1qlg: Difference between revisions
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==Overview== | ==Overview== | ||
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 . | 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 Structure== | ==About this Structure== | ||
1QLG is a | 1QLG is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_amyloliquefaciens Bacillus amyloliquefaciens] with CA and MG as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/3-phytase 3-phytase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.3.8 3.1.3.8] Structure known Active Site: MG. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1QLG OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: thermostable]] | [[Category: thermostable]] | ||
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