Sandbox Reserved 1559: Difference between revisions
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== Structural highlights and structure-function relationships == | == Structural highlights and structure-function relationships == | ||
This protein has a <scene name='82/823083/6ojttriad/1'>Catalytic Triad</scene> which consists of the amino acids Phe-59, Tyr101, and Lys-134. These amino acids play an important role in catalysis for the protein. Lys-134 proved to be the most important amino acid. The basic spacefill view of the entire protein allows for visualization of the different elements in different colors. The elements shown are carbon (Grey), nitrogen (Blue), and oxygen (Red). The <scene name='82/823083/Spacefill/1'>spacefill view</scene> also allows for visualization of different allosteric binding sites. This protein has a <scene name='82/823083/Nsl_ligand/1'>ligand</scene>, called NSL. The structural fold of LsdA is that of a <scene name='83/830391/Rainbow_7blade_beta_propeller/2'>seven-bladed β-propeller | This protein has a <scene name='82/823083/6ojttriad/1'>Catalytic Triad</scene> which consists of the amino acids Phe-59, Tyr101, and Lys-134. These amino acids play an important role in catalysis for the protein. Lys-134 proved to be the most important amino acid. The basic spacefill view of the entire protein allows for visualization of the different elements in different colors. The elements shown are carbon (Grey), nitrogen (Blue), and oxygen (Red). The <scene name='82/823083/Spacefill/1'>spacefill view</scene> also allows for visualization of different allosteric binding sites. This protein has a <scene name='82/823083/Nsl_ligand/1'>ligand</scene>, called NSL. The structural fold of LsdA is that of a <scene name='83/830391/Rainbow_7blade_beta_propeller/2'>seven-bladed β-propeller</scene>. <scene name='82/823083/Hydrophobic/1'>Hydrophobic interactions</scene> are highlighted in grey, and polar regions are purple, while the ligand is yellow. This protein has a catalytic triad for binding that consists of tyrosine (hydrophilic), phenylalanine (hydrophobic), and lysine (has a positive charge). | ||
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The tertiary structure also creates a metal binding site of Histidines to keep the iron molecule in place. There have been two mechanisms proposed for Lsd's. In one mechanism, the hydroxystillbenoid is activated via the enzyme-catalyzed deprotonation of the 4-hydroxy group, which then allows electron delocalization toward an Fe3+. In the other mechanism, π electron density from the double bond is redistributed to the iron-oxy complex to form an Fe2+ cation intermediate. Deprotonation of the hydroxyl is demanding for both mechanisms and is assisted by Lys134 and Tyr101. | The tertiary structure also creates a <scene name='82/823083/Metal_binding_site/1'>metal-binding site</scene> of Histidines to keep the iron molecule in place. This site is located in the active site where the single Fe2+ ion resides at the center of the β-propeller. This metal ion is coordinated in a tetragonal pyramidal fashion by four histidines (His-167, His-218, His-282, and His-472). There have been two mechanisms proposed for Lsd's. In one mechanism, the hydroxystillbenoid is activated via the enzyme-catalyzed deprotonation of the 4-hydroxy group, which then allows electron delocalization toward an Fe3+. In the other mechanism, π electron density from the double bond is redistributed to the iron-oxy complex to form an Fe2+ cation intermediate. Deprotonation of the hydroxyl is demanding for both mechanisms and is assisted by Lys134 and Tyr101. | ||