Aminopeptidase
From Proteopedia
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| - | + | Aminopeptidases catalyze a release of an N-terminal amino acid from a peptide, amide, or arylamide. | |
| - | + | S. griseus Aminopeptidase (SGAP) cleaves the N-terminal amino acid from a peptide or protein, and is specific for larger hydrophobic acids, especially leucine. No cleavage occurs if the next residue is proline. | |
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The active site of the enzyme contains two Zn2+ ions with His85 and Asp160 as ligands for one ion, and Glu132 and His247 as ligands for the second ion. Asp97 is a common ligand to both ions. What appears to be a phosphate anion is bound to both zinc atoms, replacing the water molecule/hydroxide ion normally found in this class of enzyme. | The active site of the enzyme contains two Zn2+ ions with His85 and Asp160 as ligands for one ion, and Glu132 and His247 as ligands for the second ion. Asp97 is a common ligand to both ions. What appears to be a phosphate anion is bound to both zinc atoms, replacing the water molecule/hydroxide ion normally found in this class of enzyme. | ||
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| - | The enzyme's activity is modulated by Calcium cations. This structure revealed a calcium binding site near the N-terminus, involving Ile4, Asp262, Asp266, two water molecules, and Asp3. This site, however, is quite distant from the active site, and it was unclear how this might modulate enzymatic activity. | ||
Revision as of 09:37, 7 November 2007
Aminopeptidases catalyze a release of an N-terminal amino acid from a peptide, amide, or arylamide.
S. griseus Aminopeptidase (SGAP) cleaves the N-terminal amino acid from a peptide or protein, and is specific for larger hydrophobic acids, especially leucine. No cleavage occurs if the next residue is proline.
The active site of the enzyme contains two Zn2+ ions with His85 and Asp160 as ligands for one ion, and Glu132 and His247 as ligands for the second ion. Asp97 is a common ligand to both ions. What appears to be a phosphate anion is bound to both zinc atoms, replacing the water molecule/hydroxide ion normally found in this class of enzyme.
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