Probes for the study of mupirocin resistance in staphylococci.

Probes constructed from a 4.05-kb EcoRI digest fragment of a mupirocin resistance plasmid and a 751-bp internal part of this fragment hybridised with DNA from all of 36 independent high-level mupirocin-resistant staphylococci tested from seven centres; most were Staphylococcus aureus. In most instances the probes detected an EcoRI digest fragment of approximately 4 kb. Probes did not hybridise to DNA from low-level resistant strains, nor from strains sensitive to mupirocin.