View source for 1rm3

==Crystal structure of mutant T33A of photosynthetic glyceraldehyde-3-phosphate dehydrogenase A4 isoform, complexed with NADP==
<StructureSection load='1rm3' size='340' side='right' caption='[[1rm3]], [[Resolution|resolution]] 2.20&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1rm3]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/Spinacia_oleracea Spinacia oleracea]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1RM3 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1RM3 FirstGlance]. <br>
</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=NDP:NADPH+DIHYDRO-NICOTINAMIDE-ADENINE-DINUCLEOTIDE+PHOSPHATE'>NDP</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene><br>
<tr><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1jn0|1jn0]], [[1nbo|1nbo]], [[1rm4|1rm4]], [[1rm5|1rm5]]</td></tr>
<tr><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">GapA ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=3562 Spinacia oleracea])</td></tr>
<tr><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[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] </span></td></tr>
<tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1rm3 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1rm3 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1rm3 RCSB], [http://www.ebi.ac.uk/pdbsum/1rm3 PDBsum]</span></td></tr>
<table>
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/rm/1rm3_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/chain_selection.php?pdb_ID=2ata ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Chloroplast glyceraldehyde-3-phosphate dehydrogenase (GAPDH) of higher plants uses both NADP(H) and NAD(H) as coenzyme and consists of one (GapA) or two types of subunits (GapA, GapB). AB-GAPDH is regulated in vivo through the action of thioredoxin and metabolites, showing higher kinetic preference for NADPH in the light than in darkness due to a specific effect on kcat(NADPH). Previous crystallographic studies on spinach chloroplast A4-GAPDH complexed with NADP or NAD showed that residues Thr33 and Ser188 are involved in NADP over NAD selectivity by interacting with the 2'-phosphate group of NADP. This suggested a possible involvement of these residues in the regulatory mechanism. Mutants of recombinant spinach GapA (A4-GAPDH) with Thr33 or Ser188 replaced by Ala (T33A, S188A and double mutant T33A/S188A) were produced, expressed in Escherichia coli, and compared to wild-type recombinant A4-GAPDH, in terms of crystal structures and kinetic properties. Affinity for NADPH was decreased significantly in all mutants, and kcat(NADPH) was lowered in mutants carrying the substitution of Ser188. NADH-dependent activity was unaffected. The decrease of kcat/Km of the NADPH-dependent reaction in Ser188 mutants resembles the behaviour of AB-GAPDH inhibited by oxidized thioredoxin, as confirmed by steady-state kinetic analysis of native enzyme. A significant expansion of size of the A4-tetramer was observed in the S188A mutant compared to wild-type A4. We conclude that in the absence of interactions between Ser188 and the 2'-phosphate group of NADP, the enzyme structure relaxes to a less compact conformation, which negatively affects the complex catalytic cycle of GADPH. A model based on this concept might be developed to explain the in vivo light-regulation of the GAPDH.

Coenzyme site-directed mutants of photosynthetic A4-GAPDH show selectively reduced NADPH-dependent catalysis, similar to regulatory AB-GAPDH inhibited by oxidized thioredoxin.,Sparla F, Fermani S, Falini G, Zaffagnini M, Ripamonti A, Sabatino P, Pupillo P, Trost P J Mol Biol. 2004 Jul 23;340(5):1025-37. PMID:15236965<ref>PMID:15236965</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>

==See Also==
*[[Glyceraldehyde-3-Phosphate Dehydrogenase|Glyceraldehyde-3-Phosphate Dehydrogenase]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Spinacia oleracea]]
[[Category: Falini, G.]]
[[Category: Fermani, S.]]
[[Category: Pupillo, P.]]
[[Category: Ripamonti, A.]]
[[Category: Sabatino, P.]]
[[Category: Sparla, F.]]
[[Category: Trost, P.]]
[[Category: Gapdh-nadp complex]]
[[Category: Oxidoreductase]]
[[Category: Rossmann fold]]