View source for 4itb


==Structure of bacterial enzyme in complex with cofactor and substrate==
<StructureSection load='4itb' size='340' side='right'caption='[[4itb]], [[Resolution|resolution]] 1.40&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4itb]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Synechococcus_sp._PCC_7002 Synechococcus sp. PCC 7002]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4ITB OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4ITB FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=EDO:1,2-ETHANEDIOL'>EDO</scene>, <scene name='pdbligand=NDP:NADPH+DIHYDRO-NICOTINAMIDE-ADENINE-DINUCLEOTIDE+PHOSPHATE'>NDP</scene>, <scene name='pdbligand=SSN:4-OXOBUTANOIC+ACID'>SSN</scene></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=4itb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4itb OCA], [https://pdbe.org/4itb PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4itb RCSB], [https://www.ebi.ac.uk/pdbsum/4itb PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4itb ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/B1XMM6_SYNP2 B1XMM6_SYNP2] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Succinic semialdehyde dehydrogenase (SSADH) from cyanobacterium Synechococcus differs from other SSADHs in the gamma-aminobutyrate shunt. Synechococcus SSADH (SySSADH) is a TCA cycle enzyme and completes a 2-oxoglutarate dehydrogenase-deficient cyanobacterial TCA cycle through a detour metabolic pathway. SySSADH produces succinate in an NADP(+)-dependent manner with a single cysteine acting as the catalytic residue in the catalytic loop. Crystal structures of SySSADH were determined in their apo form, as a binary complex with NADP(+) and as a ternary complex with succinic semialdehyde and NADPH, providing details about the catalytic mechanism by revealing a covalent adduct of a cofactor with the catalytic cysteine in the binary complex and a proposed thiohemiacetal intermediate in the ternary complex. Further analyses showed that SySSADH is an oxidation-sensitive enzyme and that the formation of the NADP-cysteine adduct is a kinetically preferred event that protects the catalytic cysteine from H2O2-dependent oxidative stress. These structural and functional features of SySSADH provide a molecular basis for cofactor-dependent oxidation protection in 1-Cys SSADH, which is unique relative to other 2-Cys SSADHs employing a redox-dependent formation of a disulfide bridge.

Structural Basis for a Cofactor-dependent Oxidation Protection and Catalysis of Cyanobacterial Succinic Semialdehyde Dehydrogenase.,Park J, Rhee S J Biol Chem. 2013 May 31;288(22):15760-70. doi: 10.1074/jbc.M113.460428. Epub, 2013 Apr 15. PMID:23589281<ref>PMID:23589281</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4itb" style="background-color:#fffaf0;"></div>

==See Also==
*[[Succinate-semialdehyde dehydrogenase|Succinate-semialdehyde dehydrogenase]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Synechococcus sp. PCC 7002]]
[[Category: Park J]]
[[Category: Rhee S]]