1887

Abstract

SUMMARY: Competitive hybridization was used to detect the deletion of chromosomal DNA accompanying the loss of resistance to methicillin (and concomitantly, to cadmium, mercury and tetracycline) from a clinical strain of methicillin-resistant (MRSA). The method was also used to screen a partial plasmid library of chromosomal III fragments from the MRSA strain. Eight recombinant plasmid clones were identified as containing DNA included in the deletion. These clones were used as probes to screen a phage library of the total DNA of the same MRSA strain, resulting in the isolation of overlapping recombinant phage clones carrying 24 kb of the deleted DNA. Two of the cloned III fragments were associated closely with methicillin resistance, as shown by probing DNA from an independent methicillin-sensitive/resistant transduced strain pair and from two MRSA strains following growth in the presence of high concentrations of methicillin. The endonuclease map of the cloned DNA indicates the presence of four copies of a direct repeat less than 1 kb in size. The map is also consistent with the presence in the chromosome of sequences for mercury resistance () and for the tetracycline-resistance plasmid pT 181.

Loading

Article metrics loading...

/content/journal/micro/10.1099/00221287-133-7-1919
1987-07-01
2024-10-03
Loading full text...

Full text loading...

/content/journal/micro/10.1099/00221287-133-7-1919
Loading
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error