Sandbox 39: Difference between revisions
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Specificity is controlled, however, by the <scene name='Sandbox_39/Active_site_revised/1'>catalytic diad</scene>, a hydrophobic pocket that accommodates the side chains of the protein substrate. This diad, shown above in red and clearly visible in the cleft of the enzyme, consists of cysteine25 (after which the protein is categorized as a cysteine protease)and histidine159. Papain exhibits specific substrate preferences for hydrophobic or aromatic residues. | Specificity is controlled, however, by the <scene name='Sandbox_39/Active_site_revised/1'>catalytic diad</scene>, a hydrophobic pocket that accommodates the side chains of the protein substrate. This diad, shown above in red and clearly visible in the cleft of the enzyme, consists of cysteine25 (after which the protein is categorized as a cysteine protease)and histidine159. Papain exhibits specific substrate preferences for hydrophobic or aromatic residues. | ||
== Secondary Structure == | |||
== Primary, Secondary, and Tertiary Structure == | |||
Papain is composed of 212 amino acid residues that make up its primary structure. This structure is shown below. | |||
Papain's primary structure causes it to fold into different motifs that make up its secondary structure. These motifs include <scene name='Sandbox_39/Alpha_helices/2'>alpha helices</scene>, shown in green, and <scene name='Sandbox_39/Beta_pleated_sheets/2'>beta pleated sheets</scene>, shown in orange. As shown to the left, papain has 7 alpha helices and 8 beta pleated sheets. All other motifs are nonrandom, structural units, mostly simply turns. | Papain's primary structure causes it to fold into different motifs that make up its secondary structure. These motifs include <scene name='Sandbox_39/Alpha_helices/2'>alpha helices</scene>, shown in green, and <scene name='Sandbox_39/Beta_pleated_sheets/2'>beta pleated sheets</scene>, shown in orange. As shown to the left, papain has 7 alpha helices and 8 beta pleated sheets. All other motifs are nonrandom, structural units, mostly simply turns. | ||
Papain's seconary structures then fold even further to for its three-dimensional structure, which consists of two distinct structural domains with a cleft between them. This cleft contains the catalytic diad discussed above. This tertiary structure is pictured below. | |||
== Polarity and Hydrophobicity == | == Polarity and Hydrophobicity == | ||
