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Plasmid-protein relaxation complexes in Staphylococcus aureus.

R Novick
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Abstract

Protein-deoxyribonucleic acid relaxation complexes have been demonstrated for six Staphylococcus aureus plasmids out of sixteen examined. Four of these encode stretomycin resistence, have molecular weights of about 2.7 x 10(6), and are isolated as supercoiled molecules that are virtally 100% relaxable by treatment with sodium dodecyl sulfate. It is probable that these four isolates represent a single widely disseminated plasmid species. The other two plasmids showing relaxation complexes have molecular weights of about 3 x 10(6) and encode chloramphenicol resistance. The complexes in these cases are unstable, and it has not been possible to induce more than 50% relaxation by any of the standard treatments. Ten other plasmids do not show detectable complexes. These include three penicillinase plasmids, four tetracycline-resistance plasmids, one plasmid carrying kanamycin-neomycin resistance, and finally, two chloramphenicol-resistance plasmids.

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Bacterial ProteinsChloramphenicolDNA, BacterialDrug Resistance, MicrobialExtrachromosomal InheritanceGlucoseMolecular WeightPlasmidsSodium ChlorideSodium Dodecyl SulfateStaphylococcus aureusStreptomycinJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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R Novick. 1976. Plasmid-protein relaxation complexes in Staphylococcus aureus.. https://doi.org/10.1128/jb.127.3.1177-1187.1976

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