Physical studies of a plasmid mediating tetracycline resistance and hydrogen sulfide production inEscherichia coli

✍ Scribed by D. H. Bouanchaud; R. Hellio; Gilda Bieth; G. H. Stoleru

• Publisher: Springer
• Year: 1975
• Tongue: English
• Weight: 352 KB
• Volume: 140
• Category: Article
• ISSN: 1617-4615
• DOI: 10.1007/bf00267326

✦ Synopsis

Tetracycline resistance and hydrogen sulfide production have been previously found to be plasmid-mediated in a naturally-occurring strain of Escherichia coli; both functions are specified by a single conjugative plasmid called pIP231(Te-H2S); pIP231DNA was isolated as covalently closed molecules in dye-buoyant density gradients. The base ratio of the DNA was found to be 50% GC by density gradient analysis. Electron micrographs of plasmid molecules showed a contour length of 20 +/- 2 mum (40 +/- 4 X 10(6) daltons). Between one and two copies of pIP231 molecules per host chromosome were found in E. coli K12.