Interaction of mutant lambda repressors with operator and non-operator DNA.

H C Nelson; R T Sauer

doi:10.1016/0022-2836(86)90461-4

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Interaction of mutant lambda repressors with operator and non-operator DNA.

H C Nelson·R T Sauer

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Abstract

We have described a set of mutations that alter side-chains on the operator binding surface of lambda repressor. In this paper, we study the interactions of 12 purified mutant repressors with operator and non-operator DNA. The mutant proteins have operator affinities that are reduced from tenfold to greater than 10,000-fold compared to wild-type. Nine of the mutants have affinities for non-operator DNA that are similar to wild-type, two mutants show decreased non-specific binding, and one mutant has increased affinity for non-operator DNA. We discuss these findings in terms of the structural and energetic contributions of side-chain--DNA interactions, and show that certain contacts between the repressor and the operator backbone contribute both energy and specificity to the interaction.

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Amino Acid Sequence Bacteriophage lambda Computer Graphics Computer Simulation DNA, Viral DNA-Binding Proteins Escherichia coli Methylation Models, Genetic Mutation Operator Regions, Genetic Repressor Proteins Transcription Factors Viral Proteins Viral Regulatory and Accessory Proteins Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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H C Nelson, R T Sauer. 1986-11-05. Interaction of mutant lambda repressors with operator and non-operator DNA.. https://doi.org/10.1016/0022-2836(86)90461-4

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