Reference - Detail
|Title||Rapid mapping of conditional and auxotrophic mutations in Escherichia coli K-12.|
The approximate genetic map locations of auxotrophic and conditional lethal mutations of Escherichia coli can be rapidly determined with replica plating techniques. A set of patches of 15 streptomycin-sensitive (Str(S)) Hfr strains with points of origin distributed around the map is replica plated onto a recombinant-selective plate with a lawn of Str(R) cells which carry an unmapped mutation. The map interval defined by the Hfr points of origin which are closest to the mutant locus is seen by the presence or absence of heavy patches of recombinants produced by transfer of early wild-type genes from the Hfrs. An alternative method is to replicate patches of different mutant strains (100 per plate) onto Hfr lawns; in this case more than 1,000 different mutants can be mapped in a single experiment in a few days. In this way, many types of mutations with similar phenotypes can be grouped as to approximate location on the genetic map. For ordering mutations within groups, the same replica plating methods can be used to cross F-prime derivatives of mutants with other mutants of the same group. Relative merits of these and other mapping methods of E. coli are discussed.
|MeSH||Chromosome Mapping* Chromosomes, Bacterial* Conjugation, Genetic Drug Resistance, Microbial Escherichia coli / drug effects Escherichia coli / growth & development* Escherichia coli / radiation effects Genetic Complementation Test Genetic Linkage Genetic Techniques* Methods Mutation* Phenotype Radiation Effects Recombination, Genetic Streptomycin / pharmacology Transduction, Genetic Ultraviolet Rays|
|Prokaryotes E. coli||JE7023 JE5984 JE5855 JE5554 ME8551 ME8556 ME8557 ME8562 ME8558 ME8561 ME8564 ME8559 ME8553 ME7260|