Sandbox Reserved 714: Difference between revisions

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Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA, Fabien Dutreux, Anna Bonhoure

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 /10-phosphonoxy-hydroxy-octadecanoate + H<sub>2</sub>O ↔ 9/10-dihydroxy-octadecanoate + phosphate
-Its <scene name='Sandbox_Reserved_714/Nter_activesite/1'>active site</scene> contains several conserved aspartates in phosphatases and phosphonatases (belonging to the family of haloacid dehalogenase): D9, D11, D184 and D185. This enzymatic activity is Mg<sup>2+</sup> dependant, because the structure of the active site is in its optimal conformation when the cation makes coordination interactions. When the catalytic activity of the N-term domain is available, Magnesium is octahedrally coordinated with the four aspartates, one water molecule and the phosphate belonging to the substrate. We can note that Mg<sup>2+</sup> is not directly involved in the catalytic mechanism, and all its interactions with the active site remain during the hydrolysis. Its single role consists in maintaining the three-dimensional structure of the active site.
+Its <scene name='Sandbox_Reserved_714/Nter_activesite/1'>active site</scene> contains several conserved aspartates in phosphatases and phosphonatases: D9, D11, D184 and D185. This enzymatic activity is Mg<sup>2+</sup> dependant, because the structure of the active site is in its optimal conformation when the cation makes coordination interactions. When the catalytic activity of the N-term domain is available, Magnesium is octahedrally coordinated with the four aspartates, one water molecule and the phosphate belonging to the substrate. We can note that Mg<sup>2+</sup> is not directly involved in the catalytic mechanism, and all its interactions with the active site remain during the hydrolysis. Its single role consists in maintaining the three-dimensional structure of the active site.
 First, the oxygen on the lateral chain of D9 attacks the phosphate. After the addition of a proton H<sub>+</sub>, the product with its two hydroxyl functions is released, while the phosphate is still linked to D9. Then, a waters molecule binds the phosphate, breaking its bond with the aspartate. Therefore the phosphate can be finally released and the active site can accept a lipid again and start a new catalytic cycle.