Sandbox Reserved 1852: Difference between revisions
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[[Image:BindingPocket.png|300px|right|thumb|Figure 1. Active Site]] | [[Image:BindingPocket.png|300px|right|thumb|Figure 1. Active Site]] | ||
====Active Site==== | ====Active Site==== | ||
In the active state, there are <scene name='10/1075254/Active_site/3'>two catalytic residues</scene> that aim to stabilize the transition state of the Diels-Alder reaction. The Y134 acts as a <scene name='10/1075253/Y134_h_donation/1'>hydrogen bond donor</scene> to the oxygen on the <scene name='10/1075253/Ligand/6'>ligand</scene>. Q208 acts as a hydrogen bond acceptor to the nitrogen on the ligand. These interactions help reduce the energetic gap between orbitals allowing the reaction to proceed, outlined in HOMO/LUMO. | In the active state, there are <scene name='10/1075254/Active_site/3'>two catalytic residues</scene> that aim to stabilize the transition state of the Diels-Alder reaction. The Y134 acts as a <scene name='10/1075253/Y134_h_donation/1'>hydrogen bond donor</scene> to the oxygen on the <scene name='10/1075253/Ligand/6'>ligand</scene>. Q208 acts as a <scene name='10/1075253/208_bond_donor/1'>hydrogen bond acceptor</scene> to the nitrogen on the ligand. These interactions help reduce the energetic gap between orbitals allowing the reaction to proceed, outlined in HOMO/LUMO. | ||
====Helix Cap==== | ====Helix Cap==== | ||
In the evolution process, researchers added a 16-residue a-helix motif to the top of the binding site. The hydrophobic helix “functions as a lid to constrain the substrates in a productive orientation for reaction” (CITE), decreasing the Km of the enzyme and increasing the catalytic efficiency, as seen in the measured kinetics of the enzyme. | In the evolution process, researchers added a 16-residue a-helix motif to the top of the binding site. The hydrophobic helix “functions as a lid to constrain the substrates in a productive orientation for reaction” (CITE), decreasing the Km of the enzyme and increasing the catalytic efficiency, as seen in the measured kinetics of the enzyme. | ||
