ISSN:
1432-072X
Keywords:
Methanobacterium thermoautotrophicum
;
Archaebacteria
;
Methanogenic bacteria
;
Mutagenesis
;
Auxotrophic mutants
;
N-methyl-N′-nitro-N-nitrosoguanidine
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The death rate ofMethanobacterium thermoautotrophicum strain Marburg upon exposure toN-methyl-N′-nitro-N-nitrosoguanidine under anaerobic conditions was of the same order of magnitude as the death rates that have been reported forEscherichia coli. Cultures of the methanogenic bacterium, mutagenized by nitrosoguanidine-treatment and grown under non-selective conditions, yielded mutants resistant toDL-ethionine (30 mM) or to 2-bromoethane sulfonic acid (3.8 mM). No mutants were observed in untreated controls. Among 1500 clones obtained from nitrosoguanidine-treated cell suspensions there were 6 mutants requiring a single growth factor each, namelyl-leucine,l-phenylalanine, thiamine (2 mutants) or adenosine (2 mutants). Three mutant-strains were studied in more detail. They were genetically stable (no revertants among 109 cells), and wild type growth rates were restored by 5 mml-leucine, 0.4 mM adenosine and 0.03 mM thiamine, respectively.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00692718
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