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Interaction of bacteriophage lambda repressor with nonoperator DNA containing single-strand gaps.

R Sussman·J Resnick·K Calame·J Baluch
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Abstract

In direct binding assays, purified lambdaind+ repressor displayed high affinity for nonoperator DNA containing single-strand gaps. Its affinity for this same DNA but completely double-stranded, nicked, or denatured was considerably lower. In contrast, purified lambdaind- repressor had 1/10th the affinity for the gapped DNA, a level comparable to that of purified lac repressor. In the presence of limiting amounts of ind+ repressor, nonoperator DNA containing gaps could be shown to compete effectively with lambda DNA for binding of repressor. A previous model of lambda induction [Sussman, R. & Ben-Zeev, H. (1975) Proc. Natl. Acad. Sci. USA 72, 1973--1976], based on the assumption that this phenomenon involves the binding of repressor to lesions in the host DNA, is reevaluated in the light of the data reported here.

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Binding SitesBinding, CompetitiveColiphagesDNA, Single-StrandedGenes, RegulatorLysogenyProtein BindingRepressor ProteinsStructure-Activity RelationshipTranscription FactorsVirus ReplicationJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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R Sussman, J Resnick, K Calame, J Baluch. 1978. Interaction of bacteriophage lambda repressor with nonoperator DNA containing single-strand gaps.. https://doi.org/10.1073/pnas.75.12.5817

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