title: [Tetracycline resistance in Haemophilus influenzae is plasmid-linked].
abstract: A strain of Haemophilus influenzae resistant to tetracycline (MIC 16-32 mug/ml) was "cured" of tetracycline resistance by ethidium bromide. DNA centrifugation in cesium chloride + ethidium bromide density gradients showed the existence of a band of non-chromosomal DNA molecules in the original resistant strain. This band was not found in lysates of a strain "cured" of tetracycline resistance by ethidium bromide. These facts support the hypothesis that in this strain of Haemohpilus influenzae, tetracycline resistance is plasmid mediated.
mesh_terms: D002499:Centrifugation, Density Gradient; D004269:DNA, Bacterial / Q000032:analysis; D004352:Drug Resistance, Microbial; D004996:Ethidium / Q000494:pharmacology; D005111:Extrachromosomal Inheritance; D006190:Haemophilus / Q000187:drug effects*; D010957:Plasmids / Q000187:drug effects; D013752:Tetracycline / Q000494:pharmacology*
chemical_list: D004269:DNA, Bacterial; D004996:Ethidium; D013752:Tetracycline
vernacular_title: Résistance plasmidique à la tétracycline chez Haemophilus influenzae