3UGG

Crystal structure of a 6-SST/6-SFT from Pachysandra terminalis in complex with 1-kestose

3UGG の概要

• エントリーDOI: 10.2210/pdb3ugg/pdb
• 関連するPDBエントリー: 3UGF 3UGH
• 関連するBIRD辞書のPRD_ID: PRD_900029
• 分子名称: Sucrose:(Sucrose/fructan) 6-fructosyltransferase, alpha-L-fucopyranose-(1-3)-2-acetamido-2-deoxy-beta-D-glucopyranose, beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-[alpha-L-fucopyranose-(1-3)]2-acetamido-2-deoxy-beta-D-glucopyranose, ... (9 entities in total)
• 機能のキーワード: fructosyltransferase, glycoside hydrolase family 32, transferase
• 由来する生物種: Pachysandra terminalis
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 128858.20

構造登録者

Lammens, W.,Rabijns, A.,Van Laere, A.,Strelkov, S.V.,Van den Ende, W. (登録日: 2011-11-02, 公開日: 2011-11-30, 最終更新日: 2024-10-09)

主引用文献

Lammens, W.,Le Roy, K.,Yuan, S.,Vergauwen, R.,Rabijns, A.,Van Laere, A.,Strelkov, S.V.,Van den Ende, W.
Crystal structure of 6-SST/6-SFT from Pachysandra terminalis, a plant fructan biosynthesizing enzyme in complex with its acceptor substrate 6-kestose.
Plant J., 70:205-219, 2012

PubMed Abstract: Fructans play important roles as reserve carbohydrates and stress protectants in plants, and additionally serve as prebiotics with emerging antioxidant properties. Various fructan types are synthesized by an array of plant fructosyltransferases belonging to family 32 of the glycoside hydrolases (GH32), clustering together with GH68 in Clan-J. Here, the 3D structure of a plant fructosyltransferase from a native source, the Pachysandra terminalis 6-SST/6-SFT (Pt6-SST/6-SFT), is reported. In addition to its 1-SST (1-kestose-forming) and hydrolytic side activities, the enzyme uses sucrose to create graminan- and levan-type fructans, which are probably associated with cold tolerance in this species. Furthermore, a Pt6-SST/6-SFT complex with 6-kestose was generated, representing a genuine acceptor binding modus at the +1, +2 and +3 subsites in the active site. The enzyme shows a unique configuration in the vicinity of its active site, including a unique D/Q couple located at the +1 subsite that plays a dual role in donor and acceptor substrate binding. Furthermore, it shows a unique orientation of some hydrophobic residues, probably contributing to its specific functionality. A model is presented showing formation of a β(2-6) fructosyl linkage on 6-kestose to create 6,6-nystose, a mechanism that differs from the creation of a β(2-1) fructosyl linkage on sucrose to produce 1-kestose. The structures shed light on the evolution of plant fructosyltransferases from their vacuolar invertase ancestors, and contribute to further understanding of the complex structure-function relationships within plant GH32 members.

PubMed: 22098191
DOI: 10.1111/j.1365-313X.2011.04858.x

実験手法

X-RAY DIFFRACTION (2.9 Å)