1s20
From Proteopedia
(New page: 200px<br /><applet load="1s20" size="450" color="white" frame="true" align="right" spinBox="true" caption="1s20, resolution 2.20Å" /> '''A novel NAD binding ...) |
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| - | [[Image:1s20.gif|left|200px]]<br /><applet load="1s20" size=" | + | [[Image:1s20.gif|left|200px]]<br /><applet load="1s20" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1s20, resolution 2.20Å" /> | caption="1s20, resolution 2.20Å" /> | ||
'''A novel NAD binding protein revealed by the crystal structure of E. Coli 2,3-diketogulonate reductase (YiaK)'''<br /> | '''A novel NAD binding protein revealed by the crystal structure of E. Coli 2,3-diketogulonate reductase (YiaK)'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Escherichia coli YiaK catalyzes the reduction of 2,3-diketo-L-gulonate in | + | Escherichia coli YiaK catalyzes the reduction of 2,3-diketo-L-gulonate in the presence of NADH. It belongs to a large family of oxidoreductases that is conserved in archaea, bacteria, and eukaryotes but shows no sequence homology to other proteins. We report here the crystal structures at up to 2.0-A resolution of YiaK alone and in complex with NAD-tartrate. YiaK has a new polypeptide backbone fold and a novel mode of recognizing the NAD cofactor. In addition, NAD is bound in an unusual conformation, at the interface of a dimer of the enzyme. The crystallographic analysis unexpectedly revealed the binding of tartrate in the active site. Enzyme kinetics studies confirm that tartrate and the related D-malate are inhibitors of YiaK. In contrast to most other enzymes where substrate binding produces a more closed conformation, the binding of NAD-tartrate to YiaK produces a more open active site. The free enzyme conformation is incompatible with NAD binding. His(44) is likely the catalytic residue of the enzyme. |
==About this Structure== | ==About this Structure== | ||
| - | 1S20 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with TLA and NAD as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1S20 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with <scene name='pdbligand=TLA:'>TLA</scene> and <scene name='pdbligand=NAD:'>NAD</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1S20 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Acton, T | + | [[Category: Acton, T B.]] |
[[Category: Benach, J.]] | [[Category: Benach, J.]] | ||
[[Category: Forouhar, F.]] | [[Category: Forouhar, F.]] | ||
[[Category: Kulkarni, K.]] | [[Category: Kulkarni, K.]] | ||
[[Category: Lee, I.]] | [[Category: Lee, I.]] | ||
| - | [[Category: Montelione, G | + | [[Category: Montelione, G T.]] |
[[Category: Tong, L.]] | [[Category: Tong, L.]] | ||
[[Category: Xiao, R.]] | [[Category: Xiao, R.]] | ||
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[[Category: alpha beta dimeric protein]] | [[Category: alpha beta dimeric protein]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:57:02 2008'' |
Revision as of 12:57, 21 February 2008
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A novel NAD binding protein revealed by the crystal structure of E. Coli 2,3-diketogulonate reductase (YiaK)
Overview
Escherichia coli YiaK catalyzes the reduction of 2,3-diketo-L-gulonate in the presence of NADH. It belongs to a large family of oxidoreductases that is conserved in archaea, bacteria, and eukaryotes but shows no sequence homology to other proteins. We report here the crystal structures at up to 2.0-A resolution of YiaK alone and in complex with NAD-tartrate. YiaK has a new polypeptide backbone fold and a novel mode of recognizing the NAD cofactor. In addition, NAD is bound in an unusual conformation, at the interface of a dimer of the enzyme. The crystallographic analysis unexpectedly revealed the binding of tartrate in the active site. Enzyme kinetics studies confirm that tartrate and the related D-malate are inhibitors of YiaK. In contrast to most other enzymes where substrate binding produces a more closed conformation, the binding of NAD-tartrate to YiaK produces a more open active site. The free enzyme conformation is incompatible with NAD binding. His(44) is likely the catalytic residue of the enzyme.
About this Structure
1S20 is a Single protein structure of sequence from Escherichia coli with and as ligands. Full crystallographic information is available from OCA.
Reference
A novel NAD-binding protein revealed by the crystal structure of 2,3-diketo-L-gulonate reductase (YiaK)., Forouhar F, Lee I, Benach J, Kulkarni K, Xiao R, Acton TB, Montelione GT, Tong L, J Biol Chem. 2004 Mar 26;279(13):13148-55. Epub 2004 Jan 12. PMID:14718529
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