1poo
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| , resolution 2.1Å | |||||||
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| Ligands: | |||||||
| Gene: | PHY (Bacillus amyloliquefaciens) | ||||||
| Activity: | 3-phytase, with EC number 3.1.3.8 | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
THERMOSTABLE PHYTASE FROM BACILLUS SP
OverviewOverview
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.
About this StructureAbout this Structure
1POO is a Single protein structure of sequence from Bacillus amyloliquefaciens. Full crystallographic information is available from OCA.
ReferenceReference
Crystal structures of a novel, thermostable phytase in partially and fully calcium-loaded states., Ha NC, Oh BC, Shin S, Kim HJ, Oh TK, Kim YO, Choi KY, Oh BH, Nat Struct Biol. 2000 Feb;7(2):147-53. PMID:10655618
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