3fwe is a 2 chain structure with sequence from Ecoli. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
[CRP_ECOLI] This protein complexes with cyclic AMP and binds to specific DNA sites near the promoter to regulate the transcription of several catabolite-sensitive operons. The protein induces a severe bend in the DNA. Acts as a negative regulator of its own synthesis as well as for adenylate cyclase (cyaA), which generates cAMP.[1]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
The binding of cAMP to the Escherichia coli catabolite gene activator protein (CAP) produces a conformational change that enables it to bind specific DNA sequences and regulate transcription, which it cannot do in the absence of the nucleotide. The crystal structures of the unliganded CAP containing a D138L mutation and the unliganded WT CAP were determined at 2.3 and 3.6 A resolution, respectively, and reveal that the two DNA binding domains have dimerized into one rigid body and their two DNA recognition helices become buried. The WT structure shows multiple orientations of this rigid body relative to the nucleotide binding domain supporting earlier biochemical data suggesting that the inactive form exists in an equilibrium among different conformations. Comparison of the structures of the liganded and unliganded CAP suggests that cAMP stabilizes the active DNA binding conformation of CAP through the interactions that the N(6) of the adenosine makes with the C-helices. These interactions are associated with the reorientation and elongation of the C-helices that precludes the formation of the inactive structure.
Structure of apo-CAP reveals that large conformational changes are necessary for DNA binding.,Sharma H, Yu S, Kong J, Wang J, Steitz TA Proc Natl Acad Sci U S A. 2009 Sep 29;106(39):16604-9. Epub 2009 Sep 16. PMID:19805344[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
↑Aiba H. Transcription of the Escherichia coli adenylate cyclase gene is negatively regulated by cAMP-cAMP receptor protein. J Biol Chem. 1985 Mar 10;260(5):3063-70. PMID:2982847
↑Sharma H, Yu S, Kong J, Wang J, Steitz TA. Structure of apo-CAP reveals that large conformational changes are necessary for DNA binding. Proc Natl Acad Sci U S A. 2009 Sep 29;106(39):16604-9. Epub 2009 Sep 16. PMID:19805344
