PMID:16562043

From omp dev
Jump to: navigation, search
Citation

Eriksson-Grennberg, KG, Boman, HG, Jansson, JA and Thorén, S (1965) Resistance of Escherichia coli to Penicillins I. Genetic Study of Some Ampicillin-Resistant Mutants.J. Bacteriol. 90:54-62

Abstract

Eriksson-Grennberg, Kerstin G. (University of Uppsala, Uppsala, Sweden), Hans G. Boman, J. A. Torbjörn Jansson, and Sone Thorén. Resistance of Escherichia coli to penicillins. I. Genetic study of some ampicillin-resistant mutants. J. Bacteriol. 90:54-62. 1965.-A number of ampicillin-resistant mutants have been isolated and characterized. Of these strains, two groups have been genetically investigated: members of one group, which are moderately resistant to ampicillin (Amp(r) (10)) carry mutations in a locus which we have designated ampA; another strain, which is resistant to high levels (50 mug/ml) of ampicillin, is a multistep mutant for which a genotype cannot yet be written. The phenotype of this strain has been designated Amp(r) (50). The location of ampA was studied by the interrupted-conjugation technique, with argF, metB, mtl, and serA as reference markers. The phenotypic expression was the same for ampA and argF. These experiments, as well as recombination without selection for ampicillin resistance, indicate that ampA is located between argF and pyrB. "Broken slopes" on the recombinant curves and failure to demonstrate cotransduction make a more accurate mapping difficult. Phage P1bt transduced ampA from resistant donors to sensitive recipient strains with a frequency of 5 x 10(-7). The ampA locus segregated in conjugation and transduction experiments with an Amp(r) (50) donor strain, but neither method gave a genetic transfer of high resistance to ampicillin. Penicillinase activity was demonstrated in two independent mutants carrying the ampA locus.

Links

PubMed

Keywords


Main Points of the Paper

Please summarize the main points of the paper.

Materials and Methods Used

Please list the materials and methods used in this paper (strains, plasmids, antibodies, etc).

Phenotype Annotations

See Help:AnnotationTable for details on how to edit this table.
<protect>

Phenotype of Taxon Information Genotype Information (if known) Condition Information OMP ID OMP Term Name ECO ID ECO Term Name Notes Status

</protect>

Notes

References

See Help:References for how to manage references in omp dev.