Sandbox Reserved 702: Difference between revisions

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The second magnesium ion, that is coordinated with the oxygens of the phosphates of ATP, facilitates the bond breakage between α and β-phosphates. Indeed, it stabilizes the resulting negative charges. The stabilisation of the negative charged intermediate is also performed by different positive charged residues: arginine 329, lysine 353, lysine 372 and lysine 346.

The products, pysophosphate and cyclic AMP dissociate through different solvent accessible channels. ~~It does not require the exposure of the active site~~ to the ~~solvent. However, the magnesium ions cal buid~~ electrostatic interactions with the ~~products and thus impair their dissociation~~. The binding of a water molecule to the ions is competitive with thier binding to reaction products and breaks the ~~electrostatis~~ links. ~~That is why it is~~ important ~~that~~ the ~~solvant has access to~~ the active site.

The products, pysophosphate and cyclic AMP dissociate through different solvent accessible channels in a two-step process facilitated by product protonation. They are linked to the enzyme by electrostatic interactions with the magnesium ions. The binding of a water molecule to the ions is competitive with thier binding to reaction products and breaks the electrostatic links. Ligands are progressively solvated. In a first time the most important electrostatic interactions are preserved. This depends on the flexibility of the active site. Then the electrostatic interactions are broken and the products can diffuse into solvent.

Sandbox Reserved 702: Difference between revisions

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Revision as of 19:51, 5 January 2013 view source Charlotte Kern (talk \| contribs) 157 edits No edit summary ← Older edit		Revision as of 20:03, 5 January 2013 view source Charlotte Kern (talk \| contribs) 157 edits No edit summary Newer edit →
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	The second magnesium ion, that is coordinated with the oxygens of the phosphates of ATP, facilitates the bond breakage between α and β-phosphates. Indeed, it stabilizes the resulting negative charges. The stabilisation of the negative charged intermediate is also performed by different positive charged residues: arginine 329, lysine 353, lysine 372 and lysine 346.		The second magnesium ion, that is coordinated with the oxygens of the phosphates of ATP, facilitates the bond breakage between α and β-phosphates. Indeed, it stabilizes the resulting negative charges. The stabilisation of the negative charged intermediate is also performed by different positive charged residues: arginine 329, lysine 353, lysine 372 and lysine 346.

	The products, pysophosphate and cyclic AMP dissociate through different solvent accessible channels. ~~It does not require the exposure of the active site~~ to the ~~solvent. However, the magnesium ions cal buid~~ electrostatic interactions with the ~~products and thus impair their dissociation~~. The binding of a water molecule to the ions is competitive with thier binding to reaction products and breaks the ~~electrostatis~~ links. ~~That is why it is~~ important ~~that~~ the ~~solvant has access to~~ the active site.		The products, pysophosphate and cyclic AMP dissociate through different solvent accessible channels in a two-step process facilitated by product protonation. They are linked to the enzyme by electrostatic interactions with the magnesium ions. The binding of a water molecule to the ions is competitive with thier binding to reaction products and breaks the electrostatic links. Ligands are progressively solvated. In a first time the most important electrostatic interactions are preserved. This depends on the flexibility of the active site. Then the electrostatic interactions are broken and the products can diffuse into solvent.