1Q1B

Crystal structure of E. coli MalK in the nucleotide-free form

1Q1B の概要

• エントリーDOI: 10.2210/pdb1q1b/pdb
• 関連するPDBエントリー: 1Q12 1Q1E
• 分子名称: Maltose/maltodextrin transport ATP-binding protein malK (1 entity in total)
• 機能のキーワード: nucleotide-free form, semi-open dimer, sugar transport, transport protein
• 由来する生物種: Escherichia coli
• 細胞内の位置: Cell inner membrane; Peripheral membrane protein: P68187
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 168970.28

構造登録者

Chen, J.,Lu, G.,Lin, J.,Davidson, A.L.,Quiocho, F.A. (登録日: 2003-07-18, 公開日: 2003-09-30, 最終更新日: 2024-02-14)

主引用文献

Chen, J.,Lu, G.,Lin, J.,Davidson, A.L.,Quiocho, F.A.
A tweezer-like motion of the ATP-binding cassette dimer in an ABC transport cycle
Mol.Cell, 12:651-661, 2003

PubMed Abstract: The ATPase components of ATP binding cassette (ABC) transporters power the transporters by binding and hydrolyzing ATP. Major conformational changes of an ATPase are revealed by crystal structures of MalK, the ATPase subunit of the maltose transporter from Escherichia coli, in three different dimeric configurations. While other nucleotide binding domains or subunits display low affinity for each other in the absence of the transmembrane segments, the MalK dimer is stabilized through interactions of the additional C-terminal domains. In the two nucleotide-free structures, the N-terminal nucleotide binding domains are separated to differing degrees, and the dimer is maintained through contacts of the C-terminal regulatory domains. In the ATP-bound form, the nucleotide binding domains make contact and two ATPs lie buried along the dimer interface. The two nucleotide binding domains of the dimer open and close like a pair of tweezers, suggesting a regulatory mechanism for ATPase activity that may be tightly coupled to translocation.

PubMed: 14527411
DOI: 10.1016/j.molcel.2003.08.004

実験手法

X-RAY DIFFRACTION (2.8 Å)