1LDA

CRYSTAL STRUCTURE OF THE E. COLI GLYCEROL FACILITATOR (GLPF) WITHOUT SUBSTRATE GLYCEROL

1LDA の概要

• エントリーDOI: 10.2210/pdb1lda/pdb
• 関連するPDBエントリー: 1LDF 1LDI
• 分子名称: Glycerol uptake facilitator protein, octyl beta-D-glucopyranoside (3 entities in total)
• 機能のキーワード: glycerol-conducting membrane channel protein, transport protein
• 由来する生物種: Escherichia coli
• 細胞内の位置: Cell inner membrane; Multi-pass membrane protein: P11244
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 30384.58

構造登録者

Nollert, P.,Miercke, L.J.W.,O'Connell, J.,Stroud, R.M. (登録日: 2002-04-08, 公開日: 2002-05-08, 最終更新日: 2023-08-16)

主引用文献

Tajkhorshid, E.,Nollert, P.,Jensen, M.O.,Miercke, L.J.,O'Connell, J.,Stroud, R.M.,Schulten, K.
Control of the selectivity of the aquaporin water channel family by global orientational tuning.
Science, 296:525-530, 2002

PubMed Abstract: Aquaporins are transmembrane channels found in cell membranes of all life forms. We examine their apparently paradoxical property, facilitation of efficient permeation of water while excluding protons, which is of critical importance to preserving the electrochemical potential across the cell membrane. We have determined the structure of the Escherichia coli aquaglyceroporin GlpF with bound water, in native (2.7 angstroms) and in W48F/F200T mutant (2.1 angstroms) forms, and carried out 12-nanosecond molecular dynamics simulations that define the spatial and temporal probability distribution and orientation of a single file of seven to nine water molecules inside the channel. Two conserved asparagines force a central water molecule to serve strictly as a hydrogen bond donor to its neighboring water molecules. Assisted by the electrostatic potential generated by two half-membrane spanning loops, this dictates opposite orientations of water molecules in the two halves of the channel, and thus prevents the formation of a "proton wire," while permitting rapid water diffusion. Both simulations and observations revealed a more regular distribution of channel water and an increased water permeability for the W48F/F200T mutant.

PubMed: 11964478
DOI: 10.1126/science.1067778

実験手法

X-RAY DIFFRACTION (2.8 Å)