Genetic identity of aminoglycoside-resistance genes in Escherichia coli isolates from human and animal sources.
A bacterial collection (n=249) obtained in Hong Kong from 2002 to 2004 was used to investigate the molecular epidemiology of aminoglycoside resistance among Escherichia coli isolates from humans and food-producing animals. Of these, 89 isolates were gentamicin-sensitive (human n=60, animal n=29) and 160 isolates were gentamicin-resistant (human n=107, animal n=53). Overall, 84.1% (90/107) and 75.5% (40/53) of the gentamicin-resistant isolates from human and animal sources, respectively, were found to possess the aacC2 gene. The aacC2 gene for 20 isolates (10 each for human and animal isolates) was sequenced. Two alleles were found that were equally distributed in human and animal isolates. PFGE showed that the gentamicin-resistant isolates exhibited diverse patterns with little clonality. In some isolates, the aacC2 gene was encoded on large transferable plasmids of multiple incompatibility groups (IncF, IncI1 and IncN). An IncFII plasmid of 140 kb in size was shared by one human and three animal isolates. In summary, this study showed that human and animal isolates share the same pool of resistance genes.
Ho
Pak-Leung
PL
Department of Microbiology and Carol Yu Centre for Infection, University of Hong Kong, Hong Kong SAR.
Wong
River C
RC
Department of Clinical Pathology, Tuen Mun Hospital, Hong Kong SAR.
Lo
Stephanie W
SW
Department of Microbiology and Carol Yu Centre for Infection, University of Hong Kong, Hong Kong SAR.
Chow
Kin-Hung
KH
Department of Microbiology and Carol Yu Centre for Infection, University of Hong Kong, Hong Kong SAR.
Wong
Samson S
SS
Department of Microbiology and Carol Yu Centre for Infection, University of Hong Kong, Hong Kong SAR.
Que
Tak-Lun
TL
Department of Clinical Pathology, Tuen Mun Hospital, Hong Kong SAR.
D000123:Acetyltransferases / Q000235:genetics; D000328:Adult; D000483:Alleles; D000617:Aminoglycosides / Q000494:pharmacology*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015373:Bacterial Typing Techniques; D002648:Child; D002675:Child, Preschool; D016000:Cluster Analysis; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D024881:Drug Resistance, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000382:microbiology* / Q000662:veterinary*; D029968:Escherichia coli Proteins / Q000235:genetics; D005260:Female; D005798:Genes, Bacterial; D014644:Genetic Variation; D006723:Hong Kong; D006801:Humans; D010957:Plasmids; D017422:Sequence Analysis, DNA
D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; D000123:Acetyltransferases; C019681:aminoglycoside acetyltransferase