2POO

THERMOSTABLE PHYTASE IN FULLY CALCIUM LOADED STATE

2POO の概要

• エントリーDOI: 10.2210/pdb2poo/pdb
• 分子名称: PROTEIN (PHYTASE), CALCIUM ION (3 entities in total)
• 機能のキーワード: thermostable phytase, calcium loaded state, hydrolase
• 由来する生物種: Bacillus amyloliquefaciens
• 細胞内の位置: Secreted: O66037
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 39249.25

構造登録者

Ha, N.-C.,Oh, B.-H. (登録日: 1999-04-16, 公開日: 2000-04-19, 最終更新日: 2023-12-27)

主引用文献

Ha, N.C.,Oh, B.C.,Shin, S.,Kim, H.J.,Oh, T.K.,Kim, Y.O.,Choi, K.Y.,Oh, B.H.
Crystal structures of a novel, thermostable phytase in partially and fully calcium-loaded states.
Nat.Struct.Biol., 7:147-153, 2000

PubMed Abstract: Phytases hydrolyze phytic acid to less phosphorylated myo-inositol derivatives and inorganic phosphate. A thermostable phytase is of great value in applications for improving phosphate and metal ion availability in animal feed, and thereby reducing phosphate pollution to the environment. Here, we report a new folding architecture of a six-bladed propeller for phosphatase activity revealed by the 2.1 A crystal structures of a novel, thermostable phytase determined in both the partially and fully Ca2+-loaded states. Binding of two calcium ions to high-affinity calcium binding sites results in a dramatic increase in thermostability (by as much as approximately 30 degrees C in melting temperature) by joining loop segments remote in the amino acid sequence. Binding of three additional calcium ions to low-affinity calcium binding sites at the top of the molecule turns on the catalytic activity of the enzyme by converting the highly negatively charged cleft into a favorable environment for the binding of phytate.

PubMed: 10655618
DOI: 10.1038/72421

実験手法

X-RAY DIFFRACTION (2.05 Å)