The N-terminal capping propensities of the D-helix modulate the allosteric activation of the Escherichia coli cAMP receptor protein.

ABSTRACT: Transduction of biological signals at the molecular level involves the activation and/or inhibition of allosteric proteins. In the transcription factor cAMP receptor protein (CRP) from Escherichia coli, the allosteric activation, or apo-holo transition, involves rigid body motions of domains and structural rearrangements within the hinge region connecting the cAMP- and DNA-binding domains. During this apo-holo transition, residue 138 is converted as part of the elongated D-helix to the position of the N-terminal capping residue of a shorter D-helix. The goal of the current study is to elucidate the role of residue 138 in modulating the allostery between cAMP and DNA binding. By systematically mutating residue 138, we found that mutants with higher N-terminal capping propensities lead to in

SUBMITTER: Yu S 

PROVIDER: S-EPMC3501046 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature