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. 1988 Nov;120(3):651–655. doi: 10.1093/genetics/120.3.651

Second-Site Revertants of Escherichia Coli Trp Repressor Mutants

L S Klig 1, D L Oxender 1, C Yanofsky 1
PMCID: PMC1203543  PMID: 3066681

Abstract

Second-site reversion studies were performed with five missense mutants with defects in the trp repressor of Escherichia coli. These mutants were altered throughout the gene. The same unidirectional mutagen used in the isolation of these mutants, hydroxylamine, was used in reversion studies, to increase the liklihood that the revertants obtained would have second-site changes. Most of the second-site revertants were found to have the same amino acid substitutions detected previously as superrepressor changes. These second-site revertant repressors were more active in vivo than their parental mutant repressors, in the presence or absence of exogenous tryptophan. Apparently superrepressor changes at many locations in this protein can act globally to increase the activity of mutant repressors.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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