3AMS

Crystal Structures of Bacillus subtilis Alkaline Phytase in Complex with Ca2+, Cd2+, Co2+, Ni2+, Mg2+ and myo-Inositol Hexasulfate

3AMS の概要

• エントリーDOI: 10.2210/pdb3ams/pdb
• 関連するPDBエントリー: 3AMR
• 分子名称: 3-phytase, D-MYO-INOSITOL-HEXASULPHATE, CALCIUM ION, ... (5 entities in total)
• 機能のキーワード: beta-propeller, phytase, phytate, myo-inositol hexasulfate, hydrolase-hydrolase inhibitor complex, hydrolase/hydrolase inhibitor
• 由来する生物種: Bacillus subtilis
• 細胞内の位置: Secreted: O31097
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 40738.77

構造登録者

Zeng, Y.F.,Ko, T.P.,Lai, H.L.,Cheng, Y.S.,Wu, T.H.,Ma, Y.,Yang, C.S.,Cheng, K.J.,Huang, C.H.,Guo, R.T.,Liu, J.R. (登録日: 2010-08-22, 公開日: 2011-04-13, 最終更新日: 2023-11-01)

主引用文献

Zeng, Y.F.,Ko, T.P.,Lai, H.L.,Cheng, Y.S.,Wu, T.H.,Ma, Y.,Chen, C.C.,Yang, C.S.,Cheng, K.J.,Huang, C.H.,Guo, R.T.,Liu, J.R.
Crystal structures of Bacillus alkaline phytase in complex with divalent metal ions and inositol hexasulfate
J.Mol.Biol., 409:214-224, 2011

PubMed Abstract: Alkaline phytases from Bacillus species, which hydrolyze phytate to less phosphorylated myo-inositols and inorganic phosphate, have great potential as additives to animal feed. The thermostability and neutral optimum pH of Bacillus phytase are attributed largely to the presence of calcium ions. Nonetheless, no report has demonstrated directly how the metal ions coordinate phytase and its substrate to facilitate the catalytic reaction. In this study, the interactions between a phytate analog (myo-inositol hexasulfate) and divalent metal ions in Bacillus subtilis phytase were revealed by the crystal structure at 1.25 Å resolution. We found all, except the first, sulfates on the substrate analog have direct or indirect interactions with amino acid residues in the enzyme active site. The structures also unraveled two active site-associated metal ions that were not explored in earlier studies. Significantly, one metal ion could be crucial to substrate binding. In addition, binding of the fourth sulfate of the substrate analog to the active site appears to be stronger than that of the others. These results indicate that alkaline phytase starts by cleaving the fourth phosphate, instead of the third or the sixth that were proposed earlier. Our high-resolution, structural representation of Bacillus phytase in complex with a substrate analog and divalent metal ions provides new insight into the catalytic mechanism of alkaline phytases in general.

PubMed: 21463636
DOI: 10.1016/j.jmb.2011.03.063

実験手法

X-RAY DIFFRACTION (2.08 Å)