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Opposite allosteric mechanisms in TetR and CAP.

ABSTRACT: Regulation of the DNA binding affinity of an oligomeric protein can be considered to consist of an intrinsic component, in which the affinity of an individual DNA-binding domain is modulated in response to effector binding, and an extrinsic component, in which the relative position of the protein's two DNA-binding domains are altered so that they can or cannot contact both half-site operators simultaneously. We demonstrated directly that the TetR repressor utilizes an extrinsic mechanism and CAP, the catabolite activator protein, utilizes an intrinsic mechanism.

SUBMITTER: Seedorff JE

PROVIDER: S-EPMC2762589 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature

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Opposite allosteric mechanisms in TetR and CAP.

Seedorff Jennifer E JE Rodgers Michael E ME Schleif Robert R

Protein science : a publication of the Protein Society 20090401 4

Regulation of the DNA binding affinity of an oligomeric protein can be considered to consist of an intrinsic component, in which the affinity of an individual DNA-binding domain is modulated in response to effector binding, and an extrinsic component, in which the relative position of the protein's two DNA-binding domains are altered so that they can or cannot contact both half-site operators simultaneously. We demonstrated directly that the TetR repressor utilizes an extrinsic mechanism and CAP ...[more]

PMID: 19309730

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