Sandbox Reserved 714: Difference between revisions

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The N-terminal domain has specific features that facilitate the binding of a lipid substrate. There are <scene name='Sandbox_Reserved_714/Nter_cleft-tunnel-activesite/2'>three sites</scene> that ensure the proper positioning of the substrate. First, a hydrophobic cleft of about 25 Å long is situated near the N-term core so that one of the two ends of the aliphatic substrate is near the interface between the two domains N-term and C-term (proline-rich linker). Secondly, a hydrophobic tunnel (about 14 Å long) binds the aliphatic chain of the substrate and allows the second end to be in the active site. The active site is a negatively charged pocket of about 15 Å deep, and contains a Mg<sup>2+</sup> cation necessary to the catalytic function.

The aminoacids which are involved in the active site of the N-term domain are the Asp9, Asp11 and Asp185 basic aminoacids which can bind with a Mg2+ ion each, which is necessary to permit the substrate binding. There is also a modified lysine, the Lys43, which has an acetyl group on its N6.

The aminoacids which are involved in the active site of the C-term domain can be divided in two groups : the binding aminoacids and the catalytic aminoacids.

The His239, Tyr241, Arg249 and Glu298 are involved in the binding of the substrate, the Hexaethylene Glycol (P6G).

The Asp 335, Asp496, Tyr 466 and His 524 are the catalytic aminoacids of the active site. Asp 335 can lead nucleophilic additions, Tyr 466 is a proton donor and His 524 is a proton acceptor.

Sandbox Reserved 714: Difference between revisions

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 The N-terminal domain has specific features that facilitate the binding of a lipid substrate. There are <scene name='Sandbox_Reserved_714/Nter_cleft-tunnel-activesite/2'>three sites</scene> that ensure the proper positioning of the substrate. First, a hydrophobic cleft of about 25 Å long is situated near the N-term core so that one of the two ends of the aliphatic substrate is near the interface between the two domains N-term and C-term (proline-rich linker). Secondly, a hydrophobic tunnel (about 14 Å long) binds the aliphatic chain of the substrate and allows the second end to be in the active site. The active site is a negatively charged pocket of about 15 Å deep, and contains a Mg<sup>2+</sup> cation necessary to the catalytic function.
+The aminoacids which are involved in the active site of the N-term domain are the Asp9, Asp11 and Asp185 basic aminoacids which can bind with a Mg2+ ion each, which is necessary to permit the substrate binding. There is also a modified lysine, the Lys43, which has an acetyl group on its N6.
+The aminoacids which are involved in the active site of the C-term domain can be divided in two groups : the binding aminoacids and the catalytic aminoacids.
+The His239, Tyr241, Arg249 and Glu298 are involved in the binding of the substrate, the Hexaethylene Glycol (P6G).
+The Asp 335, Asp496, Tyr 466 and His 524 are the catalytic aminoacids of the active site. Asp 335 can lead nucleophilic additions, Tyr 466 is a proton donor and His 524 is a proton acceptor.