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Trp holorepressor-trp operator interaction studied by protein distribution analysis.

P V Haydock·R L Somerville
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Abstract

Trp repressor protein of Escherichia coli (Mr 24,700) undergoes a conformational change upon interaction with L-tryptophan that enables the resulting binary complex to bind with high specificity to several operator targets in double-stranded DNA. By protein distribution analysis it was shown that a significant fraction of Trp repressor is inert in operator binding. The equilibrium dissociation constant for Trp holorepressor-Trp operator interaction is 6.7 nM at 20 degrees in 0.05M NaCl, pH 7.4. The Trp holorepressor-trp operator complex consists of one molecule of each of the participating species, even at high molar ratios of protein to DNA.

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Bacterial ProteinsEscherichia coliKineticsMathematicsMethodsOperonProtein ConformationRepressor ProteinsTranscription FactorsTryptophanEscherichia coli ProteinsJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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P V Haydock, R L Somerville. 1984-03-30. Trp holorepressor-trp operator interaction studied by protein distribution analysis.. https://doi.org/10.1016/0006-291x(84)90862-3

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