Molecular characterisation of multidrug-resistant Salmonella enterica serotype Infantis from humans, animals and the environment in Italy

Anna Maria Dionisi, Claudia Lucarelli, Ildo Benedetti, Slawomir Owczarek, Ida Luzzi

Research output: Contribution to journalArticle

Abstract

During 2005-2006, Salmonella enterica serotype Infantis strains isolated from human and non-human sources and resistant to ampicillin (A), chloramphenicol (C), streptomycin (S), sulphonamide (Su), tetracycline (T), kanamycin (K) and trimethoprim/sulfamethoxazole (Sxt) emerged in Italy. The aim of this study was to analyse the molecular basis of antibiotic resistance and to evaluate the clonal origin of multiresistant S. Infantis strains isolated from different sources. Seventy S. Infantis strains, susceptible or resistant to antimicrobial drugs, were chosen for this study. Polymerase chain reaction (PCR) and conjugation experiments were performed to identify and localise the resistance genes in multidrug-resistant strains. PCR-based replicon typing was carried out for characterisation of conjugative plasmids. All strains were tested by pulsed-field gel electrophoresis (PFGE) according to the PulseNet protocol, and cluster analysis was performed using BioNumerics software. Strains with resistance (R)-type ACSSuTKSxt harboured bla(TEM-1), strA-B, sul2, tet(B), catA1 and aphA-1 resistance genes as well as a 2.2-kb class 1 integron containing folA, catB3, aadA4 and sul1 gene cassettes. A unique plasmid, belonging to the HI1 incompatibility group, harboured all the resistance genes. Cluster analysis showed that all ACSSuTKSxt-resistant strains belonged to a large cluster (A) with >90% genetic similarity. The presence of a plasmid harbouring all the resistance gene cassettes as well as molecular typing by PFGE demonstrated the circulation of a cluster of S. Infantis R-type ACSSuTKSxt during 2005-2006 in Italy. The presence of a plasmid conferring multidrug resistance could have facilitated the spread of a group of similar isolates through a variety of sources.

Original languageEnglish
Pages (from-to)384-9
Number of pages6
JournalInternational Journal of Antimicrobial Agents
Volume38
Issue number5
DOIs
Publication statusPublished - Nov 2011

Fingerprint

Salmonella enterica
Italy
Plasmids
Pulsed Field Gel Electrophoresis
Genes
Cluster Analysis
Integrons
MDR Genes
Molecular Typing
Polymerase Chain Reaction
Replicon
Kanamycin
Sulfonamides
Sulfamethoxazole Drug Combination Trimethoprim
Multiple Drug Resistance
Streptomycin
Chloramphenicol
Ampicillin
Microbial Drug Resistance
Tetracycline

Keywords

  • Animals
  • Anti-Bacterial Agents/pharmacology
  • Conjugation, Genetic
  • DNA, Bacterial/genetics
  • Drug Resistance, Multiple, Bacterial/genetics
  • Electrophoresis, Gel, Pulsed-Field
  • Humans
  • Italy/epidemiology
  • Microbial Sensitivity Tests
  • Plasmids/genetics
  • Polymerase Chain Reaction/methods
  • Salmonella Infections/microbiology
  • Salmonella Infections, Animal/microbiology
  • Salmonella enterica/classification
  • Serotyping
  • Water Microbiology

Cite this

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title = "Molecular characterisation of multidrug-resistant Salmonella enterica serotype Infantis from humans, animals and the environment in Italy",
abstract = "During 2005-2006, Salmonella enterica serotype Infantis strains isolated from human and non-human sources and resistant to ampicillin (A), chloramphenicol (C), streptomycin (S), sulphonamide (Su), tetracycline (T), kanamycin (K) and trimethoprim/sulfamethoxazole (Sxt) emerged in Italy. The aim of this study was to analyse the molecular basis of antibiotic resistance and to evaluate the clonal origin of multiresistant S. Infantis strains isolated from different sources. Seventy S. Infantis strains, susceptible or resistant to antimicrobial drugs, were chosen for this study. Polymerase chain reaction (PCR) and conjugation experiments were performed to identify and localise the resistance genes in multidrug-resistant strains. PCR-based replicon typing was carried out for characterisation of conjugative plasmids. All strains were tested by pulsed-field gel electrophoresis (PFGE) according to the PulseNet protocol, and cluster analysis was performed using BioNumerics software. Strains with resistance (R)-type ACSSuTKSxt harboured bla(TEM-1), strA-B, sul2, tet(B), catA1 and aphA-1 resistance genes as well as a 2.2-kb class 1 integron containing folA, catB3, aadA4 and sul1 gene cassettes. A unique plasmid, belonging to the HI1 incompatibility group, harboured all the resistance genes. Cluster analysis showed that all ACSSuTKSxt-resistant strains belonged to a large cluster (A) with >90{\%} genetic similarity. The presence of a plasmid harbouring all the resistance gene cassettes as well as molecular typing by PFGE demonstrated the circulation of a cluster of S. Infantis R-type ACSSuTKSxt during 2005-2006 in Italy. The presence of a plasmid conferring multidrug resistance could have facilitated the spread of a group of similar isolates through a variety of sources.",
keywords = "Animals, Anti-Bacterial Agents/pharmacology, Conjugation, Genetic, DNA, Bacterial/genetics, Drug Resistance, Multiple, Bacterial/genetics, Electrophoresis, Gel, Pulsed-Field, Humans, Italy/epidemiology, Microbial Sensitivity Tests, Plasmids/genetics, Polymerase Chain Reaction/methods, Salmonella Infections/microbiology, Salmonella Infections, Animal/microbiology, Salmonella enterica/classification, Serotyping, Water Microbiology",
author = "Dionisi, {Anna Maria} and Claudia Lucarelli and Ildo Benedetti and Slawomir Owczarek and Ida Luzzi",
note = "Copyright {\circledC} 2011 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.",
year = "2011",
month = "11",
doi = "10.1016/j.ijantimicag.2011.07.001",
language = "English",
volume = "38",
pages = "384--9",
journal = "International Journal of Antimicrobial Agents",
issn = "0924-8579",
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number = "5",

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TY - JOUR

T1 - Molecular characterisation of multidrug-resistant Salmonella enterica serotype Infantis from humans, animals and the environment in Italy

AU - Dionisi, Anna Maria

AU - Lucarelli, Claudia

AU - Benedetti, Ildo

AU - Owczarek, Slawomir

AU - Luzzi, Ida

N1 - Copyright © 2011 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

PY - 2011/11

Y1 - 2011/11

N2 - During 2005-2006, Salmonella enterica serotype Infantis strains isolated from human and non-human sources and resistant to ampicillin (A), chloramphenicol (C), streptomycin (S), sulphonamide (Su), tetracycline (T), kanamycin (K) and trimethoprim/sulfamethoxazole (Sxt) emerged in Italy. The aim of this study was to analyse the molecular basis of antibiotic resistance and to evaluate the clonal origin of multiresistant S. Infantis strains isolated from different sources. Seventy S. Infantis strains, susceptible or resistant to antimicrobial drugs, were chosen for this study. Polymerase chain reaction (PCR) and conjugation experiments were performed to identify and localise the resistance genes in multidrug-resistant strains. PCR-based replicon typing was carried out for characterisation of conjugative plasmids. All strains were tested by pulsed-field gel electrophoresis (PFGE) according to the PulseNet protocol, and cluster analysis was performed using BioNumerics software. Strains with resistance (R)-type ACSSuTKSxt harboured bla(TEM-1), strA-B, sul2, tet(B), catA1 and aphA-1 resistance genes as well as a 2.2-kb class 1 integron containing folA, catB3, aadA4 and sul1 gene cassettes. A unique plasmid, belonging to the HI1 incompatibility group, harboured all the resistance genes. Cluster analysis showed that all ACSSuTKSxt-resistant strains belonged to a large cluster (A) with >90% genetic similarity. The presence of a plasmid harbouring all the resistance gene cassettes as well as molecular typing by PFGE demonstrated the circulation of a cluster of S. Infantis R-type ACSSuTKSxt during 2005-2006 in Italy. The presence of a plasmid conferring multidrug resistance could have facilitated the spread of a group of similar isolates through a variety of sources.

AB - During 2005-2006, Salmonella enterica serotype Infantis strains isolated from human and non-human sources and resistant to ampicillin (A), chloramphenicol (C), streptomycin (S), sulphonamide (Su), tetracycline (T), kanamycin (K) and trimethoprim/sulfamethoxazole (Sxt) emerged in Italy. The aim of this study was to analyse the molecular basis of antibiotic resistance and to evaluate the clonal origin of multiresistant S. Infantis strains isolated from different sources. Seventy S. Infantis strains, susceptible or resistant to antimicrobial drugs, were chosen for this study. Polymerase chain reaction (PCR) and conjugation experiments were performed to identify and localise the resistance genes in multidrug-resistant strains. PCR-based replicon typing was carried out for characterisation of conjugative plasmids. All strains were tested by pulsed-field gel electrophoresis (PFGE) according to the PulseNet protocol, and cluster analysis was performed using BioNumerics software. Strains with resistance (R)-type ACSSuTKSxt harboured bla(TEM-1), strA-B, sul2, tet(B), catA1 and aphA-1 resistance genes as well as a 2.2-kb class 1 integron containing folA, catB3, aadA4 and sul1 gene cassettes. A unique plasmid, belonging to the HI1 incompatibility group, harboured all the resistance genes. Cluster analysis showed that all ACSSuTKSxt-resistant strains belonged to a large cluster (A) with >90% genetic similarity. The presence of a plasmid harbouring all the resistance gene cassettes as well as molecular typing by PFGE demonstrated the circulation of a cluster of S. Infantis R-type ACSSuTKSxt during 2005-2006 in Italy. The presence of a plasmid conferring multidrug resistance could have facilitated the spread of a group of similar isolates through a variety of sources.

KW - Animals

KW - Anti-Bacterial Agents/pharmacology

KW - Conjugation, Genetic

KW - DNA, Bacterial/genetics

KW - Drug Resistance, Multiple, Bacterial/genetics

KW - Electrophoresis, Gel, Pulsed-Field

KW - Humans

KW - Italy/epidemiology

KW - Microbial Sensitivity Tests

KW - Plasmids/genetics

KW - Polymerase Chain Reaction/methods

KW - Salmonella Infections/microbiology

KW - Salmonella Infections, Animal/microbiology

KW - Salmonella enterica/classification

KW - Serotyping

KW - Water Microbiology

U2 - 10.1016/j.ijantimicag.2011.07.001

DO - 10.1016/j.ijantimicag.2011.07.001

M3 - Article

VL - 38

SP - 384

EP - 389

JO - International Journal of Antimicrobial Agents

JF - International Journal of Antimicrobial Agents

SN - 0924-8579

IS - 5

ER -