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Suppressor system in Bacillus subtilis 168.

C P Georgopoulos
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Abstract

Multiple auxotrophic strains of Bacillus subtilis 168 were tested for joint one-step reversion of two or more auxotrophic markers to the wild-type phenotype. Mu8u5u5, a strain requiring leucine, methionine, and threonine, yielded revertants that grew without added methionine or threonine and proved to have a suppressor gene. When transferred by transformation with deoxyribonucleic acid, this suppressor gene also suppressed the adenine mutation in another strain, Mu8u5u6. The one-step double revertants fell into two distinct classes: strains of class su(+) (I) grow well in broth; strains of class su(+) (II) grow poorly. Strains su(+) (II) tend to revert frequently to the su(+) (I) or su(-) state. Conditional lethal mutants of phage phie were isolated which can grow on the su(+) and not on the su(-) strains.

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Bacillus subtilisBacteriophagesGenesGenetics, MicrobialMethodsMutagensMutationSuppression, GeneticTransformation, GeneticJournal Article

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BibTeXRIS

C P Georgopoulos. 1969. Suppressor system in Bacillus subtilis 168.. https://doi.org/10.1128/jb.97.3.1397-1402.1969

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