Journal article
Characterization of sulphonamide-resistant Escherichia coli using comparison of sul2 gene sequences and multilocus sequence typing
Statens Serum Institut1
Department of Microbiology, Technical University of Denmark2
University of Copenhagen3
National Veterinary Institute4
Section of Poultry Diseases, Division of Poultry, Fish and Fur Animals, National Veterinary Institute, Technical University of Denmark5
Division of Poultry, Fish and Fur Animals, National Veterinary Institute, Technical University of Denmark6
National Veterinary Institute, Technical University of Denmark7
Division of Microbiology and Risk Assessment, National Food Institute, Technical University of Denmark8
National Food Institute, Technical University of Denmark9
University of Tromsø – The Arctic University of Norway10
...and 0 moreThe sul2 gene encodes sulphonamide resistance (Sul(R)) and is commonly found in Escherichia coli from different hosts. We typed E coli isolates by multilocus sequence typing (MLST) and compared the results to sequence variation of sul2, in order to investigate the relation to host origin of pathogenic and commensal E coli strains and to investigate whether transfer of sul2 into different genomic lineages has happened multiple times.
Sixty-eight E coli isolated in Denmark and Norway from different hosts and years were MLST typed and sul2 PCR products were sequenced and compared. PFGE was performed in a subset of isolates. All isolates were divided into 45 different sequence types (STs), with clonal complexes CC10, CC23, CC168, CC350 and CC69 being the most frequent.
The sul2 gene from the majority of E coli strains had only two point mutations, at positions 159 and 197, leading to a synonymous and a non-synonymous change, respectively. Five strains had extra single mutations. All poultry, poultry meat, and Danish human blood isolates had the same sul2 ST and some of these strains clustered under the same MLST STs, indicating that they shared habitats.
Most PFGE profiles clustered according to source, but some included different sources. Sul(R) E coli from different animals, food, human faeces and infections did not cluster according to their origin, suggesting that these habitats share E coli and sul2 gene types. However, while pig isolates on one occasion clustered with urinary tract infection isolates, poultry isolates seemed more related to isolates from bloodstream infections in humans.
Presence of mainly two types of the sul2 gene in both human and animal isolates, irrespective of date and geography, and the presence of both types in the same clonal lineages, suggest horizontal transfer of sul2.
Language: | English |
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Publisher: | Society for General Microbiology |
Year: | 2009 |
Pages: | 831-836 |
ISSN: | 14652080 and 13500872 |
Types: | Journal article |
DOI: | 10.1099/mic.0.024190-0 |
ORCIDs: | 0000-0003-4238-4658 and 0000-0001-6225-6587 |
Animals Bacterial Proteins Bacterial Typing Techniques Base Sequence Carrier Proteins DNA, Bacterial Denmark Escherichia coli Escherichia coli Proteins Feces Food Microbiology Gene Transfer, Horizontal Humans Meat Molecular Sequence Data Norway Point Mutation Poultry Sequence Analysis, DNA Sul2 protein, bacteria Swine