1AF6

MALTOPORIN SUCROSE COMPLEX

1AF6 の概要

• エントリーDOI: 10.2210/pdb1af6/pdb
• 関連するBIRD辞書のPRD_ID: PRD_900003
• 分子名称: MALTOPORIN, beta-D-fructofuranose-(2-1)-alpha-D-glucopyranose, MAGNESIUM ION, ... (4 entities in total)
• 機能のキーワード: membrane protein, specific porin, beta barrel, sugar transport, sucrose
• 由来する生物種: Escherichia coli
• 細胞内の位置: Cell outer membrane; Multi-pass membrane protein: P02943
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 143401.47

構造登録者

Dutzler, R.,Schirmer, T. (登録日: 1997-03-21, 公開日: 1998-03-25, 最終更新日: 2024-10-30)

主引用文献

Wang, Y.F.,Dutzler, R.,Rizkallah, P.J.,Rosenbusch, J.P.,Schirmer, T.
Channel specificity: structural basis for sugar discrimination and differential flux rates in maltoporin.
J.Mol.Biol., 272:56-63, 1997

PubMed Abstract: Maltoporin (LamB) facilitates the diffusion of maltodextrins across the outer membrane of E. coli. The structural basis for the specificity of the channel is investigated by X-ray structure analysis of maltoporin in complex with the disaccharides sucrose, trehalose, and melibiose. The sucrose complex, determined to 2.4 A resolution, shows that the glucosyl moiety is partly inserted into the channel constriction, while the bulky fructosyl residue appears to be hindered to enter the constriction, thus interfering with its further translocation. One of the glucosyl moieties of trehalose is found in a similar position as the glucosyl moiety of sucrose, whereas melibiose appears disordered when bound to maltoporin. A comparison with the previously reported maltoporin-maltose complex sheds light on the basis for sugar discrimination, and explains the different permeation rates observed for the saccharides.

PubMed: 9299337
DOI: 10.1006/jmbi.1997.1224

実験手法

X-RAY DIFFRACTION (2.4 Å)