Interspecific co-transfer of antibiotic resistance plasmids in staphylococci in vivo.

The co-transfer of plasmid-borne genes governing resistance to gentamicin, tetracycline, erythromycin and chloramphenicol has been demonstrated on human and mouse skin. Two different gentamicin resistance plasmids have been studied in detail; both appear to have the ability to mobilize in vivo otherwise non-transferable resistance plasmids from coagulase-negative to coagulase-positive staphylococci. This emphasis the role of the skin in maintaining a pool of resistance genes available to pathogenic staphylococci.