TY - JOUR
T1 - Limited similarity between plasmids encoding CTX-M-1 β-lactamase in Escherichia coli from humans, pigs, cattle, organic poultry layers and horses in Denmark
AU - Jakobsen, Lotte
AU - Bortolaia, Valeria
AU - Bielak, Eliza
AU - Moodley, Arshnee
AU - Olsen, Stefan S.
AU - Hansen, Dennis S.
AU - Frimodt-Møller, Niels
AU - Guardabassi, Luca
AU - Hasman, Henrik
PY - 2015/6
Y1 - 2015/6
N2 - CTX-M-1 is a common extended-spectrum β-lactamase (ESBL) in Escherichia coli from animals and is often detected among human clinical isolates. The objective of this study was to investigate the epidemiological relationship between CTX-M-1-producing E. coli isolated from patients and animals in Denmark between 2006 and 2010. In total, 65 CTX-M-1-producing isolates from patients (n = 22), pigs (n = 21), cattle (n = 4), organic poultry layers (n = 3) and horses (n = 15) were typed by pulsed-field gel electrophoresis (PFGE). Plasmids harbouring blaCTX-M-1 were characterised by S1 PFGE, PCR-based replicon typing, plasmid multilocus sequence typing, restriction fragment length polymorphism, and sequencing. Human and animal strains were unrelated based on PFGE. IncI1 was more common in human isolates (13/22) than in animal isolates (7/43), whereas the opposite trend was observed for IncN (5/22 human isolates and 24/43 animal isolates). Full characterisation of the plasmids harbouring blaCTX-M-1 revealed host-specific patterns in the distribution of plasmid types, with specific IncI1, IncN and IncH1 plasmid subtypes being predominant in humans, livestock and horses, respectively. Three indistinguishable human, bovine and porcine IncI1/ST49 plasmids had high nucleotide sequence homology and differed by the presence of IS66 elements in the bovine plasmid and the absence of one gene within the microcin-encoding operon in the human plasmid. In conclusion, this work suggests a minor contribution by animals to the occurrence of CTX-M-1 in human E. coli infections in Denmark during the study period.
AB - CTX-M-1 is a common extended-spectrum β-lactamase (ESBL) in Escherichia coli from animals and is often detected among human clinical isolates. The objective of this study was to investigate the epidemiological relationship between CTX-M-1-producing E. coli isolated from patients and animals in Denmark between 2006 and 2010. In total, 65 CTX-M-1-producing isolates from patients (n = 22), pigs (n = 21), cattle (n = 4), organic poultry layers (n = 3) and horses (n = 15) were typed by pulsed-field gel electrophoresis (PFGE). Plasmids harbouring blaCTX-M-1 were characterised by S1 PFGE, PCR-based replicon typing, plasmid multilocus sequence typing, restriction fragment length polymorphism, and sequencing. Human and animal strains were unrelated based on PFGE. IncI1 was more common in human isolates (13/22) than in animal isolates (7/43), whereas the opposite trend was observed for IncN (5/22 human isolates and 24/43 animal isolates). Full characterisation of the plasmids harbouring blaCTX-M-1 revealed host-specific patterns in the distribution of plasmid types, with specific IncI1, IncN and IncH1 plasmid subtypes being predominant in humans, livestock and horses, respectively. Three indistinguishable human, bovine and porcine IncI1/ST49 plasmids had high nucleotide sequence homology and differed by the presence of IS66 elements in the bovine plasmid and the absence of one gene within the microcin-encoding operon in the human plasmid. In conclusion, this work suggests a minor contribution by animals to the occurrence of CTX-M-1 in human E. coli infections in Denmark during the study period.
KW - Faculty of Health and Medical Sciences
KW - Escherichia coli
KW - CTX-M-1
KW - Incl1
KW - IncN
KW - Plasmid sequencing
KW - Humans and animals
U2 - 10.1016/j.jgar.2015.03.009
DO - 10.1016/j.jgar.2015.03.009
M3 - Journal article
SN - 2213-7165
VL - 3
SP - 132
EP - 136
JO - Journal of Global Antimicrobial Resistance
JF - Journal of Global Antimicrobial Resistance
IS - 2
ER -