1
|
Tsoumtsa Meda LL, Landraud L, Petracchini S, Descorps-Declere S, Perthame E, Nahori MA, Ramirez Finn L, Ingersoll MA, Patiño-Navarrete R, Glaser P, Bonnet R, Dussurget O, Denamur E, Mettouchi A, Lemichez E. The cnf1 gene is associated with an expanding Escherichia coli ST131 H30Rx/C2 subclade and confers a competitive advantage for gut colonization. Gut Microbes 2022; 14:2121577. [PMID: 36154446 PMCID: PMC9519008 DOI: 10.1080/19490976.2022.2121577] [Citation(s) in RCA: 0] [Impact Index Per Article: 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
Epidemiological projections point to acquisition of ever-expanding multidrug resistance (MDR) by Escherichia coli, a commensal of the digestive tract and a source of urinary tract pathogens. Bioinformatics analyses of a large collection of E. coli genomes from EnteroBase, enriched in clinical isolates of worldwide origins, suggest the Cytotoxic Necrotizing Factor 1 (CNF1)-toxin encoding gene, cnf1, is preferentially distributed in four common sequence types (ST) encompassing the pandemic E. coli MDR lineage ST131. This lineage is responsible for a majority of extraintestinal infections that escape first-line antibiotic treatment, with known enhanced capacities to colonize the gastrointestinal tract. Statistical projections based on this dataset point to a global expansion of cnf1-positive multidrug-resistant ST131 strains from subclade H30Rx/C2, accounting for a rising prevalence of cnf1-positive strains in ST131. Despite the absence of phylogeographical signals, cnf1-positive isolates segregated into clusters in the ST131-H30Rx/C2 phylogeny, sharing a similar profile of virulence factors and the same cnf1 allele. The suggested dominant expansion of cnf1-positive strains in ST131-H30Rx/C2 led us to uncover the competitive advantage conferred by cnf1 for gut colonization to the clinical strain EC131GY ST131-H30Rx/C2 versus cnf1-deleted isogenic strain. Complementation experiments showed that colon tissue invasion was compromised in the absence of deamidase activity on Rho GTPases by CNF1. Hence, gut colonization factor function of cnf1 was confirmed for another clinical strain ST131-H30Rx/C2. In addition, functional analysis of the cnf1-positive clinical strain EC131GY ST131-H30Rx/C2 and a cnf1-deleted isogenic strain showed no detectable impact of the CNF1 gene on bacterial fitness and inflammation during the acute phase of bladder monoinfection. Together these data argue for an absence of role of CNF1 in virulence during UTI, while enhancing gut colonization capacities of ST131-H30Rx/C2 and suggested expansion of cnf1-positive MDR isolates in subclade ST131-H30Rx/C2.
Collapse
Affiliation(s)
- Landry L. Tsoumtsa Meda
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, INSERM U1306, Unité des Toxines Bactériennes, Département de Microbiologie, Paris, France
| | - Luce Landraud
- Université Paris Cité et Université Sorbonne Paris Nord, INSERM U1137, IAME, Paris, France,Laboratoire Microbiologie-hygiène, AP-HP, Hôpital Louis Mourier, Colombes, France
| | - Serena Petracchini
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, INSERM U1306, Unité des Toxines Bactériennes, Département de Microbiologie, Paris, France
| | - Stéphane Descorps-Declere
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, INSERM U1306, Unité des Toxines Bactériennes, Département de Microbiologie, Paris, France,Institut Pasteur, Université Paris Cité, Bioinformatics and Biostatistics Hub, Paris, France
| | - Emeline Perthame
- Institut Pasteur, Université Paris Cité, Bioinformatics and Biostatistics Hub, Paris, France
| | - Marie-Anne Nahori
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, INSERM U1306, Unité des Toxines Bactériennes, Département de Microbiologie, Paris, France
| | - Laura Ramirez Finn
- Institut Pasteur, Department of Immunology, Mucosal Inflammation and Immunity group, Paris, France,Université Paris Cité, Institut Cochin, CNRS UMR8104, INSERM U1016, Paris, France
| | - Molly A. Ingersoll
- Institut Pasteur, Department of Immunology, Mucosal Inflammation and Immunity group, Paris, France,Université Paris Cité, Institut Cochin, CNRS UMR8104, INSERM U1016, Paris, France
| | - Rafael Patiño-Navarrete
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Unité Ecologie et Evolution de la Résistance aux Antibiotiques, Département de Microbiologie, Paris, France
| | - Philippe Glaser
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Unité Ecologie et Evolution de la Résistance aux Antibiotiques, Département de Microbiologie, Paris, France
| | - Richard Bonnet
- UMR INSERM U1071, INRA USC-2018, Université Clermont Auvergne, Clermont-Ferrand, France,Centre National de Référence de la Résistance aux Antibiotiques, Centre Hospitalier Universitaire, Clermont-Ferrand, France
| | - Olivier Dussurget
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Unité de Recherche Yersinia, Département de Microbiologie, Paris, France
| | - Erick Denamur
- Université Paris Cité et Université Sorbonne Paris Nord, INSERM U1137, IAME, Paris, France,AP-HP, Laboratoire de Génétique Moléculaire, Hôpital Bichat, Paris, France
| | - Amel Mettouchi
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, INSERM U1306, Unité des Toxines Bactériennes, Département de Microbiologie, Paris, France,Amel Mettouchi Institut Pasteur, Université Paris Cité, CNRS UMR6047, INSERM U1306, Unité des Toxines Bactériennes, Département de Microbiologie, 75015Paris, France
| | - Emmanuel Lemichez
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, INSERM U1306, Unité des Toxines Bactériennes, Département de Microbiologie, Paris, France,CONTACT Emmanuel Lemichez
| |
Collapse
|
2
|
Bidet P, Birgy A, Ouldali N, Béchet S, Levy C, Madhi F, Sobral E, Cohen R, Bonacorsi S. Comparative genomic analysis of ESBL-producing Escherichia coli from faecal carriage and febrile urinary tract infection in children: a prospective multicentre study. JAC Antimicrob Resist 2022; 4:dlac056. [PMID: 35611261 PMCID: PMC9123598 DOI: 10.1093/jacamr/dlac056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 05/02/2022] [Indexed: 11/26/2022] Open
Abstract
Background The reliability of ESBL-producing Escherichia coli (ESBL-Ec) faecal carriage monitoring to guide probabilistic treatment of febrile urinary tract infection (FUTI) in children remains unclear. Objectives To compare the genomic characteristics of ESBL-Ec isolates from faecal carriage and FUTI to assess their correlation and identify a FUTI-associated virulence profile. Methods We conducted a prospective multicentre hospital and ambulatory-based study. We analysed the genotypes and virulence factors of both faecal and FUTI ESBL-Ec by whole genome sequencing. Correlations were assessed by non-parametric Spearman coefficient and virulence factors were assessed by chi-squared tests with Bonferroni correction. Results We included 218 ESBL-Ec causing FUTI and 154 ESBL-Ec faecal carriage isolates. The most frequent ST was ST131 (44%) in both collections. We found high correlation between carriage and ESBL-Ec FUTI regarding genes/alleles (rho = 0.88, P < 0.0001) and combinations of virulence genes, MLST and serotypes (rho = 0.90, P < 0.0001, rho = 0.99, P = 0.0003, rho = 0.97, P = 0.005 respectively). Beside this strong correlation, we found five genes that were significantly associated with FUTI (papC, papGII, hlyC, hek and traJ). The strongest association with FUTI was found with adhesin gene allele papGII (54% in FUTI versus 16% in carriage) and for papGII and gene traJ alone or in combination (63% versus 24%). Conclusions The genomic profile of ESBL-Ec causing FUTI in children strongly correlates with faecal carriage isolates except for a few genes. The presence of papGII and/or traJ in a previously identified carriage strain could be used as a marker of uropathogenicity and may guide the empirical antimicrobial choice in subsequent FUTI.
Collapse
Affiliation(s)
- Philippe Bidet
- Université Paris Cité, IAME, INSERM, F-75018 Paris, France
- Service de Microbiologie, Centre National de Référence associé pour Escherichia coli, Hôpital Robert-Debré, AP-HP, Paris, France
| | - André Birgy
- Université Paris Cité, IAME, INSERM, F-75018 Paris, France
- Service de Microbiologie, Centre National de Référence associé pour Escherichia coli, Hôpital Robert-Debré, AP-HP, Paris, France
| | - Naim Ouldali
- Association Clinique Thérapeutique Infantile du Val de Marne (ACTIV), Créteil, France
- Service de Pédiatrie Générale, Hôpital Robert-Debré, AP-HP, Paris, France
| | - Stéphane Béchet
- Association Clinique Thérapeutique Infantile du Val de Marne (ACTIV), Créteil, France
| | - Corinne Levy
- Association Clinique Thérapeutique Infantile du Val de Marne (ACTIV), Créteil, France
- Université Paris Est, IMRB-GRC GEMINI, Créteil, France
- GPIP (Groupe de Pathologie Infectieuse Pédiatrique) de la SFP (Société Française de Pédiatrie), Paris, France
| | - Fouad Madhi
- Association Clinique Thérapeutique Infantile du Val de Marne (ACTIV), Créteil, France
- Université Paris Est, IMRB-GRC GEMINI, Créteil, France
- GPIP (Groupe de Pathologie Infectieuse Pédiatrique) de la SFP (Société Française de Pédiatrie), Paris, France
- Service de Pédiatrie Générale, Centre Hospitalier Intercommunal de Créteil, Créteil, France
| | - Elsa Sobral
- Association Clinique Thérapeutique Infantile du Val de Marne (ACTIV), Créteil, France
| | - Robert Cohen
- Association Clinique Thérapeutique Infantile du Val de Marne (ACTIV), Créteil, France
- Université Paris Est, IMRB-GRC GEMINI, Créteil, France
- GPIP (Groupe de Pathologie Infectieuse Pédiatrique) de la SFP (Société Française de Pédiatrie), Paris, France
| | - Stéphane Bonacorsi
- Université Paris Cité, IAME, INSERM, F-75018 Paris, France
- Service de Microbiologie, Centre National de Référence associé pour Escherichia coli, Hôpital Robert-Debré, AP-HP, Paris, France
| |
Collapse
|
3
|
Desvaux M, Dalmasso G, Beyrouthy R, Barnich N, Delmas J, Bonnet R. Pathogenicity Factors of Genomic Islands in Intestinal and Extraintestinal Escherichia coli. Front Microbiol 2020; 11:2065. [PMID: 33101219 PMCID: PMC7545054 DOI: 10.3389/fmicb.2020.02065] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 08/05/2020] [Indexed: 12/20/2022] Open
Abstract
Escherichia coli is a versatile bacterial species that includes both harmless commensal strains and pathogenic strains found in the gastrointestinal tract in humans and warm-blooded animals. The growing amount of DNA sequence information generated in the era of "genomics" has helped to increase our understanding of the factors and mechanisms involved in the diversification of this bacterial species. The pathogenic side of E. coli that is afforded through horizontal transfers of genes encoding virulence factors enables this bacterium to become a highly diverse and adapted pathogen that is responsible for intestinal or extraintestinal diseases in humans and animals. Many of the accessory genes acquired by horizontal transfers form syntenic blocks and are recognized as genomic islands (GIs). These genomic regions contribute to the rapid evolution, diversification and adaptation of E. coli variants because they are frequently subject to rearrangements, excision and transfer, as well as to further acquisition of additional DNA. Here, we review a subgroup of GIs from E. coli termed pathogenicity islands (PAIs), a concept defined in the late 1980s by Jörg Hacker and colleagues in Werner Goebel's group at the University of Würzburg, Würzburg, Germany. As with other GIs, the PAIs comprise large genomic regions that differ from the rest of the genome by their G + C content, by their typical insertion within transfer RNA genes, and by their harboring of direct repeats (at their ends), integrase determinants, or other mobility loci. The hallmark of PAIs is their contribution to the emergence of virulent bacteria and to the development of intestinal and extraintestinal diseases. This review summarizes the current knowledge on the structure and functional features of PAIs, on PAI-encoded E. coli pathogenicity factors and on the role of PAIs in host-pathogen interactions.
Collapse
Affiliation(s)
- Mickaël Desvaux
- Université Clermont Auvergne, INRAE, MEDiS, Clermont-Ferrand, France
| | - Guillaume Dalmasso
- UMR Inserm 1071, USC-INRAE 2018, M2iSH, Université Clermont Auvergne, Clermont-Ferrand, France
| | - Racha Beyrouthy
- UMR Inserm 1071, USC-INRAE 2018, M2iSH, Université Clermont Auvergne, Clermont-Ferrand, France
- Laboratoire de Bactériologie, CHU Clermont-Ferrand, Clermont-Ferrand, France
| | - Nicolas Barnich
- UMR Inserm 1071, USC-INRAE 2018, M2iSH, Université Clermont Auvergne, Clermont-Ferrand, France
| | - Julien Delmas
- UMR Inserm 1071, USC-INRAE 2018, M2iSH, Université Clermont Auvergne, Clermont-Ferrand, France
- Laboratoire de Bactériologie, CHU Clermont-Ferrand, Clermont-Ferrand, France
| | - Richard Bonnet
- UMR Inserm 1071, USC-INRAE 2018, M2iSH, Université Clermont Auvergne, Clermont-Ferrand, France
- Laboratoire de Bactériologie, CHU Clermont-Ferrand, Clermont-Ferrand, France
| |
Collapse
|
4
|
Distribution of Virulence and Antimicrobial Resistance Genes in Phylogenetic Groups of Escherichia coli Strains Isolated from Mexican Patients with Urinary Infection. Jundishapur J Microbiol 2019. [DOI: 10.5812/jjm.83711] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
|
5
|
Khan ER, Aung MS, Paul SK, Ahmed S, Haque N, Ahamed F, Sarkar SR, Roy S, Rahman MM, Mahmud MC, Hossain MA, Urushibara N, Kawaguchiya M, Sumi A, Kobayashi N. Prevalence and Molecular Epidemiology of Clinical Isolates of Escherichia coli and Klebsiella pneumoniae Harboring Extended-Spectrum Beta-Lactamase and Carbapenemase Genes in Bangladesh. Microb Drug Resist 2018; 24:1568-1579. [DOI: 10.1089/mdr.2018.0063] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Affiliation(s)
- Emily Rahman Khan
- Department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh
| | - Meiji Soe Aung
- Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Shyamal Kumar Paul
- Department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh
| | - Salma Ahmed
- Department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh
| | - Nazia Haque
- Department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh
| | - Farid Ahamed
- Department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh
| | - Santana Rani Sarkar
- Department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh
| | - Sangjukta Roy
- Department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh
| | | | - Muhammad Chand Mahmud
- Department of Microbiology, President Abdul Hamid Medical College, Kishoreganj, Bangladesh
| | - Muhammad Akram Hossain
- Department of Microbiology and Mycology, National Institute of Preventive and Social Medicine, Dhaka, Bangladesh
| | - Noriko Urushibara
- Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Mitsuyo Kawaguchiya
- Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Ayako Sumi
- Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Nobumichi Kobayashi
- Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo, Japan
| |
Collapse
|
6
|
Aung MS, San N, Maw WW, San T, Urushibara N, Kawaguchiya M, Sumi A, Kobayashi N. Prevalence of Extended-Spectrum Beta-Lactamase and Carbapenemase Genes in Clinical Isolates of Escherichia coli in Myanmar: Dominance of bla NDM-5 and Emergence of bla OXA-181. Microb Drug Resist 2018; 24:1333-1344. [PMID: 29565227 DOI: 10.1089/mdr.2017.0387] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The increasing trend of Escherichia coli producing extended-spectrum beta-lactamases (ESBLs) and carbapenemases is a global public health concern. In this study, prevalence and molecular characteristics of E. coli harboring ESBL and carbapenemase genes were investigated for 426 isolates derived from various clinical specimens in a teaching hospital in Yangon, Myanmar, for the 1-year period beginning January 2016. A total of 157 isolates (36.9%) were ESBL producers and harbored CTX-M-1 group genes (146 isolates; blaCTX-M-15, blaCTX-M55) or CTX-M-9 group genes (11 isolates; blaCTX-M-14, blaCTX-M-27). Carbapenem resistance was detected in 35 isolates (8.2%), among which 26 isolates had carbapenemase genes encoding NDM-1 (2 isolates), NDM-4 (6 isolates), NDM-5 (14 isolates), NDM-7 (3 isolates), and OXA-181 (2 isolates). blaNDM-5 was identified in phylogenetic groups A, B1, and D isolates belonging to various genotypes (ST101, ST354, ST405, ST410, ST1196) associated with blaTEM-1, blaCTX-M-15, blaOXA-181, blaCMY-2, blaCMY-6, blaCMY-42, qnrB, qnrS, or aac6'-Ib-cr. While two isolates with blaOXA-181 belonged to phylogenetic group A-ST410, one isolate had also blaNDM-5, as well as blaCTX-M-15 and blaCMY-2, and the other harbored blaCMY-42 and aac6'-Ib-cr, showing different resistance patterns. Phylogenetic group B2 isolates examined were classified into mostly ST131 and had solely blaCTX-M-15 or blaCTX-M-27, harboring more virulence factors than other phylogenetic groups. The present study revealed high prevalence of ESBL genes represented by blaCTX-M-15 and dominance of blaNDM-5 among NDM genes, disseminating to various E. coli clones. Notably, carbapenemase gene encoding OXA-181 was first identified in Myanmar, suggesting its spread together with NDM genes.
Collapse
Affiliation(s)
- Meiji Soe Aung
- 1 Department of Hygiene, Sapporo Medical University School of Medicine , Sapporo, Japan
| | - Nilar San
- 2 Department of Microbiology, University of Medicine 2 , Yangon, Yangon, Myanmar
| | - Win Win Maw
- 2 Department of Microbiology, University of Medicine 2 , Yangon, Yangon, Myanmar
| | - Thida San
- 3 Yangon Children's Hospital , Department of Medical Services, Ministry of Health and Sports, Yangon, Myanmar
| | - Noriko Urushibara
- 1 Department of Hygiene, Sapporo Medical University School of Medicine , Sapporo, Japan
| | - Mitsuyo Kawaguchiya
- 1 Department of Hygiene, Sapporo Medical University School of Medicine , Sapporo, Japan
| | - Ayako Sumi
- 1 Department of Hygiene, Sapporo Medical University School of Medicine , Sapporo, Japan
| | - Nobumichi Kobayashi
- 1 Department of Hygiene, Sapporo Medical University School of Medicine , Sapporo, Japan
| |
Collapse
|
7
|
Zhang H, Susanto TT, Wan Y, Chen SL. Comprehensive mutagenesis of the fimS promoter regulatory switch reveals novel regulation of type 1 pili in uropathogenic Escherichia coli. Proc Natl Acad Sci U S A 2016; 113:4182-7. [PMID: 27035967 PMCID: PMC4839427 DOI: 10.1073/pnas.1522958113] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Type 1 pili (T1P) are major virulence factors for uropathogenic Escherichia coli (UPEC), which cause both acute and recurrent urinary tract infections. T1P expression therefore is of direct relevance for disease. T1P are phase variable (both piliated and nonpiliated bacteria exist in a clonal population) and are controlled by an invertible DNA switch (fimS), which contains the promoter for the fim operon encoding T1P. Inversion of fimS is stochastic but may be biased by environmental conditions and other signals that ultimately converge at fimS itself. Previous studies of fimS sequences important for T1P phase variation have focused on laboratory-adapted E coli strains and have been limited in the number of mutations or by alteration of the fimS genomic context. We surmounted these limitations by using saturating genomic mutagenesis of fimS coupled with accurate sequencing to detect both mutations and phase status simultaneously. In addition to the sequences known to be important for biasing fimS inversion, our method also identifies a previously unknown pair of 5' UTR inverted repeats that act by altering the relative fimA levels to control phase variation. Thus we have uncovered an additional layer of T1P regulation potentially impacting virulence and the coordinate expression of multiple pilus systems.
Collapse
Affiliation(s)
- Huibin Zhang
- Infectious Diseases Group, Genome Institute of Singapore, Singapore 138672
| | - Teodorus T Susanto
- Stem Cell and Development, Genome Institute of Singapore, Singapore 138672
| | - Yue Wan
- Stem Cell and Development, Genome Institute of Singapore, Singapore 138672
| | - Swaine L Chen
- Infectious Diseases Group, Genome Institute of Singapore, Singapore 138672; Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119074
| |
Collapse
|
8
|
Jajarmi M, Ghanbarpour R, Sharifi H, Golchin M. Distribution Pattern of EcoR Phylogenetic Groups Among Shiga Toxin-Producing and Enteropathogenic Escherichia coli Isolated From Healthy Goats. INTERNATIONAL JOURNAL OF ENTERIC PATHOGENS 2015. [DOI: 10.17795/ijep27971] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
|
9
|
Yahiaoui M, Robin F, Bakour R, Hamidi M, Bonnet R, Messai Y. Antibiotic Resistance, Virulence, and Genetic Background of Community-Acquired Uropathogenic Escherichia coli from Algeria. Microb Drug Resist 2015; 21:516-26. [PMID: 26430940 DOI: 10.1089/mdr.2015.0045] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The aim of the study was to investigate antibiotic resistance mechanisms, virulence traits, and genetic background of 150 nonrepetitive community-acquired uropathogenic Escherichia coli (CA-UPEC) from Algeria. A rate of 46.7% of isolates was multidrug resistant. bla genes detected were blaTEM (96.8% of amoxicillin-resistant isolates), blaCTX-M-15 (4%), overexpressed blaAmpC (4%), blaSHV-2a, blaTEM-4, blaTEM-31, and blaTEM-35 (0.7%). All tetracycline-resistant isolates (51.3%) had tetA and/or tetB genes. Sulfonamides and trimethoprim resistance genes were sul2 (60.8%), sul1 (45.9%), sul3 (6.7%), dfrA14 (25.4%), dfrA1 (18.2%), dfrA12 (16.3%), and dfrA25 (5.4%). High-level fluoroquinolone resistance (22.7%) was mediated by mutations in gyrA (S83L-D87N) and parC (S80I-E84G/V or S80I) genes. qnrB5, qnrS1, and aac(6')-Ib-cr were rare (5.3%). Class 1 and/or class 2 integrons were detected (40.7%). Isolates belonged to phylogroups B2+D (50%), A+B1 (36%), and F+C+Clade I (13%). Most of D (72.2%) and 38.6% of B2 isolates were multidrug resistant; they belong to 14 different sequence types, including international successful ST131, ST73, and ST69, reported for the first time in the community in Algeria and new ST4494 and ST4529 described in this study. Besides multidrug resistance, B2 and D isolates possessed virulence factors of colonization, invasion, and long-term persistence. The study highlighted multidrug-resistant CA-UPEC with high virulence traits and an epidemic genetic background.
Collapse
Affiliation(s)
- Merzouk Yahiaoui
- 1 Laboratory of Cellular and Molecular Biology, Faculty of Biological Sciences, University of Sciences and Technology Houari Boumediene , Algiers, Algeria
| | - Frédéric Robin
- 2 CHU Clermont-Ferrand, Laboratoire de Bactériologie , Clermont-Ferrand, France .,3 Clermont Université, Université d'Auvergne , Evolution des Bactéries Pathogènes et Susceptibilité de l'Hôte, Clermont-Ferrand, France
| | - Rabah Bakour
- 1 Laboratory of Cellular and Molecular Biology, Faculty of Biological Sciences, University of Sciences and Technology Houari Boumediene , Algiers, Algeria
| | | | - Richard Bonnet
- 2 CHU Clermont-Ferrand, Laboratoire de Bactériologie , Clermont-Ferrand, France .,3 Clermont Université, Université d'Auvergne , Evolution des Bactéries Pathogènes et Susceptibilité de l'Hôte, Clermont-Ferrand, France
| | - Yamina Messai
- 1 Laboratory of Cellular and Molecular Biology, Faculty of Biological Sciences, University of Sciences and Technology Houari Boumediene , Algiers, Algeria
| |
Collapse
|
10
|
Ahmed S, Kawaguchiya M, Ghosh S, Paul SK, Urushibara N, Mahmud C, Nahar K, Hossain MA, Kobayashi N. Drug resistance and molecular epidemiology of aerobic bacteria isolated from puerperal infections in Bangladesh. Microb Drug Resist 2015; 21:297-306. [PMID: 25555043 DOI: 10.1089/mdr.2014.0219] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Puerperal infection is a common complication during postnatal period in developing countries. Bacterial species, drug resistance, and genetic characteristics were investigated for a total of 470 isolates from puerperal infections in Bangladesh for a 2-year period (2010-2012). The most common species was Escherichia coli (n=98), followed by Enterococcus faecalis (n=54), Staphylococcus haemolyticus (n=33), Proteus mirabilis (n=32), Staphylococcus aureus (n=27), Klebsiella pneumoniae (n=22), and Enterobacter cloacae (n=21). S. aureus and Acinetobacter baumannii were isolated at a higher frequency from wound infections after cesarean section, while E. coli, E. cloacae, and K. pneumoniae were isolated from community-acquired endometritis and urinary tract infections. Resistance to third-generation cephalosporins was frequent for Enterobacteriacae, and was mainly mediated by blaCTX-M-1 group beta-lactamases. The CTX-M gene in E. coli from the four phylogroups was identified as blaCTX-M-15, and phylogroup B2 isolates with blaCTX-M-15 were classified into ST131 with O25b allele, harboring aac(6')-Ib-cr and various virulence factors. Carbapenemase genes blaNDM-1 and blaNDM-7 were identified in one isolate each of phylogroup A E. coli. Methicillin-resistant S. aureus isolates had type IV or V SCCmec, including isolates of ST361 (CC672), which is related to an emerging ST672 clone in the Indian subcontinent. This study revealed the recent epidemiological status of aerobic bacteria causing puerperal infections in Bangladesh, providing useful information to improve clinical practice and infection control.
Collapse
Affiliation(s)
- Salma Ahmed
- 1Department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh
| | - Mitsuyo Kawaguchiya
- 2Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Souvik Ghosh
- 2Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo, Japan.,3Department of Biomedical Sciences, Ross University School of Veterinary Medicine, St. Kitts, West Indies
| | - Shyamal Kumar Paul
- 1Department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh
| | - Noriko Urushibara
- 2Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Chand Mahmud
- 1Department of Microbiology, Mymensingh Medical College, Mymensingh, Bangladesh
| | - Kamrun Nahar
- 4Department of Gynecology and Obstetrics, Mymensingh Medical College, Mymensingh, Bangladesh
| | | | - Nobumichi Kobayashi
- 2Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo, Japan
| |
Collapse
|
11
|
Acquisition of a pathogenicity island in an Escherichia coli clinical isolate causing febrile urinary tract infection. Eur J Clin Microbiol Infect Dis 2011; 30:1543-50. [DOI: 10.1007/s10096-011-1258-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2010] [Accepted: 03/28/2011] [Indexed: 10/18/2022]
|
12
|
Pathogenicity island markers, virulence determinants malX and usp, and the capacity of Escherichia coli to persist in infants' commensal microbiotas. Appl Environ Microbiol 2011; 77:2303-8. [PMID: 21317254 DOI: 10.1128/aem.02405-10] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Virulence-associated genes in bacteria are often located on chromosomal regions, termed pathogenicity islands (PAIs). Several PAIs are found in Escherichia coli strains that cause extraintestinal infections, but their role in commensal bowel colonization is unknown. Resident strains are enriched in adhesins (P fimbriae and type 1 fimbriae), capsular antigens (K1 and K5), hemolysin, and aerobactin and mostly belong to phylogenetic group B2. Here, we investigated whether six pathogenicity islands and the virulence determinants malX and usp are associated with fitness of E. coli in the infant bowel microbiota. E. coli strains isolated from stools of 130 Swedish infants during the first year of life were examined for their carriage of PAI markers, malX, and usp by PCR. Carriage was related to strain persistence: long-term colonizers (≥12 months) carried significantly more of PAI II from strain CFT703 (II(CFT703)), IV(536,) and II(J96) and malX and usp than intermediate colonizers (1 to 11 months) and transient strains (<3 weeks). The accumulation of PAI markers in each individual strain correlated positively with its time of persistence in the colon. Phylogenetic group B2 accounted for 69% of long-term colonizers, 46% of intermediate colonizers and 14% of transient strains. These results support the hypothesis that some bacterial traits contributing to extraintestinal infections have in fact evolved primarily because they increase the fitness of E. coli in its natural niche, the colon; accordingly, they may be regarded as fitness islands in the gut.
Collapse
|
13
|
Phylogenetic groups and pathogenicity island markers in fecal Escherichia coli isolates from asymptomatic humans in China. Appl Environ Microbiol 2010; 76:6698-700. [PMID: 20709835 DOI: 10.1128/aem.00707-10] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The study of phylogenetic groups and pathogenicity island (PAI) markers in commensal Escherichia coli strains from asymptomatic Chinese people showed that group A strains are the most common and that nearly half of all fecal strains which were randomly selected harbor PAIs.
Collapse
|
14
|
Schwan WR, Briska A, Stahl B, Wagner TK, Zentz E, Henkhaus J, Lovrich SD, Agger WA, Callister SM, DuChateau B, Dykes CW. Use of optical mapping to sort uropathogenic Escherichia coli strains into distinct subgroups. MICROBIOLOGY-SGM 2010; 156:2124-2135. [PMID: 20378655 PMCID: PMC3068680 DOI: 10.1099/mic.0.033977-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Optical maps were generated for 33 uropathogenic Escherichia coli (UPEC) isolates. For individual genomes, the NcoI restriction fragments aligned into a unique chromosome map for each individual isolate, which was then compared with the in silico restriction maps of all of the sequenced E. coli and Shigella strains. All of the UPEC isolates clustered separately from the Shigella strains as well as the laboratory and enterohaemorrhagic E. coli strains. Moreover, the individual strains appeared to cluster into distinct subgroups based on the dendrogram analyses. Phylogenetic grouping of these 33 strains showed that 32/33 were the B2 subgroup and 1/33 was subgroup A. To further characterize the similarities and differences among the 33 isolates, pathogenicity island (PAI), haemolysin and virulence gene comparisons were performed. A strong correlation was observed between individual subgroups and virulence factor genes as well as haemolysis activity. Furthermore, there was considerable conservation of sequenced-strain PAIs in the specific subgroups. Strains with different antibiotic-resistance patterns also appeared to sort into separate subgroups. Thus, the optical maps distinguished the UPEC strains from other E. coli strains and further subdivided the strains into distinct subgroups. This optical mapping procedure holds promise as an alternative way to subgroup all E. coli strains, including those involved in infections outside of the intestinal tract and epidemic strains with distinct patterns of antibiotic resistance.
Collapse
|
15
|
Abstract
The urinary tract is among the most common sites of bacterial infection, and Escherichia coli is by far the most common species infecting this site. Individuals at high risk for symptomatic urinary tract infection (UTI) include neonates, preschool girls, sexually active women, and elderly women and men. E. coli that cause the majority of UTIs are thought to represent only a subset of the strains that colonize the colon. E. coli strains that cause UTIs are termed uropathogenic E. coli (UPEC). In general, UPEC strains differ from commensal E. coli strains in that the former possess extragenetic material, often on pathogenicity-associated islands (PAIs), which code for gene products that may contribute to bacterial pathogenesis. Some of these genes allow UPEC to express determinants that are proposed to play roles in disease. These factors include hemolysins, secreted proteins, specific lipopolysaccharide and capsule types, iron acquisition systems, and fimbrial adhesions. The current dogma of bacterial pathogenesis identifies adherence, colonization, avoidance of host defenses, and damage to host tissues as events vital for achieving bacterial virulence. These considerations, along with analysis of the E. coli CFT073, UTI89, and 536 genomes and efforts to identify novel virulence genes should advance the field significantly and allow for the development of a comprehensive model of pathogenesis for uropathogenic E. coli.Further study of the adaptive immune response to UTI will be especially critical to refine our understanding and treatment of recurrent infections and to develop vaccines.
Collapse
|
16
|
Bonacorsi S, Bidet P, Mahjoub F, Mariani-Kurkdjian P, Ait-Ifrane S, Courroux C, Bingen E. Semi-automated rep-PCR for rapid differentiation of major clonal groups of Escherichia coli meningitis strains. Int J Med Microbiol 2009; 299:402-9. [PMID: 19451030 DOI: 10.1016/j.ijmm.2009.04.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2009] [Revised: 03/20/2009] [Accepted: 04/18/2009] [Indexed: 10/20/2022] Open
Abstract
DiversiLab, a semi-automated repetitive-sequence-based PCR (rep-PCR) device, is a highly integrated platform designed for rapid bacterial genotyping. Here, we evaluated the capacity of the DiversiLab system to determine the genetic relatedness of Escherichia coli neonatal meningitis (ECNM) strains and to identify clonal groups. We analyzed 80 isolates representative of the diversity of ECNM strains in Europe and North America and 52 E. coli reference (ECOR) strains belonging to phylogenetic groups A, D, and B2. All the strains had previously been characterized by means of multilocus sequence typing (MLST). The DiversiLab dendrogram clustered all but 8 of the strains according to their phylogenetic groups. After defining a rep-PCR type complex (RPTc) based on an average similarity threshold of 95% between rep-PCR types, we observed excellent agreement between RPTc and sequence type complexes (STc) in groups D and B2. In group A, rep-PCR typing was more discriminative than MLST, dividing the 25 ECOR group A strains into 19 RPTc, compared to only 10 STc. In the highly virulent clonal group B2(1), mainly composed of O1, O2, O18, and O45:K1 strains, the DiversiLab system individualized a particular subgroup of O2:K1 strains. In addition, among O18:K1 strains the system identified a particular genetic background associated with pathogenicity island II(J96)-like domains. Thus, the DiversiLab system is a rapid and powerful tool for identifying and discriminating clonal groups among ECNM strains.
Collapse
Affiliation(s)
- Stéphane Bonacorsi
- Laboratoire d'études de génétique bactérienne dans les infections de l'enfant (EA 3105), Université Denis Diderot-Paris 7, France
| | | | | | | | | | | | | |
Collapse
|
17
|
Virulence factors in urinary Escherichia coli strains: phylogenetic background and quinolone and fluoroquinolone resistance. J Clin Microbiol 2007; 46:480-7. [PMID: 18057134 DOI: 10.1128/jcm.01488-07] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Quinolone- and fluoroquinolone-resistant Escherichia coli strains harbor fewer virulence factors than susceptible strains. The reasons underlying this correlation are incompletely understood. We investigated the phylogenetic background, the presence of the papC, hlyA, and cnf1 (pathogenicity island II(J96)-associated), fimA, iss, and iutA genes, and the presence of type 1 fimbriae, P fimbriae, and hemolysin in 243 urinary E. coli isolates resistant only to quinolones (8%), resistant to both quinolones and fluoroquinolones (51%), or susceptible to both drugs (41%). Group B2 accounted for 56% of the isolates, showing a significantly higher prevalence among fluoroquinolone-susceptible strains than among resistant strains (65% versus 50% [P = 0.03]). hly and cnf1 were significantly more associated with susceptibility (P < 0.001) and with group B2 (P < 0.001 for group B2 versus groups A and D). However, within group B2, fluoroquinolone-resistant strains showed lower prevalences of papC, hlyA, and cnf1 than their susceptible counterparts (P < 0.001). In contrast, the incidence of iutA appeared higher for refractory isolates, including group B2, than for susceptible isolates (P < 0.001). Only in group B2 did fluoroquinolone-resistant strains reveal a lesser ability to agglutinate Saccharomyces cerevisiae (7%) than quinolone-resistant (87%) and susceptible (80%) isolates, despite uniform possession of fimA genes. No similar contrast emerged for expression of hemolysin and P fimbriae. Mutations conferring quinolone and fluoroquinolone resistance may thus require a particular genetic background, not strictly correlated with phylogenetic groups. More interestingly, the mutational event itself can affect the expression of type 1 fimbriae, at least in the prevalent and complex B2 strains.
Collapse
|
18
|
Hannan TJ, Mysorekar IU, Chen SL, Walker JN, Jones JM, Pinkner JS, Hultgren SJ, Seed PC. LeuX tRNA-dependent and -independent mechanisms of Escherichia coli pathogenesis in acute cystitis. Mol Microbiol 2007; 67:116-28. [PMID: 18036139 DOI: 10.1111/j.1365-2958.2007.06025.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Uropathogenic Escherichia coli (UPEC) contain multiple horizontally acquired pathogenicity-associated islands (PAI) implicated in the pathogenesis of urinary tract infection. In a murine model of cystitis, type 1 pili-mediated bladder epithelial invasion and intracellular proliferation are key events associated with UPEC virulence. In this study, we examined the mechanisms by which a conserved PAI contributes to UPEC pathogenesis in acute cystitis. In the human UPEC strain UTI89, spontaneous excision of PAI II(UTI89) disrupts the adjacent leuX tRNA locus. Loss of wild-type leuX-encoded tRNA(5)(Leu) significantly delayed, but did not eliminate, FimB recombinase-mediated phase variation of type 1 pili. FimX, an additional FimB-like, leuX-independent recombinase, was also found to mediate type 1 pili phase variation. However, whereas FimX activity is relatively slow in vitro, it is rapid in vivo as a non-piliated strain lacking the other fim recombinases rapidly expressed type 1 pili upon experimental infection. Finally, we found that disruption of leuX, but not loss of PAI II(UTI89) genes, reduced bladder epithelial invasion and intracellular proliferation, independent of type 1 piliation. These findings indicate that the predominant mechanism for preservation of PAI II(UTI89) during the establishment of acute cystitis is maintenance of wild-type leuX, and not PAI II(UTI89) gene content.
Collapse
Affiliation(s)
- Thomas J Hannan
- Department of Molecular Microbiology and Microbial Pathogenesis, Washington University School of Medicine, St Louis, MO 63110, USA
| | | | | | | | | | | | | | | |
Collapse
|
19
|
Abstract
Extraintestinal pathogenic Escherichia coli (ExPEC) possesses virulence traits that allow it to invade, colonize, and induce disease in bodily sites outside of the gastrointestinal tract. Human diseases caused by ExPEC include urinary tract infections, neonatal meningitis, sepsis, pneumonia, surgical site infections, as well as infections in other extraintestinal locations. ExPEC-induced diseases represent a large burden in terms of medical costs and productivity losses. In addition to human illnesses, ExPEC strains also cause extraintestinal infections in domestic animals and pets. A commonality of virulence factors has been demonstrated between human and animal ExPEC, suggesting that the organisms are zoonotic pathogens. ExPEC strains have been isolated from food products, in particular from raw meats and poultry, indicating that these organisms potentially represent a new class of foodborne pathogens. This review discusses various aspects of ExPEC, including its presence in food products, in animals used for food or as companion pets; the diseases ExPEC can cause; and the virulence factors and virulence mechanisms that cause disease.
Collapse
Affiliation(s)
- James L Smith
- United States Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, Wyndmoor, Pennsylvania 19038, USA.
| | | | | |
Collapse
|
20
|
Kotlowski R, Bernstein CN, Sepehri S, Krause DO. High prevalence of Escherichia coli belonging to the B2+D phylogenetic group in inflammatory bowel disease. Gut 2007; 56:669-75. [PMID: 17028128 PMCID: PMC1942160 DOI: 10.1136/gut.2006.099796] [Citation(s) in RCA: 316] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND It is not clear which species of bacteria may be involved in inflammatory bowel disease (IBD). One way of determining which bacteria might be likely candidates is to use culture-independent methods to identify microorganisms that are present in diseased tissues but not in controls. AIMS (1) To assess the diversity of microbial communities of biopsy tissue using culture-independent methods; (2) to culture the bacteria found in the tissues of patients with IBD but not in the controls; (3) to identify potential virulence factors associated with cultured bacteria. METHODS 84 biopsy specimens were collected from 15 controls, 13 patients with Crohn's disease (CD) and 19 patients with ulcerative colitis (UC) from a population-based case-control study. Ribosomal intergenic spacer analysis (RISA) was conducted to identify unique DNA bands in tissues from patients with CD and UC that did not appear in controls. RESULTS RISA followed by DNA sequencing identified unique bands in biopsy specimens from patients with IBD that were classified as Escherichia coli. Targeted culture showed a significantly (p<0.05) higher number of Enterobacteriaceae in specimens from patients with IBD. The B2+D phylogenetic group, serine protease autotransporters (SPATE) and adherence factors were more likely to be associated with tissues from patients with UC and CD than with controls. CONCLUSIONS The abundance of Enterobacteriaceae is 3-4 logs higher in tissues of patients with IBD and the B2+D phylogenetic groups are more prevalent in patients with UC and CD. The B2+D phylogenetic groups are associated with SPATE and adherence factors and may have a significant role in disease aetiology.
Collapse
Affiliation(s)
- Roman Kotlowski
- Department of Animal Science, University of Manitoba, Winnipeg, Manitoba, Canada
| | | | | | | |
Collapse
|
21
|
Sorsa LJ, Feldmann F, Hildinger K, Dufke S, Schubert S. Characterization of four novel genomic regions of uropathogenic Escherichia coli highly associated with the extraintestinal virulent phenotype: a jigsaw puzzle of genetic modules. Int J Med Microbiol 2007; 297:83-95. [PMID: 17280868 DOI: 10.1016/j.ijmm.2006.11.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2006] [Revised: 09/21/2006] [Accepted: 11/21/2006] [Indexed: 01/18/2023] Open
Abstract
Extraintestinal pathogenic Escherichia coli (ExPEC) are a major cause of urinary tract infections, sepsis, and neonatal meningitis. A variety of virulence factors in these strains is encoded by mobile genetic elements, such as transposons or pathogenicity islands (PAIs). Using subtractive cloning of ExPEC genomes, we recently detected short DNA fragments, which were significantly associated with the extraintestinal virulent phenotype. In this study, we identified four novel genomic DNA regions of the highly virulent uropathogenic E. coli strain JS299 carrying these previously identified DNA fragments. Characterization of the partial sequences of the genomic DNA regions revealed complex DNA arrangements with variable genetic compositions regarding the G+C contents and codon usage patterns. The prevalence of 15 previously uncharacterized genes was determined in a collection of clinical ExPECs and commensal E. coli strains by means of DNA microarray analyses. From this, 13 novel DNA sequences were demonstrated to be significantly associated with extraintestinal virulent strains, and thus may represent new virulence traits. Beside genes predicted to play a role in metabolic functions, such as sucrose utilization (scr), we identified DNA sequences shared by both ExPEC and enteropathogenic E. coli (EPEC). These sequences were significantly more prevalent among ExPECs when compared to commensal E. coli isolates. Our results support the idea of a considerable genetic variability among ExPEC strains and suggest that the novel genomic determinants described in this study may contribute to the ExPEC virulence.
Collapse
Affiliation(s)
- Liisa Johanna Sorsa
- Max von Pettenkofer-Institut für Hygiene und Medizinische Mikrobiologie, Marchioninistr. 17, D-81377 München, Germany
| | | | | | | | | |
Collapse
|
22
|
Moritz RL, Welch RA. The Escherichia coli argW-dsdCXA genetic island is highly variable, and E. coli K1 strains commonly possess two copies of dsdCXA. J Clin Microbiol 2006; 44:4038-48. [PMID: 17088369 PMCID: PMC1698345 DOI: 10.1128/jcm.01172-06] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The genome sequences of Escherichia coli pathotypes reveal extensive genetic variability in the argW-dsdCXA island. Interestingly, the archetype E. coli K1 neonatal meningitis strain, strain RS218, has two copies of the dsdCXA genes for d-serine utilization at the argW and leuX islands. Because the human brain contains d-serine, an epidemiological study emphasizing K1 isolates surveyed the dsdCXA copy number and function. Forty of 41 (97.5%) independent E. coli K1 isolates could utilize d-serine. Southern blot hybridization revealed physical variability within the argW-dsdC region, even among 22 E. coli O18:K1:H7 isolates. In addition, 30 of 41 K1 strains, including 21 of 22 O18:K1:H7 isolates, had two dsdCXA loci. Mutational analysis indicated that each of the dsdA genes is functional in a rifampin-resistant mutant of RS218, mutant E44. The high percentage of K1 strains that can use d-serine is in striking contrast to our previous observation that only 4 of 74 (5%) isolates in the diarrheagenic E. coli (DEC) collection have this activity. The genome sequence of diarrheagenic E. coli isolates indicates that the csrRAKB genes for sucrose utilization are often substituted for dsdC and a portion of dsdX present at the argW-dsdCXA island of extraintestinal isolates. Among DEC isolates there is a reciprocal pattern of sucrose fermentation versus d-serine utilization. The ability to use d-serine is a trait strongly selected for among E. coli K1 strains, which have the ability to infect a wide range of extraintestinal sites. Conversely, diarrheagenic E. coli pathotypes appear to have substituted sucrose for d-serine as a potential nutrient.
Collapse
Affiliation(s)
- Rebecca L Moritz
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | | |
Collapse
|
23
|
Abstract
Urinary tract infection (UTI) is a common clinical syndrome in women. Most UTIs are caused by Escherichia coli. UTI has become a productive and accessible model system for studying the molecular details of how bacteria interact with mucosal surfaces and the nature of the host response. Important advances in the past year include the discovery of new virulence determinants; better understanding the pathogenic role of the ubiquitous motility organelle, the flagellum; and defining aspects of coordinate regulation of virulence determinants in the pathogenesis of UTI.
Collapse
Affiliation(s)
- Ann E Stapleton
- Department of Medicine, Division of Infectious Diseases, 1959 NE Pacific, Box 356523, University of Washington, Seattle, WA 98195, USA.
| |
Collapse
|