From Proteopedia
(Difference between revisions)
proteopedia linkproteopedia link
|
|
Line 1: |
Line 1: |
- | [[Image:1xpy.gif|left|200px]] | + | {{Seed}} |
| + | [[Image:1xpy.png|left|200px]] |
| | | |
| <!-- | | <!-- |
Line 9: |
Line 10: |
| {{STRUCTURE_1xpy| PDB=1xpy | SCENE= }} | | {{STRUCTURE_1xpy| PDB=1xpy | SCENE= }} |
| | | |
- | '''Structural Basis for Catalytic Racemization and Substrate Specificity of an N-Acylamino Acid Racemase Homologue from Deinococcus radiodurans'''
| + | ===Structural Basis for Catalytic Racemization and Substrate Specificity of an N-Acylamino Acid Racemase Homologue from Deinococcus radiodurans=== |
| | | |
| | | |
- | ==Overview==
| + | <!-- |
- | N-acylamino acid racemase (NAAAR) catalyzes the racemization of N-acylamino acids and can be used in concert with an aminoacylase to produce enantiopure alpha-amino acids, a process that has potential industrial applications. Here we have cloned and characterized an NAAAR homologue from a radiation-resistant ancient bacterium, Deinococcus radiodurans. The expressed NAAAR racemized various substrates at an optimal temperature of 60 degrees C and had Km values of 24.8 mM and 12.3 mM for N-acetyl-D-methionine and N-acetyl-L-methionine, respectively. The crystal structure of NAAAR was solved to 1.3 A resolution using multiwavelength anomalous dispersion (MAD) methods. The structure consists of a homooctamer in which each subunit has an architecture characteristic of enolases with a capping domain and a (beta/alpha)7 beta barrel domain. The NAAAR.Mg2+ and NAAAR.N-acetyl-L-glutamine.Mg2+ structures were also determined, allowing us to define the Lys170-Asp195-Glu220-Asp245-Lys269 framework for catalyzing 1,1-proton exchange of N-acylamino acids. Four subsites enclosing the substrate are identified: catalytic site, metal-binding site, side-chain-binding region, and a flexible lid region. The high conservation of catalytic and metal-binding sites in different enolases reflects the essentiality of a common catalytic platform, allowing these enzymes to robustly abstract alpha-protons of various carboxylate substrates efficiently. The other subsites involved in substrate recognition are less conserved, suggesting that divergent evolution has led to functionally distinct enzymes.
| + | The line below this paragraph, {{ABSTRACT_PUBMED_15313614}}, adds the Publication Abstract to the page |
| + | (as it appears on PubMed at http://www.pubmed.gov), where 15313614 is the PubMed ID number. |
| + | --> |
| + | {{ABSTRACT_PUBMED_15313614}} |
| | | |
| ==About this Structure== | | ==About this Structure== |
Line 30: |
Line 34: |
| [[Category: Wu, C L.]] | | [[Category: Wu, C L.]] |
| [[Category: Racemase]] | | [[Category: Racemase]] |
- | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 15:20:59 2008'' | + | |
| + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Jul 28 06:02:31 2008'' |
Revision as of 03:02, 28 July 2008
Template:STRUCTURE 1xpy
Structural Basis for Catalytic Racemization and Substrate Specificity of an N-Acylamino Acid Racemase Homologue from Deinococcus radiodurans
Template:ABSTRACT PUBMED 15313614
About this Structure
1XPY is a Single protein structure of sequence from Deinococcus radiodurans. Full crystallographic information is available from OCA.
Reference
Structural basis for catalytic racemization and substrate specificity of an N-acylamino acid racemase homologue from Deinococcus radiodurans., Wang WC, Chiu WC, Hsu SK, Wu CL, Chen CY, Liu JS, Hsu WH, J Mol Biol. 2004 Sep 3;342(1):155-69. PMID:15313614
Page seeded by OCA on Mon Jul 28 06:02:31 2008