9UI2

Crystal structure of Thermus thermophilus HB8 transaldolase

9UI2 の概要

• エントリーDOI: 10.2210/pdb9ui2/pdb
• 分子名称: Probable transaldolase, SULFATE ION, 1,2-ETHANEDIOL, ... (4 entities in total)
• 機能のキーワード: nonulose, octulose, transaldolase, rare sugar, transferase
• 由来する生物種: Thermus thermophilus (strain ATCC 27634 / DSM 579 / HB8)
• タンパク質・核酸の鎖数: 10
• 化学式量合計: 265733.67

構造登録者

Kamitori, S. (登録日: 2025-04-15, 公開日: 2025-07-30, 最終更新日: 2025-08-06)

主引用文献

Yoshihara, A.,Miyoshi, E.,Tomino, S.,Hanaki, Y.,Mochizuki, S.,Yoshida, H.,Izumori, K.,Kamitori, S.
Synthetic Study of 8- and 9-Carbon Sugars by Transaldolase.
J.Agric.Food Chem., 73:18914-18922, 2025

PubMed Abstract: In nature, higher carbon sugars composed of 7 or more carbons exist in limited quantities. Since some higher carbon sugars have attracted attention due to their biological activities, it is necessary to develop a strategy to synthesize them. Transaldolase catalyzes the transfer of three-carbon units from d-fructose-6-phosphate (donor) to d-erythrulose-4-phosphate (acceptor) to produce d-sedoheptulose-7-phosphate. If transaldolase can recognize nonphosphorylated monosaccharides as substrates, it can synthesize 8-carbon octuloses and 9-carbon nonuloses using nonphosphorylated pentoses and hexoses as acceptors, respectively. We performed biochemical and structural characterization of thermophilic HB8 transaldolase and successfully synthesized octuloses and nonuloses using nonphosphorylated aldoses as acceptors: d-ribose (conversion rate of 74%), d-xylose (55%), l-arabinose (49%), l-lyxose (84%), d-allose (13%), d-galactose (56%), and l-altrose (71%). Products were identified by LC/MS and NMR spectroscopic analyses. X-ray structure of the enzyme showed that the wide and hydrophilic catalytic site facilitates the binding of nonphosphorylated aldoses as acceptors.

PubMed: 40668734
DOI: 10.1021/acs.jafc.5c05539

実験手法

X-RAY DIFFRACTION (1.7 Å)