1
|
Fernández-Yáñez V, Ibaceta V, Torres A, Vidal RM, Schneider I, Schilling V, Toro C, Arellano C, Scavone P, Muñoz I, Del Canto F. Presence and Role of the Type 3 Fimbria in the Adherence Capacity of Enterobacter hormaechei subsp. hoffmannii. Microorganisms 2024; 12:1441. [PMID: 39065209 PMCID: PMC11279048 DOI: 10.3390/microorganisms12071441] [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: 06/17/2024] [Revised: 07/08/2024] [Accepted: 07/10/2024] [Indexed: 07/28/2024] Open
Abstract
Enterobacter hormaechei, one of the species within the Enterobacter cloacae complex, is a relevant agent of healthcare-associated infections. In addition, it has gained relevance because isolates have shown the capacity to resist several antibiotics, particularly carbapenems. However, knowledge regarding colonization and virulence mechanisms of E. hormaechei has not progressed to the same extent as other Enterobacteriaceae species as Escherichia coli or Klebsiella pneumoniae. Here, we describe the presence and role of the type 3 fimbria, a chaperone-usher assembled fimbria, which was first described in Klebsiella spp., and which has been detected in other representatives of the Enterobacteriaceae family. Eight Chilean E. cloacae isolates were examined, and among them, four E. hormaechei isolates were found to produce the type 3 fimbria. These isolates were identified as E. hormaechei subsp. hoffmannii, one of the five subspecies known. A mutant E. hormaechei subsp. hoffmannii strain lacking the mrkA gene, encoding the major structural subunit, displayed a significantly reduced adherence capacity to a plastic surface and to Caco-2 cells, compared to the wild-type strain. This phenotype of reduced adherence capacity was not observed in the mutant strains complemented with the mrkA gene under the control of an inducible promoter. Therefore, these data suggest a role of the type 3 fimbria in the adherence capacity of E. hormaechei subsp. hoffmannii. A screening in E. hormaechei genomes contained in the NCBI RefSeq Assembly database indicated that the overall presence of the type 3 fimbria is uncommon (5.94-7.37%), although genes encoding the structure were detected in representatives of the five E. hormaechei subspecies. Exploration of complete genomes indicates that, in most of the cases, the mrkABCDF locus, encoding the type 3 fimbria, is located in plasmids. Furthermore, sequence types currently found in healthcare-associated infections were found to harbor genes encoding the type 3 fimbria, mainly ST145, ST78, ST118, ST168, ST66, ST93, and ST171. Thus, although the type 3 fimbria is not widespread among the species, it might be a determinant of fitness for a subset of E. hormaechei representatives.
Collapse
Affiliation(s)
- Valentina Fernández-Yáñez
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile, Av. Libertador Bernardo O’Higgins 3363, Santiago 9170022, Chile;
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Av. Independencia 1027, Independencia, Santiago 8380453, Chile
| | - Valentina Ibaceta
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Av. Independencia 1027, Independencia, Santiago 8380453, Chile
| | - Alexia Torres
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Av. Independencia 1027, Independencia, Santiago 8380453, Chile
| | - Roberto M. Vidal
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Av. Independencia 1027, Independencia, Santiago 8380453, Chile
- Instituto Milenio de Inmunología e Inmunoterapia, Facultad de Medicina, Universidad de Chile, Av. Independencia 1027, Independencia, Santiago 8380453, Chile
| | - Isidora Schneider
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Av. Independencia 1027, Independencia, Santiago 8380453, Chile
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago 8380453, Chile
| | - Valeria Schilling
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Av. Independencia 1027, Independencia, Santiago 8380453, Chile
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago 8380453, Chile
| | - Cecilia Toro
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Av. Independencia 1027, Independencia, Santiago 8380453, Chile
| | - Carolina Arellano
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Av. Independencia 1027, Independencia, Santiago 8380453, Chile
| | - Paola Scavone
- Laboratorio de Biofilms Microbianos, Departamento de Microbiología, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo 11600, Uruguay
| | - Ignacio Muñoz
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Av. Independencia 1027, Independencia, Santiago 8380453, Chile
| | - Felipe Del Canto
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Av. Independencia 1027, Independencia, Santiago 8380453, Chile
| |
Collapse
|
2
|
Scheutz F, Nielsen CH, von Mentzer A. Construction of the ETECFinder database for the characterization of enterotoxigenic Escherichia coli (ETEC) and revision of the VirulenceFinder web tool at the CGE website. J Clin Microbiol 2024; 62:e0057023. [PMID: 38656142 PMCID: PMC11237473 DOI: 10.1128/jcm.00570-23] [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: 05/03/2023] [Accepted: 03/05/2024] [Indexed: 04/26/2024] Open
Abstract
The identification of pathogens is essential for effective surveillance and outbreak detection, which lately has been facilitated by the decreasing cost of whole-genome sequencing (WGS). However, extracting relevant virulence genes from WGS data remains a challenge. In this study, we developed a web-based tool to predict virulence-associated genes in enterotoxigenic Escherichia coli (ETEC), which is a major concern for human and animal health. The database includes genes encoding the heat-labile toxin (LT) (eltA and eltB), heat-stable toxin (ST) (est), colonization factors CS1 through 30, F4, F5, F6, F17, F18, and F41, as well as toxigenic invasion and adherence loci (tia, tibAC, etpBAC, eatA, yghJ, and tleA). To construct the database, we revised the existing ETEC nomenclature and used the VirulenceFinder webtool at the CGE website [VirulenceFinder 2.0 (dtu.dk)]. The database was tested on 1,083 preassembled ETEC genomes, two BioProjects (PRJNA421191 with 305 and PRJNA416134 with 134 sequences), and the ETEC reference genome H10407. In total, 455 new virulence gene alleles were added, 50 alleles were replaced or renamed, and two were removed. Overall, our tool has the potential to greatly facilitate ETEC identification and improve the accuracy of WGS analysis. It can also help identify potential new virulence genes in ETEC. The revised nomenclature and expanded gene repertoire provide a better understanding of the genetic diversity of ETEC. Additionally, the user-friendly interface makes it accessible to users with limited bioinformatics experience. IMPORTANCE Detecting colonization factors in enterotoxigenic Escherichia coli (ETEC) is challenging due to their large number, heterogeneity, and lack of standardized tests. Therefore, it is important to include these ETEC-related genes in a more comprehensive VirulenceFinder database in order to obtain a more complete coverage of the virulence gene repertoire of pathogenic types of E. coli. ETEC vaccines are of great importance due to the severity of the infections, primarily in children. A tool such as this could assist in the surveillance of ETEC in order to determine the prevalence of relevant types in different parts of the world, allowing vaccine developers to target the most prevalent types and, thus, a more effective vaccine.
Collapse
Affiliation(s)
- Flemming Scheutz
- The International Escherichia and Klebsiella Centre, Statens Serum Institut, Copenhagen, Denmark
- Department of Bacteria, Parasites and Fungi, Statens Serum Institut, Copenhagen, Denmark
| | - Camilla Hald Nielsen
- The International Escherichia and Klebsiella Centre, Statens Serum Institut, Copenhagen, Denmark
- Department of Bacteria, Parasites and Fungi, Statens Serum Institut, Copenhagen, Denmark
| | - Astrid von Mentzer
- Department of Microbiology and Immunology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| |
Collapse
|
3
|
von Mentzer A, Svennerholm AM. Colonization factors of human and animal-specific enterotoxigenic Escherichia coli (ETEC). Trends Microbiol 2024; 32:448-464. [PMID: 38052687 DOI: 10.1016/j.tim.2023.11.001] [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: 07/11/2023] [Revised: 11/01/2023] [Accepted: 11/07/2023] [Indexed: 12/07/2023]
Abstract
Colonization factors (CFs) are major virulence factors of enterotoxigenic Escherichia coli (ETEC). This pathogen is among the most common causes of bacterial diarrhea in children in low- and middle-income countries, travelers, and livestock. CFs are major candidate antigens in vaccines under development as preventive measures against ETEC infections in humans and livestock. Recent molecular studies have indicated that newly identified CFs on human ETEC are closely related to animal ETEC CFs. Increased knowledge of pathogenic mechanisms, immunogenicity, regulation, and expression of ETEC CFs, as well as the possible spread of animal ETEC to humans, may facilitate the future development of ETEC vaccines for humans and animals. Here, we present an updated review of CFs in ETEC.
Collapse
Affiliation(s)
- Astrid von Mentzer
- Department of Microbiology and Immunology, Sahlgrenska Academy, University of Gothenburg, Sweden; Wellcome Sanger Institute, Hinxton, UK.
| | - Ann-Mari Svennerholm
- Department of Microbiology and Immunology, Sahlgrenska Academy, University of Gothenburg, Sweden
| |
Collapse
|
4
|
Pajuelo MJ, Noazin S, Cabrera L, Toledo A, Velagic M, Arias L, Ochoa M, Moulton LH, Saito M, Gilman RH, Chakraborty S. Epidemiology of enterotoxigenic Escherichia coli and impact on the growth of children in the first two years of life in Lima, Peru. Front Public Health 2024; 12:1332319. [PMID: 38584932 PMCID: PMC10995271 DOI: 10.3389/fpubh.2024.1332319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 03/11/2024] [Indexed: 04/09/2024] Open
Abstract
Background Enterotoxigenic E. coli (ETEC) is a leading cause of diarrheal morbidity and mortality in children, although the data on disease burden, epidemiology, and impact on health at the community level are limited. Methods In a longitudinal birth cohort study of 345 children followed until 24 months of age in Lima, Peru, we measured ETEC burden in diarrheal and non-diarrheal samples using quantitative PCR (LT, STh, and STp toxin genes), studied epidemiology and measured anthropometry in children. Results About 70% of children suffered from one or more ETEC diarrhea episodes. Overall, the ETEC incidence rate (IR) was 73 per 100 child-years. ETEC infections began early after birth causing 10% (8.9-11.1) ETEC-attributable diarrheal burden at the population level (PAF) in neonates and most of the infections (58%) were attributed to ST-ETEC [PAF 7.9% (1.9-13.5)] and LT + ST-ETEC (29%) of which all the episodes were associated with diarrhea. ETEC infections increased with age, peaking at 17% PAF (4.6-27.7%; p = 0.026) at 21 to 24 months. ST-ETEC was the most prevalent type (IR 32.1) with frequent serial infections in a child. The common colonization factors in ETEC diarrhea cases were CFA/I, CS12, CS21, CS3, and CS6, while in asymptomatic ETEC cases were CS12, CS6 and CS21. Only few (5.7%) children had repeated infections with the same combination of ETEC toxin(s) and CFs, suggested genotype-specific immunity from each infection. For an average ETEC diarrhea episode of 5 days, reductions of 0.060 weight-for-length z-score (0.007 to 0.114; p = 0.027) and 0.061 weight-for-age z-score (0.015 to 0.108; p = 0.009) were noted in the following 30 days. Conclusion This study showed that ETEC is a significant pathogen in Peruvian children who experience serial infections with multiple age-specific pathotypes, resulting in transitory growth impairment.
Collapse
Affiliation(s)
- Monica J. Pajuelo
- Laboratorio Microbiología Molecular – Laboratorios de Investigación y Desarrollo, Facultad de Ciencias e Ingeniería, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Sassan Noazin
- Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | | | - Angie Toledo
- Laboratorio Microbiología Molecular – Laboratorios de Investigación y Desarrollo, Facultad de Ciencias e Ingeniería, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Mirza Velagic
- Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | - Lucero Arias
- Laboratorio Microbiología Molecular – Laboratorios de Investigación y Desarrollo, Facultad de Ciencias e Ingeniería, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Mayra Ochoa
- Laboratorio Microbiología Molecular – Laboratorios de Investigación y Desarrollo, Facultad de Ciencias e Ingeniería, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Lawrence H. Moulton
- Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | - Mayuko Saito
- Department of Virology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Robert H. Gilman
- Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| | - Subhra Chakraborty
- Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, United States
| |
Collapse
|
5
|
Calderon Toledo C, von Mentzer A, Agramont J, Thorell K, Zhou Y, Szabó M, Colque P, Kuhn I, Gutiérrez-Cortez S, Joffré E. Circulation of enterotoxigenic Escherichia coli (ETEC) isolates expressing CS23 from the environment to clinical settings. mSystems 2023; 8:e0014123. [PMID: 37681982 PMCID: PMC10654058 DOI: 10.1128/msystems.00141-23] [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: 02/08/2023] [Accepted: 06/27/2023] [Indexed: 09/09/2023] Open
Abstract
IMPORTANCE The importance of clean water cannot be overstated. It is a vital resource for maintaining health and well-being. Unfortunately, water sources contaminated with fecal discharges from animal and human origin due to a lack of wastewater management pose a significant risk to communities, as they can become a means of transmission of pathogenic bacteria like enterotoxigenic E. coli (ETEC). ETEC is frequently found in polluted water in countries with a high prevalence of diarrheal diseases, such as Bolivia. This study provides novel insights into the circulation of ETEC between diarrheal cases and polluted water sources in areas with high rates of diarrheal disease. These findings highlight the Choqueyapu River as a potential reservoir for emerging pathogens carrying antibiotic-resistance genes, making it a crucial area for monitoring and intervention. Furthermore, the results demonstrate the feasibility of a low-cost, high-throughput method for tracking bacterial pathogens in low- and middle-income countries, making it a valuable tool for One Health monitoring efforts.
Collapse
Affiliation(s)
- Carla Calderon Toledo
- Unidad de Microbiología Ambiental, Instituto de Biología Molecular y Biotecnología (IBMB), Carrera de Biología, Universidad Mayor de San Andrés, La Paz, Bolivia
| | - Astrid von Mentzer
- Wellcome Sanger Institute, Hinxton, Cambridge, United Kingdom
- Department of Microbiology and Immunology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
- Mathematical Sciences, Chalmers University of Technology, Gothenburg, Sweden
| | - Jorge Agramont
- Unidad de Microbiología Ambiental, Instituto de Biología Molecular y Biotecnología (IBMB), Carrera de Biología, Universidad Mayor de San Andrés, La Paz, Bolivia
| | - Kaisa Thorell
- Department of Chemistry and Molecular Biology (CMB), University of Gothenburg, Gothenburg, Sweden
| | - Yingshun Zhou
- Department of Pathogen Biology, The public platform of the Pathogen Biology, School of Basic Medicine, Southwest Medical University, Luzhou, Sichuan, China
| | - Miklós Szabó
- Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Stockholm, Sweden
| | - Patricia Colque
- Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Stockholm, Sweden
| | - Inger Kuhn
- Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Stockholm, Sweden
| | - Sergio Gutiérrez-Cortez
- Unidad de Microbiología Ambiental, Instituto de Biología Molecular y Biotecnología (IBMB), Carrera de Biología, Universidad Mayor de San Andrés, La Paz, Bolivia
| | - Enrique Joffré
- Department of Microbiology, Tumor and Cell Biology (MTC), Karolinska Institutet, Stockholm, Sweden
| |
Collapse
|
6
|
Bagel A, Lopez C, David-Briand E, Michel V, Douëllou T, Sergentet D. Serotype-dependent adhesion of Shiga toxin-producing Escherichia coli to bovine milk fat globule membrane proteins. Front Microbiol 2022; 13:1010665. [PMID: 36504830 PMCID: PMC9731836 DOI: 10.3389/fmicb.2022.1010665] [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: 08/03/2022] [Accepted: 10/10/2022] [Indexed: 11/25/2022] Open
Abstract
Shiga toxin-producing Escherichia coli (STEC) are food-borne pathogens that can cause severe symptoms for humans. Raw milk products are often incriminated as vehicule for human STEC infection. However, raw milk naturally contains molecules, such as the milk fat globule membrane and associated proteins, that could inhibit pathogen adhesion by acting as mimetic ligands. This study aimed to: (i) evaluate the capability of STEC cells to adhere to bovine milk fat globule membrane proteins (MFGMPs), (ii) highlight STEC surface proteins associated with adhesion and (iii) evaluate the variation between different STEC serotypes. We evaluated the physicochemical interactions between STEC and milk fat globules (MFGs) by analyzing hydrophobic properties and measuring the ζ-potential. We used a plate adhesion assay to assess adhesion between MFGMPs and 15 Escherichia coli strains belonging to three key serotypes (O157:H7, O26:H11, and O103:H2). A relative quantitative proteomic approach was conducted by mass spectrometry to identify STEC surface proteins that may be involved in STEC-MFG adhesion. The majority of E. coli strains showed a hydrophilic profile. The ζ-potential values were between -3.7 and - 2.9 mV for the strains and between -12.2 ± 0.14 mV for MFGs. Our results suggest that non-specific interactions are not strongly involved in STEC-MFG association and that molecular bonds could form between STEC and MFGs. Plate adhesion assays showed a weak adhesion of O157:H7 E. coli strains to MFGMPs. In contrast, O26:H11 and O103:H2 serotypes attached more to MFGMPs. Relative quantitative proteomic analysis showed that the O26:H11 str. 21,765 differentially expressed five outer membrane-associated proteins or lipoproteins compared with the O157:H7 str. EDL933. This analysis also found strain-specific differentially expressed proteins, including four O26:H11 str. 21,765-specific proteins/lipoproteins and eight O103:H2 str. PMK5-specific proteins. For the first time, we demonstrated STEC adhesion to MFGMPs and discovered a serotype effect. Several outer membrane proteins-OmpC and homologous proteins, intimin, Type 1 Fimbriae, and AIDA-I-that may be involved in STEC-MFG adhesion were highlighted. More research on STEC's ability to adhere to MFGMs in diverse biological environments, such as raw milk cheeses and the human gastrointestinal tract, is needed to confirm the anti-adhesion properties of the STEC-MFG complex.
Collapse
Affiliation(s)
- Arthur Bagel
- Bacterial Opportunistic Pathogens and Environment Research Group, UMR5557 Ecologie Microbienne Lyon, National Center of Scientific Research (CNRS), Université de Lyon, Marcy-l’Etoile, France
| | | | | | | | - Thomas Douëllou
- Bacterial Opportunistic Pathogens and Environment Research Group, UMR5557 Ecologie Microbienne Lyon, National Center of Scientific Research (CNRS), Université de Lyon, Marcy-l’Etoile, France
| | - Delphine Sergentet
- Bacterial Opportunistic Pathogens and Environment Research Group, UMR5557 Ecologie Microbienne Lyon, National Center of Scientific Research (CNRS), Université de Lyon, Marcy-l’Etoile, France,Laboratoire d’Etudes des Microorganismes Alimentaires Pathogènes, VetAgro Sup—Campus Vétérinaire, French National Reference Laboratory for Escherichia coli Including Shiga Toxin-Producing E. coli (NRL-STEC), Université de Lyon, Marcy-l‘Etoile, France,*Correspondence: Delphine Sergentet,
| |
Collapse
|
7
|
Zhang Y, Tan P, Zhao Y, Ma X. Enterotoxigenic Escherichia coli: intestinal pathogenesis mechanisms and colonization resistance by gut microbiota. Gut Microbes 2022; 14:2055943. [PMID: 35358002 PMCID: PMC8973357 DOI: 10.1080/19490976.2022.2055943] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) is a major cause of diarrhea in children and travelers in developing countries. ETEC is characterized by the ability to produce major virulence factors including colonization factors (CFs) and enterotoxins, that bind to specific receptors on epithelial cells and induce diarrhea. The gut microbiota is a stable and sophisticated ecosystem that performs a range of beneficial functions for the host, including protection against pathogen colonization. Understanding the pathogenic mechanisms of ETEC and the interaction between the gut microbiota and ETEC represents not only a research need but also an opportunity and challenge to develop precautions for ETEC infection. Herein, this review focuses on recent discoveries about ETEC etiology, pathogenesis and clinical manifestation, and discusses the colonization resistances mediated by gut microbiota, as well as preventative strategies against ETEC with an aim to provide novel insights that can reduce the adverse effect on human health.
Collapse
Affiliation(s)
- Yucheng Zhang
- State Key Laboratory of Animal Nutrition, Department of Animal Nutrition and Feed Science, China Agricultural University, Beijing, China
| | - Peng Tan
- State Key Laboratory of Animal Nutrition, Department of Animal Nutrition and Feed Science, China Agricultural University, Beijing, China
| | - Ying Zhao
- State Key Laboratory of Animal Nutrition, Department of Animal Nutrition and Feed Science, China Agricultural University, Beijing, China
| | - Xi Ma
- State Key Laboratory of Animal Nutrition, Department of Animal Nutrition and Feed Science, China Agricultural University, Beijing, China,CONTACT Xi Ma State Key Laboratory of Animal Nutrition, Department of Animal Nutrition and Feed Science, China Agricultural University, Beijing, China
| |
Collapse
|
8
|
Mondal I, Bhakat D, Chowdhury G, Manna A, Samanta S, Deb AK, Mukhopadhyay AK, Chatterjee NS. Distribution of virulence factors and its relatedness towards the antimicrobial response of enterotoxigenic Escherichia coli strains isolated from patients in Kolkata, India. J Appl Microbiol 2021; 132:675-686. [PMID: 34242448 DOI: 10.1111/jam.15206] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 06/11/2021] [Accepted: 06/29/2021] [Indexed: 12/14/2022]
Abstract
AIM Enterotoxigenic Escherichia coli (ETEC) is one of the most widely recognized diarrhoeal pathogens in developing countries. The advancement of ETEC vaccine development depends on the antigenic determinants of the ETEC isolates from a particular geographical region. So, the aim here was to comprehend the distribution of virulence determinants of the clinical ETEC strains of this region. Additionally, an attempt was made to find any correlation with the antimicrobial response pattern. METHODS AND RESULTS Multiplex PCR was employed to identify virulence determinants followed by confirmatory singleplex PCR. For observation of antibiotic response, the Kirby-Bauer method was used. Out of 379 strains, 46% of strains harboured both the enterotoxins ST and LT, whereas 15% were LT only. Among the major colonization factors (CFs), CS6 (41%) was the most prevalent followed by CFA/I (35%) and CFA/III was the lowest (3%). Among the minor CFs, CS21 (25%) was most prevalent, while CS15 showed the lowest (3%) presence. Among the non-classical virulence factors, EatA (69%) was predominant. ETEC strains harbouring CS6 showed resistance towards the commonly used drug Ciprofloxacin (70%). CONCLUSION CS6 and elt+est toxin genes co-occurred covering 51% of the isolates. CS21 was found in most strains with est genes (43%). EatA was found to occur frequently when ST was present alone or with LT. CS6-harbouring strains showed an independent correlation to antimicrobial resistance. SIGNIFICANCE AND IMPACT OF THE STUDY This study would aid in identifying the commonly circulating ETEC isolates of Kolkata, India, and their prevalent virulence determinants. Knowledge of antibiotic resistance patterns would also help in the appropriate use of antibiotics. Furthermore, the study would aid in identifying the multivalent antigens suitable for region-specific ETEC vaccines with maximum coverage.
Collapse
Affiliation(s)
- Indranil Mondal
- Division of Biochemistry, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Debjyoti Bhakat
- Division of Biochemistry, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Goutam Chowdhury
- Division of Bacteriology, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Asis Manna
- Infectious Diseases and Beliaghata General Hospital, Kolkata, India
| | - Sandip Samanta
- Dr. B.C.Roy Post Graduate Institute of Pediatric Sciences, Kolkata, India
| | - Alok Kumar Deb
- Division of Epidemiology, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Asish Kumar Mukhopadhyay
- Division of Bacteriology, ICMR-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | | |
Collapse
|
9
|
Velásquez F, Marín-Rojas J, Soto-Rifo R, Torres A, Del Canto F, Valiente-Echeverría F. Escherichia coli HS and Enterotoxigenic Escherichia coli Hinder Stress Granule Assembly. Microorganisms 2020; 9:microorganisms9010017. [PMID: 33374562 PMCID: PMC7822485 DOI: 10.3390/microorganisms9010017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 12/15/2020] [Accepted: 12/17/2020] [Indexed: 12/12/2022] Open
Abstract
Escherichia coli, one of the most abundant bacterial species in the human gut microbiota, has developed a mutualistic relationship with its host, regulating immunological responses. In contrast, enterotoxigenic E. coli (ETEC), one of the main etiologic agents of diarrheal morbidity and mortality in children under the age of five in developing countries, has developed mechanisms to reduce the immune-activator effect to carry out a successful infection. Following infection, the host cell initiates the shutting-off of protein synthesis and stress granule (SG) assembly. This is mostly mediated by the phosphorylation of translation initiator factor 2α (eIF2α). We therefore evaluated the ability of a non-pathogenic E. coli strain (E. coli HS) and an ETEC strain (ETEC 1766a) to induce stress granule assembly, even in response to exogenous stresses. In this work, we found that infection with E. coli HS or ETEC 1766a prevents SG assembly in Caco-2 cells treated with sodium arsenite (Ars) after infection. We also show that this effect occurs through an eIF2α phosphorylation (eIF2α-P)-dependent mechanism. Understanding how bacteria counters host stress responses will lay the groundwork for new therapeutic strategies to bolster host cell immune defenses against these pathogens.
Collapse
Affiliation(s)
- Felipe Velásquez
- Molecular and Cellular Virology Laboratory, Virology Program, Faculty of Medicine, Institute of Biomedical Sciences, Universidad de Chile, 8380453 Santiago, Chile; (F.V.); (J.M.-R.); (R.S.-R.)
- HIV/AIDS Workgroup, Faculty of Medicine, Universidad de Chile, 8380453 Santiago, Chile
| | - Josefina Marín-Rojas
- Molecular and Cellular Virology Laboratory, Virology Program, Faculty of Medicine, Institute of Biomedical Sciences, Universidad de Chile, 8380453 Santiago, Chile; (F.V.); (J.M.-R.); (R.S.-R.)
- HIV/AIDS Workgroup, Faculty of Medicine, Universidad de Chile, 8380453 Santiago, Chile
| | - Ricardo Soto-Rifo
- Molecular and Cellular Virology Laboratory, Virology Program, Faculty of Medicine, Institute of Biomedical Sciences, Universidad de Chile, 8380453 Santiago, Chile; (F.V.); (J.M.-R.); (R.S.-R.)
- HIV/AIDS Workgroup, Faculty of Medicine, Universidad de Chile, 8380453 Santiago, Chile
| | - Alexia Torres
- Microbiology and Mycology Program, Faculty of Medicine, Institute of Biomedical Sciences, Universidad de Chile, 8380453 Santiago, Chile; (A.T.); (F.D.C.)
| | - Felipe Del Canto
- Microbiology and Mycology Program, Faculty of Medicine, Institute of Biomedical Sciences, Universidad de Chile, 8380453 Santiago, Chile; (A.T.); (F.D.C.)
| | - Fernando Valiente-Echeverría
- Molecular and Cellular Virology Laboratory, Virology Program, Faculty of Medicine, Institute of Biomedical Sciences, Universidad de Chile, 8380453 Santiago, Chile; (F.V.); (J.M.-R.); (R.S.-R.)
- HIV/AIDS Workgroup, Faculty of Medicine, Universidad de Chile, 8380453 Santiago, Chile
- Correspondence:
| |
Collapse
|
10
|
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.
Collapse
|
11
|
Chakraborty S, Brubaker J, Harro C, Weirzba T, Sack D. Development of a novel multiplex electrochemiluminescent-based immunoassay to aid enterotoxigenic Escherichia coli vaccine development and evaluations. J Immunol Methods 2019; 470:6-14. [PMID: 31004579 PMCID: PMC6538825 DOI: 10.1016/j.jim.2019.04.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 03/10/2019] [Accepted: 04/16/2019] [Indexed: 12/30/2022]
Abstract
Enterotoxigenic Escherichia coli (ETEC) is a leading cause of bacterial diarrhea both among children in low and middle income countries and in travelers to these regions. Although there are several approaches to develop an effective vaccine for ETEC, no licensed vaccines are currently available. The most advanced ETEC vaccine candidates include multiple colonization factors along with the heat labile toxin B subunit. In the absence of known correlates of protection, and to understand the mechanism of protection, monitoring immune responses to a majority of the vaccine associated antigens using various types of samples is needed. Unfortunately, a traditional ELISA is time consuming, labor intensive and requires substantial amounts of antigens and sample volumes. To address these constraints, we developed and validated a novel high throughput electrochemiluminescent (ECL) - based multiplex immunoassay using Meso Scale Discovery (MSD) platform for analyzing immune responses to ETEC antigens. The ETEC multiplex ECL assay is an 8-plex assay which includes the ETEC colonization factor antigens (CFA/I, CS1, CS2, CS3, CS5 and CS6) along with the two subunits of heat labile toxin (LTA and LTB). Our data suggested that a single dilution of sample provides a quantifiable result for a wide range of sample titers. To compare ETEC multiplex ECL with ELISA, we carried out assays using the same antigens with the two immunoassay platforms using a common sample set of serum and ALS (antibodies in lymphocyte supernatant) specimens. The MSD platform achieved excellent correlations with ELISA for the antigens tested, consistently detecting comparable antibody levels in the samples. The ETEC multiplex ECL can serve as a fundamental platform in evaluating performances of candidate ETEC vaccines in future field trials. A novel ETEC multiplex ECL assay was developed which achieved excellent correlations with conventional ELISA. ETEC multiplex ECL assay would minimize volumes of samples and antigens as well as save time and labor. The ETEC multiplex assay could serve as an improved platform for evaluation of candidate ETEC vaccines.
Collapse
Affiliation(s)
- Subhra Chakraborty
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
| | - Jessica Brubaker
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Clayton Harro
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | | | - David Sack
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| |
Collapse
|
12
|
The bile salt glycocholate induces global changes in gene and protein expression and activates virulence in enterotoxigenic Escherichia coli. Sci Rep 2019; 9:108. [PMID: 30643184 PMCID: PMC6331568 DOI: 10.1038/s41598-018-36414-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 11/20/2018] [Indexed: 12/23/2022] Open
Abstract
Pathogenic bacteria use specific host factors to modulate virulence and stress responses during infection. We found previously that the host factor bile and the bile component glyco-conjugated cholate (NaGCH, sodium glycocholate) upregulate the colonization factor CS5 in enterotoxigenic Escherichia coli (ETEC). To further understand the global regulatory effects of bile and NaGCH, we performed Illumina RNA-Seq and found that crude bile and NaGCH altered the expression of 61 genes in CS5 + CS6 ETEC isolates. The most striking finding was high induction of the CS5 operon (csfA-F), its putative transcription factor csvR, and the putative ETEC virulence factor cexE. iTRAQ-coupled LC-MS/MS proteomic analyses verified induction of the plasmid-borne virulence proteins CS5 and CexE and also showed that NaGCH affected the expression of bacterial membrane proteins. Furthermore, NaGCH induced bacteria to aggregate, increased their adherence to epithelial cells, and reduced their motility. Our results indicate that CS5 + CS6 ETEC use NaGCH present in the small intestine as a signal to initiate colonization of the epithelium.
Collapse
|
13
|
Vidal RM, Muhsen K, Tennant SM, Svennerholm AM, Sow SO, Sur D, Zaidi AKM, Faruque ASG, Saha D, Adegbola R, Hossain MJ, Alonso PL, Breiman RF, Bassat Q, Tamboura B, Sanogo D, Onwuchekwa U, Manna B, Ramamurthy T, Kanungo S, Ahmed S, Qureshi S, Quadri F, Hossain A, Das SK, Antonio M, Mandomando I, Nhampossa T, Acácio S, Omore R, Ochieng JB, Oundo JO, Mintz ED, O’Reilly CE, Berkeley LY, Livio S, Panchalingam S, Nasrin D, Farag TH, Wu Y, Sommerfelt H, Robins-Browne RM, Del Canto F, Hazen TH, Rasko DA, Kotloff KL, Nataro JP, Levine MM. Colonization factors among enterotoxigenic Escherichia coli isolates from children with moderate-to-severe diarrhea and from matched controls in the Global Enteric Multicenter Study (GEMS). PLoS Negl Trop Dis 2019; 13:e0007037. [PMID: 30608930 PMCID: PMC6343939 DOI: 10.1371/journal.pntd.0007037] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 01/23/2019] [Accepted: 11/28/2018] [Indexed: 12/29/2022] Open
Abstract
Background Enterotoxigenic Escherichia coli (ETEC) encoding heat-stable enterotoxin (ST) alone or with heat-labile enterotoxin (LT) cause moderate-to-severe diarrhea (MSD) in developing country children. The Global Enteric Multicenter Study (GEMS) identified ETEC encoding ST among the top four enteropathogens. Since the GEMS objective was to provide evidence to guide development and implementation of enteric vaccines and other interventions to diminish diarrheal disease morbidity and mortality, we examined colonization factor (CF) prevalence among ETEC isolates from children age <5 years with MSD and from matched controls in four African and three Asian sites. We also assessed strength of association of specific CFs with MSD. Methodology/Principal findings MSD cases enrolled at healthcare facilities over three years and matched controls were tested in a standardized manner for many enteropathogens. To identify ETEC, three E. coli colonies per child were tested by polymerase chain reaction (PCR) to detect genes encoding LT, ST; confirmed ETEC were examined by PCR for major CFs (Colonization Factor Antigen I [CFA/I] or Coli Surface [CS] antigens CS1-CS6) and minor CFs (CS7, CS12, CS13, CS14, CS17, CS18, CS19, CS20, CS21, CS30). ETEC from 806 cases had a single toxin/CF profile in three tested strains per child. Major CFs, components of multiple ETEC vaccine candidates, were detected in 66.0% of LT/ST and ST-only cases and were associated with MSD versus matched controls by conditional logistic regression (p≤0.006); major CFs detected in only 25.0% of LT-only cases weren’t associated with MSD. ETEC encoding exclusively CS14, identified among 19.9% of 291 ST-only and 1.5% of 259 LT/ST strains, were associated with MSD (p = 0.0011). No other minor CF exhibited prevalence ≥5% and significant association with MSD. Conclusions/Significance Major CF-based efficacious ETEC vaccines could potentially prevent up to 66% of pediatric MSD cases due to ST-encoding ETEC in developing countries; adding CS14 extends coverage to ~77%. Enterotoxigenic Escherichia coli (“ETEC”) were found to be one of the four most consistently important agents that cause moderate-to-severe diarrhea among children <5 years of age in a large case-control study, the Global Enteric Multicenter Study, performed in four countries in sub-Saharan Africa and three in South Asia. ETEC attach to the lining of the human small intestine by means of protein colonization factors (CFs), after which bacterial toxins stimulate intestinal secretion resulting in diarrhea. Moderate-to-severe diarrhea in young children in developing countries can lead to malnutrition and death. Vaccines are being developed to prevent ETEC diarrhea and its consequences. Several ETEC vaccines aim to stimulate antibodies (protective proteins) that will bind CFs and prevent the bacteria from attaching to intestinal cells, which should, in turn, prevent ETEC diarrhea. Different types of CFs exist. To guide the development of vaccines intending to provide broad protection against ETEC, one must know the frequency with which the different major CFs are produced by ETEC. This paper reports an extensive systematic survey of ETEC CFs and provides helpful information to guide the development of ETEC vaccines.
Collapse
Affiliation(s)
- Roberto M. Vidal
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Khitam Muhsen
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Sharon M. Tennant
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Ann-Mari Svennerholm
- Department of Microbiology and Immunology at Institute of Biomedicine, University of Göteborg, Göteborg, Sweden
| | - Samba O. Sow
- Centre pour le Développement des Vaccins du Mali (CVD-Mali), Bamako, Mali
| | - Dipika Sur
- National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Anita K. M. Zaidi
- Department of Paediatrics and Child Health, the Aga Khan University, Karachi, Pakistan
| | - Abu S. G. Faruque
- International Centre for Diarrhoeal Disease Research, Mohakhali, Dhaka, Bangladesh
| | - Debasish Saha
- Medical Research Council (United Kingdom) Unit, Fajara, The Gambia
| | - Richard Adegbola
- Medical Research Council (United Kingdom) Unit, Fajara, The Gambia
| | | | - Pedro L. Alonso
- Centro de Investigação em Saúde da Manhiça, Maputo, Mozambique
- ISGlobal, Barcelona Ctr. Int. Health Res. Hospital Clínic—Universitat de Barcelona, Barcelona, Spain
| | - Robert F. Breiman
- Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya
- Global Disease Detection Division, Kenya Office of the US Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Quique Bassat
- Centro de Investigação em Saúde da Manhiça, Maputo, Mozambique
- ISGlobal, Barcelona Ctr. Int. Health Res. Hospital Clínic—Universitat de Barcelona, Barcelona, Spain
| | - Boubou Tamboura
- Centre pour le Développement des Vaccins du Mali (CVD-Mali), Bamako, Mali
| | - Doh Sanogo
- Centre pour le Développement des Vaccins du Mali (CVD-Mali), Bamako, Mali
| | - Uma Onwuchekwa
- Centre pour le Développement des Vaccins du Mali (CVD-Mali), Bamako, Mali
| | - Byomkesh Manna
- National Institute of Cholera and Enteric Diseases, Kolkata, India
| | | | - Suman Kanungo
- National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Shahnawaz Ahmed
- International Centre for Diarrhoeal Disease Research, Mohakhali, Dhaka, Bangladesh
| | - Shahida Qureshi
- Department of Paediatrics and Child Health, the Aga Khan University, Karachi, Pakistan
| | - Farheen Quadri
- Department of Paediatrics and Child Health, the Aga Khan University, Karachi, Pakistan
| | - Anowar Hossain
- International Centre for Diarrhoeal Disease Research, Mohakhali, Dhaka, Bangladesh
| | - Sumon K. Das
- International Centre for Diarrhoeal Disease Research, Mohakhali, Dhaka, Bangladesh
| | - Martin Antonio
- Medical Research Council (United Kingdom) Unit, Fajara, The Gambia
| | | | | | - Sozinho Acácio
- Centro de Investigação em Saúde da Manhiça, Maputo, Mozambique
| | - Richard Omore
- Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya
| | - John B. Ochieng
- Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya
| | - Joseph O. Oundo
- Kenya Medical Research Institute/Centers for Disease Control and Prevention, Kisumu, Kenya
| | - Eric D. Mintz
- Division of Foodborne, Waterborne and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Ciara E. O’Reilly
- Division of Foodborne, Waterborne and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Lynette Y. Berkeley
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Sofie Livio
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Sandra Panchalingam
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Dilruba Nasrin
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Tamer H. Farag
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Yukun Wu
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Halvor Sommerfelt
- Centre of Intervention Science in Maternal and Child Health, Centre for International Health, Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway
- Norwegian Institute of Public Health, Oslo, Norway
| | - Roy M. Robins-Browne
- Department of Microbiology and Immunology, Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Victoria, Australia
| | - Felipe Del Canto
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Tracy H. Hazen
- The Institute of Genomic Sciences, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - David A. Rasko
- The Institute of Genomic Sciences, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Karen L. Kotloff
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - James P. Nataro
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Myron M. Levine
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, MD, United States of America
- * E-mail:
| |
Collapse
|
14
|
Derakhshan S, Farhadifar F, Roshani D, Ahmadi A, Haghi F. Study on the presence of resistant diarrheagenic pathotypes in Escherichia coli isolated from patients with urinary tract infection. GASTROENTEROLOGY AND HEPATOLOGY FROM BED TO BENCH 2019; 12:348-357. [PMID: 31749924 PMCID: PMC6820833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 09/18/2019] [Indexed: 06/10/2023]
Abstract
AIM This article aimed to analyze the diarrheagenic potential of E. coli isolated from urinary tract infection (UTI) and to recognize the presence of antibiotic resistance genes. BACKGROUND The marked genome plasticity of Escherichia coli has allowed the emergence of resistant pathogenic strains displaying an unusual arrangement of genes. METHODS In this cross-sectional study, 110 E. coli were isolated from patients with the symptoms of UTI in Sanandaj, west of Iran between July and September - 2015. The isolates were examined by the disk diffusion method for antibiotic susceptibility test and by polymerase chain reaction for the presence of genes characteristic of diarrheagenic E. coli (DEC), Uropathogenic E. coli (UPEC) virulence genes, extended-spectrum β-lactamase bla CTX-M and plasmid-mediated quinolone resistance determinants, qnrA, qnrB, and qnrS. RESULTS The most and the least effective antibiotics were nitrofurantoin and cefotaxime (96.4% and 27.3% sensitivity, respectively). Of the 110 UTI isolates, 57.3% carried diarrheagenic genes. The bundle-forming pilus bfpA was the most prevalent diarrheagenic gene (39.1%). The most commonly detected DEC pathotype was enterotoxigenic E. coli (-ETEC, 12.7%). All the pathotypes carried the bla CTX-M and qnr. The -UPEC hly hemolysin and pap adhesin genes were mainly detected among ETEC isolates. CONCLUSION Our results indicated the presence of resistant diarrheagenic pathotypes in UTI-associated E. coli. Such isolates may have the capacity of causing both extraintestinal and intestinal infections. Based on our knowledge, this is the first report of the presence of qnr in ETEC from urine.
Collapse
Affiliation(s)
- Safoura Derakhshan
- Liver and Digestive Research Center, Research Institute for Health Development, Kurdistan University of Medical Sciences, Sanandaj, Iran
- Zoonoses Research Center, Research Institute for Health Development, Kurdistan University of Medical Sciences, Sanandaj, Iran
| | - Fariba Farhadifar
- Social Determinants of Health Research Center, Research Institute for Health Development, Kurdistan University of Medical Sciences, Sanandaj, Iran
| | - Daem Roshani
- Social Determinants of Health Research Center, Research Institute for Health Development, Kurdistan University of Medical Sciences, Sanandaj, Iran
| | - Amjad Ahmadi
- Department of Microbiology, Faculty of Medicine, Kurdistan University of Medical Sciences, Sanandaj, Iran.
| | - Fakhri Haghi
- Department of Microbiology and Immunology, Faculty of Medical Sciences, Zanjan University of Medical Sciences, Zanjan, Iran
| |
Collapse
|
15
|
Bhakat D, Debnath A, Naik R, Chowdhury G, Deb A, Mukhopadhyay A, Chatterjee N. Identification of common virulence factors present in enterotoxigenicEscherichia coliisolated from diarrhoeal patients in Kolkata, India. J Appl Microbiol 2018; 126:255-265. [DOI: 10.1111/jam.14090] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 07/17/2018] [Accepted: 08/23/2018] [Indexed: 12/25/2022]
Affiliation(s)
- D. Bhakat
- Division of Biochemistry; ICMR-National Institute of Cholera and Enteric Diseases; Kolkata India
| | - A. Debnath
- Division of Biochemistry; ICMR-National Institute of Cholera and Enteric Diseases; Kolkata India
| | - R. Naik
- Division of Biochemistry; ICMR-National Institute of Cholera and Enteric Diseases; Kolkata India
| | - G. Chowdhury
- Division of Bacteriology; ICMR-National Institute of Cholera and Enteric Diseases; Kolkata India
| | - A.K. Deb
- Division of Epidemiology; ICMR-National Institute of Cholera and Enteric Diseases; Kolkata India
| | - A.K. Mukhopadhyay
- Division of Bacteriology; ICMR-National Institute of Cholera and Enteric Diseases; Kolkata India
| | - N.S. Chatterjee
- Division of Biochemistry; ICMR-National Institute of Cholera and Enteric Diseases; Kolkata India
| |
Collapse
|
16
|
Mechanistic insights into the host-microbe interaction and pathogen exclusion mediated by the Mucus-binding protein of Lactobacillus plantarum. Sci Rep 2018; 8:14198. [PMID: 30242281 PMCID: PMC6155027 DOI: 10.1038/s41598-018-32417-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 09/07/2018] [Indexed: 12/11/2022] Open
Abstract
Surface adhesins of pathogens and probiotics strains are implicated in mediating the binding of microbes to host. Mucus-binding protein (Mub) is unique to gut inhabiting lactic acid bacteria; however, the precise role of Mub proteins or its structural domains in host-microbial interaction is not well understood. Last two domains (Mubs5s6) of the six mucus-binding domains arranged in tandem at the C-terminus of the Lp_1643 protein of Lactobacillus plantarum was expressed in E. coli. Mubs5s6 showed binding with the rat intestinal mucus, pig gastric mucins and human intestinal tissues. Preincubation of Mubs5s6 with the Caco-2 and HT-29 cell lines inhibited the binding of pathogenic enterotoxigenic E. coli cells to the enterocytes by 68% and 81%, respectively. Pull-down assay suggested Mubs5s6 binding to the host mucosa components like cytokeratins, Hsp90 and Laminin. Mubs5s6 was predicted to possess calcium and glucose binding sites. Binding of Mubs5s6 with these ligands was also experimentally observed. These ligands are known to be associated with pathogenesis suggesting Mub might negotiate pathogens in multiple ways. To study the feasibility of Mubs5s6 delivery in the gut, it was encapsulated in chitosan-sodium tripolyphosphate microspheres with an efficiency of 65% and release up to 85% in near neutral pH zone over a period of 20 hours. Our results show that Mub plays an important role in the host-microbial cross-talk and possesses the potential for pathogen exclusion to a greater extent than mediated by L. plantarum cells. The functional and technological characteristics of Mubs5s6 make it suitable for breaking the host-pathogen interaction.
Collapse
|
17
|
Werneburg GT, Thanassi DG. Pili Assembled by the Chaperone/Usher Pathway in Escherichia coli and Salmonella. EcoSal Plus 2018; 8:10.1128/ecosalplus.ESP-0007-2017. [PMID: 29536829 PMCID: PMC5940347 DOI: 10.1128/ecosalplus.esp-0007-2017] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Indexed: 12/12/2022]
Abstract
Gram-negative bacteria assemble a variety of surface structures, including the hair-like organelles known as pili or fimbriae. Pili typically function in adhesion and mediate interactions with various surfaces, with other bacteria, and with other types of cells such as host cells. The chaperone/usher (CU) pathway assembles a widespread class of adhesive and virulence-associated pili. Pilus biogenesis by the CU pathway requires a dedicated periplasmic chaperone and integral outer membrane protein termed the usher, which forms a multifunctional assembly and secretion platform. This review addresses the molecular and biochemical aspects of the CU pathway in detail, focusing on the type 1 and P pili expressed by uropathogenic Escherichia coli as model systems. We provide an overview of representative CU pili expressed by E. coli and Salmonella, and conclude with a discussion of potential approaches to develop antivirulence therapeutics that interfere with pilus assembly or function.
Collapse
Affiliation(s)
- Glenn T. Werneburg
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, USA
- Center for Infectious Diseases, Stony Brook University, Stony Brook, NY, USA
| | - David G. Thanassi
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, USA
- Center for Infectious Diseases, Stony Brook University, Stony Brook, NY, USA
| |
Collapse
|
18
|
von Mentzer A, Tobias J, Wiklund G, Nordqvist S, Aslett M, Dougan G, Sjöling Å, Svennerholm AM. Identification and characterization of the novel colonization factor CS30 based on whole genome sequencing in enterotoxigenic Escherichia coli (ETEC). Sci Rep 2017; 7:12514. [PMID: 28970563 PMCID: PMC5624918 DOI: 10.1038/s41598-017-12743-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 09/18/2017] [Indexed: 12/20/2022] Open
Abstract
The ability to colonize the small intestine is essential for enterotoxigenic Escherichia coli (ETEC) to cause diarrhea. Although 22 antigenically different colonization factors (CFs) have been identified and characterized in ETEC at least 30% of clinical ETEC isolates lack known CFs. Ninety-four whole genome sequenced "CF negative" isolates were searched for novel CFs using a reverse genetics approach followed by phenotypic analyses. We identified a novel CF, CS30, encoded by a set of seven genes, csmA-G, related to the human CF operon CS18 and the porcine CF operon 987P (F6). CS30 was shown to be thermo-regulated, expressed at 37 °C, but not at 20 °C, by SDS-page and mass spectrometry analyses as well as electron microscopy imaging. Bacteria expressing CS30 were also shown to bind to differentiated human intestinal Caco-2 cells. The genes encoding CS30 were located on a plasmid (E873p3) together with the genes encoding LT and STp. PCR screening of ETEC isolates revealed that 8.6% (n = 13) of "CF negative" (n = 152) and 19.4% (n = 13) of "CF negative" LT + STp (n = 67) expressing isolates analyzed harbored CS30. Hence, we conclude that CS30 is common among "CF negative" LT + STp isolates and is associated with ETEC that cause diarrhea.
Collapse
Affiliation(s)
- Astrid von Mentzer
- Department of Microbiology and Immunology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
| | - Joshua Tobias
- Department of Microbiology and Immunology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Gudrun Wiklund
- Department of Microbiology and Immunology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Stefan Nordqvist
- Department of Microbiology and Immunology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Martin Aslett
- Pathogen Genomics, The Wellcome Trust Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - Gordon Dougan
- Microbial Pathogenesis Group, The Wellcome Trust Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - Åsa Sjöling
- Department of Microbiology, Tumor and Cellbiology, Karolinska Institutet, Stockholm, Sweden
| | - Ann-Mari Svennerholm
- Department of Microbiology and Immunology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| |
Collapse
|
19
|
Sahl JW, Sistrunk JR, Baby NI, Begum Y, Luo Q, Sheikh A, Qadri F, Fleckenstein JM, Rasko DA. Insights into enterotoxigenic Escherichia coli diversity in Bangladesh utilizing genomic epidemiology. Sci Rep 2017; 7:3402. [PMID: 28611468 PMCID: PMC5469772 DOI: 10.1038/s41598-017-03631-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 04/28/2017] [Indexed: 11/08/2022] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) cause more than 500,000 deaths each year in the developing world and are characterized on a molecular level by the presence of genes that encode the heat-stable (ST) and/or heat-labile (LT) enterotoxins, as well as surface structures, known as colonization factors (CFs). Genome sequencing and comparative genomic analyses of 94 previously uncharacterized ETEC isolates demonstrated remarkable genomic diversity, with 28 distinct sequence types identified in three phylogenomic groups. Interestingly, there is a correlation between the genomic sequence type and virulence factor profiles based on prevalence of the isolate, suggesting that there is an optimal combination of genetic factors required for survival, virulence and transmission in the most successful clones. A large-scale BLAST score ratio (LS-BSR) analysis was further applied to identify ETEC-specific genomic regions when compared to non-ETEC genomes, as well as genes that are more associated with clinical presentations or other genotypic markers. Of the strains examined, 21 of 94 ETEC isolates lacked any previously identified CF. Homology searches with the structural subunits of known CFs identified 6 new putative CF variants. These studies provide a roadmap to exploit genomic analyses by directing investigations of pathogenesis, virulence regulation and vaccine development.
Collapse
Affiliation(s)
- Jason W Sahl
- Institute for Genome Sciences, Department of Microbiology and Immunology, University of Maryland School of Medicine, 801 W. Baltimore Street, Suite 600, Baltimore, MD, 21201, USA
- Translational Genomics Research Institute, Flagstaff, AZ, 86001, USA
| | - Jeticia R Sistrunk
- Institute for Genome Sciences, Department of Microbiology and Immunology, University of Maryland School of Medicine, 801 W. Baltimore Street, Suite 600, Baltimore, MD, 21201, USA
| | - Nabilah Ibnat Baby
- Centre for Vaccine Sciences, Immunology Laboratory, International Centre Center for Diarrhoeal Disease Research, Mohakhali, Dhaka, 1212, Bangladesh
| | - Yasmin Begum
- Centre for Vaccine Sciences, Immunology Laboratory, International Centre Center for Diarrhoeal Disease Research, Mohakhali, Dhaka, 1212, Bangladesh
| | - Qingwei Luo
- Department of Medicine, Division of Infectious Diseases, Washington, USA
| | - Alaullah Sheikh
- Centre for Vaccine Sciences, Immunology Laboratory, International Centre Center for Diarrhoeal Disease Research, Mohakhali, Dhaka, 1212, Bangladesh
- The Molecular Microbiology and Microbial Pathogenesis Program, Division of Biology and Biomedical Sciences, Washington University in St. Louis, Washington, USA
| | - Firdausi Qadri
- Centre for Vaccine Sciences, Immunology Laboratory, International Centre Center for Diarrhoeal Disease Research, Mohakhali, Dhaka, 1212, Bangladesh
| | - James M Fleckenstein
- Department of Medicine, Division of Infectious Diseases, Washington, USA
- The Molecular Microbiology and Microbial Pathogenesis Program, Division of Biology and Biomedical Sciences, Washington University in St. Louis, Washington, USA
- Medicine Service, Veterans Affairs Medical Center, St. Louis, MO, USA
| | - David A Rasko
- Institute for Genome Sciences, Department of Microbiology and Immunology, University of Maryland School of Medicine, 801 W. Baltimore Street, Suite 600, Baltimore, MD, 21201, USA.
| |
Collapse
|
20
|
Characterization of enterotoxigenic Escherichia coli strains isolated from the massive multi-pathogen gastroenteritis outbreak in the Antofagasta region following the Chilean earthquake, 2010. INFECTION GENETICS AND EVOLUTION 2017; 52:26-29. [PMID: 28442437 DOI: 10.1016/j.meegid.2017.04.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Revised: 04/20/2017] [Accepted: 04/21/2017] [Indexed: 11/23/2022]
Abstract
In March 2010, a massive outbreak of gastroenteritis started in the region of Antofagasta (northern Chile). The outbreak was mainly attributed to Norovirus genogroup II although ETEC strains were also isolated with high frequency from clinical samples. We review this outbreak and determined that ETEC was an underestimated etiologic agent.
Collapse
|
21
|
Del Canto F, O'Ryan M, Pardo M, Torres A, Gutiérrez D, Cádiz L, Valdés R, Mansilla A, Martínez R, Hernández D, Caro B, Levine MM, Rasko DA, Hill CM, Pop M, Stine OC, Vidal R. Chaperone-Usher Pili Loci of Colonization Factor-Negative Human Enterotoxigenic Escherichia coli. Front Cell Infect Microbiol 2017; 6:200. [PMID: 28111618 PMCID: PMC5216030 DOI: 10.3389/fcimb.2016.00200] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 12/14/2016] [Indexed: 01/05/2023] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) is one of the most common causes of diarrhea worldwide. Among the 25 different ETEC adhesins, 22 are known as "colonization factors" (CFs), of which 17 are assembled by the chaperone-usher (CU) mechanism. Currently, there is no preventive therapy against ETEC, and CFs have been proposed as components for vaccine development. However, studies of diarrhea-causing ETEC strains worldwide indicate that between 15 and 50% of these are negative for known CFs, hindering the selection of the most widespread structures and suggesting that unknown adhesins remain to be identified. Here, we report the result of a comprehensive analysis of 35 draft genomes of ETEC strains which do not carry known adhesin genes; our goal was to find new CU pili loci. The phylogenetic profiles and serogroups of these strains were highly diverse, a majority of which produced only the heat-labile toxin. We identified 10 pili loci belonging to CU families β (1 locus), γ2 (7 loci), κ (1 locus), and π (1 locus), all of which contained the required number of open reading frames (ORFs) to encode functional structures. Three loci were variants of previously-known clusters, three had been only-partially described, and four are novel loci. Intra-loci genetic variability identified would allow the synthesis of up to 14 different structures. Clusters of putative γ2-CU pili were most common (23 strains), followed by putative β-CU pili (12 strains), which have not yet been fully characterized. Overall, our findings significantly increase the number of ETEC adhesion genes associated with human infections.
Collapse
Affiliation(s)
- Felipe Del Canto
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile Santiago, Chile
| | - Miguel O'Ryan
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile Santiago, Chile
| | - Mirka Pardo
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile Santiago, Chile
| | - Alexia Torres
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile Santiago, Chile
| | - Daniela Gutiérrez
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile Santiago, Chile
| | - Leandro Cádiz
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile Santiago, Chile
| | - Raul Valdés
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de ChileSantiago, Chile; Facultad de Química y Biología, Universidad de Santiago de ChileSantiago, Chile
| | - Aquiles Mansilla
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile Santiago, Chile
| | - Rodrigo Martínez
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile Santiago, Chile
| | - Daniela Hernández
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile Santiago, Chile
| | - Benjamin Caro
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile Santiago, Chile
| | - Myron M Levine
- Center for Vaccine Development, University of Maryland School of Medicine Baltimore, MD, USA
| | - David A Rasko
- Department of Microbiology and Immunology, Institute for Genome Sciences, University of Maryland School of Medicine Baltimore, MD, USA
| | - Christopher M Hill
- Center for Bioinformatics and Computational Biology, University of Maryland Institute for Advanced Computer Studies College Park, MD, USA
| | - Mihai Pop
- Center for Bioinformatics and Computational Biology, University of Maryland Institute for Advanced Computer Studies College Park, MD, USA
| | - O Colin Stine
- Department of Epidemiology and Public Health, University of Maryland School of Medicine Baltimore, MD, USA
| | - Roberto Vidal
- Programa de Microbiología y Micología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile Santiago, Chile
| |
Collapse
|
22
|
Mehla K, Ramana J. Identification of epitope-based peptide vaccine candidates against enterotoxigenic Escherichia coli: a comparative genomics and immunoinformatics approach. MOLECULAR BIOSYSTEMS 2016; 12:890-901. [PMID: 26766131 DOI: 10.1039/c5mb00745c] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Enterotoxigenic Escherichia coli (ETEC) associated diarrhea remains a global killer with an estimated annual incidence rate of 840 million infections and 3 800 000 deaths worldwide. There are no vaccines available for ETEC and the traditional vaccine development approach is arduous and time consuming. Thus, alternative in silico approaches for epitope prediction have engrossed the interest of researchers to reduce resources and time of vaccine development. Computational approaches are playing a crucial role in fighting against rapidly growing infectious organisms. In this study we employed an integrated comparative genomics and immunoinformatics approach for proteome scale identification of peptide vaccine candidates. The proteins shared between both ETEC E24377A and H10407 strains, but lacking in commensal E. coli SE11, were subjected to immunoinformatics analysis. For a protein pool shared between different pathogenic ETEC strains, we investigated varied physicochemical and immunogenic properties to prioritize potential vaccine candidates. Epitopes were further tested using docking studies to bind in the MHC-I binding cleft. Predicted epitopes provided more than a 95% population coverage in diarrhea endemic regions presented by major MHC-I supertypes, and bind efficiently to a MHC molecule. We conclude by accentuating that the epitopes predicted in this study are believed to accelerate the development of successful vaccines to control or prevent ETEC infections, albeit the results require experimental validation using model organisms. This study underscores that in silico approaches, together with omics data, hold great potential to be utilized for rapid and reliable genome-wide screening for identification of vaccine candidates against devastating infectious diseases.
Collapse
Affiliation(s)
- Kusum Mehla
- Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Solan, PIN-173234, Himachal Pradesh, India.
| | - Jayashree Ramana
- Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Solan, PIN-173234, Himachal Pradesh, India.
| |
Collapse
|
23
|
Insights into the evolution of pathogenicity of Escherichia coli from genomic analysis of intestinal E. coli of Marmota himalayana in Qinghai-Tibet plateau of China. Emerg Microbes Infect 2016; 5:e122. [PMID: 27924811 PMCID: PMC5180367 DOI: 10.1038/emi.2016.122] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 09/10/2016] [Accepted: 09/19/2016] [Indexed: 01/09/2023]
Abstract
Escherichia coli is both of a widespread harmless gut commensal and a versatile pathogen of humans. Domestic animals are a well-known reservoir for pathogenic E. coli. However, studies of E. coli populations from wild animals that have been separated from human activities had been very limited. Here we obtained 580 isolates from intestinal contents of 116 wild Marmot Marmota himalayana from Qinghai–Tibet plateau, China, with five isolates per animal. We selected 125 (hereinafter referred to as strains) from the 580 isolates for genome sequencing, based on unique pulse field gel electrophoresis patterns and at least one isolate per animal. Whole genome sequence analysis revealed that all 125 strains carried at least one and the majority (79.2%) carried multiple virulence genes based on the analysis of 22 selected virulence genes. In particular, the majority of the strains carried virulence genes from different pathovars as potential 'hybrid pathogens'. The alleles of eight virulence genes from the Marmot E. coli were found to have diverged earlier than all known alleles from human and other animal E. coli. Phylogenetic analysis of the 125 Marmot E. coli genomes and 355 genomes selected from 1622 human and other E. coli strains identified two new phylogroups, G and H, both of which diverged earlier than the other phylogroups. Eight of the 12 well-known pathogenic E. coli lineages were found to share a most recent common ancestor with one or more Marmot E. coli strains. Our results suggested that the intestinal E. coli of the Marmots contained a diverse virulence gene pool and is potentially pathogenic to humans. These findings provided a new understanding of the evolutionary origin of pathogenic E. coli.
Collapse
|
24
|
Gomes TAT, Elias WP, Scaletsky ICA, Guth BEC, Rodrigues JF, Piazza RMF, Ferreira LCS, Martinez MB. Diarrheagenic Escherichia coli. Braz J Microbiol 2016; 47 Suppl 1:3-30. [PMID: 27866935 PMCID: PMC5156508 DOI: 10.1016/j.bjm.2016.10.015] [Citation(s) in RCA: 247] [Impact Index Per Article: 30.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2016] [Accepted: 10/27/2016] [Indexed: 12/22/2022] Open
Abstract
Most Escherichia coli strains live harmlessly in the intestines and rarely cause disease in healthy individuals. Nonetheless, a number of pathogenic strains can cause diarrhea or extraintestinal diseases both in healthy and immunocompromised individuals. Diarrheal illnesses are a severe public health problem and a major cause of morbidity and mortality in infants and young children, especially in developing countries. E. coli strains that cause diarrhea have evolved by acquiring, through horizontal gene transfer, a particular set of characteristics that have successfully persisted in the host. According to the group of virulence determinants acquired, specific combinations were formed determining the currently known E. coli pathotypes, which are collectively known as diarrheagenic E. coli. In this review, we have gathered information on current definitions, serotypes, lineages, virulence mechanisms, epidemiology, and diagnosis of the major diarrheagenic E. coli pathotypes.
Collapse
Affiliation(s)
- Tânia A T Gomes
- Universidade Federal de São Paulo, Escola Paulista de Medicina, Departamento de Microbiologia, Imunologia e Parasitologia, São Paulo, SP, Brazil.
| | - Waldir P Elias
- Instituto Butantan, Laboratório de Bacterologia, São Paulo, SP, Brazil
| | - Isabel C A Scaletsky
- Universidade Federal de São Paulo, Escola Paulista de Medicina, Departamento de Microbiologia, Imunologia e Parasitologia, São Paulo, SP, Brazil
| | - Beatriz E C Guth
- Universidade Federal de São Paulo, Escola Paulista de Medicina, Departamento de Microbiologia, Imunologia e Parasitologia, São Paulo, SP, Brazil
| | - Juliana F Rodrigues
- Universidade de São Paulo, Instituto de Ciências Biomédicas, Departamento de Microbiologia, São Paulo, SP, Brazil
| | - Roxane M F Piazza
- Instituto Butantan, Laboratório de Bacterologia, São Paulo, SP, Brazil
| | - Luís C S Ferreira
- Universidade de São Paulo, Instituto de Ciências Biomédicas, Departamento de Microbiologia, São Paulo, SP, Brazil
| | - Marina B Martinez
- Universidade de São Paulo, Faculdade de Ciências Farmacêuticas, Departamento de Análises Clínicas e Toxicológicas, São Paulo, SP, Brazil
| |
Collapse
|
25
|
Zhang C, Iqbal J, Gómez-Duarte OG. Murine immunization with CS21 pili or LngA major subunit of enterotoxigenic Escherichia coli (ETEC) elicits systemic and mucosal immune responses and inhibits ETEC gut colonization. Vet Microbiol 2016; 202:90-100. [PMID: 26878971 DOI: 10.1016/j.vetmic.2016.02.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 01/24/2016] [Accepted: 02/04/2016] [Indexed: 02/07/2023]
Abstract
CS21 pili of enterotoxigenic Escherichia coli (ETEC) is one of the most prevalent ETEC colonization factors. CS21 major subunit, LngA, mediates ETEC adherence to intestinal cells, and contributes to ETEC pathogenesis in a neonatal mouse infection model. The objectives of this work were to evaluate LngA major subunit purified protein and CS21 purified pili on immunogenicity and protection against ETEC colonization of mice intestine. Recombinant LngA purified protein or purified CS21 pili from E9034A ETEC strain were evaluated for immunogenicity after immunization of C57BL/6 mice. Specific anti-LngA antibodies were detected from mice serum, feces, and intestine fluid samples by ELISA assays. Protection against gut colonization was evaluated on immunized mice orally challenged with wild type E9034A ETEC strain and by subsequent quantification of bacterial colony forming units (CFU) recovered from feces. Recombinant LngA protein and CS21 pili induced specific humoral and mucosal anti-LngA antibodies in the mouse model. CS21 combined with CT delivered intranasally as well as LngA combined with incomplete Freund adjuvant delivered intraperitoneally inhibited ETEC gut colonization in a mouse model. In conclusion, both LngA purified protein and CS21 pili from ETEC are highly immunogenic and may inhibit ETEC intestinal shedding. Our data on immunogenicity and immunoprotection indicates that CS21 is a suitable vaccine candidate for a future multivalent vaccine against ETEC diarrhea.
Collapse
Affiliation(s)
- Chengxian Zhang
- Division of Infectious Diseases, Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Junaid Iqbal
- Division of Infectious Diseases, Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Oscar G Gómez-Duarte
- Division of Infectious Diseases, Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN, USA.
| |
Collapse
|
26
|
Fleckenstein JM, Rasko DA. Overcoming Enterotoxigenic Escherichia coli Pathogen Diversity: Translational Molecular Approaches to Inform Vaccine Design. Methods Mol Biol 2016; 1403:363-83. [PMID: 27076141 DOI: 10.1007/978-1-4939-3387-7_19] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Enterotoxigenic Escherichia coli (ETEC) are a genetically diverse E. coli pathovar that share in the ability to produce heat-labile toxin and/or heat-stable toxins. While these pathogens contribute substantially to the burden of diarrheal illness in developing countries, at present, there is no suitable broadly protective vaccine to prevent these common infections. Most vaccine development attempts to date have followed a classical approach involving a relatively small group of antigens. The extraordinary underlying genetic plasticity of E. coli has confounded the antigen valency requirements based on this approach. The recent discovery of additional virulence proteins within this group of pathogens, as well as the availability of whole-genome sequences from hundreds of ETEC strains to facilitate identification of conserved molecules, now permits a reconsideration of the classical approaches, and the exploration of novel antigenic targets to complement existing strategies overcoming antigenic diversity that has impeded progress toward a broadly protective vaccine. Progress to date in antigen discovery and methods currently available to explore novel immunogens are outlined here.
Collapse
Affiliation(s)
- James M Fleckenstein
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, Campus Box 8051, 660 South Euclid Avenue, St. Louis, MO, USA.
- Molecular Microbiology and Molecular Pathogenesis Program, Division of Biology and Biomedical Sciences, Washington University School of Medicine, St. Louis, MO, USA.
- Medicine Service, Veterans Affairs Medical Center, St. Louis, MO, USA.
| | - David A Rasko
- Department of Microbiology and Immunology, Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
| |
Collapse
|
27
|
TleA, a Tsh-like autotransporter identified in a human enterotoxigenic Escherichia coli strain. Infect Immun 2015; 83:1893-903. [PMID: 25712927 DOI: 10.1128/iai.02976-14] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 02/15/2015] [Indexed: 12/13/2022] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC), a leading cause of acute diarrhea, colonizes the intestine by means of adhesins. However, 15 to 50% of clinical isolates are negative for known adhesins, making it difficult to identify antigens for broad-coverage vaccines. The ETEC strain 1766a, obtained from a child with watery diarrhea in Chile, harbors the colonization factor CS23 but is negative for other known adhesins. One clone, derived from an ETEC 1766a genomic library (clone G10), did not produce CS23 yet was capable of adhering to Caco-2 cells. The goal of this study was to identify the gene responsible for this capacity. Random transposon-based mutagenesis allowed the identification of a 4,110-bp gene that codes for a homologue of the temperature-sensitive hemagglutinin (Tsh) autotransporter described in avian E. coli strains (97% identity, 90% coverage) and that is called TleA (Tsh-like ETEC autotransporter) herein. An isogenic ETEC 1766a strain with a tleA mutation showed an adhesion level similar to that of the wild-type strain, suggesting that the gene does not direct attachment to Caco-2 cells. However, expression of tleA conferred the capacity for adherence to nonadherent E. coli HB101. This effect coincided with the detection of TleA on the surface of nonpermeabilized bacteria, while, conversely, ETEC 1766a seems to secrete most of the produced autotransporter to the medium. On the other hand, TleA was capable of degrading bovine submaxillary mucin and leukocyte surface glycoproteins CD45 and P-selectin glycoprotein ligand 1 (PSGL-1). These results suggest that TleA promotes colonization of the intestinal epithelium and that it may modulate the host immune response.
Collapse
|
28
|
Luo Q, Qadri F, Kansal R, Rasko DA, Sheikh A, Fleckenstein JM. Conservation and immunogenicity of novel antigens in diverse isolates of enterotoxigenic Escherichia coli. PLoS Negl Trop Dis 2015; 9:e0003446. [PMID: 25629897 PMCID: PMC4309559 DOI: 10.1371/journal.pntd.0003446] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 11/26/2014] [Indexed: 12/12/2022] Open
Abstract
Background Enterotoxigenic Escherichia coli (ETEC) are common causes of diarrheal morbidity and mortality in developing countries for which there is currently no vaccine. Heterogeneity in classical ETEC antigens known as colonization factors (CFs) and poor efficacy of toxoid-based approaches to date have impeded development of a broadly protective ETEC vaccine, prompting searches for novel molecular targets. Methodology Using a variety of molecular methods, we examined a large collection of ETEC isolates for production of two secreted plasmid-encoded pathotype-specific antigens, the EtpA extracellular adhesin, and EatA, a mucin-degrading serine protease; and two chromosomally-encoded molecules, the YghJ metalloprotease and the EaeH adhesin, that are not specific to the ETEC pathovar, but which have been implicated in ETEC pathogenesis. ELISA assays were also performed on control and convalescent sera to characterize the immune response to these antigens. Finally, mice were immunized with recombinant EtpA (rEtpA), and a protease deficient version of the secreted EatA passenger domain (rEatApH134R) to examine the feasibility of combining these molecules in a subunit vaccine approach. Principal Findings EtpA and EatA were secreted by more than half of all ETEC, distributed over diverse phylogenetic lineages belonging to multiple CF groups, and exhibited surprisingly little sequence variation. Both chromosomally-encoded molecules were also identified in a wide variety of ETEC strains and YghJ was secreted by 89% of isolates. Antibodies against both the ETEC pathovar-specific and conserved E. coli antigens were present in significantly higher titers in convalescent samples from subjects with ETEC infection than controls suggesting that each of these antigens is produced and recognized during infection. Finally, co-immunization of mice with rEtpA and rEatApH134R offered significant protection against ETEC infection. Conclusions Collectively, these data suggest that novel antigens could significantly complement current approaches and foster improved strategies for development of broadly protective ETEC vaccines. Infectious diarrhea is one of the leading causes of death among young children in developing countries, and a major cause of morbidity in all age groups. The enterotoxigenic Escherichia coli contribute substantially to this burden of diarrheal illness, and have been a focus of vaccine development efforts for more than forty years following their discovery as a cause of severe diarrheal illness. The heat-labile, and/or heat stable enterotoxins that define ETEC are produced by a diverse population of Escherichia coli. This inherent genetic plasticity of E. coli has made it difficult to identify antigens specific to ETEC that are highly conserved. Therefore, identification of protective antigens shared by many ETEC strains will likely play an essential role in development of the next iteration of vaccines.
Collapse
Affiliation(s)
- Qingwei Luo
- Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Firdausi Qadri
- International Centre for Diarrhoeal Disease Research, Bangladesh, Mohakhali, Dhaka, Bangladesh
| | - Rita Kansal
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - David A. Rasko
- Institute for Genome Sciences, Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Alaullah Sheikh
- Molecular Microbiology and Microbial Pathogenesis Program, Division of Biology and Biomedical Sciences, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - James M. Fleckenstein
- Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Molecular Microbiology and Microbial Pathogenesis Program, Division of Biology and Biomedical Sciences, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Medicine Service, Veterans Affairs Medical Center, St. Louis, Missouri, United States of America
- * E-mail:
| |
Collapse
|
29
|
Abstract
Enterotoxigenic Escherichia coli (ETEC) is a major cause of life-threatening diarrheal disease around the world. The major aspects of ETEC virulence are colonization of the small intestine and the secretion of enterotoxins which elicit diarrhea. Intestinal colonization is mediated, in part, by adhesins displayed on the bacterial cell surface. As colonization of the intestine is the critical first step in the establishment of an infection, it represents a potential point of intervention for the prevention of infections. Therefore, colonization factors (CFs) have been important subjects of research in the field of ETEC virulence. Research in this field has revealed that ETEC possesses a large array of serologically distinct CFs that differ in composition, structure, and function. Most ETEC CFs are pili (fimbriae) or related fibrous structures, while other adhesins are simple outer membrane proteins lacking any macromolecular structure. This chapter reviews the genetics, structure, function, and regulation of ETEC CFs and how such studies have contributed to our understanding of ETEC virulence and opened up potential opportunities for the development of preventive and therapeutic interventions.
Collapse
|
30
|
Sjöling Å, von Mentzer A, Svennerholm AM. Implications of enterotoxigenicEscherichia coligenomics for vaccine development. Expert Rev Vaccines 2014; 14:551-60. [DOI: 10.1586/14760584.2015.996553] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
31
|
Contribution of the highly conserved EaeH surface protein to enterotoxigenic Escherichia coli pathogenesis. Infect Immun 2014; 82:3657-66. [PMID: 24935979 DOI: 10.1128/iai.01890-14] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) strains are among the most common causes of diarrheal illness worldwide. These pathogens disproportionately afflict children in developing countries, where they cause substantial morbidity and are responsible for hundreds of thousands of deaths each year. Although these organisms are important targets for enteric vaccines, most development efforts to date have centered on a subset of plasmid-encoded fimbrial adhesins known as colonization factors and heat-labile toxin (LT). Emerging data suggest that ETEC undergoes considerable changes in its surface architecture, sequentially deploying a number of putative adhesins during its interactions with the host. We demonstrate here that one putative highly conserved, chromosomally encoded adhesin, EaeH, engages the surfaces of intestinal epithelial cells and contributes to bacterial adhesion, LT delivery, and colonization of the small intestine.
Collapse
|
32
|
De la Fuente M, Franchi L, Araya D, Díaz-Jiménez D, Olivares M, Álvarez-Lobos M, Golenbock D, González MJ, López-Kostner F, Quera R, Núñez G, Vidal R, Hermoso MA. Escherichia coli isolates from inflammatory bowel diseases patients survive in macrophages and activate NLRP3 inflammasome. Int J Med Microbiol 2014; 304:384-92. [PMID: 24581881 PMCID: PMC4075040 DOI: 10.1016/j.ijmm.2014.01.002] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 12/14/2013] [Accepted: 01/14/2014] [Indexed: 12/16/2022] Open
Abstract
Crohn's disease (CD) is a multifactorial pathology associated with the presence of adherent-invasive Escherichia coli (AIEC) and NLRP3 polymorphic variants. The presence of intracellular E. coli in other intestinal pathologies (OIP) and the role of NLRP3-inflammasome in the immune response activated by these bacteria have not been investigated. In this study, we sought to characterize intracellular strains isolated from patients with CD, ulcerative colitis (UC) and OIP, and analyze NLRP3-inflammasome role in the immune response and bactericidal activity induced in macrophages exposed to invasive bacteria. For this, intracellular E. coli isolation from ileal biopsies, using gentamicin-protection assay, revealed a prevalence and CFU/biopsy of E. coli higher in biopsies from CD, UC and OIP patients than in controls. To characterize bacterial isolates, pulsed-field gel electrophoresis (PFGE) patterns, virulence genes, serogroup and phylogenetic group were analyzed. We found out that bacteria isolated from a given patient were closely related and shared virulence factors; however, strains from different patients were genetically heterogeneous. AIEC characteristics in isolated strains, such as invasive and replicative properties, were assessed in epithelial cells and macrophages, respectively. Some strains from CD and UC demonstrated AIEC properties, but not strains from OIP. Furthermore, the role of NLRP3 in pro-inflammatory cytokines production and bacterial elimination was determined in macrophages. E. coli strains induced IL-1β through NLRP3-dependent mechanism; however, their elimination by macrophages was independent of NLRP3. Invasiveness of intracellular E. coli strains into the intestinal mucosa and IL-1β production may contribute to CD and UC pathogenesis.
Collapse
Affiliation(s)
- Marjorie De la Fuente
- Disciplinary Program of Immunology, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, CL 8380453, Chile
| | - Luigi Franchi
- Department of Pathology and Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Daniela Araya
- Disciplinary Program of Microbiology, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, CL 8380453, Chile
| | - David Díaz-Jiménez
- Disciplinary Program of Immunology, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, CL 8380453, Chile
| | - Mauricio Olivares
- Disciplinary Program of Immunology, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, CL 8380453, Chile
| | - Manuel Álvarez-Lobos
- Gastroenterology Department, Hospital Clínico Pontificia Universidad Católica de Chile, Santiago, CL 6513677, Chile
| | - Douglas Golenbock
- Division of Infectious Diseases & Immunology, University of Massachusetts Medical School, Worcester, MA, USA
| | - María-Julieta González
- Cell and Molecular Biology Program, Biomedical Sciences Institute, Faculty of Medicine, Universidad de Chile, Santiago, CL 8380453, Chile
| | - Francisco López-Kostner
- Laboratory of Oncology and Molecular Genetics, Colorectal Surgery Unit, Clínica Las Condes, Santiago, CL 7591018, Chile
| | - Rodrigo Quera
- Gastroenterology Unit, Clínica Las Condes, Santiago, CL 7591018, Chile
| | - Gabriel Núñez
- Department of Pathology and Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Roberto Vidal
- Disciplinary Program of Microbiology, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, CL 8380453, Chile
| | - Marcela A Hermoso
- Disciplinary Program of Immunology, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, CL 8380453, Chile.
| |
Collapse
|
33
|
Pathogenesis of human enterovirulent bacteria: lessons from cultured, fully differentiated human colon cancer cell lines. Microbiol Mol Biol Rev 2014; 77:380-439. [PMID: 24006470 DOI: 10.1128/mmbr.00064-12] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Hosts are protected from attack by potentially harmful enteric microorganisms, viruses, and parasites by the polarized fully differentiated epithelial cells that make up the epithelium, providing a physical and functional barrier. Enterovirulent bacteria interact with the epithelial polarized cells lining the intestinal barrier, and some invade the cells. A better understanding of the cross talk between enterovirulent bacteria and the polarized intestinal cells has resulted in the identification of essential enterovirulent bacterial structures and virulence gene products playing pivotal roles in pathogenesis. Cultured animal cell lines and cultured human nonintestinal, undifferentiated epithelial cells have been extensively used for understanding the mechanisms by which some human enterovirulent bacteria induce intestinal disorders. Human colon carcinoma cell lines which are able to express in culture the functional and structural characteristics of mature enterocytes and goblet cells have been established, mimicking structurally and functionally an intestinal epithelial barrier. Moreover, Caco-2-derived M-like cells have been established, mimicking the bacterial capture property of M cells of Peyer's patches. This review intends to analyze the cellular and molecular mechanisms of pathogenesis of human enterovirulent bacteria observed in infected cultured human colon carcinoma enterocyte-like HT-29 subpopulations, enterocyte-like Caco-2 and clone cells, the colonic T84 cell line, HT-29 mucus-secreting cell subpopulations, and Caco-2-derived M-like cells, including cell association, cell entry, intracellular lifestyle, structural lesions at the brush border, functional lesions in enterocytes and goblet cells, functional and structural lesions at the junctional domain, and host cellular defense responses.
Collapse
|
34
|
Vilchez S, Becker-Dreps S, Amaya E, Perez C, Paniagua M, Reyes D, Espinoza F, Weintraub A. Characterization of enterotoxigenic Escherichia coli strains isolated from Nicaraguan children in hospital, primary care and community settings. J Med Microbiol 2014; 63:729-734. [PMID: 24554743 DOI: 10.1099/jmm.0.066779-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) is one of the most common causes of diarrhoea among young children in developing countries. ETEC vaccines offer promise in reducing the burden of ETEC disease, but the development of these vaccines relies on the characterization of ETEC isolates from a variety of settings. To best reflect the full spectrum of ETEC disease in León, Nicaragua, the aim of this study was to characterize ETEC strains isolated from children with diarrhoea attending different settings (hospital, primary care clinics and in the community) and children from different age groups. We characterized ETEC isolates in terms of their colonization factors (CFs) and enterotoxins, and determined whether these factors varied with setting and age group. Diarrhoeal stool samples were obtained from children under the age of 60 months from: (1) the regional public hospital, (2) four public primary care clinics, and (3) a population-based cohort. In total, 58 ETEC-positive isolates were analysed by multiplex-PCR assays for the identification of CFs (CS1, CS2, CS3, CS4, CS5, CS6, CS7, CS8, CS12, CS13, CS14, CS15, CS17, CS18, CS19, CS20, CS21, CS22 and CFA/I), and enterotoxins [heat-labile toxin (LT) and heat-stable variants STh and STp]. The frequency of CFs and enterotoxins was compared among the three settings and for different age groups, using Fisher's exact test or a χ(2) test. At least one CF was detected among one-half of samples; CS19 was detected among all strains in which a CF was identified, either alone or in combination with another CF. Among all CFs detected, 91.7 % were identified as members of the class 5 fimbrial family. CFs were detected more commonly among samples from infants captured in the health facility setting compared with the community setting. Overall, LT was detected among 67.2 % of samples, STh was detected among 20.7 % and both enterotoxins were detected among 12.1 %. The enterotoxin STh was detected more commonly among cases in the community, whilst a combination of STh and LT was detected more commonly among cases treated in health facilities. Our results suggest that, to protect against diarrhoeal cases associated with this E. coli pathotype in León, Nicaragua, an ETEC vaccine that effectively targets the archeotype CFA/I of the class 5 fimbrial family would be the most effective in this setting.
Collapse
Affiliation(s)
- Samuel Vilchez
- Department of Microbiology, Faculty of Medical Sciences, National Autonomous University of Nicaragua (UNAN), León, Nicaragua
| | - Sylvia Becker-Dreps
- Department of Family Medicine, University of North Carolina at Chapel Hill, 590 Manning Drive, Chapel Hill, NC, USA
| | - Erick Amaya
- Department of Microbiology, Faculty of Medical Sciences, National Autonomous University of Nicaragua (UNAN), León, Nicaragua
| | - Claudia Perez
- Department of Microbiology, Faculty of Medical Sciences, National Autonomous University of Nicaragua (UNAN), León, Nicaragua
| | - Margarita Paniagua
- Department of Microbiology, Faculty of Medical Sciences, National Autonomous University of Nicaragua (UNAN), León, Nicaragua
| | - Daniel Reyes
- Department of Microbiology, Faculty of Medical Sciences, National Autonomous University of Nicaragua (UNAN), León, Nicaragua
| | - Felix Espinoza
- Department of Microbiology, Faculty of Medical Sciences, National Autonomous University of Nicaragua (UNAN), León, Nicaragua
| | - Andrej Weintraub
- Division of Clinical Microbiology, Department of Laboratory Medicine, Karolinska Institutet, Karolinska University Hospital, Huddinge, S-141 86, Stockholm, Sweden
| |
Collapse
|
35
|
Croxen MA, Law RJ, Scholz R, Keeney KM, Wlodarska M, Finlay BB. Recent advances in understanding enteric pathogenic Escherichia coli. Clin Microbiol Rev 2013; 26:822-80. [PMID: 24092857 PMCID: PMC3811233 DOI: 10.1128/cmr.00022-13] [Citation(s) in RCA: 829] [Impact Index Per Article: 75.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Although Escherichia coli can be an innocuous resident of the gastrointestinal tract, it also has the pathogenic capacity to cause significant diarrheal and extraintestinal diseases. Pathogenic variants of E. coli (pathovars or pathotypes) cause much morbidity and mortality worldwide. Consequently, pathogenic E. coli is widely studied in humans, animals, food, and the environment. While there are many common features that these pathotypes employ to colonize the intestinal mucosa and cause disease, the course, onset, and complications vary significantly. Outbreaks are common in developed and developing countries, and they sometimes have fatal consequences. Many of these pathotypes are a major public health concern as they have low infectious doses and are transmitted through ubiquitous mediums, including food and water. The seriousness of pathogenic E. coli is exemplified by dedicated national and international surveillance programs that monitor and track outbreaks; unfortunately, this surveillance is often lacking in developing countries. While not all pathotypes carry the same public health profile, they all carry an enormous potential to cause disease and continue to present challenges to human health. This comprehensive review highlights recent advances in our understanding of the intestinal pathotypes of E. coli.
Collapse
|
36
|
Abstract
The enterotoxigenic Escherichia coli are a pervasive cause of serious diarrheal illness in developing countries. Presently, there is no vaccine to prevent these infections, and many features of the basic pathogenesis of these organisms remain poorly understood. Until very recently most pathogenesis studies had focused almost exclusively on a small subset of known "classical" virulence genes, namely fimbrial colonization factors and the heat-labile (LT) and heat stable (ST) enterotoxins. However, recent investigations of pathogen-host interactions reveal a surprisingly complex and intricately orchestrated engagement involving the interplay of classical and "novel" virulence genes, as well as participation of genes highly conserved in the E. coli species. These studies may inform further rational approaches to vaccine development for these important pathogens.
Collapse
Affiliation(s)
- James M Fleckenstein
- Department of Medicine; Washington University School of Medicine; St. Louis, MO USA,Medicine Service; Veterans Affairs Medical Center; St. Louis, MO USA,Correspondence to: James M Fleckenstein,
| | - George M Munson
- Department of Microbiology and Immunology; University of Miami; Miller School of Medicine; Miami, FL USA
| | - David A Rasko
- Department of Microbiology and Immunology; University of Maryland School of Medicine; Baltimore, MD USA,Institute for Genome Sciences; University of Maryland School of Medicine; Baltimore, MD USA
| |
Collapse
|