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Pasqua M, Michelacci V, Di Martino ML, Tozzoli R, Grossi M, Colonna B, Morabito S, Prosseda G. The Intriguing Evolutionary Journey of Enteroinvasive E. coli (EIEC) toward Pathogenicity. Front Microbiol 2017; 8:2390. [PMID: 29259590 PMCID: PMC5723341 DOI: 10.3389/fmicb.2017.02390] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 11/20/2017] [Indexed: 01/01/2023] Open
Abstract
Among the intestinal pathogenic Escherichia coli, enteroinvasive E. coli (EIEC) are a group of intracellular pathogens able to enter epithelial cells of colon, multiplicate within them, and move between adjacent cells with a mechanism similar to Shigella, the ethiological agent of bacillary dysentery. Despite EIEC belong to the same pathotype of Shigella, they neither have the full set of traits that define Shigella nor have undergone the extensive gene decay observed in Shigella. Molecular analysis confirms that EIEC are widely distributed among E. coli phylogenetic groups and correspond to bioserotypes found in many E. coli serogroups. Like Shigella, also in EIEC the critical event toward a pathogenic life-style consisted in the acquisition by horizontal gene transfer of a large F-type plasmid (pINV) containing the genes required for invasion, intracellular survival, and spreading through the intestinal mucosa. In Shigella, the ample gain in virulence determinants has been counteracted by a substantial loss of functions that, although important for the survival in the environment, are redundant or deleterious for the life inside the host. The pathoadaptation process that has led Shigella to modify its metabolic profile and increase its pathogenic potential is still in infancy in EIEC, although maintenance of some features typical of E. coli might favor their emerging relevance as intestinal pathogens worldwide, as documented by recent outbreaks in industrialized countries. In this review, we will discuss the evolution of EIEC toward Shigella-like invasive forms going through the epidemiology, including the emergence of new virulent strains, their genome organization, and the complex interactions they establish with the host.
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Affiliation(s)
- Martina Pasqua
- Istituto Pasteur Italia, Department of Biology and Biotechnology "C. Darwin", Sapienza Università di Roma, Rome, Italy
| | - Valeria Michelacci
- European Union Reference Laboratory for Escherichia coli, Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Rome, Italy
| | - Maria Letizia Di Martino
- Istituto Pasteur Italia, Department of Biology and Biotechnology "C. Darwin", Sapienza Università di Roma, Rome, Italy
| | - Rosangela Tozzoli
- European Union Reference Laboratory for Escherichia coli, Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Rome, Italy
| | - Milena Grossi
- Istituto Pasteur Italia, Department of Biology and Biotechnology "C. Darwin", Sapienza Università di Roma, Rome, Italy
| | - Bianca Colonna
- Istituto Pasteur Italia, Department of Biology and Biotechnology "C. Darwin", Sapienza Università di Roma, Rome, Italy
| | - Stefano Morabito
- European Union Reference Laboratory for Escherichia coli, Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Rome, Italy
| | - Gianni Prosseda
- Istituto Pasteur Italia, Department of Biology and Biotechnology "C. Darwin", Sapienza Università di Roma, Rome, Italy
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da Silva LC, de Mello Santos AC, Silva RM. Uropathogenic Escherichia coli pathogenicity islands and other ExPEC virulence genes may contribute to the genome variability of enteroinvasive E. coli. BMC Microbiol 2017; 17:68. [PMID: 28302076 PMCID: PMC5356261 DOI: 10.1186/s12866-017-0979-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 03/11/2017] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Enteroinvasive Escherichia coli (EIEC) may be the causative agent of part of those million cases of diarrhea illness reported worldwide every year and attributable to Shigella. That is because both enteropathogens have many common characteristics that difficult their identification either by traditional microbiological methods or by molecular tools used in the clinical laboratory settings. While Shigella has been extensively studied, EIEC remains barely characterized at the molecular level. Recent EIEC important outbreaks, apparently generating more life-threatening cases, have prompted us to screen EIEC for virulence traits usually related to extraintestinal pathogenic E. coli (ExPEC). That could explain the appearance of EIEC strains presenting higher virulence potential. RESULTS EIEC strains were distributed mainly in three phylogroups in a serogroup-dependent manner. Serogroups O124, O136, O144, and O152 were exclusively classified in phylogroup A; O143 in group E; and O28ac and O29 in group B1. Only two serogroups showed diverse phylogenetic origin as follows: O164 was assigned to groups A, B1, C, and B2 (one strain each), and O167 in groups E (five strains), and A (one strain) (Table 1). Eleven of 20 virulence genes (VGs) searched were detected, and the majority of the 19 different VGs combinations found were serogroup-specific. Uropathogenic E. coli (UPEC) PAI genetic markers were detected in all EIEC strains. PAIs IJ96 and IICFT073 were the most frequent (92.1 and 80.4%, respectively). PAI IV536 was restricted to some serogroups from phylogroups A, B1 and E. PAI ICFT073 was uniquely detected in phylogroups B2 and E. A total of 45 (88%) strains presented multiple PAI markers (two to four). PAIs IJ96 and IICFT073 were found together in 80% of strains. CONCLUSIONS EIEC is a DEC pathovar that presents VGs and pathogenicity island genetic markers typically associated with ExPEC, especially UPEC. These features are distributed in a phylogenetic and serogroup-dependent manner suggesting the existence of stable EIEC subclones. The presence of phylogroups B2 and E strains allied to the presence of UPEC virulence-associated genes may underscore the ongoing evolution of EIEC towards a hypervirulent pathotype.
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Affiliation(s)
- Laís Cristina da Silva
- Department of Microbiology, Immunology, and Parasitology, Federal University of São Paulo, Rua Botucatu 862, CEP 04023-062, São Paulo, SP, Brazil
| | - Ana Carolina de Mello Santos
- Department of Microbiology, Immunology, and Parasitology, Federal University of São Paulo, Rua Botucatu 862, CEP 04023-062, São Paulo, SP, Brazil
| | - Rosa Maria Silva
- Department of Microbiology, Immunology, and Parasitology, Federal University of São Paulo, Rua Botucatu 862, CEP 04023-062, São Paulo, SP, Brazil.
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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: 252] [Impact Index Per Article: 31.5] [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.
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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
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Kosek M, Yori PP, Gilman RH, Vela H, Olortegui MP, Chavez CB, Calderon M, Bao JP, Hall E, Maves R, Burga R, Sanchez GM. Facilitated molecular typing of Shigella isolates using ERIC-PCR. Am J Trop Med Hyg 2012; 86:1018-25. [PMID: 22665611 DOI: 10.4269/ajtmh.2012.11-0671] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
To evaluate the performance of enterobacterial repetitive intergenic sequence-based polymerase chain reaction (ERIC-PCR) typing versus the current standard for the typing of Shigella pulsed gel electrophoresis (PFGE), we typed 116 Shigella isolates from a village in an endemic setting over a 20-month period using both methods. PFGE identified 37 pulse types and had a discrimination index of 0.925 (95% confidence interval = 0.830-1.00), whereas ERIC-PCR identified 42 types and had a discrimination index of 0.961 (95% confidence interval = 0.886-1.00). PFGE and ERIC-PCR showed a 90.4% correlation in the designation of isolates as clonal or non-clonal in pairwise comparisons. Both systems were highly reproducible and provided highly similar and supplementary data compared with serotyping regarding the transmission dynamics of shigellosis in this community. ERIC-PCR is considerably more rapid and inexpensive than PFGE and may have a complementary role to PFGE for initial investigations of hypothesized outbreaks in resource-limited settings.
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Affiliation(s)
- Margaret Kosek
- Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA.
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Hayford AE, Mammel MK, Lacher DW, Brown EW. Single nucleotide polymorphism (SNP)-based differentiation of Shigella isolates by pyrosequencing. INFECTION GENETICS AND EVOLUTION 2011; 11:1761-8. [PMID: 21839856 DOI: 10.1016/j.meegid.2011.07.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2011] [Revised: 07/15/2011] [Accepted: 07/19/2011] [Indexed: 11/17/2022]
Affiliation(s)
- Alice E Hayford
- Division of Molecular Biology, Center for Food Safety and Applied Nutrition, US Food and Drug Administration, Laurel, MD 20708, USA.
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Atypical enteropathogenic Escherichia coli that contains functional locus of enterocyte effacement genes can be attaching-and-effacing negative in cultured epithelial cells. Infect Immun 2011; 79:1833-41. [PMID: 21343354 DOI: 10.1128/iai.00693-10] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Enteropathogenic Escherichia coli (EPEC) induces a characteristic histopathology on enterocytes known as the attaching-and-effacing (A/E) lesion, which is triggered by proteins encoded by the locus of enterocyte effacement (LEE). EPEC is currently classified as typical EPEC (tEPEC) and atypical EPEC (aEPEC), based on the presence or absence of the EPEC adherence factor plasmid, respectively. Here we analyzed the LEE regions of three aEPEC strains displaying the localized adherence-like (LAL), aggregative adherence (AA), and diffuse adherence (DA) patterns on HEp-2 cells as well as one nonadherent (NA) strain. The adherence characteristics and the ability to induce A/E lesions were investigated with HeLa, Caco-2, T84, and HT29 cells. The adherence patterns and fluorescent actin staining (FAS) assay results were reproducible with all cell lines. The LEE region was structurally intact and functional in all strains regardless of their inability to cause A/E lesions. An EspF(U)-expressing plasmid (pKC471) was introduced into all strains, demonstrating no influence of this protein on either the adherence patterns or the capacity to cause A/E of the adherent strains. However, the NA strain harboring pKC471 expressed the LAL pattern and was able to induce A/E lesions on HeLa cells. Our data indicate that FAS-negative aEPEC strains are potentially able to induce A/E in vivo, emphasizing the concern about this test for the determination of aEPEC virulence. Also, the presence of EspF(U) was sufficient to provide an adherent phenotype for a nonadherent aEPEC strain via the direct or indirect activation of the LEE4 and LEE5 operons.
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Sharma A, Singh SK, Bajpai D. Phenotypic and genotypic characterization of Shigella spp. with reference to its virulence genes and antibiogram analysis from river Narmada. Indian J Microbiol 2009; 49:259-65. [PMID: 23100779 DOI: 10.1007/s12088-009-0046-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2008] [Accepted: 08/31/2008] [Indexed: 11/25/2022] Open
Abstract
Water samples of the river Narmada from the source to the mouth were analyzed for the presence of shigellae and the Shigella isolates from 180 water samples were characterized by biotyping, serotyping and molecular typing. Out of all the 40 isolates, 23 were identified as S. flexneri, 10 as S. sonnei and 7 as S. dysenteriae. Serotyping was found to be the better identification method than biotyping. In the present investigation, amplified ribosomal DNA restriction analysis (ARDRA) with a probe complementary to 16S rRNA was performed. Repeated ARDRA analysis established the similarities between the isolates and thus suggested ARDRA as authentic and precise detection protocol. The isolates were also analyzed for the presence of virulence genes including ipaBCD, ipaH and stx1. All the 40 isolates of Shigella were found to be positive for the ipaH gene. The plasmid encoded invasion-associated genes ipaBCD were present only in S. flexneri and the stx1 gene was found only in S. dysenteriae. This study demonstrated the existence of Shigella in the river Narmada and the dispersion of different virulence genes among the isolates, which appear to constitute an environmental reservoir of Shigella-specific virulence genes.
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Affiliation(s)
- Anjana Sharma
- Bacteriology Laboratory, Department of P.G. Studies and Research in Biological Science, R.D. University, Jabalpur, 482001 MP India
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9
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Phenotypic and genotypic characterization of Shigella spp. with reference to its virulence genes and antibiogram analysis from river Narmada. Microbiol Res 2009; 165:33-42. [PMID: 19501495 DOI: 10.1016/j.micres.2008.02.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2006] [Revised: 08/07/2007] [Accepted: 02/12/2008] [Indexed: 11/23/2022]
Abstract
Water samples of the river Narmada from origin to end were analyzed for the presence of shigellae. Analysis of 40 water samples by biotyping, serotyping, and molecular typing were done. Out of all 40 isolates, 23 were identified as Shigella flexneri, 10 as Shigella sonnei, and seven as Shigella dysenteriae. Serotyping was found to be a better identification method than biotyping since biotyping was not found to be very sharp. In the present investigation, amplified ribosomal DNA restriction analysis (ARDRA) with a probe complementary to 16S rRNA was performed. Repeated ARDRA analysis establishes the similarities between the isolates and thus suggested ARDRA as authentic and precise detection protocol. The isolates were also analyzed for the presence of virulence genes including ipaBCD, ipaH, and stx1 and all the 40 isolates of Shigella showed positive result for ipaH gene while the plasmid encoded invasion-associated genes ipaBCD was present only in S. flexneri and stx1 gene was present only in S. dysenteriae. This study demonstrated the existence of Shigella in the river Narmada and dispersion of different virulence genes among these isolates, which appear to constitute an environmental reservoir of Shigella-specific virulence genes.
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10
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Reinhardt EL, Ramos PL, Manfio GP, Barbosa HR, Pavan C, Moreira-Filho CA. Molecular characterization of nitrogen-fixing bacteria isolated from brazilian agricultural plants at São Paulo state. Braz J Microbiol 2008; 39:414-22. [PMID: 24031239 PMCID: PMC3768443 DOI: 10.1590/s1517-83822008000300002] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2007] [Revised: 10/21/2007] [Accepted: 07/24/2008] [Indexed: 11/22/2022] Open
Abstract
Fourteen strains of nitrogen-fixing bacteria were isolated from different agricultural plant species, including cassava, maize and sugarcane, using nitrogen-deprived selective isolation conditions. Ability to fix nitrogen was verified by the acetylene reduction assay. All potentially nitrogen-fixing strains tested showed positive hybridization signals with a nifH probe derived from Azospirillum brasilense. The strains were characterized by RAPD, ARDRA and 16S rDNA sequence analysis. RAPD analyses revealed 8 unique genotypes, the remaining 6 strains clustered into 3 RAPD groups, suggesting a clonal origin. ARDRA and 16S rDNA sequence analyses allowed the assignment of 13 strains to known groups of nitrogen-fixing bacteria, including organisms from the genera Azospirillum, Herbaspirillum, Pseudomonas and Enterobacteriaceae. Two strains were classified as Stenotrophomonas ssp. Molecular identification results from 16S rDNA analyses were also corroborated by morphological and biochemical data.
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11
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Bando SY, Trabulsi LR, Moreira-Filho CA. Genetic relationship of diarrheagenic Escherichia coli pathotypes among the enteropathogenic Escherichia coli O serogroup. Mem Inst Oswaldo Cruz 2007; 102:169-74. [PMID: 17426881 DOI: 10.1590/s0074-02762007005000018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2006] [Indexed: 11/21/2022] Open
Abstract
The genetic relationship among the Escherichia coli pathotypes was investigated. We used random amplified polymorphic DNA (RAPD) data for constructing a dendrogram of 73 strains of diarrheagenic E. coli. A phylogenetic tree encompassing 15 serotypes from different pathotypes was constructed using multilocus sequence typing data. Phylogram clusters were used for validating RAPD data on the clonality of enteropathogenic E. coli (EPEC) O serogroup strains. Both analyses showed very similar topologies, characterized by the presence of two major groups: group A includes EPEC H6 and H34 strains and group B contains the other EPEC strains plus all serotypes belonging to atypical EPEC, enteroaggregative E. coli (EAEC) and enterohemorrhagic E. coli (EHEC). These results confirm the existence of two evolutionary divergent groups in EPEC: one is genetically and serologically very homogeneous whereas the other harbors EPEC and non-EPEC serotypes. The same situation was found for EAEC and EHEC.
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Affiliation(s)
- Silvia Y Bando
- Departamento de Imunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, Brasil
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12
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Adachi JA, Barriga J, Ericsson CD. Bacterial gut infections. Curr Opin Infect Dis 2006; 12:459-66. [PMID: 17035812 DOI: 10.1097/00001432-199910000-00008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Infections of the bowel as a result of bacterial enteropathogens are one of the most common medical problems. The use of novel molecular biology techniques and the recent development of new antimicrobial drugs and vaccines are helping us to identify, understand, treat and prevent these infections.
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Affiliation(s)
- J A Adachi
- Department of Internal Medicine, Division of Infectious Diseases, University of Texas-Houston Medical School, Houston, TX 77030, USA
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Sung MJ, Chang CH, Yoon YK, Park SE. Clinical aspects of an outbreak of Serratia marcescens infections in neonates. KOREAN JOURNAL OF PEDIATRICS 2006. [DOI: 10.3345/kjp.2006.49.5.500] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Min-Jung Sung
- Department of Pediatrics, College of Medicine, Pusan National University, Busan, Korea
| | - Chul-Hun Chang
- Department of Laboratory Medicine, College of Medicine, Pusan National University, Busan, Korea
| | - Yeon-Kyong Yoon
- Infection Control Team, College of Medicine, Pusan National University, Busan, Korea
| | - Su-Eun Park
- Department of Pediatrics, College of Medicine, Pusan National University, Busan, Korea
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Moon JY, Park JH, Kim YB. Molecular epidemiological characteristics of virulence factors on enteroaggregative E. coli. FEMS Microbiol Lett 2005; 253:215-20. [PMID: 16257141 DOI: 10.1016/j.femsle.2005.09.038] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2005] [Revised: 09/22/2005] [Accepted: 09/25/2005] [Indexed: 10/25/2022] Open
Abstract
Escherichia coli with various types of adherence patterns to cultured epithelial cells have been described over the years as being associated with both acute and persistent diarrhea. Most enteroaggregative E. coli (EAEC) strains harbor a 60- to 65-MDa plasmid called pAA which has been shown to encode the aggregative adherence fimbriae AAF/I and AAF/II; the enterotoxin EAST1 and Pet, a serine protease which has been described as causing enterotoxic and cytotoxic effects. Another serine protease denominated Pic, encoded by a chromosomal gene displaying mucinolytic activity, serum resistance, and hemagglutination, has also been associated with EAEC strains. In this study, EAEC strains that isolated from the rectal swab of neonates at the neonatal intensive care unit of Pusan National University Hospital in 2003 were tested for the presence of the pAA using polymerase chain reaction (PCR) and DNA colony hybridization methods. To further characterize these EAEC strains, we used PCR to detect genes for proposed EAEC virulence factors and examined HeLa cell adherence assay, antimicrobial susceptibility test, serotyping, cytotoxicity test and epidemiological characteristics. EAEC isolates found were genotyped by random amplified polymorphic DNA and pulsed-field gel electrophoresis.
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Affiliation(s)
- Ji Young Moon
- Department of Microbiology and Immunology, College of Medicine, Pusan National University, Busan 602-739, South Korea
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Lan R, Alles MC, Donohoe K, Martinez MB, Reeves PR. Molecular evolutionary relationships of enteroinvasive Escherichia coli and Shigella spp. Infect Immun 2004; 72:5080-8. [PMID: 15322001 PMCID: PMC517479 DOI: 10.1128/iai.72.9.5080-5088.2004] [Citation(s) in RCA: 123] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Enteroinvasive Escherichia coli (EIEC), a distinctive pathogenic form of E. coli causing dysentery, is similar in many properties to bacteria placed in the four species of Shigella. Shigella has been separated as a genus but in fact comprises several clones of E. coli. The evolutionary relationships of 32 EIEC strains of 12 serotypes have been determined by sequencing of four housekeeping genes and two plasmid genes which were used previously to determine the relationships of Shigella strains. The EIEC strains were grouped in four clusters with one outlier strain, indicating independent derivation of EIEC several times. Three of the four clusters contain more than one O antigen type. One EIEC strain (an O112ac:H- strain) was found in Shigella cluster 3 but is not identical to the Shigella cluster 3 D2 and B15 strains with the same O antigen. Two forms of the virulence plasmid pINV have been identified in Shigella strains by using the sequences of ipgD and mxiA genes, and all but two of our EIEC strains have pINV A. The EIEC strains were grouped in two subclusters with a very low level of variation, generally not intermingled with Shigella pINV A strains. The EIEC clusters based on housekeeping genes were reflected in the plasmid gene sequences, with some exceptions. Two strains were found in the pINV B form by using the ipgD sequence, with one strain having an mxiA sequence similar to the divergent sequence of D1. Clearly, EIEC and Shigella spp. form a pathovar of E. coli.
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Affiliation(s)
- Ruiting Lan
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Australia.
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16
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Escobar-Páramo P, Clermont O, Blanc-Potard AB, Bui H, Le Bouguénec C, Denamur E. A specific genetic background is required for acquisition and expression of virulence factors in Escherichia coli. Mol Biol Evol 2004; 21:1085-94. [PMID: 15014151 DOI: 10.1093/molbev/msh118] [Citation(s) in RCA: 238] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In bacteria, the evolution of pathogenicity seems to be the result of the constant arrival of virulence factors (VFs) into the bacterial genome. However, the integration, retention, and/or expression of these factors may be the result of the interaction between the new arriving genes and the bacterial genomic background. To test this hypothesis, a phylogenetic analysis was done on a collection of 98 Escherichia coli/Shigella strains representing the pathogenic and commensal diversity of the species. The distribution of 17 VFs associated to the different E. coli pathovars was superimposed on the phylogenetic tree. Three major types of VFs can be recognized: (1) VFs that arrive and are expressed in different genetic backgrounds (such as VFs associated with the pathovars of mild chronic diarrhea: enteroaggregative, enteropathogenic, and diffusely-adhering E. coli), (2) VFs that arrive in different genetic backgrounds but are preferentially found, associated with a specific pathology, in only one particular background (such as VFs associated with extraintestinal diseases), and (3) VFs that require a particular genetic background for the arrival and expression of their virulence potential (such as VFs associated with pathovars typical of severe acute diarrhea: enterohemorragic, enterotoxigenic, and enteroinvasive E. coli strains). The possibility of a single arrival of VFs by chance, followed by a vertical transmission, was ruled out by comparing the evolutionary histories of some of these VFs to the strain phylogeny. These evidences suggest that important changes in the genome of E. coli have occurred during the diversification of the species, allowing the virulence factors associated with severe acute diarrhea to arrive in the population. Thus, the E. coli genome seems to be formed by an "ancestral" and a "derived" background, each one responsible for the acquisition and expression of different virulence factors.
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Luo W, Wang S, Peng X. Identification of shiga toxin-producing bacteria by a new immuno-capture toxin gene PCR. FEMS Microbiol Lett 2002; 216:39-42. [PMID: 12423749 DOI: 10.1111/j.1574-6968.2002.tb11411.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Infections with bacteria producing shiga toxin are responsible for widespread disease and for the death of a large number of people. In the present study, we have developed a rapid method of high specificity for the detection of Shigella dysenteriae by combining immuno-capture of the bacteria and polymerase chain reaction (PCR) amplification of their toxin gene. We compared the sensitivity of our new method, referred to as immuno-capture toxin gene PCR (iTGPCR), with a conventional TGPCR (cTGPCR) method in detecting S. dysenteriae. Approximately 100 colony forming units (CFU) of bacteria in a volume of 400 microl were divided into 20 tubes with 5 CFU (20 microl). One group of 10 tubes was analyzed by iTGPCR and the other by cTGPCR amplification. All were positive in the 10 tubes using iTGPCR but, in contrast, only half were positive in the 10 tubes with the cTGPCR method. This method was used to detect S. dysenteriae type I in sewage samples without the normal tedious preparation methods. These findings suggest that iTGPCR gives enhanced test sensitivity, and allows determination of pathogen serotype, and differentiation of toxin-producing strains from non toxin-producing strains.
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Affiliation(s)
- Wen Luo
- The Key Laboratory of Education Ministry for Cell Biology and Tumor Cell Engineering, Department of Biology, School of Life Sciences, Xiamen University, PR China
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18
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Nucci C, da Silveira WD, da Silva Corrêa S, Nakazato G, Bando SY, Ribeiro MA, Pestana de Castro AF. Microbiological comparative study of isolates of Edwardsiella tarda isolated in different countries from fish and humans. Vet Microbiol 2002; 89:29-39. [PMID: 12223160 DOI: 10.1016/s0378-1135(02)00151-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
It is difficult to use tissue culture assays to investigate adherence and other properties of Edwardsiella tarda because the organism is invasive and produces a potent hemolysin. We therefore relied on polymerase chain reaction (PCR) to determine the occurrence of genes for enterotoxins (LT-I, EAST-1), Shiga toxin (Stx-1, Stx-2), cytotoxic necrotizing factors (CNF-1, CNF-2), aerobactin, invasion plasmid of enteroinvasive Escherichia coli, EPEC adherence factor (EAF), intimin (Eae), enterohemolysin (EntHly) and hemolysin (Hly) in 53 isolates of E. tarda from humans and fish from several countries. All isolates were negative for all genes investigated by PCR. Adhesion to and invasion of HeLa cells were determined by using the unusually short incubation time of 1h or 30 min. All isolates adhered and invaded in these tests. Finally, a random amplified polymorphic DNA (RAPD) test distinguished, with a few exceptions, isolates of human and fish origin.
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Affiliation(s)
- C Nucci
- Department of Microbiology and Immunology, Institute of Biology, University of Campinas, SP, Campinas, Brazil
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19
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Andrade A, Girón JA, Amhaz JMK, Trabulsi LR, Martinez MB. Expression and characterization of flagella in nonmotile enteroinvasive Escherichia coli isolated from diarrhea cases. Infect Immun 2002; 70:5882-6. [PMID: 12228323 PMCID: PMC128341 DOI: 10.1128/iai.70.10.5882-5886.2002] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We report that enteroinvasive Escherichia coli (EIEC) serotypes considered to be nonmotile produce an unusually large (77 kDa) flagellin that is assembled into functional flagellum filaments that allow the bacteria to swim in modified motility agar. The EIEC flagellin showed N-terminal identity to most common enterobacterial flagellins, especially those of the E. coli H7 serotype. These data are important in terms of the epidemiology, evolution, and biology of EIEC.
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Affiliation(s)
- Agda Andrade
- Departamento de Analises Clinicas e Toxicologicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, São Paulo, Brazil
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20
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Uphoff HU, Felske A, Fehr W, Wagner-Döbler I. The microbial diversity in picoplankton enrichment cultures: a molecular screening of marine isolates. FEMS Microbiol Ecol 2001; 35:249-258. [PMID: 11311435 DOI: 10.1111/j.1574-6941.2001.tb00810.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Picoplankton bacteria from a North Sea water sample were cultured under a variety of different conditions (nutrients, temperature, light, agitation, adhesion). Fluorescent in situ hybridization (FISH) analysis of the enrichments showed complex communities which were dominated by gamma-Proteobacteria or beta-Proteobacteria, followed by alpha-Proteobacteria and bacteria from the Cytophaga/Flavobacterium/Bacteroides (CFB) cluster. Among 410 isolates, a high degree of diversity was found, both with respect to colony color and morphology and with respect to genetic diversity. Isolated bacteria were classified into the main taxa by a special PCR approach, termed signature PCR (SIG-PCR). It was based on an oligo primer mixture targeting 16S rDNA which yielded PCR products of taxon-specific lengths. Again, gamma-Proteobacteria dominated (48%), followed by alpha-Proteobacteria (20%). beta-Proteobacteria were rarely isolated (eight strains of 410). The CFB cluster comprised the second largest phylum (14%), and 7.5% of all isolates belonged to the high-GC Gram-positives. Thus, isolated bacteria were representative of enrichment communities with the exception of the beta-Proteobacteria, which were detected in high abundance in certain enrichments by FISH but not isolated, and the high-GC Gram-positives, which were cultivated but not detected by FISH. A genomic fingerprinting technique, randomly amplified polymorphic DNA, showed that among 58 CFB isolates only 18 identical genotypes were found, and among the 84 alpha-Proteobacteria only eight identical genotypes were present. The data show the enormous diversity of cultivated bacteria from picoplankton enrichment cultures of one North Sea water sample, which is only a small fraction of the total picoplankton community.
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Affiliation(s)
- H U. Uphoff
- National Research Center for Biotechnology (GBF), Division of Microbiology, Mascheroder Weg 1, D-38124, Braunschweig, Germany
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21
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Peixoto JC, Bando SY, Ordoñez JA, Botelho BA, Trabulsi LR, Moreira-Filho CA. Genetic differences between Escherichia coli O26 strains isolated in Brazil and in other countries. FEMS Microbiol Lett 2001; 196:239-44. [PMID: 11267786 DOI: 10.1111/j.1574-6968.2001.tb10571.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Genomic diversity among 34 strains of Escherichia coli belonging to different serotypes of the O26 serogroup -- encompassing strains from different geographical origins and Shiga toxin-negative Brazilian strains -- was evaluated through random amplified polymorphic DNA (RAPD) analysis. Our results indicate that Brazilian and non-Brazilian O26 strains fall under distinct but closely related differentiation clusters. RFLP-PCR analysis of the fliC gene sequence was done in order to identify the H(-) serotypes and served to confirm the clustering pattern obtained in the dendrogram generated from RAPD data. The epidemiological significance of these data is discussed.
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Affiliation(s)
- J C Peixoto
- Departamento de Immunologia, Instituto de Ciências Biomédicus da Universidade São Paolo, SP, Brazil
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22
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Girão DM, Bando SY, Girão VBDC, Moreira-Filho CA, Fracalanzza SEL, Trabulsi LR, Monteiro-Neto V. Characterization of typical and atypical enteropathogenic Escherichia coli (EPEC) strains of the classical O55 serogroup by RAPD analysis. ACTA ACUST UNITED AC 1999. [DOI: 10.1590/s0001-37141999000400013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
Abstract
The genetic diversity of 41 typical and atypical enteropathogenic Escherichia coli (EPEC) strains of the serogroup O55 was analyzed by using the random amplified polymorphic DNA (RAPD) method. All typical EPEC O55 strains were grouped in two clusters (A and C) and belonged to the serotype O55:H6, while cluster B included all atypical strains, which were of the serotype O55:H7. The three groups also included non-motile strains. RAPD may be a useful method for epidemiological studies on E. coli O55 infection.
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23
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Martinez MB, Whittan TS, McGraw EA, Rodrigues J, Trabulsi LR. Clonal relationship among invasive and non-invasive strains of enteroinvasive Escherichia coli serogroups. FEMS Microbiol Lett 1999; 172:145-51. [PMID: 10188242 DOI: 10.1111/j.1574-6968.1999.tb13462.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The genetic relatedness among 96 invasive Escherichia coli belonging to several serogroups and 13 non-invasive of several serotypes that share the same O antigen was investigated by multilocus enzyme electrophoresis analysis. The invasive strains were isolated in different parts of the world and most of them recovered from dysentery. Twenty-nine electrophoretic types were distinguished and the most invasive strains were found to belong to two major lineages. These results suggested that the invasive ability in these strains has evolved in divergent chromosomal backgrounds, presumably through the horizontal spread of plasmid-borne invasion genes. The maintenance of invasive phenotypes in separate lineages suggests that this ability confers a selective advantage to invasive strains.
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Affiliation(s)
- M B Martinez
- Faculdade de Ciencias Farmaceuticas, Departamento de Analises Clinicas e Toxicologicas, Universidade de Sao Paulo, Brazil.
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