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Repressor of phage 16-3 with altered binding specificity indicates spatial differences in repressor-operator complexes.

Szilamér Ferenczi·László Orosz·Péter P Papp
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Abstract

The C repressor protein of phage 16-3, which is required for establishing and maintaining lysogeny, recognizes structurally different operators which differ by 2 bp in the length of the spacer between the conserved palindromic sequences. A "rotationally flexible protein homodimers" model has been proposed in order to explain the conformational adaptivity of the 16-3 repressor. In this paper, we report on the isolation of a repressor mutant with altered binding specificity which was used to identify a residue-base pair contact and to monitor the spatial relationship of the recognition helix of C repressor to the contacting major groove of DNA within the two kinds of repressor-operator complexes. Our results indicate spatial differences at the interface which may reflect different docking arrangements in recognition of the structurally different operators by the 16-3 repressor.

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BacteriophagesBinding SitesLysogenyOperator Regions, GeneticProtein BindingProtein ConformationRepressor ProteinsSinorhizobium melilotiViral ProteinsJournal ArticleResearch Support, Non-U.S. Gov't

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Szilamér Ferenczi, László Orosz, Péter P Papp. 2006. Repressor of phage 16-3 with altered binding specificity indicates spatial differences in repressor-operator complexes.. https://doi.org/10.1128/jb.188.4.1663-1666.2006

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