1euh
From Proteopedia
(New page: 200px<br /><applet load="1euh" size="450" color="white" frame="true" align="right" spinBox="true" caption="1euh, resolution 1.82Å" /> '''APO FORM OF A NADP D...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1euh.jpg|left|200px]]<br /><applet load="1euh" size=" | + | [[Image:1euh.jpg|left|200px]]<br /><applet load="1euh" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1euh, resolution 1.82Å" /> | caption="1euh, resolution 1.82Å" /> | ||
'''APO FORM OF A NADP DEPENDENT ALDEHYDE DEHYDROGENASE FROM STREPTOCOCCUS MUTANS'''<br /> | '''APO FORM OF A NADP DEPENDENT ALDEHYDE DEHYDROGENASE FROM STREPTOCOCCUS MUTANS'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The aldehyde dehydrogenases (ALDHs) are a superfamily of multimeric | + | The aldehyde dehydrogenases (ALDHs) are a superfamily of multimeric enzymes which catalyse the oxidation of a broad range of aldehydes into their corresponding carboxylic acids with the reduction of their cofactor, NAD or NADP, into NADH or NADPH. At present, the only known structures concern NAD-dependent ALDHs. Three structures are available in the Protein Data Bank: two are tetrameric and the other is a dimer. We solved by molecular replacement the first structure of an NADP-dependent ALDH isolated from Streptococcus mutans, in its apo form and holo form in complex with NADP, at 1.8 and 2.6 A resolution, respectively. Although the protein sequence shares only approximately 30 % identity with the other solved tetrameric ALDHs, the structures are very similar. However, a large local conformational change in the region surrounding the 2' phosphate group of the adenosine moiety is observed when the enzyme binds NADP, in contrast to the NAD-dependent ALDHs.Structure and sequence analyses reveal several properties. A small number of residues seem to determine the oligomeric state. Likewise, the nature (charge and volume) of the residue at position 180 (Thr in ALDH from S. mutans) determines the cofactor specificity in comparison with the structures of NAD-dependent ALDHs. The presence of a hydrogen bond network around the cofactor not only allows it to bind to the enzyme but also directs the side-chains in a correct orientation for the catalytic reaction to take place. Moreover, a specific part of this network appears to be important in substrate binding. Since the enzyme oxidises the same substrate, glyceraldehyde-3-phosphate (G3P), as NAD-dependent phosphorylating glyceraldehyde-3-phosphate dehydrogenases (GAPDH), the active site of GAPDH was compared with that of the S. mutans ALDH. It was found that Arg103, Arg283 and Asp440 might be key residues for substrate binding. |
==About this Structure== | ==About this Structure== | ||
| - | 1EUH is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Streptococcus_mutans Streptococcus mutans] with SO4 as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Glyceraldehyde-3-phosphate_dehydrogenase_(NADP(+)) Glyceraldehyde-3-phosphate dehydrogenase (NADP(+))], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.2.1.9 1.2.1.9] Full crystallographic information is available from [http:// | + | 1EUH is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Streptococcus_mutans Streptococcus mutans] with <scene name='pdbligand=SO4:'>SO4</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Glyceraldehyde-3-phosphate_dehydrogenase_(NADP(+)) Glyceraldehyde-3-phosphate dehydrogenase (NADP(+))], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.2.1.9 1.2.1.9] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1EUH OCA]. |
==Reference== | ==Reference== | ||
| Line 23: | Line 23: | ||
[[Category: oxidoreductase]] | [[Category: oxidoreductase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:31:37 2008'' |
Revision as of 10:31, 21 February 2008
|
APO FORM OF A NADP DEPENDENT ALDEHYDE DEHYDROGENASE FROM STREPTOCOCCUS MUTANS
Overview
The aldehyde dehydrogenases (ALDHs) are a superfamily of multimeric enzymes which catalyse the oxidation of a broad range of aldehydes into their corresponding carboxylic acids with the reduction of their cofactor, NAD or NADP, into NADH or NADPH. At present, the only known structures concern NAD-dependent ALDHs. Three structures are available in the Protein Data Bank: two are tetrameric and the other is a dimer. We solved by molecular replacement the first structure of an NADP-dependent ALDH isolated from Streptococcus mutans, in its apo form and holo form in complex with NADP, at 1.8 and 2.6 A resolution, respectively. Although the protein sequence shares only approximately 30 % identity with the other solved tetrameric ALDHs, the structures are very similar. However, a large local conformational change in the region surrounding the 2' phosphate group of the adenosine moiety is observed when the enzyme binds NADP, in contrast to the NAD-dependent ALDHs.Structure and sequence analyses reveal several properties. A small number of residues seem to determine the oligomeric state. Likewise, the nature (charge and volume) of the residue at position 180 (Thr in ALDH from S. mutans) determines the cofactor specificity in comparison with the structures of NAD-dependent ALDHs. The presence of a hydrogen bond network around the cofactor not only allows it to bind to the enzyme but also directs the side-chains in a correct orientation for the catalytic reaction to take place. Moreover, a specific part of this network appears to be important in substrate binding. Since the enzyme oxidises the same substrate, glyceraldehyde-3-phosphate (G3P), as NAD-dependent phosphorylating glyceraldehyde-3-phosphate dehydrogenases (GAPDH), the active site of GAPDH was compared with that of the S. mutans ALDH. It was found that Arg103, Arg283 and Asp440 might be key residues for substrate binding.
About this Structure
1EUH is a Single protein structure of sequence from Streptococcus mutans with as ligand. Active as Glyceraldehyde-3-phosphate dehydrogenase (NADP(+)), with EC number 1.2.1.9 Full crystallographic information is available from OCA.
Reference
Apo and holo crystal structures of an NADP-dependent aldehyde dehydrogenase from Streptococcus mutans., Cobessi D, Tete-Favier F, Marchal S, Azza S, Branlant G, Aubry A, J Mol Biol. 1999 Jul 2;290(1):161-73. PMID:10388564
Page seeded by OCA on Thu Feb 21 12:31:37 2008
