title: Evidence that the multi-drug-resistance of Streptococcus faecalis BIO-4R is not carried by a plasmid.
abstract: The multi-drug-resistant strain Streptococcus faecalis BIO-4R was studied to see if it carried a plasmid responsible for antibiotic resistance. From results indicating that the antibiotic resistance of S. faecalis BIO-4R was not transferred to recipient bacteria, that the organism did not produce enzymes which inactivated antibiotics, and that the presence of covalently closed circular DNA was not demonstrated by dye-cesium chloride buoyant density gradient centrifugation, it was concluded that the organism did not carry such a plasmid. Studies on polyphenylalanine synthesis by cell-free extracts of the oganism showed that its ribosomes were resistant to chloramphenicol, tetracycline, streptomycin and kanamycin. These results, although rather indirectly, support the above notion that the multi-drug-resistance of S. faecalis BIO-4R is not mediated by a plasmid.
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002474:Cell-Free System; D002701:Chloramphenicol / Q000494:pharmacology; D003227:Conjugation, Genetic; D004352:Drug Resistance, Microbial; D013293:Enterococcus faecalis / Q000187:drug effects* / Q000378:metabolism; D004926:Escherichia coli / Q000187:drug effects; D010452:Peptide Biosynthesis; D011815:R Factors; D012270:Ribosomes / Q000187:drug effects / Q000378:metabolism; D013307:Streptomycin / Q000494:pharmacology; D013752:Tetracycline / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D002701:Chloramphenicol; D013752:Tetracycline; D013307:Streptomycin