title: Novel host-vector system for selection and maintenance of plasmid-bearing, streptomycin-dependent Escherichia coli cells in antibiotic-free media.
abstract: A novel system for selection and maintenance of cells carrying a recombinant plasmid has been developed, using the streptomycin-dependent (Smd) Escherichia coli 4D host and a plasmid vector carrying an rpsL gene from an Sm-resistant (Smr) mutant of E. coli which masks the Smd phenotype. Strain 4D carrying the Smr pBR322 plasmid can grow without Sm. Using this host-vector system, we can select for cells carrying an Smr recombinant plasmid and maintain them in antibiotic-free media.
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D003001:Cloning, Molecular; D004352:Drug Resistance, Microbial; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics*; D029968:Escherichia coli Proteins; D005822:Genetic Vectors; D010957:Plasmids; D000091243:Ribosomal Protein S9; D012269:Ribosomal Proteins / Q000235:genetics; D012641:Selection, Genetic; D013307:Streptomycin / Q000494:pharmacology
chemical_list: D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D000091243:Ribosomal Protein S9; D012269:Ribosomal Proteins; C000717190:RpsI protein, E coli; C016700:ribosomal protein L7-L12; D013307:Streptomycin