Copper Resistance in Enterococcus faecium , Mediated by the tcrB Gene, Is Selected by Supplementation of Pig Feed with Copper Sulfate

Abstract

The tcr gene cluster mediates in vitro copper resistance in Enterococcus faecium. Here we describe the selection of tcr-mediated copper resistance in E. faecium in an animal feeding experiment with young pigs fed 175 mg copper/kg feed (ppm), which is the concentration commonly used for piglets in European pig production. tcr-mediated copper resistance was not selected for in a control group fed low levels of copper (6 ppm). We also show coselection of macrolide-and glycopeptide-resistant E. faecium in the animal group fed the high level of copper. Finally, we identify the tcr genes in the enterococcal species E. mundtii, E. casseliflavus, and E. gallinarum for the first time.

Antibiotic Resistance in the Environment, with Particular Reference to MRSA

“…The latter authors identified multiple antibiotic resistance genes from isolated plasmids. Some aspects of animal husbandry using heavy metal containing compounds select for antibiotic resistance genes in the environment, such an example being the use of copper growth supplements in pigs (Hasman et al, 2006). In Denmark glycopeptides were banned in food animal production in 1995, following that ban the rate of glycopeptide resistance in Enterococcus faecium (GRE) did not change.…”

“…GRE continue to be prevalent in Danish pigs, the explanation is now thought to be the linkage on the same plasmid of the copper resistance gene tcrB and macrolide/glycopeptide resistances. A feeding experiment using 175mg Cu/kg in feed selected for GRE in piglets, whereas 6mg/kg feed did not (Hasman et al, 2006).…”

Genotypes, Antibiogram, and Pulsed-Field Gel Electrophoresis Profiles of Escherichia Coli Strains from Piglets in Korea

“…However, excessive use of antibiotics has resulted in dissemination of antibiotic resistance in E. coli isolates. 1,9 Multiple antimicrobial resistances may arise from many different genetic determinants, and each may present specific epidemiological features. Therefore, determining antibiotic patterns would be useful in understanding and controlling ETEC infection in swine.…”

Effectiveness of antibacterial copper additives in silicone implants

“…Acquired bacterial copper resistance has been described for both Grampositive and Gram-negative organisms, 62,63 for example, Enterococcus faecium and E. faecalis isolated from humans. 63 The exact detection of adhering staphylococci and the necessary differentiation between dead and viable cells is given by the applied fluorescent staining technique.…”

“…Acquired bacterial copper resistance has been described for both Grampositive and Gram-negative organisms, 62,63 for example, Enterococcus faecium and E. faecalis isolated from humans. 63 The exact detection of adhering staphylococci and the necessary differentiation between dead and viable cells is given by the applied fluorescent staining technique. 64 The total amount of bacteria detected by BacLight staining showed significantly more adherent bacteria on the reference material than on the copperloaded silicone specimen without any significant difference between the differently coated specimens.…”