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François-xavier Weill - One of the best experts on this subject based on the ideXlab platform.
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Early transmissible Ampicillin Resistance in zoonotic Salmonella enterica serotype Typhimurium in the late 1950s: a retrospective, whole-genome sequencing study
The Lancet Infectious Diseases, 2018Co-Authors: Alicia Tran-dien, Simon Le Hello, Christiane Bouchier, François-xavier WeillAbstract:BACKGROUND: Ampicillin, the first semi-synthetic penicillin active against Enterobacteriaceae, was released onto the market in 1961. The first outbreaks of disease caused by Ampicillin-resistant strains of Salmonella enterica serotype Typhimurium were identified in the UK in 1962 and 1964. We aimed to date the emergence of this Resistance in historical isolates of S enterica serotype Typhimurium. METHODS: In this retrospective, whole-genome sequencing study, we analysed 288 S enterica serotype Typhimurium isolates collected between 1911 and 1969 from 31 countries on four continents and from various sources including human beings, animals, feed, and food. All isolates were tested for antimicrobial drug susceptibility with the disc diffusion method, and isolates shown to be resistant to Ampicillin underwent Resistance-transfer experiments. To provide insights into population structure and mechanisms of Ampicillin Resistance, we did whole-genome sequencing on a subset of 225 isolates, selected to maximise source, spatiotemporal, and genetic diversity. FINDINGS: 11 (4%) of 288 isolates were resistant to Ampicillin because of acquisition of various β lactamase genes, including blaTEM-1, carried by various plasmids, including the virulence plasmid of S enterica serotype Typhimurium. These 11 isolates were from three phylogenomic groups. One isolate producing TEM-1 β lactamase was isolated in France in 1959 and two isolates producing TEM-1 β lactamase were isolated in Tunisia in 1960, before Ampicillin went on sale. The vectors for Ampicillin Resistance were different from those reported in the strains responsible for the outbreaks in the UK in the 1960s. INTERPRETATION: The association between antibiotic use and selection of Resistance determinants is not as direct as often presumed. Our results suggest that the non-clinical use of narrow-spectrum penicillins (eg, benzylpenicillin) might have favoured the diffusion of plasmids carrying the blaTEM-1 gene in S enterica serotype Typhimurium in the late 1950s.
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Early transmissible Ampicillin Resistance in zoonotic Salmonella enterica serotype Typhimurium in the late 1950s: a retrospective, whole-genome sequencing study
The Lancet Infectious Diseases, 2018Co-Authors: Alicia Tran-dien, Simon Le Hello, Christiane Bouchier, François-xavier WeillAbstract:Summary Background Ampicillin, the first semi-synthetic penicillin active against Enterobacteriaceae, was released onto the market in 1961. The first outbreaks of disease caused by Ampicillin-resistant strains of Salmonella enterica serotype Typhimurium were identified in the UK in 1962 and 1964. We aimed to date the emergence of this Resistance in historical isolates of S enterica serotype Typhimurium. Methods In this retrospective, whole-genome sequencing study, we analysed 288 S enterica serotype Typhimurium isolates collected between 1911 and 1969 from 31 countries on four continents and from various sources including human beings, animals, feed, and food. All isolates were tested for antimicrobial drug susceptibility with the disc diffusion method, and isolates shown to be resistant to Ampicillin underwent Resistance-transfer experiments. To provide insights into population structure and mechanisms of Ampicillin Resistance, we did whole-genome sequencing on a subset of 225 isolates, selected to maximise source, spatiotemporal, and genetic diversity. Findings 11 (4%) of 288 isolates were resistant to Ampicillin because of acquisition of various β lactamase genes, including bla TEM-1 , carried by various plasmids, including the virulence plasmid of S enterica serotype Typhimurium. These 11 isolates were from three phylogenomic groups. One isolate producing TEM-1 β lactamase was isolated in France in 1959 and two isolates producing TEM-1 β lactamase were isolated in Tunisia in 1960, before Ampicillin went on sale. The vectors for Ampicillin Resistance were different from those reported in the strains responsible for the outbreaks in the UK in the 1960s. Interpretation The association between antibiotic use and selection of Resistance determinants is not as direct as often presumed. Our results suggest that the non-clinical use of narrow-spectrum penicillins (eg, benzylpenicillin) might have favoured the diffusion of plasmids carrying the bla TEM-1 gene in S enterica serotype Typhimurium in the late 1950s. Funding Institut Pasteur, Sante publique France, the French Government's Investissement d'Avenir programme, the Fondation Le Roch-Les Mousquetaires.
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Molecular Epidemiology of Ampicillin Resistance in Salmonella spp. and Escherichia coli from Wastewater and Clinical Specimens
Foodborne Pathogens and Disease, 2010Co-Authors: Sarina Pignato, Maria Anna Coniglio, Martine Lefevre, François-xavier Weill, Giuseppina Faro, Giuseppe GiammancoAbstract:Molecular epidemiology at local scale in Sicily (Italy) of Ampicillin Resistance in Salmonella spp. isolates from municipal wastewater (n ¼ 64) and clinical specimens (n ¼ 274) is described in comparison with previously examined Escherichia coli isolates (n ¼ 273) from wastewater. High prevalence of antibiotic Resistance (28.9%) with highest Resistance rates against Ampicillin (22.7%) was observed in E. coli isolates. Different Resistance rates were observed in Salmonella according to the serovars, with prevalences of the same order in both wastewater and clinical isolates belonging to the same serovar (e.g., 91.7% Ampicillin Resistance in wastewater isolates vs. 70.8% in clinical isolates of the Salmonella serovar Typhimurium and 0% Ampicillin Resistance in both wastewater and clinical isolates of the Salmonella serovar Enteritidis). The b-lactam Resistance gene bla TEM was present in both wastewater and clinical Salmonella spp. isolates, with the exception of Salmonella enterica serovar Typhimurium isolates with a typical six-drug Resistance pattern AmpChlSulTeStrSp that had the bla PSE-1 gene. The bla TEM gene was present in all the E. coli isolates but one had the bla SHV gene. Several E. coli and some Salmonella isolates were positive for class 1 integrons with variable regions of 1.0 or 1.5 kb containing aadA1, dfrA17-aadA5, or dfrA1-aadA1 gene cassettes, whereas Salmonella serovar Typhimurium isolates with the six-drug Resistance pattern were positive for both 1.0 and 1.2 kb integrons. Polymerase chain reaction replicon typing demonstrated the presence of multireplicon Resistance plasmids in several isolates of E. coli, containing two to four of the replicons IncF, IncI1, IncFIA, and IncFIB, whereas other isolates showed Resistance plasmids with only IncF, IncP, or IncK replicons. Replicon IncI1 was detected in one Salmonella isolate, whereas other isolates belonging to different serovars had IncN replicons. Analysis of isolates from wastewater can be a useful epidemiologic tool to monitor the prevalence of antibiotic Resistance and genetic elements related to antibiotic Resistance in Salmonella clones circulating in the human population.
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Molecular Epidemiology of Ampicillin Resistance in Salmonella spp. and Escherichia coli from Wastewater and Clinical Specimens
Foodborne Pathogens and Disease, 2010Co-Authors: Sarina Pignato, Maria Anna Coniglio, Faro G, Martine Lefevre, François-xavier Weill, Giuseppe GiammancoAbstract:Abstract Molecular epidemiology at local scale in Sicily (Italy) of Ampicillin Resistance in Salmonella spp. isolates from municipal wastewater (n = 64) and clinical specimens (n = 274) is described in comparison with previously examined Escherichia coli isolates (n = 273) from wastewater. High prevalence of antibiotic Resistance (28.9%) with highest Resistance rates against Ampicillin (22.7%) was observed in E. coli isolates. Different Resistance rates were observed in Salmonella according to the serovars, with prevalences of the same order in both wastewater and clinical isolates belonging to the same serovar (e.g., 91.7% Ampicillin Resistance in wastewater isolates vs. 70.8% in clinical isolates of the Salmonella serovar Typhimurium and 0% Ampicillin Resistance in both wastewater and clinical isolates of the Salmonella serovar Enteritidis). The β-lactam Resistance gene blaTEM was present in both wastewater and clinical Salmonella spp. isolates, with the exception of Salmonella enterica serovar Typhimur...
Alicia Tran-dien - One of the best experts on this subject based on the ideXlab platform.
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Early transmissible Ampicillin Resistance in zoonotic Salmonella enterica serotype Typhimurium in the late 1950s: a retrospective, whole-genome sequencing study
The Lancet Infectious Diseases, 2018Co-Authors: Alicia Tran-dien, Simon Le Hello, Christiane Bouchier, François-xavier WeillAbstract:BACKGROUND: Ampicillin, the first semi-synthetic penicillin active against Enterobacteriaceae, was released onto the market in 1961. The first outbreaks of disease caused by Ampicillin-resistant strains of Salmonella enterica serotype Typhimurium were identified in the UK in 1962 and 1964. We aimed to date the emergence of this Resistance in historical isolates of S enterica serotype Typhimurium. METHODS: In this retrospective, whole-genome sequencing study, we analysed 288 S enterica serotype Typhimurium isolates collected between 1911 and 1969 from 31 countries on four continents and from various sources including human beings, animals, feed, and food. All isolates were tested for antimicrobial drug susceptibility with the disc diffusion method, and isolates shown to be resistant to Ampicillin underwent Resistance-transfer experiments. To provide insights into population structure and mechanisms of Ampicillin Resistance, we did whole-genome sequencing on a subset of 225 isolates, selected to maximise source, spatiotemporal, and genetic diversity. FINDINGS: 11 (4%) of 288 isolates were resistant to Ampicillin because of acquisition of various β lactamase genes, including blaTEM-1, carried by various plasmids, including the virulence plasmid of S enterica serotype Typhimurium. These 11 isolates were from three phylogenomic groups. One isolate producing TEM-1 β lactamase was isolated in France in 1959 and two isolates producing TEM-1 β lactamase were isolated in Tunisia in 1960, before Ampicillin went on sale. The vectors for Ampicillin Resistance were different from those reported in the strains responsible for the outbreaks in the UK in the 1960s. INTERPRETATION: The association between antibiotic use and selection of Resistance determinants is not as direct as often presumed. Our results suggest that the non-clinical use of narrow-spectrum penicillins (eg, benzylpenicillin) might have favoured the diffusion of plasmids carrying the blaTEM-1 gene in S enterica serotype Typhimurium in the late 1950s.
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Early transmissible Ampicillin Resistance in zoonotic Salmonella enterica serotype Typhimurium in the late 1950s: a retrospective, whole-genome sequencing study
The Lancet Infectious Diseases, 2018Co-Authors: Alicia Tran-dien, Simon Le Hello, Christiane Bouchier, François-xavier WeillAbstract:Summary Background Ampicillin, the first semi-synthetic penicillin active against Enterobacteriaceae, was released onto the market in 1961. The first outbreaks of disease caused by Ampicillin-resistant strains of Salmonella enterica serotype Typhimurium were identified in the UK in 1962 and 1964. We aimed to date the emergence of this Resistance in historical isolates of S enterica serotype Typhimurium. Methods In this retrospective, whole-genome sequencing study, we analysed 288 S enterica serotype Typhimurium isolates collected between 1911 and 1969 from 31 countries on four continents and from various sources including human beings, animals, feed, and food. All isolates were tested for antimicrobial drug susceptibility with the disc diffusion method, and isolates shown to be resistant to Ampicillin underwent Resistance-transfer experiments. To provide insights into population structure and mechanisms of Ampicillin Resistance, we did whole-genome sequencing on a subset of 225 isolates, selected to maximise source, spatiotemporal, and genetic diversity. Findings 11 (4%) of 288 isolates were resistant to Ampicillin because of acquisition of various β lactamase genes, including bla TEM-1 , carried by various plasmids, including the virulence plasmid of S enterica serotype Typhimurium. These 11 isolates were from three phylogenomic groups. One isolate producing TEM-1 β lactamase was isolated in France in 1959 and two isolates producing TEM-1 β lactamase were isolated in Tunisia in 1960, before Ampicillin went on sale. The vectors for Ampicillin Resistance were different from those reported in the strains responsible for the outbreaks in the UK in the 1960s. Interpretation The association between antibiotic use and selection of Resistance determinants is not as direct as often presumed. Our results suggest that the non-clinical use of narrow-spectrum penicillins (eg, benzylpenicillin) might have favoured the diffusion of plasmids carrying the bla TEM-1 gene in S enterica serotype Typhimurium in the late 1950s. Funding Institut Pasteur, Sante publique France, the French Government's Investissement d'Avenir programme, the Fondation Le Roch-Les Mousquetaires.
Stefan Schwarz - One of the best experts on this subject based on the ideXlab platform.
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physical linkage of tn3 and part of tn1721 in a tetracycline and Ampicillin Resistance plasmid from salmonella typhimurium
Journal of Antimicrobial Chemotherapy, 2005Co-Authors: Frederique Pasquali, Corinna Kehrenberg, Gerardo Manfreda, Stefan SchwarzAbstract:OBJECTIVES: The complete nucleotide sequence of the 12 656 bp plasmid pFPTB1 from Salmonella enterica subsp. enterica serovar Typhimurium, which mediates Resistance to tetracyclines and Ampicillin, was determined. The plasmid was analysed for potential reading frames and structural features indicative of transposons and transposon relics. METHODS: Plasmid pFPTB1 was transformed into Escherichia coli JM109, overlapping restriction fragments were cloned into E. coli plasmid vectors and sequenced. In vitro susceptibility testing was carried out to confirm the Resistance phenotype mediated by this plasmid. RESULTS: Plasmid pFPTB1 contains a complete Tn3-like transposon of 4950 bp consisting of the left terminal repeat, Tn3-related tnpR and tnpA genes for transposition functions, a novel gene for Ampicillin Resistance bla(TEM-135), and the right terminal repeat. Immediately downstream, the terminal 5215 bp at the right end of a Tn1721-like transposon, including the right terminal repeat, a truncated transposase gene, as well as the genes tet(A) and tetR for tetracycline Resistance, were detected. A 5 bp direct repeat, TAAAA, was seen immediately upstream of the Tn3 part and immediately downstream of the Tn1721 part. Plasmid pFPTB1 also carries a replication region similar to that of the Klebsiella pneumoniae plasmid pJHCMW1. CONCLUSION: Plasmid pFPTB1 is one of the few completely sequenced plasmids from S. Typhimurium and harbours a novel transposon-like structure consisting of a Tn3-related part containing the bla(TEM-135) gene for Ampicillin Resistance and a Tn1721-related part containing the tetR-tet(A) genes for tetracycline Resistance.
Nina Langeland - One of the best experts on this subject based on the ideXlab platform.
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role of penicillin binding protein 5 c terminal amino acid substitutions in conferring Ampicillin Resistance in norwegian clinical strains of enterococcus faecium
Apmis, 2004Co-Authors: Roland Jureen, Stein Christian Mohn, Stig Harthug, Lars Haarr, Nina LangelandAbstract:The importance of amino acid sequence differences in the C-terminal part and levels of mRNA expression of penicillin-binding protein 5 (PBP5) for Ampicillin Resistance in Enterococcus faecium was investigated. Seventeen isolates from Norwegian hospitalized patients (Ampicillin MIC 0.064->256 mg/L) with different C-terminal pbp5 DNA sequences encoding 11 different amino acid sequences were analyzed with a 14C-radiolabeled penicillin- binding assay to PBP5 and with real-time PCR quantification of pbp5 mRNA expression. Using multiple logistic regression analysis the amino acid substitution Met 485 was linked to Ampicillin MIC and levels of 14C-radiolabeled penicillin bound to PBP5; however, there were isolates with identical PBP5 alleles and different Ampicillin MICs. There was no relation between the quantity of pbp5 mRNA transcripts and Ampicillin Resistance. The results cannot explain Ampicillin Resistance in Norwegian clinical strains of E. faecium and indicate that other factors besides the properties of the C-terminal part of PBP5 are most likely involved.
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Role of penicillin‐binding protein 5 C‐terminal amino acid substitutions in conferring Ampicillin Resistance in Norwegian clinical strains of Enterococcus faecium
APMIS, 2004Co-Authors: Roland Jureen, Stein Christian Mohn, Stig Harthug, Lars Haarr, Nina LangelandAbstract:The importance of amino acid sequence differences in the C-terminal part and levels of mRNA expression of penicillin-binding protein 5 (PBP5) for Ampicillin Resistance in Enterococcus faecium was investigated. Seventeen isolates from Norwegian hospitalized patients (Ampicillin MIC 0.064->256 mg/L) with different C-terminal pbp5 DNA sequences encoding 11 different amino acid sequences were analyzed with a 14C-radiolabeled penicillin- binding assay to PBP5 and with real-time PCR quantification of pbp5 mRNA expression. Using multiple logistic regression analysis the amino acid substitution Met 485 was linked to Ampicillin MIC and levels of 14C-radiolabeled penicillin bound to PBP5; however, there were isolates with identical PBP5 alleles and different Ampicillin MICs. There was no relation between the quantity of pbp5 mRNA transcripts and Ampicillin Resistance. The results cannot explain Ampicillin Resistance in Norwegian clinical strains of E. faecium and indicate that other factors besides the properties of the C-terminal part of PBP5 are most likely involved.
Giuseppe Giammanco - One of the best experts on this subject based on the ideXlab platform.
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Molecular Epidemiology of Ampicillin Resistance in Salmonella spp. and Escherichia coli from Wastewater and Clinical Specimens
Foodborne Pathogens and Disease, 2010Co-Authors: Sarina Pignato, Maria Anna Coniglio, Martine Lefevre, François-xavier Weill, Giuseppina Faro, Giuseppe GiammancoAbstract:Molecular epidemiology at local scale in Sicily (Italy) of Ampicillin Resistance in Salmonella spp. isolates from municipal wastewater (n ¼ 64) and clinical specimens (n ¼ 274) is described in comparison with previously examined Escherichia coli isolates (n ¼ 273) from wastewater. High prevalence of antibiotic Resistance (28.9%) with highest Resistance rates against Ampicillin (22.7%) was observed in E. coli isolates. Different Resistance rates were observed in Salmonella according to the serovars, with prevalences of the same order in both wastewater and clinical isolates belonging to the same serovar (e.g., 91.7% Ampicillin Resistance in wastewater isolates vs. 70.8% in clinical isolates of the Salmonella serovar Typhimurium and 0% Ampicillin Resistance in both wastewater and clinical isolates of the Salmonella serovar Enteritidis). The b-lactam Resistance gene bla TEM was present in both wastewater and clinical Salmonella spp. isolates, with the exception of Salmonella enterica serovar Typhimurium isolates with a typical six-drug Resistance pattern AmpChlSulTeStrSp that had the bla PSE-1 gene. The bla TEM gene was present in all the E. coli isolates but one had the bla SHV gene. Several E. coli and some Salmonella isolates were positive for class 1 integrons with variable regions of 1.0 or 1.5 kb containing aadA1, dfrA17-aadA5, or dfrA1-aadA1 gene cassettes, whereas Salmonella serovar Typhimurium isolates with the six-drug Resistance pattern were positive for both 1.0 and 1.2 kb integrons. Polymerase chain reaction replicon typing demonstrated the presence of multireplicon Resistance plasmids in several isolates of E. coli, containing two to four of the replicons IncF, IncI1, IncFIA, and IncFIB, whereas other isolates showed Resistance plasmids with only IncF, IncP, or IncK replicons. Replicon IncI1 was detected in one Salmonella isolate, whereas other isolates belonging to different serovars had IncN replicons. Analysis of isolates from wastewater can be a useful epidemiologic tool to monitor the prevalence of antibiotic Resistance and genetic elements related to antibiotic Resistance in Salmonella clones circulating in the human population.
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Molecular Epidemiology of Ampicillin Resistance in Salmonella spp. and Escherichia coli from Wastewater and Clinical Specimens
Foodborne Pathogens and Disease, 2010Co-Authors: Sarina Pignato, Maria Anna Coniglio, Faro G, Martine Lefevre, François-xavier Weill, Giuseppe GiammancoAbstract:Abstract Molecular epidemiology at local scale in Sicily (Italy) of Ampicillin Resistance in Salmonella spp. isolates from municipal wastewater (n = 64) and clinical specimens (n = 274) is described in comparison with previously examined Escherichia coli isolates (n = 273) from wastewater. High prevalence of antibiotic Resistance (28.9%) with highest Resistance rates against Ampicillin (22.7%) was observed in E. coli isolates. Different Resistance rates were observed in Salmonella according to the serovars, with prevalences of the same order in both wastewater and clinical isolates belonging to the same serovar (e.g., 91.7% Ampicillin Resistance in wastewater isolates vs. 70.8% in clinical isolates of the Salmonella serovar Typhimurium and 0% Ampicillin Resistance in both wastewater and clinical isolates of the Salmonella serovar Enteritidis). The β-lactam Resistance gene blaTEM was present in both wastewater and clinical Salmonella spp. isolates, with the exception of Salmonella enterica serovar Typhimur...