A spot test has been developed for detecting substances that enhance the transposition of Tn9 in Escherichia coli. Phage lambda::Tn9-infected cells were plated on chloramphenicol media and a drop of the test substance was placed at the center of the plate. Following incubation, chloramphenicol-resis
Isolation and mapping of Escherichia coli K12 mutants defective in Tn9 transposition
β Scribed by Hyina, T. S. ;Nechaeva, E. V. ;Romanova, Yu. M. ;Smirnov, G. B.
- Publisher
- Springer
- Year
- 1981
- Tongue
- English
- Weight
- 521 KB
- Volume
- 181
- Category
- Article
- ISSN
- 0026-8925
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β¦ Synopsis
Five mutants (called tnm) of Escherichia coli with impaired ability for transposition of Tn9 were isolated after treatment with ethyl methanesulfonate (EMS) or N-methyl-N'-nitro-N-nitrosoguanidine (NG). The map locations of the tnm mutations were determined by a combination of Hfr matings, F' episome complementation and P1 transductional mapping. The data obtained show that the five tnm mutations are located near 91 min on the Escherichia coli linkage map and are cotransducible with the metA marker with a frequency of 3%-4%. Introduction of F' plasmids containing this region complements the Tnm- phenotype for the two mutants tested i.e. tnm-1 and tnm-2 are recessive in tnm+/tnm- merodiploids.
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