1xpy: Difference between revisions

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[[Image:1xpy.gif|left|200px]]<br /><applet load="1xpy" size="~~450~~" color="white" frame="true" align="right" spinBox="true"

[[Image:1xpy.gif|left|200px]]<br /><applet load="1xpy" size="350" color="white" frame="true" align="right" spinBox="true"

caption="1xpy, resolution 2.30Å" />

'''Structural Basis for Catalytic Racemization and Substrate Specificity of an N-Acylamino Acid Racemase Homologue from Deinococcus radiodurans'''<br />

==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.

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.

==About this Structure==

1XPY is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Deinococcus_radiodurans Deinococcus radiodurans] with MG and NLQ as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://~~ispc~~.weizmann.ac.il/oca-bin/ocashort?id=1XPY OCA].

1XPY is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Deinococcus_radiodurans Deinococcus radiodurans] with <scene name='pdbligand=MG:'>MG</scene> and <scene name='pdbligand=NLQ:'>NLQ</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1XPY OCA].

==Reference==

Line 13:

[[Category: Deinococcus radiodurans]]

[[Category: Single protein]]

[[Category: Chen, C.Y.]]

[[Category: Chen, C Y.]]

[[Category: Chiu, W.C.]]

[[Category: Chiu, W C.]]

[[Category: Hsu, S.K.]]

[[Category: Hsu, S K.]]

[[Category: Hsu, W.H.]]

[[Category: Hsu, W H.]]

[[Category: Liu, J.S.]]

[[Category: Liu, J S.]]

[[Category: Wang, W.C.]]

[[Category: Wang, W C.]]

[[Category: Wu, C.L.]]

[[Category: Wu, C L.]]

[[Category: MG]]

[[Category: NLQ]]

[[Category: racemase]]

''Page seeded by [http://~~ispc~~.weizmann.ac.il/oca OCA ] on ~~Sun Nov 25 02~~:40:~~56 2007~~''

''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:57:22 2008''

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@@ Line 1: / Line 1: @@
-[[Image:1xpy.gif|left|200px]]<br /><applet load="1xpy" size="450" color="white" frame="true" align="right" spinBox="true"
+[[Image:1xpy.gif|left|200px]]<br /><applet load="1xpy" size="350" color="white" frame="true" align="right" spinBox="true"
 caption="1xpy, resolution 2.30&Aring;" />
 '''Structural Basis for Catalytic Racemization and Substrate Specificity of an N-Acylamino Acid Racemase Homologue from Deinococcus radiodurans'''<br />
 ==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.
+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.
 ==About this Structure==
-XPY is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Deinococcus_radiodurans Deinococcus radiodurans] with MG and NLQ as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1XPY OCA].
+XPY is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Deinococcus_radiodurans Deinococcus radiodurans] with <scene name='pdbligand=MG:'>MG</scene> and <scene name='pdbligand=NLQ:'>NLQ</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1XPY OCA].
 ==Reference==
@@ Line 13: / Line 13: @@
 [[Category: Deinococcus radiodurans]]
 [[Category: Single protein]]
-[[Category: Chen, C.Y.]]
+[[Category: Chen, C Y.]]
-[[Category: Chiu, W.C.]]
+[[Category: Chiu, W C.]]
-[[Category: Hsu, S.K.]]
+[[Category: Hsu, S K.]]
-[[Category: Hsu, W.H.]]
+[[Category: Hsu, W H.]]
-[[Category: Liu, J.S.]]
+[[Category: Liu, J S.]]
-[[Category: Wang, W.C.]]
+[[Category: Wang, W C.]]
-[[Category: Wu, C.L.]]
+[[Category: Wu, C L.]]
 [[Category: MG]]
 [[Category: NLQ]]
 [[Category: racemase]]
-''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Sun Nov 25 02:40:56 2007''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:57:22 2008''