1lcp
From Proteopedia
(New page: 200px<br /><applet load="1lcp" size="450" color="white" frame="true" align="right" spinBox="true" caption="1lcp, resolution 1.65Å" /> '''BOVINE LENS LEUCINE ...) |
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| - | [[Image:1lcp.gif|left|200px]]<br /><applet load="1lcp" size=" | + | [[Image:1lcp.gif|left|200px]]<br /><applet load="1lcp" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1lcp, resolution 1.65Å" /> | caption="1lcp, resolution 1.65Å" /> | ||
'''BOVINE LENS LEUCINE AMINOPEPTIDASE COMPLEXED WITH L-LEUCINE PHOSPHONIC ACID'''<br /> | '''BOVINE LENS LEUCINE AMINOPEPTIDASE COMPLEXED WITH L-LEUCINE PHOSPHONIC ACID'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The three-dimensional structure of bovine lens leucine aminopeptidase | + | The three-dimensional structure of bovine lens leucine aminopeptidase (blLAP) complexed with L-Leucinephosphonic acid (LeuP) has been determined by molecular replacement using the structure of native blLAP as a starting model. Cocrystallization of the enzyme with the inhibitor yielded a new crystal form of space group P321 which has cell dimensions a = 130.4 A and c = 125.4 A. Refinement of the model against data from 7.0 to 1.65 A resolution resulted in a final structure with a crystallographic residual of 0.160 (R(free) = 0.191). The N-terminal amino group of LeuP is coordinated to Zn-489, one phosphoryl oxygen atom bridges both metal ions, and another phosphoryl oxygen atom is coordinated to Zn-488. The side chain of Arg-336 interacts with the inhibitor via three water molecules. LeuP resembles the presumed tetrahedral gem-diolate transition state after direct attack of a water or hydroxide ion nucleophile on the scissile peptide bond. On the basis of the LeuP binding mode and the previous structural and biochemical data, three plausible reaction pathways are evaluated. The two-metal ion mechanisms discussed herein share as common features a metal-bound hydroxide ion nucleophile and polarization of the carbonyl group by the zinc ions. Possible catalytic roles of Arg-336 and Lys-262 in the direct or indirect (through H2O) protonation of the leaving group, in the stabilization of a zinc-bound OH- nucleophile and in the stabilization of the negatively charged intermediate, are discussed. A site 3 metal ion approximately 12 A away from the active site 2 zinc ion probably serves a structural role. |
==About this Structure== | ==About this Structure== | ||
| - | 1LCP 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, PLU 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:// | + | 1LCP 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=PLU:'>PLU</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=1LCP 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: MRD]] | [[Category: MRD]] | ||
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[[Category: hydrolase (alpha-aminoacylpeptide)]] | [[Category: hydrolase (alpha-aminoacylpeptide)]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:43:43 2008'' |
Revision as of 11:43, 21 February 2008
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BOVINE LENS LEUCINE AMINOPEPTIDASE COMPLEXED WITH L-LEUCINE PHOSPHONIC ACID
Overview
The three-dimensional structure of bovine lens leucine aminopeptidase (blLAP) complexed with L-Leucinephosphonic acid (LeuP) has been determined by molecular replacement using the structure of native blLAP as a starting model. Cocrystallization of the enzyme with the inhibitor yielded a new crystal form of space group P321 which has cell dimensions a = 130.4 A and c = 125.4 A. Refinement of the model against data from 7.0 to 1.65 A resolution resulted in a final structure with a crystallographic residual of 0.160 (R(free) = 0.191). The N-terminal amino group of LeuP is coordinated to Zn-489, one phosphoryl oxygen atom bridges both metal ions, and another phosphoryl oxygen atom is coordinated to Zn-488. The side chain of Arg-336 interacts with the inhibitor via three water molecules. LeuP resembles the presumed tetrahedral gem-diolate transition state after direct attack of a water or hydroxide ion nucleophile on the scissile peptide bond. On the basis of the LeuP binding mode and the previous structural and biochemical data, three plausible reaction pathways are evaluated. The two-metal ion mechanisms discussed herein share as common features a metal-bound hydroxide ion nucleophile and polarization of the carbonyl group by the zinc ions. Possible catalytic roles of Arg-336 and Lys-262 in the direct or indirect (through H2O) protonation of the leaving group, in the stabilization of a zinc-bound OH- nucleophile and in the stabilization of the negatively charged intermediate, are discussed. A site 3 metal ion approximately 12 A away from the active site 2 zinc ion probably serves a structural role.
About this Structure
1LCP is a Single protein structure of sequence from Bos taurus with , and as ligands. Active as Leucyl aminopeptidase, with EC number 3.4.11.1 Full crystallographic information is available from OCA.
Reference
Transition state analogue L-leucinephosphonic acid bound to bovine lens leucine aminopeptidase: X-ray structure at 1.65 A resolution in a new crystal form., Strater N, Lipscomb WN, Biochemistry. 1995 Jul 18;34(28):9200-10. PMID:7619821
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