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PubMed · 795369

R plasmids in Streptococcus agalactiae (group B).

T Horodniceanu·D H Bouanchaud·G Bieth·Y A Chabbert
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Abstract

Two plasmids determining resistance to tetracycline (RIP500) and to chloramphenicol, erythromycin, lincomycin, and pristinamycin I (RIP501) were isolated from a strain of Streptococcus agalactiae. The frequency-of-resistance loss is very low for RIP500 (<3 x 10(4)) but higher for RIP501 (the efficiency was dependent upon the curing agents and incubation temperature and varied between 0.5 and 96%). Derivatives susceptible to all drugs were also obtained. RIP500 and RIP501 have similar molecular weights (17.9 x 10(6) and 20 x 10(6), respectively) and represent different percentages of total deoxyribonucleic acid (0.4 and 4%, respectively). The number of copies of RIP500 and RIP501 per cell is different, and these plasmids are likely replicated under different kinds of control (stringent and/or relaxed). No plasmid deoxyribonucleic acid was found in a derivative of strain B96 susceptible to all drugs.

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Centrifugation, Density GradientChloramphenicolDNA, BacterialDrug Resistance, MicrobialMolecular WeightPlasmidsR FactorsStreptococcus agalactiaeJournal Article

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T Horodniceanu, D H Bouanchaud, G Bieth, Y A Chabbert. 1976. R plasmids in Streptococcus agalactiae (group B).. https://doi.org/10.1128/aac.10.5.795

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