1UN1

Xyloglucan endotransglycosylase native structure.

1UN1 の概要

• エントリーDOI: 10.2210/pdb1un1/pdb
• 関連するPDBエントリー: 1UMZ
• 分子名称: XYLOGLUCAN ENDOTRANSGLYCOSYLASE, beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, GOLD ION, ... (4 entities in total)
• 機能のキーワード: glycoside hydrolase, xet, xth, xeh, transglycosylation, xyloglucan, transferase, glycosyltransferase
• 由来する生物種: POPULUS TREMULA (EUROPEAN ASPEN)
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 66433.19

構造登録者

Johansson, P.,Brumer, H.,Kallas, A.,Henriksson, H.,Denman, S.,Teeri, T.T.,Jones, T.A. (登録日: 2003-09-03, 公開日: 2004-03-18, 最終更新日: 2024-11-20)

主引用文献

Johansson, P.,Brumer, H.,Baumann, M.,Kallas, A.,Henriksson, H.,Denman, S.,Teeri, T.T.,Jones, T.A.
Crystal Structures of a Poplar Xyloglucan Endotransglycosylase Reveal Details of Transglycosylation Acceptor Binding
Plant Cell, 16:874-, 2004

PubMed Abstract: Xyloglucan endotransglycosylases (XETs) cleave and religate xyloglucan polymers in plant cell walls via a transglycosylation mechanism. Thus, XET is a key enzyme in all plant processes that require cell wall remodeling. To provide a basis for detailed structure-function studies, the crystal structure of Populus tremula x tremuloides XET16A (PttXET16A), heterologously expressed in Pichia pastoris, has been determined at 1.8-A resolution. Even though the overall structure of PttXET16A is a curved beta-sandwich similar to other enzymes in the glycoside hydrolase family GH16, parts of its substrate binding cleft are more reminiscent of the distantly related family GH7. In addition, XET has a C-terminal extension that packs against the conserved core, providing an additional beta-strand and a short alpha-helix. The structure of XET in complex with a xyloglucan nonasaccharide, XLLG, reveals a very favorable acceptor binding site, which is a necessary but not sufficient prerequisite for transglycosylation. Biochemical data imply that the enzyme requires sugar residues in both acceptor and donor sites to properly orient the glycosidic bond relative to the catalytic residues.

PubMed: 15020748
DOI: 10.1105/TPC.020065

実験手法

X-RAY DIFFRACTION (2.1 Å)