative Element. Additionally, the Locus of Adhesion and Autoaggregation (LAA) was the most prevalent PAI among LEE-negative strains and we found that it contributes to colonization of the mice intestine. Our comprehensive and rigorous comparative genomic and phylogenetic analyses suggest that the accumulative acquisition of PAIs has played an important, but currently unappreciated role, in the evolution of virulence in these strains. This study provides new knowledge on the pathogenicity of LEE-negative STEC strains and identifies molecular markers for their epidemiological surveillance.
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Affiliation(s)
- David Arturo Montero
- a Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile , Santiago , Chile
| | - Felipe Del Canto
- a Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile , Santiago , Chile
| | - Juliana Velasco
- b Servicio de Urgencia Infantil, Hospital Clínico de la Universidad de Chile "Dr. José Joaquín Aguirre" , Santiago , Chile
| | - Rocío Colello
- c Centro de Investigación Veterinaria Tandil, CONICET-CIC, Facultad de Ciencias Veterinarias, UNCPBA , Tandil , Argentina
| | - Nora Lia Padola
- c Centro de Investigación Veterinaria Tandil, CONICET-CIC, Facultad de Ciencias Veterinarias, UNCPBA , Tandil , Argentina
| | - Juan Carlos Salazar
- a Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile , Santiago , Chile
| | - Carla San Martin
- d Departamento de Microbiología, Facultad de Ciencias Biológicas , Universidad de Concepción , Concepción , Chile
| | - Angel Oñate
- d Departamento de Microbiología, Facultad de Ciencias Biológicas , Universidad de Concepción , Concepción , Chile
| | - Jorge Blanco
- e Laboratorio de Referencia de E. coli, Facultad de Veterinaria , Universidad de Santiago de Compostela , Lugo , España
| | - David A Rasko
- f Department of Microbiology and Immunology , University of Maryland School of Medicine , Baltimore , MD , USA
| | - Carmen Contreras
- g Departamento de Microbiología Molecular , Instituto de Biotecnología, Universidad Nacional Autónoma de México , Cuernavaca , México
| | - Jose Luis Puente
- g Departamento de Microbiología Molecular , Instituto de Biotecnología, Universidad Nacional Autónoma de México , Cuernavaca , México
| | - Flemming Scheutz
- h Department of Bacteria, Parasites and Fungi , The International Collaborating Centre for Reference and Research on Escherichia and Klebsiella, Statens Serum Institut , Copenhagen , Denmark
| | - Eelco Franz
- i National Institute for Public Health, Centre for Infectious Disease Control , Bilthoven , The Netherlands
| | - Roberto M Vidal
- a Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile , Santiago , Chile.,j Instituto Milenio de Inmunología e Inmunoterapia, Facultad de Medicina, Universidad de Chile , Santiago , Chile
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Hazard Identification and Characterization: Criteria for Categorizing Shiga Toxin-Producing Escherichia coli on a Risk Basis †. J Food Prot 2019; 82:7-21. [PMID: 30586326 DOI: 10.4315/0362-028x.jfp-18-291] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Shiga toxin-producing Escherichia coli (STEC) comprise a large, highly diverse group of strains. Since the emergence of STEC serotype O157:H7 as an important foodborne pathogen, serotype data have been used for identifying STEC strains, and this use continued as other serotypes were implicated in human infections. An estimated 470 STEC serotypes have been identified, which can produce one or more of the 12 known Shiga toxin (Stx) subtypes. The number of STEC serotypes that cause human illness varies but is probably higher than 100. However, many STEC virulence genes are mobile and can be lost or transferred to other bacteria; therefore, STEC strains that have the same serotype may not carry the same virulence genes or pose the same risk. Although serotype information is useful in outbreak investigations and surveillance studies, it is not a reliable means of assessing the human health risk posed by a particular STEC serotype. To contribute to the development of a set of criteria that would more reliably support hazard identification, this review considered each of the factors contributing to a negative human health outcome: mild diarrhea, bloody diarrhea, and hemolytic uremic syndrome (HUS). STEC pathogenesis involves entry into the human gut (often via ingestion), attachment to the intestinal epithelial cells, and elaboration of Stx. Production of Stx, which disrupts normal cellular functions and causes cell damage, alone without adherence of bacterial cells to gut epithelial cells is insufficient to cause severe illness. The principal adherence factor in STEC is the intimin protein coded by the eae gene. The aggregative adherence fimbriae adhesins regulated by the aggR gene of enteroaggregative E. coli strains are also effective adherence factors. The stx2a gene is most often present in locus of enterocyte effacement ( eae)-positive STEC strains and has consistently been associated with HUS. The stx2a gene has also been found in eae-negative, aggR-positive STEC that have caused HUS. HUS cases where other stx gene subtypes were identified indicate that other factors such as host susceptibility and the genetic cocktail of virulence genes in individual isolates may affect their association with severe diseases.
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Affiliation(s)
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- The Joint FAO/WHO Expert Meetings on Microbiological Risk Assessment (JEMRA) Secretariat, * Food Safety and Quality Unit, Agriculture and Consumer Protection Department, Food and Agriculture Organization of the United Nations, Viale delle Terme di Caracalla, 00153 Rome, Italy
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Lang C, Fruth A, Holland G, Laue M, Mühlen S, Dersch P, Flieger A. Novel type of pilus associated with a Shiga-toxigenic E. coli hybrid pathovar conveys aggregative adherence and bacterial virulence. Emerg Microbes Infect 2018; 7:203. [PMID: 30514915 PMCID: PMC6279748 DOI: 10.1038/s41426-018-0209-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 11/09/2018] [Accepted: 11/11/2018] [Indexed: 01/31/2023]
Abstract
A large German outbreak in 2011 was caused by a locus of enterocyte effacement (LEE)-negative enterohemorrhagic E. coli (EHEC) strain of the serotype O104:H4. This strain harbors markers that are characteristic of both EHEC and enteroaggregative E. coli (EAEC), including aggregative adhesion fimbriae (AAF) genes. Such rare EHEC/EAEC hybrids are highly pathogenic due to their possession of a combination of genes promoting severe toxicity and aggregative adhesion. We previously identified novel EHEC/EAEC hybrids and observed that one strain exhibited aggregative adherence but had no AAF genes. In this study, a genome sequence analysis showed that this strain belongs to the genoserotype O23:H8, MLST ST26, and harbors a 5.2 Mb chromosome and three plasmids. One plasmid carries some EAEC marker genes, such as aatA and genes with limited protein homology (11–61%) to those encoding the bundle-forming pilus (BFP) of enteropathogenic E. coli. Due to significant protein homology distance to known pili, we designated these as aggregate-forming pili (AFP)-encoding genes and the respective plasmid as pAFP. The afp operon was arranged similarly to the operon of BFP genes but contained an additional gene, afpA2, which is homologous to afpA. The deletion of the afp operon, afpA, or a nearby gene (afpR) encoding an AraC-like regulator, but not afpA2, led to a loss of pilin production, piliation, bacterial autoaggregation, and importantly, a >80% reduction in adhesion and cytotoxicity toward epithelial cells. Gene sets similar to the afp operon were identified in a variety of aatA-positive but AAF-negative intestinal pathogenic E. coli. In summary, we characterized widely distributed and novel fimbriae that are essential for aggregative adherence and cytotoxicity in a LEE-negative Shiga-toxigenic hybrid.
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Affiliation(s)
- Christina Lang
- Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institut, Wernigerode, Saxony-Anhalt, 38855, Germany
| | - Angelika Fruth
- Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institut, Wernigerode, Saxony-Anhalt, 38855, Germany
| | - Gudrun Holland
- Division of Advanced Light and Electron Microscopy, Robert Koch Institut, Berlin, 13353, Germany
| | - Michael Laue
- Division of Advanced Light and Electron Microscopy, Robert Koch Institut, Berlin, 13353, Germany
| | - Sabrina Mühlen
- Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, Braunschweig, Lower Saxony, 38124, Germany
| | - Petra Dersch
- Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, Braunschweig, Lower Saxony, 38124, Germany
| | - Antje Flieger
- Division of Enteropathogenic Bacteria and Legionella, Robert Koch Institut, Wernigerode, Saxony-Anhalt, 38855, Germany.
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Dextran Sulfate Sodium Colitis Facilitates Colonization with Shiga Toxin-Producing Escherichia coli: a Novel Murine Model for the Study of Shiga Toxicosis. Infect Immun 2018; 86:IAI.00530-18. [PMID: 30150257 DOI: 10.1128/iai.00530-18] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 08/23/2018] [Indexed: 12/23/2022] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) bacteria are globally important gastrointestinal pathogens causing hemorrhagic gastroenteritis with variable progression to potentially fatal Shiga toxicosis. Little is known about the potential effects of E. coli-derived Shiga-like toxins (STXs) on host gastrointestinal immune responses during infection, in part due to the lack of a reproducible immunocompetent-animal model of STEC infection without depleting the commensal microbiota. Here, we describe a novel and reproducible murine model utilizing dextran sulfate sodium (DSS) colitis to induce susceptibility to colonization with clinical-isolate STEC strains. After exposure to DSS and subsequent oral STEC challenge, all the mice were colonized, and 66% of STEC-infected mice required early euthanasia. Morbidity during STEC infection, but not infection with an isogenic STEC mutant with toxin deleted, was associated with increased renal transcripts of the injury markers KIM1 and NGAL, histological evidence of renal tubular injury, and increased renal interleukin 6 gene (IL-6) and CXCL1 inflammatory transcripts. Interestingly, the intestinal burden of STEC during infection was increased compared to its isogenic Shiga toxin deletion strain. Increased bacterial burdens during Shiga toxin production coincided with decreased induction of colonic IL-23 axis transcripts known to be critical for clearance of similar gastrointestinal pathogens in mice, suggesting a previously undescribed role for STEC Shiga toxins in suppressing host immune responses during STEC infection and survival. The DSS+STEC model establishes infection with clinical-isolate strains of STEC in immunocompetent mice without depleting the gastrointestinal microbiota, enabling characterization of the effects of STXs on the IL-23 axis and other gastrointestinal pathogen-host interactions.
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Saile N, Schuh E, Semmler T, Eichhorn I, Wieler LH, Bauwens A, Schmidt H. Determination of virulence and fitness genes associated with the pheU, pheV and selC integration sites of LEE-negative food-borne Shiga toxin-producing Escherichia coli strains. Gut Pathog 2018; 10:43. [PMID: 30337962 PMCID: PMC6174562 DOI: 10.1186/s13099-018-0271-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 10/01/2018] [Indexed: 01/22/2023] Open
Abstract
Background In the current study, nine foodborne “Locus of Enterocyte Effacement” (LEE)-negative Shiga toxin-producing Escherichia coli (STEC) strains were selected for whole genome sequencing and analysis for yet unknown genetic elements within the already known LEE integration sites selC, pheU and pheV. Foreign DNA ranging in size from 3.4 to 57 kbp was detected and further analyzed. Five STEC strains contained an insertion of foreign DNA adjacent to the selC tRNA gene and five and seven strains contained foreign DNA adjacent to the pheU and pheV tRNA genes, respectively. We characterized the foreign DNA insertion associated with selC (STEC O91:H21 strain 17584/1), pheU (STEC O8:H4 strain RF1a and O55:Hnt strain K30) and pheV (STEC O91:H21 strain 17584/1 and O113:H21 strain TS18/08) as examples. Results In total, 293 open reading frames partially encoding putative virulence factors such as TonB-dependent receptors, DNA helicases, a hemolysin activator protein precursor, antigen 43, anti-restriction protein KlcA, ShiA, and phosphoethanolamine transferases were detected. A virulence type IV toxin-antitoxin system was detected in three strains. Additionally, the ato system was found in one strain. In strain 17584/1 we were able to define a new genomic island which we designated GIselC17584/1. The island contained integrases and mobile elements in addition to genes for increased fitness and those playing a putative role in pathogenicity. Conclusion The data presented highlight the important role of the three tRNAs selC, pheU, and pheV for the genomic flexibility of E. coli. Electronic supplementary material The online version of this article (10.1186/s13099-018-0271-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Nadja Saile
- 1Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstr. 28, 70599 Stuttgart, Germany
| | - Elisabeth Schuh
- 1Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstr. 28, 70599 Stuttgart, Germany.,2Department Biological Safety, National Reference Laboratory for Escherichia coli, Federal Institute for Risk Assessment (BfR), Diedersdorfer Weg 1, 12277 Berlin, Germany
| | | | - Inga Eichhorn
- 4Institute of Microbiology and Epizootics, Freie Universität Berlin, Robert-von-Ostertag-Str. 7-13, 14163 Berlin, Germany
| | | | - Andreas Bauwens
- 5Institute for Hygiene, University of Münster, Robert-Koch-Str. 41, 48149 Münster, Germany
| | - Herbert Schmidt
- 1Institute of Food Science and Biotechnology, University of Hohenheim, Garbenstr. 28, 70599 Stuttgart, Germany
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