- THIS ARTICLE
- Full Text (PDF)
- Alert me when this article is cited
- Alert me if a correction is posted
- SERVICES
- Similar articles in this journal
- Similar articles in PubMed
- Alert me to new issues of the journal
- Download to citation manager
- Reprints & Permissions
- CITING ARTICLES
- Citing Articles via HighWire
- Citing Articles via Google Scholar
- GOOGLE SCHOLAR
- Articles by Kingsman, A. J.
- Articles by Hulanicka, M. D.
- Search for Related Content
- PUBMED
- PubMed Citation
- Articles by Kingsman, A. J.
- Articles by Hulanicka, M. D.
GENETIC INSTABILITY IN AUXOTROPHS OF SALMONELLA TYPHIMURIUM REQUIRING CYSTEINE OR METHIONINE AND RESISTANT TO INHIBITION BY 1,2,4-TRIAZOLE
A. J. Kingsman 1, D. A. Smith 1, and M. D. Hulanicka 2
1 Department of Genetics, University of Birmingham, Birmingham,
England
2 Institute of Biochemistry and Biophysics, Polish Academy of
Sciences, 36 Rackowieka Street, Warsaw, Poland
Triazole-resistant (Trzr) derivatives of six cysteine- or methionine-requiring (Cym-) mutants of Salmonella typhimurium were isolated. Some of the derivatives of each mutant (CTS) were prototrophic, i.e., Cym- was suppressed. In every case suppression was initially unstable, Cym- auxotrophs being segregated at high frequency, although Trzr was stable. After several subcultures on selective medium, CTS strains were classified as either persistently unstable or stabilized. The unstable strains segregated Cym - auxotrophs at frequencies of 50–70%, whereas the stabilized strains segregated at frequencies of less than 1%. All suppressed strains had a stable Trzr marker co-transducible with cysA. However, there was a correlation between the class of CTS strain and Cym- phenotype. The stabilized strains were Cym+, whereas the unstable strains were Cym-. Acriflavin and ethidium bromide increased segregation in the unstable strains, suggesting the involvement of a plasmid. The stabilized strains were refractory to the curing agents. There was no detectable change in the quantity or quality of the S. typhimurium cryptic plasmid. The Trzr phenotype of the CTS strains suggested that Trzr mutations were of the stable TrzA type. It is suggested that correction of the Cym- lesions in CTS strains results from an insertion within the cysCDHIJ gene cluster of a DNA species originating in the cysALKptsHI region of the S. typhimurium chromosome.
Submitted on March 28, 1977Revised on February 10, 1978
This article has been cited by other articles:
 |
|
 |
|
  T. A. Seiflein and J. G. Lawrence Methionine-to-Cysteine Recycling in Klebsiella aerogenes J. Bacteriol., January 1, 2001; 183(1): 336 - 346. [Abstract] [Full Text]
|
|