1lan: Difference between revisions
New page: left|200px<br /><applet load="1lan" size="450" color="white" frame="true" align="right" spinBox="true" caption="1lan, resolution 1.9Å" /> '''LEUCINE AMINOPEPTIDAS... |
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[[Image:1lan.gif|left|200px]]<br /><applet load="1lan" size=" | [[Image:1lan.gif|left|200px]]<br /><applet load="1lan" size="350" color="white" frame="true" align="right" spinBox="true" | ||
caption="1lan, resolution 1.9Å" /> | caption="1lan, resolution 1.9Å" /> | ||
'''LEUCINE AMINOPEPTIDASE COMPLEX WITH L-LEUCINAL'''<br /> | '''LEUCINE AMINOPEPTIDASE COMPLEX WITH L-LEUCINAL'''<br /> | ||
==Overview== | ==Overview== | ||
The three-dimensional structures of bovine lens leucine aminopeptidase | The three-dimensional structures of bovine lens leucine aminopeptidase (blLAP) complexed with L-leucinal and of the unliganded enzyme have been determined at crystallographic resolutions of 1.9 and 1.6 A, respectively. Leucinal binds as a hydrated gem-diol to the active site of b1LAP), resembling the presumed gem-diolated intermediate in the catalytic pathway. One hydroxyl group bridges the two active site metal ions, and the other OH group is coordinated to Zn1. The high-resolution structure of the unliganded enzyme reveals one metal-bound water ligand, which is bridging both zinc ions. Together, these structures support a mechanism in which the bridging water ligand is the attacking hydroxide ion nucleophile. The gem-diolate intermediate is probably stabilized by four coordinating bonds to the dizinc center and by interaction with Lys-262 and Arg-336. In the mechanism, Lys-262 polarizes the peptide carbonyl group, which is also coordinated to Zn1. The Arg-336 side chain interacts with the substrate and the gem-diolate intermediate via water molecules. Near Arg-336 in the b1LAP-leucinal structure, an unusually short hydrogen bond is found between two active site water molecules. | ||
==About this Structure== | ==About this Structure== | ||
1LAN is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus] with ZN, LEU and MRD as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Leucyl_aminopeptidase Leucyl aminopeptidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.11.1 3.4.11.1] Full crystallographic information is available from [http:// | 1LAN is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bos_taurus Bos taurus] with <scene name='pdbligand=ZN:'>ZN</scene>, <scene name='pdbligand=LEU:'>LEU</scene> and <scene name='pdbligand=MRD:'>MRD</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Leucyl_aminopeptidase Leucyl aminopeptidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.11.1 3.4.11.1] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1LAN OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: Leucyl aminopeptidase]] | [[Category: Leucyl aminopeptidase]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Lipscomb, W | [[Category: Lipscomb, W N.]] | ||
[[Category: Straeter, N.]] | [[Category: Straeter, N.]] | ||
[[Category: LEU]] | [[Category: LEU]] | ||
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[[Category: metallopeptidase]] | [[Category: metallopeptidase]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:43:07 2008'' | ||
Revision as of 11:43, 21 February 2008
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LEUCINE AMINOPEPTIDASE COMPLEX WITH L-LEUCINAL
Overview
The three-dimensional structures of bovine lens leucine aminopeptidase (blLAP) complexed with L-leucinal and of the unliganded enzyme have been determined at crystallographic resolutions of 1.9 and 1.6 A, respectively. Leucinal binds as a hydrated gem-diol to the active site of b1LAP), resembling the presumed gem-diolated intermediate in the catalytic pathway. One hydroxyl group bridges the two active site metal ions, and the other OH group is coordinated to Zn1. The high-resolution structure of the unliganded enzyme reveals one metal-bound water ligand, which is bridging both zinc ions. Together, these structures support a mechanism in which the bridging water ligand is the attacking hydroxide ion nucleophile. The gem-diolate intermediate is probably stabilized by four coordinating bonds to the dizinc center and by interaction with Lys-262 and Arg-336. In the mechanism, Lys-262 polarizes the peptide carbonyl group, which is also coordinated to Zn1. The Arg-336 side chain interacts with the substrate and the gem-diolate intermediate via water molecules. Near Arg-336 in the b1LAP-leucinal structure, an unusually short hydrogen bond is found between two active site water molecules.
About this Structure
1LAN is a Single protein structure of sequence from Bos taurus with ZN, LEU and MRD as ligands. Active as Leucyl aminopeptidase, with EC number 3.4.11.1 Full crystallographic information is available from OCA.
Reference
Two-metal ion mechanism of bovine lens leucine aminopeptidase: active site solvent structure and binding mode of L-leucinal, a gem-diolate transition state analogue, by X-ray crystallography., Strater N, Lipscomb WN, Biochemistry. 1995 Nov 14;34(45):14792-800. PMID:7578088
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