3FWE

Crystal Structure of the Apo D138L CAP mutant

3FWE の概要

• エントリーDOI: 10.2210/pdb3fwe/pdb
• 分子名称: Catabolite gene activator, PROLINE (3 entities in total)
• 機能のキーワード: helix-turn-helix, transcription, camp, allostery, acetylation, activator, camp-binding, dna-binding, nucleotide-binding, transcription regulation, transcription regulator
• 由来する生物種: Escherichia coli K-12
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 47571.28

構造登録者

Sharma, H.,Wang, J.,Kong, J.,Yu, S.,Steitz, T. (登録日: 2009-01-17, 公開日: 2009-09-08, 最終更新日: 2024-02-21)

主引用文献

Sharma, H.,Yu, S.,Kong, J.,Wang, J.,Steitz, T.A.
Structure of apo-CAP reveals that large conformational changes are necessary for DNA binding
Proc.Natl.Acad.Sci.USA, 106:16604-16609, 2009

PubMed Abstract: 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.

PubMed: 19805344
DOI: 10.1073/pnas.0908380106

実験手法

X-RAY DIFFRACTION (2.3 Å)