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Liu B, Meng C, Han S, Li Q, Miao X, Wang Z, Xu C, Kang X, Jiao X, Pan Z. Development of a 1-step multiplex PCR assay for the detection of S. Enteritidis, S. Pullorum, S. Typhimurium, and S. Infantis associated with poultry production. Poult Sci 2024; 103:104043. [PMID: 39043031 DOI: 10.1016/j.psj.2024.104043] [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: 05/13/2024] [Revised: 06/23/2024] [Accepted: 06/24/2024] [Indexed: 07/25/2024] Open
Abstract
Salmonellosis in poultry is detrimental to the advancement of the breeding industry and poses hazards to human health. Approximately 2,600 Salmonella varieties exist, among which S. Enteritidis, S. Pullorum, S. Typhimurium, and S. Infantis are prevalent serotypes in the poultry industry in recent years. They can also infect humans by contaminating poultry eggs and meat. Therefore, identifying these serotypes is crucial for successful preventive and control interventions. The White-Kauffmann-Le Minor scheme is time-consuming and requires expensive reagents. Whole-genome sequencing (WGS) and other molecular biology techniques require skilled technical staff. In comparison, the polymerase chain reaction (PCR) is more accurate, rapid, and inexpensive, thus proving suitable for widespread application in the poultry industry. Here, we selected 4 specific primers: lygD, mdh, ipaJ, and SIN_02055, which correspond to detecting S. Enteritidis, S. Typhimurium, S. Pullorum, and S. Infantis, respectively. They were integrated into a 1-step multiplex PCR method. We optimized the PCR method by utilizing specificity test results to determine the optimal annealing temperature (57°C). The PCR method exhibited excellent sensitivity for genomic DNA and bacterial cultures. We used the developed method to determine 157 clinical Salmonella isolates from various stages of the poultry production chain. The results aligned with serotype data generated via WGS analysis, demonstrating the method's excellent accuracy. In conclusion, this study developed a 1-step multiplex PCR method that simultaneously identifies S. Enteritidis, S. Typhimurium, S. Pullorum, and S. Infantis, allowing routine mass detection in the grass-root poultry industry.
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Affiliation(s)
- Bowen Liu
- Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University, Yangzhou 225009, China
| | - Chuang Meng
- Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University, Yangzhou 225009, China
| | - Shunzi Han
- Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China
| | - Qing Li
- Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China
| | - Xinyuan Miao
- Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University, Yangzhou 225009, China
| | - Zhenyu Wang
- Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University, Yangzhou 225009, China
| | - Chen Xu
- Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University, Yangzhou 225009, China
| | - Xilong Kang
- Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University, Yangzhou 225009, China
| | - Xinan Jiao
- Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University, Yangzhou 225009, China
| | - Zhiming Pan
- Jiangsu Key Laboratory of Zoonosis/Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou 225009, China; Key Laboratory of Prevention and Control of Biological Hazard Factors (Animal Origin) for Agrifood Safety and Quality, Ministry of Agriculture of China, Yangzhou University, Yangzhou 225009, China; Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University, Yangzhou 225009, China.
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Vinueza-Burgos C, Hidalgo-Arellano L, Gómez-Coronado C, Medina-Santana JL, Cevallos-Almeida M. Prevalence, serovars, and risk factors associated with the presence of Salmonella in pork sold in public markets in Quito, Ecuador. F1000Res 2024; 12:1367. [PMID: 38882713 PMCID: PMC11176892 DOI: 10.12688/f1000research.138671.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/17/2024] [Indexed: 06/18/2024] Open
Abstract
Background Salmonella enterica are bacteria that include more than 2,500 serovars. Most of these serovars have been linked to human foodborne illnesses, mainly related to poultry and pigs. Thus, these animals are considered the reservoirs of many Salmonella serovars and strains related to antibiotic resistance. This study aimed to determine the prevalence, serovars, β-lactam resistance genes, and the risk factors associated with Salmonella enterica in pork commercialized in open markets of Quito city. Methods For this, 165 pork meat samples were taken from municipal markets in three areas in the city. These samples were microbiologically processed following the ISO 6579-2014 standardized method. The polymerase chain reaction (PCR) test was used to identify Salmonella serotyping and resistance genes. Strains not identified by PCR were typed by the Kauffman White Le Minor scheme. A multivariate analysis was performed to identify risk factors associated with the presence of the microorganism. Results Salmonella prevalence in pork was 9.1%. Identified serovars were 4, [5], 12: i:- (53.3%), Infantis (33.3%), and Derby (13.4%). Furthermore, the β-lactam resistance genes bla CTX-M-65 could be identified in three S. infantis isolates. Multivariate analysis showed that temperature (above 8°C) and cutting surfaces (wood) presented significant association values. Conclusions In conclusion, pork in traditional markets of Quito is contaminated with Salmonella enterica, whose main serovars pose a public health concern, and shows beta-lactam resistance.
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Affiliation(s)
- Christian Vinueza-Burgos
- Unidad de Investigación de Enfermedades Transmitidas por Alimentos y Resistencia a los Antimicrobianos (UNIETAR). Facultad de Medicina Veterinaria y Zootecnia, Universidad Central del Ecuador, Quito, Pichincha, Ecuador
| | - Luis Hidalgo-Arellano
- Laboratorio de Bacteriología y Micología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Central del Ecuador, Quito, Pichincha, Ecuador
| | - Carlos Gómez-Coronado
- Laboratorio de Bacteriología y Micología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Central del Ecuador, Quito, Pichincha, Ecuador
| | - José Luis Medina-Santana
- Unidad de Investigación de Enfermedades Transmitidas por Alimentos y Resistencia a los Antimicrobianos (UNIETAR). Facultad de Medicina Veterinaria y Zootecnia, Universidad Central del Ecuador, Quito, Pichincha, Ecuador
| | - María Cevallos-Almeida
- Laboratorio de Bacteriología y Micología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Central del Ecuador, Quito, Pichincha, Ecuador
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3
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Wu X, Suksawat F, Phuektes P, Siriwong S, Liu H, Li W, Angkititrakul S. Flagella Phenotypic Variations of ST34 Type Salmonella Typhimurium and Variants. Foodborne Pathog Dis 2024. [PMID: 38466980 DOI: 10.1089/fpd.2023.0091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/13/2024] Open
Abstract
Salmonella enterica serovar Typhimurium and its variants are the most common serotypes of human salmonellosis cases. Serotyping Salmonella Typhimurium and its variants has always been challenging. Our previous work found that among 14 Salmonella Typhimurium and variant strains, some different antigenic formulas had 100% pulsed-field gel electrophoresis (PFGE) similarity. The 14 strains were sorted into 3 groups; in each group, the different antigenic formulas had the same PFGE patterns. This phenomenon suggested that different antigenic formula identification might originate from a common ancestor subtyped by PFGE. To assess whether the serotyping method on Salmonella Typhimurium and variant strains reflected the genetic relationship, we improved the discrimination for the phylogenetic relationship among the 14 Salmonella Typhimurium and variant strains using Fourier-transform infrared spectroscopy (FTIR) and whole-genome multilocus sequence typing (wgMLST). We compared the wgMLST assay of 14 Salmonella Typhimurium and variant strains from this study with 50 public ST34 strain data of Salmonella Typhimurium and variant strains. We also compared flagella (H antigen)-related genes based on the whole genome of 14 strains and the other 293 ST34 public database for further understanding of this question. The phylogenetic results (PFGE) showed no regularity between the antigenic formulas and genotypes. The results of the higher discrimination power assays (FTIR and whole-genome multilocus sequence typing) also showed no regularity between the antigenic formulas and genotypes (or phenotypes). The 58 flagella encoding genes of different antigenic formulas were sorted into 13 patterns. However, a similar phenomenon was found: the same flagella encoding gene patterns could express different antigenic formulas. In conclusion, there is no consistency between the antigenic formulas and phylogenetic relationships among ST34 Salmonella Typhimurium and variant strains, even in flagella antigenic formula and flagella encoding genes.
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Affiliation(s)
- Xin Wu
- Yunnan Joint International R&D Center of Veterinary Public Health, College of Veterinary Medicine, Yunnan Agricultural University, Kunming, China
| | - Fanan Suksawat
- Faculty of Veterinary Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Patchara Phuektes
- Faculty of Veterinary Medicine, Khon Kaen University, Khon Kaen, Thailand
| | | | - Hongmei Liu
- Faculty of Veterinary Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Wengui Li
- Yunnan Joint International R&D Center of Veterinary Public Health, College of Veterinary Medicine, Yunnan Agricultural University, Kunming, China
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4
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Development and application of a multiplex PCR method to differentiate Salmonella enterica serovar Typhimurium from its monophasic variants in pig farms. Food Microbiol 2023; 109:104135. [DOI: 10.1016/j.fm.2022.104135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 09/01/2022] [Accepted: 09/05/2022] [Indexed: 11/19/2022]
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5
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Win AT, Supa-amornkul S, Orsi RH, Carey JH, Wolfgang WJ, Chaturongakul S. Sequence Analyses and Phenotypic Characterization Revealed Multidrug Resistant Gene Insertions in the Genomic Region Encompassing Phase 2 Flagellin Encoding fljAB Genes in Monophasic Variant Salmonella enterica Serovar 4,5,12:i:- Isolates From Various Sources in Thailand. Front Microbiol 2021; 12:720604. [PMID: 34675896 PMCID: PMC8524439 DOI: 10.3389/fmicb.2021.720604] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 09/13/2021] [Indexed: 11/13/2022] Open
Abstract
Salmonella enterica serovar 4,5,12:i:- (S. 4,5,12:i:-), a monophasic variant of Salmonella Typhimurium (STm) lacking the phase 2 flagellin encoding genes fljAB, has become increasingly prevalent worldwide. The increasing trends in multidrug resistant (MDR) S. 4,5,12:i:- prevalence also pose an important global health threat. Though many reports have characterized phenotypic and genotypic drug resistance of this serovar, few studies have characterized antimicrobial resistance of this serovar in Thailand. In this study, 108 S. 4,5,12:i:- isolates from various sources in Thailand and four international S. 4,5,12:i:- isolates were screened using polymerase chain reaction (PCR) to detect the presence of five target regions which are associated with antimicrobial resistant (AMR) genes, in the genomic region that contained fljAB genes in STm. We determined AMR phenotypes of all isolates by Kirby-Bauer disk diffusion method. Whole genome sequencing (WGS) was performed on 53 representative isolates (based on differences in the pulsed filed gel electrophoresis profiles, the sources of isolate, and the PCR and AMR patterns) to characterize the genetic basis of AMR phenotype and to identify the location of AMR determinants. Based on PCR screening, nine PCR profiles showing distinct deletion patterns of the five target regions have been observed. Approximately 76% of isolates (or 85 of 112 isolates), all of which were Thai isolates, contained five target regions inserted between STM2759 and iroB gene. A total of 21 phenotypic AMR patterns were identified with the predominant AmpST resistant phenotype [i.e., 84% (or 94 of 112) tested positive for resistance to ampicillin, streptomycin, and tetracycline], and 89% (or 100 of 112) were found to be MDR (defined here as resistant to at least three classes of tested antimicrobials). Using WGS data, a total of 24 genotypic AMR determinants belonging to seven different antimicrobial groups were found. AMR determinants (i.e., blaTEM - 1 , strB-A, sul2, and tetB, conferring resistance to ampicillin, streptomycin, sulfonamides, and tetracycline, respectively) were found to be inserted in a region typically occupied by the phase 2 flagellin encoding genes in STm. These resistant genes were flanked by a number of insertion sequences (IS), and co-localized with mercury tolerance genes. Our findings identify AMR genes, possibly associated with multiple IS26 copies, in the genetic region between STM2759 and iroB genes replacing phase 2 flagellin encoding fljAB genes in Thai S. 4,5,12:i:- isolates.
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Affiliation(s)
- Aye Thida Win
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Sirirak Supa-amornkul
- Mahidol International Dental School, Faculty of Dentistry, Mahidol University, Bangkok, Thailand
| | - Renato H. Orsi
- Department of Food Science, Cornell University, Ithaca, NY, United States
| | - Jaclyn H. Carey
- Bacteriology Laboratory, New York State Department of Health, Wadsworth Center, Albany, NY, United States
| | - William J. Wolfgang
- Bacteriology Laboratory, New York State Department of Health, Wadsworth Center, Albany, NY, United States
| | - Soraya Chaturongakul
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand
- Center of Microbial Genomics (CENMIG), Faculty of Science, Mahidol University, Bangkok, Thailand
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6
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Klubthawee N, Aunpad R. A Thermostable, Modified Cathelicidin-Derived Peptide With Enhanced Membrane-Active Activity Against Salmonella enterica serovar Typhimurium. Front Microbiol 2021; 11:592220. [PMID: 33519729 PMCID: PMC7838546 DOI: 10.3389/fmicb.2020.592220] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 12/16/2020] [Indexed: 02/05/2023] Open
Abstract
Foodborne illness caused by consumption of food contaminated with Salmonella is one of the most common causes of diarrheal disease and affects millions of people worldwide. The rising emergence and spread of antimicrobial resistance, especially in some serotypes of Salmonella, has raised a great awareness of public health issues worldwide. To ensure safety of the food processing chain, the development of new food preservatives must be expedited. Recently, thermal- and pH-stable antimicrobial peptides have received much attention for use in food production, and represent safe alternatives to chemical preservatives. A 12-mer cathelicidin-derived, α-helical cationic peptide, P7, displayed rapid killing activity, against strains of drug-resistant foodborne Salmonella enterica serovar Typhimurium and its monophasic variant (S. enterica serovar 4,5,12:i:-) and had minimal toxicity against mouse fibroblast cells. P7 tended to form helical structure in the membrane-mimic environments as evaluated by circular dichroism (CD) spectroscopy. The action mode of P7 at the membrane-level was affirmed by the results of flow cytometry, and confocal, scanning and transmission electron microscopy. P7 killed bacteria through binding to bacterial membranes, penetration and the subsequent accumulation in S. enterica serovar Typhimurium cytoplasm. This induced membrane depolarization, permeabilization, and sequential leakage of intracellular substances and cell death. Except for sensitivity to proteolytic digestive enzymes, P7 maintained its inhibitory activity against S. enterica serovar Typhimurium in the presence of different conditions [various salts, extreme pHs and heat (even at 100°C)]. Moreover, the peptide is unlikely to induce bacterial resistance in vitro. Taken together, this study demonstrated that the membrane-permeabilizing P7 peptide has much potential as a new antimicrobial agent for use in food processing and preservation.
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Affiliation(s)
- Natthaporn Klubthawee
- Graduate Program in Biomedical Sciences, Faculty of Allied Health Sciences, Thammasat University, Pathum Thani, Thailand
| | - Ratchaneewan Aunpad
- Graduate Program in Biomedical Sciences, Faculty of Allied Health Sciences, Thammasat University, Pathum Thani, Thailand
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7
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Genotyping Study of Salmonella 4,[5],12:i:- Monophasic Variant of Serovar Typhimurium and Characterization of the Second-Phase Flagellar Deletion by Whole Genome Sequencing. Microorganisms 2020; 8:microorganisms8122049. [PMID: 33371352 PMCID: PMC7767384 DOI: 10.3390/microorganisms8122049] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 12/17/2020] [Accepted: 12/17/2020] [Indexed: 11/23/2022] Open
Abstract
After Salmonella Enteritidis and S. Typhimurium, S. 4,[5],12:i:- is the most reported serovar in human clinical cases. During the past 20 years, many tools have been used for its typing and second-phase flagellar deletion characterization. Currently, whole genome sequencing (WGS) and different bioinformatic programs have shown the potential to be more accurate than earlier tools. To assess this potential, we analyzed by WGS and in silico typing a selection of 42 isolates of S. 4,[5],12:i:- and S. Typhimurium with different in vitro characteristics. Comparative analysis showed that SeqSero2 does not differentiate fljB-positive S. 4,[5],12:i:- strains from those of serovar Typhimurium. Our results proved that the strains selected for this work were non-clonal S. 4,[5],12:i:- strains circulating in Spain. Using WGS data, we identified 13 different deletion types of the second-phase flagellar genomic region. Most of the deletions were generated by IS26 insertions, showing orientation-dependent conserved deletion ends. In addition, we detected S. 4,[5],12:i:- strains of the American clonal line that would give rise to the Southern European clone in Spain. Our results suggest that new S. 4,[5],12:i:- strains are continuously emerging from different S. Typhimurium strains via different genetic events, at least in swine products.
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8
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Elbediwi M, Beibei W, Pan H, Jiang Z, Biswas S, Li Y, Yue M. Genomic Characterization of mcr-1-carrying Salmonella enterica Serovar 4,[5],12:i:- ST 34 Clone Isolated From Pigs in China. Front Bioeng Biotechnol 2020; 8:663. [PMID: 32714906 PMCID: PMC7344297 DOI: 10.3389/fbioe.2020.00663] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 05/28/2020] [Indexed: 12/31/2022] Open
Abstract
Salmonella enterica serovar 4,[5],12:i:-, so-called Typhimurium monophasic variant, has become one of the most frequently isolated serovars both in humans and in animals all over the world. The increasing prevalence of mcr-1-carrying Salmonella poses significant global health concerns. However, the potential role of Salmonella 4,[5],12:i:- in mcr-1 gene migration through the food chain to the human remains obscure. Here, we investigated 337 Salmonella isolates from apparently healthy finishing pigs, which is rarely studied, obtained from pig farms and slaughterhouses in China. The mcr-1 gene was found in four colistin-resistant S. enterica 4,[5],12:i:- isolates. Notably, all four isolates belonged to sequence type 34 (ST34) with multidrug resistance phenotype. Further genomic sequencing and antimicrobial resistance characterization confirmed that mcr was responsible for the colistin resistance, and the conjugation assay demonstrated that three of four isolates carried mcr-1 in IncHI2 plasmid. Importantly, mcr-1 and class-1 integron were found to co-localize in two strains with IncHI2 plasmid. By collecting all the mcr-1-carrying Typhimurium and monophasic variant strains across the food chain (farm animals, animal-origin food, and humans), our phylogenomic analysis of available 66 genomes, including four strains in this study, demonstrated an independent phylogenetic cluster of all eight Chinese swine-originated isolates and one human isolate. Together, this study provides direct evidence for clonal and pork-borne transmission of mcr-1 by Salmonella 4,[5],12:i:- ST34 in China and highlighted a domestication pathway by acquisition of additional antimicrobial resistance determinants in Chinese ST34 isolates.
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Affiliation(s)
- Mohammed Elbediwi
- Institute of Preventive Veterinary Sciences, Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Wu Beibei
- Zhejiang Province Center for Disease Control and Prevention, Hangzhou, China
| | - Hang Pan
- Institute of Preventive Veterinary Sciences, Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Zenghai Jiang
- College of Veterinary Medicine, Henan University of Animal Husbandry and Economy, Zhengzhou, China
| | - Silpak Biswas
- Institute of Preventive Veterinary Sciences, Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Yan Li
- Institute of Preventive Veterinary Sciences, Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Min Yue
- Institute of Preventive Veterinary Sciences, Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China.,Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China
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9
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Naberhaus SA, Krull AC, Arruda BL, Arruda P, Sahin O, Schwartz KJ, Burrough ER, Magstadt DR, Matias Ferreyra F, Gatto IRH, Meiroz de Souza Almeida H, Wang C, Kreuder AJ. Pathogenicity and Competitive Fitness of Salmonella enterica Serovar 4,[5],12:i:- Compared to Salmonella Typhimurium and Salmonella Derby in Swine. Front Vet Sci 2020; 6:502. [PMID: 32083096 PMCID: PMC7002397 DOI: 10.3389/fvets.2019.00502] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 12/19/2019] [Indexed: 12/14/2022] Open
Abstract
Since 2014, Salmonella 4,[5],12:i:- has emerged as the most common serovar of Salmonella enterica identified from swine samples submitted to veterinary diagnostic laboratories in the United States. To compare the pathogenicity of S. 4,[5],12:i:- in swine to the known pathogenic Salmonella Typhimurium and lesser pathogenic Salmonella Derby, 72 pigs (20 per Salmonella serovar treatment and 12 controls) were inoculated with either S. Typhimurium, S. 4,[5],12:i:-, S. Derby, or sham-inoculated and followed for up to 28 days thereafter via rectal temperature, fecal scoring, and fecal culture. Animals were euthanized on days 2, 4, or 28 to determine the gross and histopathologic signs of disease and tissue colonization. The results clearly demonstrate that for the isolates selected, serovar 4,[5],12:i:- possesses similar ability as serovar Typhimurium to cause clinical disease, colonize the tonsils and ileocecal lymph nodes, and be shed in the feces of infected swine past resolution of clinical disease. To compare the competitive fitness of S. 4,[5],12:i:- to S. Typhimurium in swine when co-infected, 12 pigs were co-inoculated with equal concentrations of both S. Typhimurium and S. 4,[5],12:i and followed for up to 10 days thereafter. When co-inoculated, serovar 4,[5],12:i:- was consistently detected in the feces of a higher percentage of pigs and at higher concentrations than serovar Typhimurium, suggesting an increased competitive fitness of 4,[5],12:i:- relative to serovar Typhimurium when inoculated simultaneously into naïve pigs. Whole genome sequencing analysis of the isolates used in these studies revealed similar virulence factor presence in all S. 4,[5],12:i:- and S. Typhimurium isolates, but not S. Derby, providing additional evidence for similar pathogenicity potential between serovars 4,[5],12:i:- and Typhimurium. Altogether, this data strongly supports the hypothesis that S. 4,[5],12:i:- is a pathogen of swine and suggests a mechanism through increased competitive fitness for the increasing identification of Salmonella 4,[5],12:i:- in swine diagnostic samples over the past several years.
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Affiliation(s)
- Samantha A Naberhaus
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Adam C Krull
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Bailey L Arruda
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Paulo Arruda
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Orhan Sahin
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Kent J Schwartz
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Eric R Burrough
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Drew R Magstadt
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Franco Matias Ferreyra
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Igor R H Gatto
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Henrique Meiroz de Souza Almeida
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
| | - Chong Wang
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States.,Department of Statistics, College of Liberal Arts and Sciences, Iowa State University, Ames, IA, United States
| | - Amanda J Kreuder
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States.,Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States
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10
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Diep B, Barretto C, Portmann AC, Fournier C, Karczmarek A, Voets G, Li S, Deng X, Klijn A. Salmonella Serotyping; Comparison of the Traditional Method to a Microarray-Based Method and an in silico Platform Using Whole Genome Sequencing Data. Front Microbiol 2019; 10:2554. [PMID: 31781065 PMCID: PMC6859910 DOI: 10.3389/fmicb.2019.02554] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 10/22/2019] [Indexed: 11/13/2022] Open
Abstract
Salmonella is one of the most common causes of food-borne diseases worldwide. While Salmonella molecular subtyping by Whole Genome Sequencing (WGS) is increasingly used for outbreak and source tracking investigations, serotyping remains as a first-line characterization of Salmonella isolates. The traditional phenotypic method for serotyping is logistically challenging, as it requires the use of more than 150 specific antisera and well trained personnel to interpret the results. Consequently, it is not a routine method for the majority of laboratories. Several rapid molecular methods targeting O and H loci or surrogate genomic markers have been developed as alternative solutions. With the expansion of WGS, in silico Salmonella serotype prediction using WGS data is available. Here, we compared a microarray method using molecular markers, the Check and Trace Salmonella assay (CTS) and a WGS-based serotype prediction tool that targets molecular determinants of serotype (SeqSero) to the traditional phenotypic method using 100 strains representing 45 common and uncommon serotypes. Compared to the traditional method, the CTS assay correctly serotyped 97% of the strains, four strains gave a double serotype prediction. Among the inconclusive data, one strain was not predicted and two strains were incorrectly identified. SeqSero was evaluated with two versions (SeqSero 1 and the alpha test version of SeqSero 2). The correct antigenic formula was predicted by SeqSero 1 for 96 and 95% of strains using raw reads and assembly, respectively. However, 34 and 33% of these predictions included multiple serotypes by raw reads and assembly. With raw reads, one strain was not identified and three strains were discordant with phenotypic serotyping result. With assembly, three strains were not predicted and two strains were incorrectly predicted. While still under development, SeqSero 2 maintained the accuracy of antigenic formula prediction at 98% and reduced multiple serotype prediction rate to 13%. One strain had no prediction and one strain was incorrectly predicted. Our study indicates that the CTS assay is a good alternative for routine laboratories as it is an easy to use method with a short turn-around-time. SeqSero is a reliable replacement for phenotypic serotyping if WGS is routinely implemented.
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Affiliation(s)
| | | | | | | | | | | | - Shaoting Li
- Center for Food Safety, University of Georgia, Athens, GA, United States
| | - Xiangyu Deng
- Center for Food Safety, University of Georgia, Athens, GA, United States
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11
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Naberhaus SA, Krull AC, Bradner LK, Harmon KM, Arruda P, Arruda BL, Sahin O, Burrough ER, Schwartz KJ, Kreuder AJ. Emergence of Salmonella enterica serovar 4,[5],12:i:- as the primary serovar identified from swine clinical samples and development of a multiplex real-time PCR for improved Salmonella serovar-level identification. J Vet Diagn Invest 2019; 31:818-827. [PMID: 31646949 DOI: 10.1177/1040638719883843] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Rapid identification of the infecting Salmonella serovar from porcine diagnostic samples is vital to allow implementation of appropriate on-farm treatment and management decisions. Although identification at the serogroup level can be rapidly achieved at most veterinary diagnostic laboratories, final Salmonella serovar identification often takes several weeks because of the limited number of reference laboratories performing the complex task of serotyping. Salmonella serogroup B, currently the dominant serogroup identified from swine clinical samples in the United States, contains serovars that vary from highly pathogenic to minimally pathogenic in swine. We determined the frequency of detection of individual group B serovars at the Iowa State Veterinary Diagnostic Laboratory from 2008 to 2017, and validated a multiplex real-time PCR (rtPCR) to distinguish pathogenic serogroup B serovars from those of lesser pathogenicity. Our results indicate that, since 2014, Salmonella enterica ssp. enterica serovar 4,[5],12:i:- has been the dominant serovar identified from swine clinical samples at the ISU-VDL, with S. Typhimurium now the second most common serovar identified. We developed a rtPCR to allow rapid differentiation of samples containing S. 4,[5],12:i:- and S. Typhimurium from samples containing serovars believed to be of less pathogenicity, such as S. Agona and S. Derby. When combined with enrichment culture, this rtPCR has the ability to significantly improve the time to final serovar identification of the 2 most commonly identified pathogenic Salmonella serovars in swine, and allows rapid implementation of serovar-specific intervention strategies.
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Affiliation(s)
- Samantha A Naberhaus
- Departments of Veterinary Diagnostic and Production Animal Medicine (Naberhaus, Krull, Bradner, Harmon, P. Arruda, B. Arruda, Sahin, Burrough, Schwartz, Kreuder), Iowa State University, Ames, IA.,Veterinary Microbiology and Preventive Medicine (Naberhaus, Kreuder), Iowa State University, Ames, IA
| | - Adam C Krull
- Departments of Veterinary Diagnostic and Production Animal Medicine (Naberhaus, Krull, Bradner, Harmon, P. Arruda, B. Arruda, Sahin, Burrough, Schwartz, Kreuder), Iowa State University, Ames, IA.,Veterinary Microbiology and Preventive Medicine (Naberhaus, Kreuder), Iowa State University, Ames, IA
| | - Laura K Bradner
- Departments of Veterinary Diagnostic and Production Animal Medicine (Naberhaus, Krull, Bradner, Harmon, P. Arruda, B. Arruda, Sahin, Burrough, Schwartz, Kreuder), Iowa State University, Ames, IA.,Veterinary Microbiology and Preventive Medicine (Naberhaus, Kreuder), Iowa State University, Ames, IA
| | - Karen M Harmon
- Departments of Veterinary Diagnostic and Production Animal Medicine (Naberhaus, Krull, Bradner, Harmon, P. Arruda, B. Arruda, Sahin, Burrough, Schwartz, Kreuder), Iowa State University, Ames, IA.,Veterinary Microbiology and Preventive Medicine (Naberhaus, Kreuder), Iowa State University, Ames, IA
| | - Paulo Arruda
- Departments of Veterinary Diagnostic and Production Animal Medicine (Naberhaus, Krull, Bradner, Harmon, P. Arruda, B. Arruda, Sahin, Burrough, Schwartz, Kreuder), Iowa State University, Ames, IA.,Veterinary Microbiology and Preventive Medicine (Naberhaus, Kreuder), Iowa State University, Ames, IA
| | - Bailey L Arruda
- Departments of Veterinary Diagnostic and Production Animal Medicine (Naberhaus, Krull, Bradner, Harmon, P. Arruda, B. Arruda, Sahin, Burrough, Schwartz, Kreuder), Iowa State University, Ames, IA.,Veterinary Microbiology and Preventive Medicine (Naberhaus, Kreuder), Iowa State University, Ames, IA
| | - Orhan Sahin
- Departments of Veterinary Diagnostic and Production Animal Medicine (Naberhaus, Krull, Bradner, Harmon, P. Arruda, B. Arruda, Sahin, Burrough, Schwartz, Kreuder), Iowa State University, Ames, IA.,Veterinary Microbiology and Preventive Medicine (Naberhaus, Kreuder), Iowa State University, Ames, IA
| | - Eric R Burrough
- Departments of Veterinary Diagnostic and Production Animal Medicine (Naberhaus, Krull, Bradner, Harmon, P. Arruda, B. Arruda, Sahin, Burrough, Schwartz, Kreuder), Iowa State University, Ames, IA.,Veterinary Microbiology and Preventive Medicine (Naberhaus, Kreuder), Iowa State University, Ames, IA
| | - Kent J Schwartz
- Departments of Veterinary Diagnostic and Production Animal Medicine (Naberhaus, Krull, Bradner, Harmon, P. Arruda, B. Arruda, Sahin, Burrough, Schwartz, Kreuder), Iowa State University, Ames, IA.,Veterinary Microbiology and Preventive Medicine (Naberhaus, Kreuder), Iowa State University, Ames, IA
| | - Amanda J Kreuder
- Departments of Veterinary Diagnostic and Production Animal Medicine (Naberhaus, Krull, Bradner, Harmon, P. Arruda, B. Arruda, Sahin, Burrough, Schwartz, Kreuder), Iowa State University, Ames, IA.,Veterinary Microbiology and Preventive Medicine (Naberhaus, Kreuder), Iowa State University, Ames, IA
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12
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Sun H, Wan Y, Du P, Bai L. The Epidemiology of Monophasic Salmonella Typhimurium. Foodborne Pathog Dis 2019; 17:87-97. [PMID: 31532231 DOI: 10.1089/fpd.2019.2676] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Salmonella enterica remains an important foodborne pathogen in all regions of the world, with Typhimurium as one of the most frequent serotypes causing foodborne disease. However, the past two decades have seen a rapid worldwide emergence of a new Salmonella serotype, namely monophasic variant of S. Typhimurium, whose antigenic formula is 1,4,[5],12:i:-. It has become one of the 2-5 most common Salmonella serotypes responsible for animal and human infections in different regions. The global epidemic of monophasic S. 1,4,[5],12:i:- has mainly been characterized by an increase in multidrug-resistant S. 1,4,[5],12:i:- isolated in Europe since 1997. The unexpected link to swine has escalated monophasic S. Typhimurium infections to the status of a global public health emergency. The large-scale application of whole genome sequencing (WGS) in the last 10 years has revealed the phylogenetic associations of the bacterium and its antimicrobial resistance (AMR) genes. Local and global transmission reconstructed by WGS have shown that different clones have emerged following multiple independent events worldwide, and have elucidated the role of this zoonotic pathogen in the spread of AMR. This article discusses our current knowledge of the global ecology, epidemiology, transmission, bacterial adaptation, and evolution of this emerging Salmonella serotype.
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Affiliation(s)
- Honghu Sun
- Key Laboratory of Food Safety Risk Assessment, National Health Commission of the People's Republic of China, China National Center for Food Safety Risk Assessment, Beijing, China.,Chengdu Institute for Food and Drug Control, Chengdu, China
| | - Yuping Wan
- Chengdu Institute for Food and Drug Control, Chengdu, China
| | - Pengcheng Du
- Beijing Key Laboratory of Emerging Infectious Diseases, Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing, China
| | - Li Bai
- Key Laboratory of Food Safety Risk Assessment, National Health Commission of the People's Republic of China, China National Center for Food Safety Risk Assessment, Beijing, China
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13
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Khaltabadi RF, Shahrokhi N, Ebrahimi-Rad M, Ehsani P. Salmonella Typhimurium in Iran: Contribution of molecular and IS200 PCR methods in variants detection. PLoS One 2019; 14:e0213726. [PMID: 30865712 PMCID: PMC6415898 DOI: 10.1371/journal.pone.0213726] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 02/27/2019] [Indexed: 11/23/2022] Open
Abstract
Salmonella Typhimurium, a zoonotic pathogen, is regarded as a major health and economic concern worldwide. Recently, monophasic variants of this serovar have been significantly associated with human gastroenteritis outbreaks globally, making its accurate identification essential for epidemiological and control purposes. We have identified and analyzed 150 S. Typhimurium from 884 Salmonella genus isolated from humans, domestic animals, poultry, food items and abattoirs origins. The Salmonella isolates were obtained from Iranian National Veterinary Reference Laboratories of 9 provinces during 2007–2016, and from five hospitals in Tehran in 2015. The isolates were evaluated biochemically, serologically, and by PCR amplification of invA, mdh, STM4492, fliC, fljA, fljB, hin genes, IS200 and DT104. invA and mdh genes were used to confirm the S. Typhimurium serotype, fliC and fljB genes for determination of monophasic variants and amplification of IS200 to discriminate the monophasic variants from the closely related serotypes. We identified 78.6% (118/150) as classical S. Typhimurium (fliC, fljB and IS200 positive), 12.6% (19/150) were IS200 negative from all isolates. DT104 is another marker for S.Typhimurium serovar typing. Contrary to EFSA guidelines 20.6% (19/29) of human isolates that lacked IS200 insertion sequence, were confirmed as S.Typhimurium. Compared to the North American/European isolates the low prevalence of fljB negative 6% (9/150) and the high abundance of fliC negative 23.3% (35/150) isolates also were indicative of a different regional atypical population. Studies have shown that the prevalence of monophasic (fljB-) S. Typhimurium worldwide is promoted by the Swine industry. Thus, one reason for this high number of different atypical strains could be inhibition of swine breeding system (house hold and industry) in Iran. These results demonstrate a need for a modified identifying protocol to overcome the regional differences.
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Affiliation(s)
- Reza Farahani Khaltabadi
- Department of Molecular Biology, Pasteur Institute of Iran, Tehran, Iran
- Department of Molecular Biology, National Veterinary Reference Laboratory, Iranian Veterinary Organization, Tehran, Iran
| | - Nader Shahrokhi
- Department of Molecular Biology, National Veterinary Reference Laboratory, Iranian Veterinary Organization, Tehran, Iran
| | | | - Parastoo Ehsani
- Department of Molecular Biology, Pasteur Institute of Iran, Tehran, Iran
- * E-mail:
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14
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Cevallos-Almeida M, Martin L, Houdayer C, Rose V, Guionnet JM, Paboeuf F, Denis M, Kerouanton A. Experimental infection of pigs by Salmonella Derby, S. Typhimurium and monophasic variant of S. Typhimurium: Comparison of colonization and serology. Vet Microbiol 2019; 231:147-153. [PMID: 30955802 DOI: 10.1016/j.vetmic.2019.03.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 03/01/2019] [Accepted: 03/03/2019] [Indexed: 11/25/2022]
Abstract
Salmonella serovars Derby, Typhimurium and the monophasic variant of Salmonella Typhimurium are the most frequently isolated serovars in pigs in France. To compare the excretion patterns, seroconversion to Salmonella and contamination of the organs of pigs inoculated with strains of all three serovars, we conducted an experimental trial with 28 SPF piglets. Four were used as a negative control, while the other 24 were divided equally into three groups. Each group was inoculated at 7 weeks of age with a different strain: S. Derby (SDb), S. Typhimurium (ST), and the monophasic variant of S. Typhimurium (mST). Fecal and blood samples were collected twice a week up until necropsy, on 21 days post-inoculation (DPI) for half of each group and 49 DPI for the remaining piglets. During necropsy, the tonsils, mesenteric lymph nodes and various intestinal contents were collected from each pig. Salmonella bacteria were quantified in CFU/g by a bacteriological method, and levels of Salmonella antibodies were measured using an ELISA Kit. Piglets inoculated with mST continuously excreted Salmonella in their feces throughout the trial. For each of the other serovars, one piglet was Salmonella-negative on one DPI. The quantity of Salmonella excreted was statistically different between the group inoculated with ST and mST (p < 0.05), but no differences were found between the other serovars. The tonsils, cecum and jejunum were the most contaminated organs in all groups. Seroconversion for all the piglets was completed by different DPI: 28 for ST, 31 for mST and 38 for SDb. No major differences were found in terms of excretion and colonization among the studied serovars.
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Affiliation(s)
- María Cevallos-Almeida
- ANSES, Hygiene and Quality of Poultry and Pig Products Unit, BP 53, 22440 Ploufragan, France; Faculty of Veterinary Medicine and Zootechnics, Central University of Ecuador, Quito, Ecuador
| | - Laure Martin
- ANSES, Hygiene and Quality of Poultry and Pig Products Unit, BP 53, 22440 Ploufragan, France
| | - Catherine Houdayer
- ANSES, Hygiene and Quality of Poultry and Pig Products Unit, BP 53, 22440 Ploufragan, France
| | - Valerie Rose
- ANSES, Hygiene and Quality of Poultry and Pig Products Unit, BP 53, 22440 Ploufragan, France
| | - Jean-Marie Guionnet
- ANSES, SPF Pig Production and Experimental Unit, BP 53, 22440 Ploufragan, France
| | - Frédéric Paboeuf
- ANSES, SPF Pig Production and Experimental Unit, BP 53, 22440 Ploufragan, France
| | - Martine Denis
- ANSES, Hygiene and Quality of Poultry and Pig Products Unit, BP 53, 22440 Ploufragan, France
| | - Annaëlle Kerouanton
- ANSES, Hygiene and Quality of Poultry and Pig Products Unit, BP 53, 22440 Ploufragan, France.
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15
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Mastrorilli E, Pietrucci D, Barco L, Ammendola S, Petrin S, Longo A, Mantovani C, Battistoni A, Ricci A, Desideri A, Losasso C. A Comparative Genomic Analysis Provides Novel Insights Into the Ecological Success of the Monophasic Salmonella Serovar 4,[5],12:i:. Front Microbiol 2018; 9:715. [PMID: 29719530 PMCID: PMC5913373 DOI: 10.3389/fmicb.2018.00715] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 03/27/2018] [Indexed: 12/27/2022] Open
Abstract
Over the past decades, Salmonella 4,[5],12:i:- has rapidly emerged and it is isolated with high frequency in the swine food chain. Although many studies have documented the epidemiological success of this serovar, few investigations have tried to explain this phenomenon from a genetic perspective. Here a comparative whole-genome analysis of 50 epidemiologically unrelated S. 4,[5],12:i:-, isolated in Italy from 2010 to 2016 was performed, characterizing them in terms of genetic elements potentially conferring resistance, tolerance and persistence characteristics. Phylogenetic analyses indicated interesting distinctions among the investigated isolates. The most striking genetic trait characterizing the analyzed isolates is the widespread presence of heavy metals tolerance gene cassettes: most of the strains possess genes expected to confer resistance to copper and silver, whereas about half of the isolates also contain the mercury tolerance gene merA. A functional assay showed that these genes might be useful for preventing the toxic effects of metals, thus supporting the hypothesis that they can contribute to the success of S. 4,[5],12:i:- in farming environments. In addition, the analysis of the distribution of type II toxin-antitoxin families indicated that these elements are abundant in this serovar, suggesting that this is another factor that might favor its successful spread.
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Affiliation(s)
- Eleonora Mastrorilli
- Department of Food Safety, National Reference Center for Salmonella, Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Italy
| | | | - Lisa Barco
- Department of Food Safety, National Reference Center for Salmonella, Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Italy
| | - Serena Ammendola
- Department of Biology, University of Rome Tor Vergata, Rome, Italy
| | - Sara Petrin
- Department of Food Safety, National Reference Center for Salmonella, Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Italy
| | - Alessandra Longo
- Department of Food Safety, National Reference Center for Salmonella, Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Italy
| | - Claudio Mantovani
- Science Communication Laboratory, Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Italy
| | | | - Antonia Ricci
- Department of Food Safety, National Reference Center for Salmonella, Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Italy
| | | | - Carmen Losasso
- Department of Food Safety, National Reference Center for Salmonella, Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Italy
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16
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Felten A, Guillier L, Radomski N, Mistou MY, Lailler R, Cadel-Six S. Genome Target Evaluator (GTEvaluator): A workflow exploiting genome dataset to measure the sensitivity and specificity of genetic markers. PLoS One 2017; 12:e0182082. [PMID: 28750049 PMCID: PMC5531552 DOI: 10.1371/journal.pone.0182082] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 07/12/2017] [Indexed: 11/30/2022] Open
Abstract
Most of the bacterial typing methods used to discriminate isolates in medical or food safety microbiology are based on genetic markers used as targets in PCR or hybridization experiments. These DNA typing methods are important tools for studying prevalence and epidemiology, for conducting surveillance, investigations and control of biological hazard sources. In that perspective, it is crucial to insure that the chosen genetic markers have the greatest specificity and sensitivity. The wealth of whole-genome sequences available for many bacterial species offers the opportunity to evaluate the performance of these genetic markers. In the present study, we have developed GTEvaluator, a bioinformatics workflow which ranks genetic markers depending on their sensitivity and specificity towards groups of well-defined genomes. GTEvaluator identifies the most performant genetic markers to target individuals among a population. The individuals (i.e. a group of genomes within a collection) are defined by any kind of particular phenotypic or biological properties inside a related population (i.e. collection of genomes). The performance of the genetic markers is computed by a distance value which takes into account both sensitivity and specificity. In this study we report two examples of GTEvaluator application. In the first example Bacillus phenotypic markers were evaluated for their capacity to distinguish B. cereus from B. thuringiensis. In the second experiment, GTEvaluator measured the performance of genetic markers dedicated to the molecular serotyping of Salmonella enterica. In one in silico experiment it was possible to test 64 markers onto 134 genomes corresponding to 14 different serotypes.
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Affiliation(s)
- Arnaud Felten
- Université PARIS-EST, ANSES, Laboratory for Food Safety, Maisons-Alfort, France
| | - Laurent Guillier
- Université PARIS-EST, ANSES, Laboratory for Food Safety, Maisons-Alfort, France
| | - Nicolas Radomski
- Université PARIS-EST, ANSES, Laboratory for Food Safety, Maisons-Alfort, France
| | - Michel-Yves Mistou
- Université PARIS-EST, ANSES, Laboratory for Food Safety, Maisons-Alfort, France
| | - Renaud Lailler
- Université PARIS-EST, ANSES, Laboratory for Food Safety, Maisons-Alfort, France
| | - Sabrina Cadel-Six
- Université PARIS-EST, ANSES, Laboratory for Food Safety, Maisons-Alfort, France
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17
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Boland C, Van Hessche M, Mahillon J, Wattiau P. A liquid bead array for the identification and characterization of fljB-positive and fljB-negative monophasic variants of Salmonella Typhimurium. Food Microbiol 2017; 71:17-24. [PMID: 29366463 DOI: 10.1016/j.fm.2017.04.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 03/31/2017] [Accepted: 04/09/2017] [Indexed: 12/13/2022]
Abstract
Salmonella1,4,[5],12:i:- accounts currently for one of the most common serotypes observed worldwide. These isolates do not express the FljB flagellin and mostly derive from Salmonella Typhimurium. They are therefore termed Salmonella Typhimurium monophasic variants (STMV) and are considered of comparable public health risk. Since serological identification of the somatic and flagellar antigens of STMV is not sufficient to demonstrate relatedness with Salmonella Typhimurium, additional assays detecting genetic markers unique to Salmonella Typhimurium are required. In addition, identification of the mutations affecting expression of the flagellar gene fljB can be useful to support the monophasic character observed phenotypically. Finally, genetic subtyping of the various mono- and biphasic Salmonella Typhimurium clonal groups can facilitate their epidemiological follow-up. Here, we present a home-made liquid bead array able to fulfill these requirements. This array confirmed the monophasic character of 240 STMV isolates collected in Belgium during 2014-2015 and identified 10 genetic subtypes. Microevolution in and around the fljB locus linked to IS26 insertions is probably one of the driven force accounting for STMV population diversity. Thanks to its open design, other genetic signatures could later be merged to the assay to subtype additional STMV clonal groups and to detect rare mutations.
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Affiliation(s)
- Cécile Boland
- Veterinary and Agrochemical Research Centre (CODA-CERVA), Operational Direction Bacterial Diseases, Foodborne Bacterial Zoonoses & Antibiotic Resistance Unit, Groeselenbergstr. 99, B-1180 Brussels, Belgium; Université catholique de Louvain (UCL), Faculty of Bioscience Engineering, Earth and Life Institute, Applied Microbiology Cluster (ELIM), Laboratory of Food and Environmental Microbiology, Croix du Sud, 2 - L7.05.12, 1348 Louvain-la-Neuve, Belgium.
| | - Mieke Van Hessche
- Veterinary and Agrochemical Research Centre (CODA-CERVA), Operational Direction Bacterial Diseases, Foodborne Bacterial Zoonoses & Antibiotic Resistance Unit, Groeselenbergstr. 99, B-1180 Brussels, Belgium.
| | - Jacques Mahillon
- Université catholique de Louvain (UCL), Faculty of Bioscience Engineering, Earth and Life Institute, Applied Microbiology Cluster (ELIM), Laboratory of Food and Environmental Microbiology, Croix du Sud, 2 - L7.05.12, 1348 Louvain-la-Neuve, Belgium.
| | - Pierre Wattiau
- Veterinary and Agrochemical Research Centre (CODA-CERVA), Operational Direction Bacterial Diseases, Foodborne Bacterial Zoonoses & Antibiotic Resistance Unit, Groeselenbergstr. 99, B-1180 Brussels, Belgium.
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18
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Trinh JT, Székely T, Shao Q, Balázsi G, Zeng L. Cell fate decisions emerge as phages cooperate or compete inside their host. Nat Commun 2017; 8:14341. [PMID: 28165024 PMCID: PMC5303824 DOI: 10.1038/ncomms14341] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 12/19/2016] [Indexed: 01/02/2023] Open
Abstract
The system of the bacterium Escherichia coli and its virus, bacteriophage lambda, is paradigmatic for gene regulation in cell-fate development, yet insight about its mechanisms and complexities are limited due to insufficient resolution of study. Here we develop a 4-colour fluorescence reporter system at the single-virus level, combined with computational models to unravel both the interactions between phages and how individual phages determine cellular fates. We find that phages cooperate during lysogenization, compete among each other during lysis, and that confusion between the two pathways occasionally occurs. Additionally, we observe that phage DNAs have fluctuating cellular arrival times and vie for resources to replicate, enabling the interplay during different developmental paths, where each phage genome may make an individual decision. These varied strategies could separate the selection for replication-optimizing beneficial mutations during lysis from sequence diversification during lysogeny, allowing rapid adaptation of phage populations for various environments.
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Affiliation(s)
- Jimmy T. Trinh
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843, USA
- Center for Phage Technology, Texas A&M University, College Station, Texas 77843, USA
| | - Tamás Székely
- The Louis and Beatrice Laufer Center for Physical and Quantitative Biology, Stony Brook University, Stony Brook, New York 11794, USA
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, New York 11794, USA
| | - Qiuyan Shao
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843, USA
- Center for Phage Technology, Texas A&M University, College Station, Texas 77843, USA
| | - Gábor Balázsi
- The Louis and Beatrice Laufer Center for Physical and Quantitative Biology, Stony Brook University, Stony Brook, New York 11794, USA
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, New York 11794, USA
| | - Lanying Zeng
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843, USA
- Center for Phage Technology, Texas A&M University, College Station, Texas 77843, USA
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19
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Multidrug-resistantSalmonella entericaSerovar Typhimurium Monophasic Variant 4,12:i:- Isolated from Asymptomatic Wildlife in a Catalonian Wildlife Rehabilitation Center, Spain. J Wildl Dis 2015; 51:759-63. [DOI: 10.7589/2015-01-019] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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20
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Extensive genetic variability linked to IS26 insertions in the fljB promoter region of atypical monophasic variants of Salmonella enterica serovar Typhimurium. Appl Environ Microbiol 2015; 81:3169-75. [PMID: 25724958 DOI: 10.1128/aem.00270-15] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 02/20/2015] [Indexed: 11/20/2022] Open
Abstract
Fifty-nine monophasic Salmonella enterica serovar Typhimurium isolates, collected in Belgium during the period from 2008 to 2011, have been serotyped as 4,[5]:i:- and shown to harbor an fljB coding sequence. The genetic differences between these strains and phenotypically biphasic Salmonella Typhimurium were analyzed through PCR and DNA sequencing. Genetic alterations in the fljB promoter region affecting expression of the phase 2 flagellin were observed in 53 isolates. Other genetic events in the invertible region carrying the fljB promoter were observed in 2 isolates. For the remaining 4 isolates, no molecular differences with a reference biphasic Salmonella Typhimurium strain could be observed. Next-generation sequencing of one representative isolate affected in the fljB promoter region revealed a 26-kb IS26 composite transposon insertion along with a local genomic rearrangement. Several other IS26 element-mediated alterations of this genomic region were observed. This group of monophasic Salmonella Typhimurium isolates was genetically heterogeneous, as revealed by multilocus variable-number tandem-repeat analysis (MLVA), PCR, and sequencing. Pigs and pork represented a major source of such monophasic isolates in Belgium, as reported in other countries. Three out of 5 isolates of human origin presented genetic profiles identical to those of food isolates, demonstrating the pathogenic potential of the newly characterized variants and potential dissemination along the food chain. This study highlighted the key role played by IS26 insertions in the loss of phase 2 flagellin expression and the subsequent generation of multiple monophasic variant lineages from biphasic Salmonella Typhimurium ancestors.
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Huoy L, Pornruangwong S, Pulsrikarn C, Chaturongakul S. Molecular Characterization of Thai Salmonella enterica Serotype Typhimurium and Serotype 4,5,12:i:- Reveals Distinct Genetic Deletion Patterns. Foodborne Pathog Dis 2014; 11:589-92. [DOI: 10.1089/fpd.2013.1723] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Laingshun Huoy
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Srirat Pornruangwong
- National Salmonella and Shigella Center, National Institute of Health, Department of Medical Sciences, Ministry of Public Health, Nonthaburi, Thailand
| | - Chaiwat Pulsrikarn
- National Salmonella and Shigella Center, National Institute of Health, Department of Medical Sciences, Ministry of Public Health, Nonthaburi, Thailand
| | - Soraya Chaturongakul
- Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand
- Center of Excellence on Environmental Health and Toxicology, Ministry of Education, Bangkok, Thailand
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Barco L, Longo A, Lettini AA, Cortini E, Saccardin C, Minorello C, Olsen JE, Ricci A. Molecular characterization of "inconsistent" variants of Salmonella Typhimurium isolated in Italy. Foodborne Pathog Dis 2014; 11:497-9. [PMID: 24666380 DOI: 10.1089/fpd.2013.1714] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Salmonella 4,[5],12:i:- is a variant of Salmonella Typhimurium, which lacks the expression of phase-2 flagellar antigen, generally associated with the deletion of the fljB gene. Additional mechanisms involving the fljAB operon ( fljA, fljB, and hin genes) lead to the lack of expression of phase-2 flagellar antigens also in Salmonella strains harboring the fljB gene. For 20 S. 4,[5],12:i:- strains, defined as "inconsistent" Salmonella Typhimurium variants since they had phenotypically behaved as monophasic, even though the fljB gene was conserved, the fljAB operon was characterized in order to explain the ineffective expression of the phase-2 flagellar antigen. The monophasic phenotype for a first group of strains (9) was likely due to the absence of the hin gene, leading to the inhibited switch between the expression of phase-1 and phase-2 flagellar genes. For a second group of strains (5), the monophasic phenotype could be attributed to nonconservative point mutations identified in fljA and hin genes, which could hamper the proper expression of invertase gene and the fljA, acting as repressor of the phase-1 flagellar gene. Finally, for a last group of inconsistent strains (6), a plausible reason for their monophasic phenotype was not found, since the genes involved in the expression of phase-2 flagellar antigen were fully conserved. Moreover, the collection of inconsistent Salmonella Typhimurium isolates investigated were characterized by distinct molecular profiles, as demonstrated by multiple-locus variable-number tandem repeat analysis, and phenotype variability, as demonstrated by phage-typing. This study highlights the usefulness of investigating the entire fljAB operon when a definitive identification of the monophasic or biphasic status of Salmonella Typhimurium strains is needed (for instance, in the context of epidemiological investigations aimed to identify the relatedness among strains).
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Affiliation(s)
- Lisa Barco
- 1 World Organization for Animal Health (OIE), National Reference Laboratory for Salmonella , Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro (Padova), Italy
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The European Union Summary Report on antimicrobial resistance in zoonotic and indicator bacteria from humans, animals and food in 2012. EFSA J 2014. [DOI: 10.2903/j.efsa.2014.3590] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
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Boland C, Bertrand S, Mattheus W, Dierick K, Wattiau P. Molecular typing of monophasic Salmonella 4,[5]:i:- strains isolated in Belgium (2008-2011). Vet Microbiol 2013; 168:447-50. [PMID: 24398228 DOI: 10.1016/j.vetmic.2013.11.040] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Revised: 11/22/2013] [Accepted: 11/30/2013] [Indexed: 11/28/2022]
Abstract
To assess the distribution of Salmonella 4,[5]:i:- subtypes in the Belgian food chain and compare it to the subtypes associated with human infections, a molecular assessment was initiated. Two hundred fifty-three Salmonella isolates serotyped as 4,[5]:i:- during the period 2008-2011 in Belgium and originating from animal productions, food or human clinical samples were analysed by a specific duplex PCR. One hundred ninety-four isolates (76.7%) fit the profile of a S. Typhimurium monophasic variant as defined by the European Food Safety Authority. The other isolates possessed but did not express the phase II flagellin gene (23.3%). Multiple Locus Variable Number of Tandem Repeats Analysis (MLVA) revealed many but closely related profiles in the fljB-negative S. Typhimurium monophasic variant isolates. Some MLVA types were associated with both human and animal isolates but no unique source of human contamination could be demonstrated.
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Affiliation(s)
- Cécile Boland
- Veterinary & Agrochemical Research Centre, Foodborne Bacterial Zoonoses & Antibiotic Resistance Unit, Groeselenbergstr. 99, B-1180 Brussels, Belgium
| | - Sophie Bertrand
- National Reference Centre for Salmonella and Shigella, Bacterial Diseases Division, Communicable and Infectious Diseases, Scientific Institute of Public Health, Wytsmanstreet 14, B-1050 Brussels, Belgium
| | - Wesley Mattheus
- National Reference Centre for Salmonella and Shigella, Bacterial Diseases Division, Communicable and Infectious Diseases, Scientific Institute of Public Health, Wytsmanstreet 14, B-1050 Brussels, Belgium
| | - Katelijne Dierick
- Scientific Service Food-borne Pathogens, Communicable and Infectious Diseases, Scientific Institute of Public Health, Wytsmanstreet 14, B-1050 Brussels, Belgium
| | - Pierre Wattiau
- Veterinary & Agrochemical Research Centre, Foodborne Bacterial Zoonoses & Antibiotic Resistance Unit, Groeselenbergstr. 99, B-1180 Brussels, Belgium.
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Barco L, Ramon E, Cortini E, Longo A, Dalla Pozza MC, Lettini AA, Dionisi AM, Olsen JE, Ricci A. Molecular characterization of Salmonella enterica serovar 4,[5],12:i:- DT193 ASSuT strains from two outbreaks in Italy. Foodborne Pathog Dis 2013; 11:138-44. [PMID: 24328499 DOI: 10.1089/fpd.2013.1626] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Salmonella enterica subsp. enterica serovar 4,[5],12:i:- DT193 is recognized as an emerging monophasic variant of Salmonella Typhimurium in many European countries. Resistance to ampicillin, streptomycin, sulphonamides, and tetracycline (R-type ASSuT) is described as one of the most common profiles of resistance within this clone. Recently, strains presenting such features were isolated from two unrelated outbreaks in Italy. Strains were characterized by pulsed-field gel electrophoresis (PFGE), performed with XbaI, BlnI, and SpeI, and multiple-locus variable-number tandem repeat analysis (MLVA). XbaI-PFGE showed strains related to the two outbreaks as indistinguishable. Conversely, both BlnI-PFGE and MLVA characterized the strains related the two outbreaks as different. XbaI-PFGE identified two profiles, differing by one band, within strains isolated from one of the two outbreaks. Also BlnI-PFGE and MLVA generated different profiles among the strains related to that outbreak. Combining the PFGE profiles obtained by XbaI and BlnI and comparing them with the MLVA profiles, the two methods grouped the same isolates based on identity. Moreover, genomic deletions of the genes included in the operon fljAB, the flanking iroB gene, and the closely located STM2757 gene were investigated. For all strains, the same profile of deletion characterized by the absence of fljA, fljB, and hin genes and the presence of STM2757 and iroB genes was identified. This profile of deletion represents a mixture between two profiles of Salmonella 4,[5],12:i:- described as the "Spanish" and the "U.S." clones. This study demonstrated that although strains of Salmonella 4,[5],12:i:- DT193 ASSuT are highly clonal, minor differences between strains may be seen during the same outbreak by using in parallel PFGE with different restriction enzymes, MLVA, and the analysis of molecular markers related to the operon fljAB. The combination of these different molecular approaches was essential to clarify the epidemiological relationship among the strains.
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Affiliation(s)
- Lisa Barco
- 1 World Organization for Animal Health (OIE), National Reference Laboratory for Salmonella, Istituto Zooprofilattico Sperimentale delle Venezie , Legnaro (Padova), Italy
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Scientific Opinion on the evaluation of molecular typing methods for major food‐borne microbiological hazards and their use for attribution modelling, outbreak investigation and scanning surveillance: Part 1 (evaluation of methods and applications). EFSA J 2013. [DOI: 10.2903/j.efsa.2013.3502] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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