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Toro CS, Salazar JC, Montero DA, Ugalde JA, Díaz J, Cádiz LA, Henríquez T, García C, Díaz P, Camponovo R, Hermosilla G, Ulloa MT. Antimicrobial Resistance Dynamics in Chilean Shigella sonnei Strains Within Two Decades: Role of Shigella Resistance Locus Pathogenicity Island and Class 1 and Class 2 Integrons. Front Microbiol 2022; 12:794470. [PMID: 35185820 PMCID: PMC8854971 DOI: 10.3389/fmicb.2021.794470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 12/22/2021] [Indexed: 11/13/2022] Open
Abstract
Shigellosis is an enteric infectious disease in which antibiotic treatment is effective, shortening the duration of symptoms and reducing the excretion of the pathogen into the environment. Shigella spp., the etiologic agent, are considered emerging pathogens with a high public health impact due to the increase and global spread of multidrug-resistant (MDR) strains. Since Shigella resistance phenotype varies worldwide, we present an overview of the resistance phenotypes and associated genetic determinants present in 349 Chilean S. sonnei strains isolated during the periods 1995–1997, 2002–2004, 2008–2009, and 2010–2013. We detected a great variability in antibiotic susceptibility patterns, finding 300 (86%) MDR strains. Mobile genetic elements (MGE), such as plasmids, integrons, and genomic islands, have been associated with the MDR phenotypes. The Shigella resistance locus pathogenicity island (SRL PAI), which encodes for ampicillin, streptomycin, chloramphenicol, and tetracycline resistance genes, was detected by PCR in 100% of the strains isolated in 2008–2009 but was less frequent in isolates from other periods. The presence or absence of SRL PAI was also differentiated by pulsed-field gel electrophoresis. An atypical class 1 integron which harbors the blaOXA–1-aadA1-IS1 organization was detected as part of SRL PAI. The dfrA14 gene conferring trimethoprim resistance was present in 98.8% of the 2008–2009 isolates, distinguishing them from the SRL-positive strains isolated before that. Thus, it seems an SRL-dfrA14 S. sonnei clone spread during the 2008–2009 period and declined thereafter. Besides these, SRL-negative strains harboring class 2 integrons with or without resistance to nalidixic acid were detected from 2011 onward, suggesting the circulation of another clone. Whole-genome sequencing of selected strains confirmed the results obtained by PCR and phenotypic analysis. It is highlighted that 70.8% of the MDR strains harbored one or more of the MGE evaluated, while 15.2% lacked both SRL PAI and integrons. These results underscore the temporal dynamics of antimicrobial resistance in S. sonnei strains circulating in Chile, mainly determined by the spread of MGE conferring MDR phenotypes. Since shigellosis is endemic in Chile, constant surveillance of antimicrobial resistance phenotypes and their genetic basis is a priority to contribute to public health policies.
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Affiliation(s)
- Cecilia S. Toro
- Programa de Microbiología y Micología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile
- *Correspondence: Cecilia S. Toro,
| | - Juan Carlos Salazar
- Programa de Microbiología y Micología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile
| | - David A. Montero
- Programa Disciplinario de Inmunología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile
| | - Juan Antonio Ugalde
- C+, Research Center in Technologies for Society, School of Engineering, Universidad del Desarrollo, Santiago, Chile
- Millennium Initiative for Collaborative Research on Bacterial Resistance, Santiago, Chile
| | - Janepsy Díaz
- Departamento de Estudios Científicos, Instituto de Salud Pública de Chile, Santiago, Chile
| | - Leandro A. Cádiz
- Programa de Microbiología y Micología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile
| | - Tania Henríquez
- Programa de Microbiología y Micología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile
| | - Camila García
- Escuela de Tecnología Médica, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Patricia Díaz
- Programa de Microbiología y Micología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile
| | | | - Germán Hermosilla
- Programa de Microbiología y Micología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile
| | - María Teresa Ulloa
- Programa de Microbiología y Micología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile, Santiago, Chile
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Laboratory-based surveillance of Shigella spp. from human clinical cases in Colombia, 1997-2018. ACTA ACUST UNITED AC 2021; 41:65-78. [PMID: 33761190 PMCID: PMC8055590 DOI: 10.7705/biomedica.5113] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Indexed: 11/21/2022]
Abstract
INTRODUCTION Shigellosis is endemic in low-and middle-income countries, causing approximately 125 million episodes of diarrhea and leading to approximately 160 .000 deaths annually one-third of which is associated with children. OBJECTIVE To describe the characteristics and antimicrobial resistance profiles of Shigella species recovered in Colombia from 1997 to 2018. MATERIALS AND METHODS We received isolates from laboratories in 29 Colombian departments. We serotyped with specific antiserum and determined antimicrobial resistance and minimal inhibitory concentrations for ten antibiotics with Kirby-Bauer tests following the Clinical and Laboratory Standards Institute recommendations. RESULTS We analyzed 5,251 isolates of Shigella spp., most of them obtained from stools (96.4%); 2,511 (47.8%) were from children under five years of age. The two most common species were S. sonnei (55.1%) and S. flexneri (41.7%). The highest resistance rate was that of tetracycline (88.1%) followed by trimethoprim-sulfamethoxazole (79.3%) and ampicillin (65.5%); 50.8% of isolates were resistant to chloramphenicol, 43.6% to amoxicillin/clavulanic acid, and less than 1% to cefotaxime, ceftazidime, gentamicin, and ciprofloxacin. In S. sonnei, the most common resistance profile corresponded to trimethoprim-sulfamethoxazole (92%) whereas in S. flexneri the most common antibiotic profiles were multidrug resistance. CONCLUSIONS In Colombia, children under five years are affected by all Shigella species. These findings should guide funders and public health officials to make evidence based decisions for protection and prevention measures. The antimicrobial resistance characteristics found in this study underline the importance of combating the dissemination of the most frequently isolated species, S. sonnei and S. flexneri.
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Gonzales JC, Seribelli AA, Gomes CN, Dos Prazeres Rodrigues D, Campioni F, Passaglia J, da Silva P, Falcão JP. A high number of multidrug-resistant and predominant genetically related cluster of Shigella flexneri strains isolated over 34 years in Brazil. Braz J Microbiol 2020; 51:1563-1571. [PMID: 32710175 DOI: 10.1007/s42770-020-00332-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 06/29/2020] [Indexed: 11/26/2022] Open
Abstract
Shigella flexneri has been a major public health problem in developing countries. This work analyzed the frequency of 16 virulence genes, the genotypic diversity, and the antimicrobial resistance profiles of 130 S. flexneri strains isolated in Brazil. The ipaH gene was found in all the 130 strains. The frequencies of the other genes were variable ial (88.5%), sigA (82.3%), iuc (74.6%), virA (73%), pic (72.3%), virF (57.7%), sat (48.5%), ipaBCD (37%), sen (36%), set1A (35.4%), sepA (30%), set1B (30%), virB (14%), icsA (10%), and ipgD (5.4%). A total of 57 (43.8%) strains were multidrug-resistant. ERIC-PCR grouped 96 of the strains into a single cluster with ≥ 70.4% of similarity, 75 of these strains presented a similarity ≥ 80.9%. PFGE grouped 120 of the strains into a single cluster with 57.4% of similarity and 82 of these strains presented a similarity ≥ 70.6%. In conclusion, the high frequency of some virulence genes reinforces the pathogenic potential of the strains studied. The high rates of MDR strains are alarming once it may lead to failure when antimicrobial treatment is necessary. Genotype techniques reveled a major cluster with high genetic similarity including S. flexneri strains from the different Brazilian states and distinct years of isolation, showing that they probably emerged from a common ancestor.
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Affiliation(s)
- Júlia Cunha Gonzales
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo-USP, Av. do Café, s/no-Campus Universitário USP, Ribeirão Preto, SP, 14040-903, Brazil
| | - Amanda Aparecida Seribelli
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo-USP, Av. do Café, s/no-Campus Universitário USP, Ribeirão Preto, SP, 14040-903, Brazil
| | - Carolina Nogueira Gomes
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo-USP, Av. do Café, s/no-Campus Universitário USP, Ribeirão Preto, SP, 14040-903, Brazil
| | | | - Fábio Campioni
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo-USP, Av. do Café, s/no-Campus Universitário USP, Ribeirão Preto, SP, 14040-903, Brazil
| | - Jaqueline Passaglia
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo-USP, Av. do Café, s/no-Campus Universitário USP, Ribeirão Preto, SP, 14040-903, Brazil
| | - Paulo da Silva
- Instituto Adolfo Lutz de Ribeirão Preto, São Paulo, Brazil
| | - Juliana Pfrimer Falcão
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo-USP, Av. do Café, s/no-Campus Universitário USP, Ribeirão Preto, SP, 14040-903, Brazil.
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Gu B, Fan W, Qin T, Kong X, Dong C, Tan Z, Chen Y, Xu N, Ma P, Bao CJ, Qian H. Existence of virulence genes in clinical Shigella sonnei isolates from Jiangsu Province of China: a multicenter study. ANNALS OF TRANSLATIONAL MEDICINE 2019; 7:305. [PMID: 31475175 DOI: 10.21037/atm.2019.06.13] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Background The ability of Shigella to invade, colonizes, and eventually kill host cells is influenced by many virulence factors. The aims of this study were to assess the presence of 11 virulence genes of S. sonnei strains isolated in this country. Methods A total of 166 S. sonnei was collected from 13 cities of Jiangsu province through the provincial Centers for Disease Control (CDC) from 2010 to 2015 and then the distribution of virulence genes was detected by polymerase chain reaction (PCR) technology. Results Invasive virulence genes included ipaH and ial, in which the positive rate of ipaH was 100% while the positive rate of ial was 15.1% in S. sonnei. The classic pathway of regulating expression of Shigella virulence gene involved virF and virB gene, which positive rates were 33.7% and 24.1% respectively. The most common serine protease autotransporters of Enterobacteriaceae among S. sonnei were sigA (100%), followed by sepA (3.0%), sat (3.0%), pic (1.2%). Shigella enterotoxin genes include sen, set1A, set1B were found in 16.3%, 6.0% and 1.8% of the isolates, respectively. Conclusions This study provides baseline information on the distribution of virulence genes in clinical S. sonnei trains in Jiangsu province in China, which will be important for implementation of effective control strategies.
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Affiliation(s)
- Bing Gu
- Medical Technology School, Xuzhou Medical University, Xuzhou 221004, China.,Department of Laboratory Medicine, Affiliated Hospital of Xuzhou Medical University, Xuzhou 221002, China
| | - Wenting Fan
- Department of Laboratory Medicine, Affiliated Hospital of Xuzhou Medical University, Xuzhou 221002, China
| | - Tingting Qin
- Department of Laboratory Medicine, Affiliated Hospital of Xuzhou Medical University, Xuzhou 221002, China
| | - Xiaoxiao Kong
- Department of Acute Infectious Disease Prevention and Control, Jiangsu Provincial Center for Disease Prevention and Control, Nanjing 210029, China
| | - Chen Dong
- Department of Acute Infectious Disease Prevention and Control, Jiangsu Provincial Center for Disease Prevention and Control, Nanjing 210029, China
| | - Zhongming Tan
- Department of Acute Infectious Disease Prevention and Control, Jiangsu Provincial Center for Disease Prevention and Control, Nanjing 210029, China
| | - Ying Chen
- Medical Technology School, Xuzhou Medical University, Xuzhou 221004, China
| | - Nana Xu
- Medical Technology School, Xuzhou Medical University, Xuzhou 221004, China
| | - Ping Ma
- Department of Laboratory Medicine, Affiliated Hospital of Xuzhou Medical University, Xuzhou 221002, China.,Department of Acute Infectious Disease Prevention and Control, Jiangsu Provincial Center for Disease Prevention and Control, Nanjing 210029, China
| | - Chang-Jun Bao
- Medical Technology School, Xuzhou Medical University, Xuzhou 221004, China
| | - Huimin Qian
- Medical Technology School, Xuzhou Medical University, Xuzhou 221004, China
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Lopez-Canovas L, Martinez Benitez MB, Herrera Isidron JA, Flores Soto E. Pulsed Field Gel Electrophoresis: Past, present, and future. Anal Biochem 2019; 573:17-29. [PMID: 30826351 DOI: 10.1016/j.ab.2019.02.020] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 02/22/2019] [Accepted: 02/22/2019] [Indexed: 12/27/2022]
Abstract
Pulsed Field Gel Electrophoresis (PFGE) has been considered for many years the 'gold-standard' for characterizing many pathogenic organisms as well as for subtyping bacterial species causing infection outbreaks. This article reviews the basic principles of PFGE and it includes the main advantages and limitations of the different electrode configurations that have been used in PFGE equipment and their influence on the DNA electrophoretic separation. Remarkably, we summarize here the most relevant theoretical and practical aspects that we have learned for more than 20 years developing and using the miniaturized PFGE systems. We also discussed the theoretical aspects related to DNA migration in PFGE agarose gels. It served as the basis for simulating the DNA electrophoretic patterns in CHEF mini gels and mini-chambers during experimental design and optimization. A critical comparison between standard and miniaturized PFGE systems, as well as the enzymatic and non-enzymatic methods for intact immobilized DNA preparation, is provided throughout the review. The PFGE current applications, advantages, limitations and future challenges of the methodology are also discussed.
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Affiliation(s)
- Lilia Lopez-Canovas
- Postgraduate Program in Genomic Sciences, School of Science and Technology (CCyT), Autonomous University of Mexico City (UACM), Mexico City, Mexico.
| | - Maximo B Martinez Benitez
- Postgraduate Program in Genomic Sciences, School of Science and Technology (CCyT), Autonomous University of Mexico City (UACM), Mexico City, Mexico.
| | | | - Eduardo Flores Soto
- Academy of Biology, School of Sciences and Humanities, UACM, Mexico City, Mexico.
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Molecular methods for diversity assessment among xanthomonads of Bulgarian and Macedonian pepper. Braz J Microbiol 2018; 49 Suppl 1:246-259. [PMID: 29784602 PMCID: PMC6328724 DOI: 10.1016/j.bjm.2017.08.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 07/19/2017] [Accepted: 08/23/2017] [Indexed: 12/02/2022] Open
Abstract
Bacterial spot is an important disease of pepper in Bulgaria and Macedonia. For characterization of Xanthomonas species associated with bacterial spot, 161 strains were collected from various field pepper-growing regions. Among them, 131 strains were identified as Xanthomonas euvesicatoria and 30 as Xanthomonas vesicatoria using species-specific primers and polymerase chain reaction followed by restriction fragment length polymorphism analysis. To assess the genetic diversity of the strains, two methods (Random Amplified Polymorphic DNA and Repetitive Element Palindromic-Polymerase Chain Reaction) were applied. Discriminatory index was calculated and analysis of molecular variance was carried out. Combined random amplified polymorphic DNA analysis of the X. euvesicatoria strains with primers CUGEA-4 and CUGEA-6 had greater discriminative power (0.60) than repetitive element palindromic-polymerase chain reaction with ERIC and BOX A1R primers, which makes this method applicable for strain diversity evaluation. Discrimination among the X. vesicatoria strains was achieved by the use of ERIC primers and only for the Bulgarian strains. The results demonstrated that X. euvesicatoria was more diverse than X. vesicatoria and heterogeneity was observed mainly in the Bulgarian populations. According to the analysis of molecular variance, genetic variations in X. euvesicatoria were observed among and within populations from different regions, while the differences between the two countries were minor. Following the principal coordinates analysis, a relation between the climatic conditions of the regions and a genetic distance of the populations may be suggested.
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Seribelli AA, Frazão MR, Medeiros MIC, Stehling EG, Falcão JP. Molecular typing and occurrence of beta-lactam resistance genes of Shigella sonnei strains isolated from 1983 to 2014 in the São Paulo state of Brazil. Microbiol Immunol 2017; 61:547-553. [PMID: 29058340 DOI: 10.1111/1348-0421.12550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 10/03/2017] [Accepted: 10/19/2017] [Indexed: 11/29/2022]
Abstract
Shigella sonnei, which has generally been associated with dysentery in developed countries, has recently been emerging in developing countries. Specifically, in Brazil few published studies have that molecularly characterized this species. The aims of this study were to analyze the efficacy of typing using multiple-locus variable-number tandem-repeat analysis (MLVA), study the phylogeny by multi-locus sequence typing (MLST) and assess the presence of some beta-lactam resistance genes in S. sonnei strains isolated from human diarrhoeic faeces in the São Paulo State in Brazil between 1983 and 2014. Seventy-two such S. sonnei strains were typed by MLVA and grouped into two clusters. The discrimination index of MLVA was found to be 0.996. Twenty strains were typed by MLST as ST152. In addition, the blaTEM gene was detected in eight (72.7%) of the 11 S. sonnei strains that had previously been shown to be resistant to β-lactams. However, blaCTX-M-1group , blaCTX-M-9group and blaSHV genes were not found. MLVA results suggested the existence of two prevalent subtypes in the S. sonnei strains studied, confirming previous results. Moreover, MLVA efficiently discriminated monomorphic S. sonnei species. Because the S. sonnei strains studied belonged to clonal complex 152 and all isolates were typed as ST152, MLST is not a suitable method for studying the population structure of S. sonnei. Although, the rates of β-lactam resistance were not high in the present study, the frequency of blaTEM may represent a risk for patients receiving antimicrobial treatment. Taken together, the results provide better molecular characterization of this globally clinically important pathogen.
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Affiliation(s)
- Amanda Ap Seribelli
- School of Pharmaceutical Sciences of Ribeirão Preto, Department of Clinical Analyses, Toxicology and Food Science, University of São Paulo, Café Avenue, 14040-903, Brazil
| | - Miliane R Frazão
- School of Pharmaceutical Sciences of Ribeirão Preto, Department of Clinical Analyses, Toxicology and Food Science, University of São Paulo, Café Avenue, 14040-903, Brazil
| | | | - Eliana G Stehling
- School of Pharmaceutical Sciences of Ribeirão Preto, Department of Clinical Analyses, Toxicology and Food Science, University of São Paulo, Café Avenue, 14040-903, Brazil
| | - Juliana P Falcão
- School of Pharmaceutical Sciences of Ribeirão Preto, Department of Clinical Analyses, Toxicology and Food Science, University of São Paulo, Café Avenue, 14040-903, Brazil
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Miranda A, Ávila B, Díaz P, Rivas L, Bravo K, Astudillo J, Bueno C, Ulloa MT, Hermosilla G, Del Canto F, Salazar JC, Toro CS. Emergence of Plasmid-Borne dfrA14 Trimethoprim Resistance Gene in Shigella sonnei. Front Cell Infect Microbiol 2016; 6:77. [PMID: 27489797 PMCID: PMC4951496 DOI: 10.3389/fcimb.2016.00077] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 07/05/2016] [Indexed: 11/24/2022] Open
Abstract
The most common mechanism of trimethoprim (TMP)-resistance is the acquisition of dihydrofolate reductase enzyme resistant to this drug. Previous molecular characterization of TMP-genes resistance in Chilean isolates of Shigella sonnei searching for dfrA1 and dfrA8, showed solely the presence of dfrA8 (formerly dhfrIIIc). However, these genetic markers were absent in S. sonnei strains further isolated during an outbreak in 2009. To identify the TMP-resistance gene in these strains, a genomic DNA library from a TMP-resistant (TMPR) S. sonnei representative strain for the outbreak was used to clone, select and identify a TMP-resistance marker. The TMPR clone was sequenced by primer walking, identifying the presence of the dfrA14 gene in the sul2-strA'-dfrA14-‘strA-strB gene arrangement, harbored in a native 6779-bp plasmid. The same plasmid was isolated by transforming with a ~4.2 MDa plasmid extracted from several TMPRS. sonnei strains into Escherichia coli. This plasmid, named pABC-3, was present only in dfrA14-positive strains and was homologous to a previously described pCERC-1, but different due to the absence of an 11-bp repetitive unit. The distribution of dfrA1, dfrA8, and dfrA14 TMP-resistance genes was determined in 126 TMPRS. sonnei isolates. Most of the strains (96%) carried only one of the three TMP-resistance genes assessed. Thus, all strains obtained during the 2009-outbreak harbored only dfrA14, whereas, dfrA8 was the most abundant gene marker before outbreak and, after the outbreak dfrA1 seems have appeared in circulating strains. According to PFGE, dfrA14-positive strains were clustered in a genetically related group including some dfrA1- and dfrA8-positive strains; meanwhile other genetic group included most of the dfrA8-positive strains. This distribution also correlated with the isolation period, showing a dynamics of trimethoprim genetic markers prevalent in Chilean S. sonnei strains. To our knowledge, dfrA14 gene associated to a small non-conjugative plasmid was detected for the first time in Shigella. Apparently, the strain causing the outbreak must have been introduced, changing drastically the genetic distribution of trimethoprim resistance in Chilean S. sonnei strains.
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Affiliation(s)
- Alfonso Miranda
- Programa de Microbiología y Micología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile Santiago, Chile
| | - Bárbara Ávila
- Programa de Microbiología y Micología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile Santiago, Chile
| | - Patricia Díaz
- Programa de Microbiología y Micología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile Santiago, Chile
| | - Lina Rivas
- Programa de Microbiología y Micología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile Santiago, Chile
| | - Karen Bravo
- Programa de Microbiología y Micología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile Santiago, Chile
| | - Javier Astudillo
- Programa de Microbiología y Micología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile Santiago, Chile
| | - Constanza Bueno
- Programa de Microbiología y Micología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile Santiago, Chile
| | - María T Ulloa
- Programa de Microbiología y Micología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile Santiago, Chile
| | - Germán Hermosilla
- Programa de Microbiología y Micología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile Santiago, Chile
| | - Felipe Del Canto
- Programa de Microbiología y Micología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile Santiago, Chile
| | - Juan C Salazar
- Programa de Microbiología y Micología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile Santiago, Chile
| | - Cecilia S Toro
- Programa de Microbiología y Micología, Facultad de Medicina, Instituto de Ciencias Biomédicas, Universidad de Chile Santiago, Chile
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