Cyclic AMP receptor protein interacts with lactose operator DNA

In vitro interaction of the Escherichia coli cyclic AMP receptor protein with the lactose repressor.

Sedimentation equilibrium studies show that the Escherichia coli cyclic AMP receptor protein (CAP) and lactose repressor associate to form a 2:1 complex in vitro. This is, to our knowledge, the first demonstration of a direct interaction of these proteins in the absence of DNA. No 1:1 complex was detected over a wide range of CAP concentrations, suggesting that binding is highly cooperative. Co...

Is DNA unwound by the cyclic AMP receptor protein?

Superhelical pBR 322 derivatives have been relaxed by eukaryotic topoisomerase I in the presence or in the absence of E. coli cyclic AMP receptor protein (CRP) and of cyclic AMP (cAMP). CRP alone, or cAMP alone do not affect the average linking number of the distribution of the relaxed topoisomers. Hence, they do not unwind the template. In the presence of cAMP, CRP induces a small unwinding. T...

Cyclic AMP Receptor Protein and RhaR

Analysis of Inducer and Operator Binding for Cyclic-AMP Receptor Protein Mutants

Allosteric transcription factors undergo binding events both at their inducer binding sites as well as at distinct DNA binding domains, and it is often difficult to disentangle the structural and functional consequences of these two classes of interactions. In this work, we compare the ability of two statistical mechanical models – the Monod-Wyman-Changeux (MWC) and the Koshland-Némethy-Filmer ...

Cyclic AMP-induced conformational change of cyclic AMP receptor protein (CRP): intragenic suppressors of cyclic AMP-independent CRP mutations.

We isolated and characterized crp mutations in Escherichia coli that allow cyclic AMP (cAMP) receptor protein to function without cAMP. These mutants defined a region involved in the cAMP-induced allosteric change of cAMP receptor protein that is necessary for activation of the protein. Currently, we have isolated intragenic suppressors of the crp mutations. These crp (Sup) mutants require cAMP...