1jn0
From Proteopedia
(New page: 200px<br /><applet load="1jn0" size="450" color="white" frame="true" align="right" spinBox="true" caption="1jn0, resolution 3.00Å" /> '''Crystal structure of...) |
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| - | [[Image:1jn0.jpg|left|200px]]<br /><applet load="1jn0" size=" | + | [[Image:1jn0.jpg|left|200px]]<br /><applet load="1jn0" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1jn0, resolution 3.00Å" /> | caption="1jn0, resolution 3.00Å" /> | ||
'''Crystal structure of the non-regulatory A4 isoform of spinach chloroplast glyceraldehyde-3-phosphate dehydrogenase complexed with NADP'''<br /> | '''Crystal structure of the non-regulatory A4 isoform of spinach chloroplast glyceraldehyde-3-phosphate dehydrogenase complexed with NADP'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Here, we report the first crystal structure of a photosynthetic | + | Here, we report the first crystal structure of a photosynthetic glyceraldehyde-3-phosphate dehydrogenase (GAPDH) complexed with NADP. The enzyme, purified from spinach chloroplasts, is constituted of a single type of subunit (A) arranged in homotetramers. It shows non-regulated NADP-dependent and NAD-dependent activities, with a preference for NADP. The structure has been solved to 3.0 A resolution by molecular replacement. The crystals belong to space group C222 with three monomers in the asymmetric unit. One of the three monomers generates a tetramer using the space group 222 point symmetry and a very similar tetramer is generated by the other two monomers, related by a non-crystallographic symmetry, using a crystallographic 2-fold axis.The protein reveals a large structural homology with known GAPDHs both in the cofactor-binding domain and in regions of the catalytic domain. Like all other GAPDHs investigated so far, the A(4)-GAPDH belongs to the Rossmann fold family of dehydrogenases. However, unlike most dehydrogenases of this family, the adenosine 2'-phosphate group of NADP does not form a salt-bridge with any positively charged residue in its surroundings, being instead set in place by hydrogen bonds with a threonine residue belonging to the Rossmann fold and a serine residue located in the S-loop of a symmetry-related monomer. While increasing our knowledge of an important photosynthetic enzyme, these results contribute to a general understanding of NADP versus NAD recognition in pyridine nucleotide-dependent enzymes.Although the overall structure of A(4)-GAPDH is similar to that of the cytosolic GAPDH from bacteria and eukaryotes, the chloroplast tetramer is peculiar, in that it can actually be considered a dimer of dimers, since monomers are bound in pairs by a disulphide bridge formed across Cys200 residues. This bridge is not found in other cytosolic or chloroplast GAPDHs from animals, bacteria, or plants other than spinach. |
==About this Structure== | ==About this Structure== | ||
| - | 1JN0 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Spinacia_oleracea Spinacia oleracea] with SO4 and NDP as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Glyceraldehyde-3-phosphate_dehydrogenase_(NADP(+))_(phosphorylating) Glyceraldehyde-3-phosphate dehydrogenase (NADP(+)) (phosphorylating)], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.2.1.13 1.2.1.13] Full crystallographic information is available from [http:// | + | 1JN0 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Spinacia_oleracea Spinacia oleracea] with <scene name='pdbligand=SO4:'>SO4</scene> and <scene name='pdbligand=NDP:'>NDP</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Glyceraldehyde-3-phosphate_dehydrogenase_(NADP(+))_(phosphorylating) Glyceraldehyde-3-phosphate dehydrogenase (NADP(+)) (phosphorylating)], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.2.1.13 1.2.1.13] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1JN0 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: rossman fold]] | [[Category: rossman fold]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:24:31 2008'' |
Revision as of 11:24, 21 February 2008
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Crystal structure of the non-regulatory A4 isoform of spinach chloroplast glyceraldehyde-3-phosphate dehydrogenase complexed with NADP
Overview
Here, we report the first crystal structure of a photosynthetic glyceraldehyde-3-phosphate dehydrogenase (GAPDH) complexed with NADP. The enzyme, purified from spinach chloroplasts, is constituted of a single type of subunit (A) arranged in homotetramers. It shows non-regulated NADP-dependent and NAD-dependent activities, with a preference for NADP. The structure has been solved to 3.0 A resolution by molecular replacement. The crystals belong to space group C222 with three monomers in the asymmetric unit. One of the three monomers generates a tetramer using the space group 222 point symmetry and a very similar tetramer is generated by the other two monomers, related by a non-crystallographic symmetry, using a crystallographic 2-fold axis.The protein reveals a large structural homology with known GAPDHs both in the cofactor-binding domain and in regions of the catalytic domain. Like all other GAPDHs investigated so far, the A(4)-GAPDH belongs to the Rossmann fold family of dehydrogenases. However, unlike most dehydrogenases of this family, the adenosine 2'-phosphate group of NADP does not form a salt-bridge with any positively charged residue in its surroundings, being instead set in place by hydrogen bonds with a threonine residue belonging to the Rossmann fold and a serine residue located in the S-loop of a symmetry-related monomer. While increasing our knowledge of an important photosynthetic enzyme, these results contribute to a general understanding of NADP versus NAD recognition in pyridine nucleotide-dependent enzymes.Although the overall structure of A(4)-GAPDH is similar to that of the cytosolic GAPDH from bacteria and eukaryotes, the chloroplast tetramer is peculiar, in that it can actually be considered a dimer of dimers, since monomers are bound in pairs by a disulphide bridge formed across Cys200 residues. This bridge is not found in other cytosolic or chloroplast GAPDHs from animals, bacteria, or plants other than spinach.
About this Structure
1JN0 is a Single protein structure of sequence from Spinacia oleracea with and as ligands. Active as Glyceraldehyde-3-phosphate dehydrogenase (NADP(+)) (phosphorylating), with EC number 1.2.1.13 Full crystallographic information is available from OCA.
Reference
Crystal structure of the non-regulatory A(4 )isoform of spinach chloroplast glyceraldehyde-3-phosphate dehydrogenase complexed with NADP., Fermani S, Ripamonti A, Sabatino P, Zanotti G, Scagliarini S, Sparla F, Trost P, Pupillo P, J Mol Biol. 2001 Nov 30;314(3):527-42. PMID:11846565
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