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PubMed · 9268651

Quantitative specificity of the Mnt repressor.

D S Fields·Y He·A Y Al-Uzri·G D Stormo
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Abstract

The Mnt protein of Salmonella phage P22 binds site-specifically to its operator. To better understand this binding we used dideoxy DNA sequencing in a quantitative manner to determine the relative binding constants, and hence the relative free energies, of wild-type Mnt protein to a substantial number of variants of its operator. These measurements were supported by experiments which used the SELEX procedure to generate a set of operators from an initially randomized population. In the Discussion we show that the present model of Mnt protein/operator binding, due to Sauer and co-workers, along with the assumption of an independent contribution of each position in the operator to the total binding, provides a reasonably accurate description of the system. We also discuss the use of information content as a measure of DNA-protein binding specificity with the Mnt protein/operator system serving as an example and show again that the assumption of independence supports the current view of this case of site-specific binding.

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Bacteriophage P22Base SequenceBinding SitesConsensus SequenceDNADNA-Binding ProteinsKineticsLigandsMolecular Sequence DataOligodeoxyribonucleotidesRepressor ProteinsSalmonellaSequence AlignmentSubstrate SpecificityTemplates, GeneticThermodynamicsViral ProteinsViral Regulatory and Accessory ProteinsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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D S Fields, Y He, A Y Al-Uzri, G D Stormo. 1997-08-15. Quantitative specificity of the Mnt repressor.. https://doi.org/10.1006/jmbi.1997.1171

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