• Citations Per Year
Learn More
The dihydrofolate reductase structural gene, folA, has been closed into the multicopy vector pBR322 following the gene's enrichment by bacteriophage Mu-mediated transposition. Strains carrying the resultant plasmid, pJFM8, produce 25 to 30 times more dihydrofolate reductase than control strains. Consequently they are resistant to trimethoprim, an inhibitor(More)
Three recombinant plasmids have been studied which collectively carry all the nine known genes of the enterochelin system of iron transport in Escherichia coli K-12. The genetic organization of these genes was studied using a combination of Tn5 mutagenesis, subcloning of restriction fragments and restriction mapping. The order of the genes was established(More)
Transposition of chromosomal genes using bacteriophage Mu has been used to obtain a partial order of the nine closely linked genes of the enterochelin-dependent iron transport system of Escherichia coli K-12. Fragments of the ent gene cluster were transposed into the conjugative plasmid RP4 and were characterized by genetic complementation. The partial gene(More)
  • 1