This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
5yeq
From Proteopedia
(Difference between revisions)
(New page: '''Unreleased structure''' The entry 5yeq is ON HOLD until Paper Publication Authors: Ko, T.P., Chen, C.Y., Lin, K.F., Lin, B.L., Huang, C.H., Chiang, C.H., Horng, J.C., Tsai, M.D. Des...) |
|||
| (3 intermediate revisions not shown.) | |||
| Line 1: | Line 1: | ||
| - | '''Unreleased structure''' | ||
| - | The | + | ==The structure of Sac-KARI protein== |
| + | <StructureSection load='5yeq' size='340' side='right'caption='[[5yeq]], [[Resolution|resolution]] 1.75Å' scene=''> | ||
| + | == Structural highlights == | ||
| + | <table><tr><td colspan='2'>[[5yeq]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Sulfolobus_acidocaldarius Sulfolobus acidocaldarius]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5YEQ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5YEQ FirstGlance]. <br> | ||
| + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.75Å</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=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=MSE:SELENOMETHIONINE'>MSE</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</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=5yeq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5yeq OCA], [https://pdbe.org/5yeq PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5yeq RCSB], [https://www.ebi.ac.uk/pdbsum/5yeq PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5yeq ProSAT]</span></td></tr> | ||
| + | </table> | ||
| + | == Function == | ||
| + | [https://www.uniprot.org/uniprot/ILVC_SULAC ILVC_SULAC] Involved in the biosynthesis of branched-chain amino acids (BCAA). Catalyzes an alkyl-migration followed by a ketol-acid reduction of (S)-2-acetolactate (S2AL) to yield (R)-2,3-dihydroxy-isovalerate. In the isomerase reaction, S2AL is rearranged via a Mg-dependent methyl migration to produce 3-hydroxy-3-methyl-2-ketobutyrate (HMKB). In the reductase reaction, this 2-ketoacid undergoes a metal-dependent reduction by NADPH to yield (R)-2,3-dihydroxy-isovalerate.[HAMAP-Rule:MF_00435] | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | Ketol-acid reductoisomerase (KARI) is a bifunctional enzyme in the second step of branched-chain amino acids biosynthetic pathway. Most KARIs prefer NADPH as a cofactor. However, KARI with a preference for NADH is desirable in industrial applications including anaerobic fermentation for the production of branched-chain amino acids or biofuels. Here, we characterize a thermoacidophilic archaeal Sac-KARI from Sulfolobus acidocaldarius and present its crystal structure at a 1.75-A resolution. By comparison with other holo-KARI structures, one sulphate ion is observed in each binding site for the 2'-phosphate of NADPH, implicating its NADPH preference. Sac-KARI has very high affinity for NADPH and NADH, with K M values of 0.4 muM for NADPH and 6.0 muM for NADH, suggesting that both are good cofactors at low concentrations although NADPH is favoured over NADH. Furthermore, Sac-KARI can catalyze 2(S)-acetolactate (2S-AL) with either cofactor from 25 to 60 degrees C, but the enzyme has higher activity by using NADPH. In addition, the catalytic activity of Sac-KARI increases significantly with elevated temperatures and reaches an optimum at 60 degrees C. Bi-cofactor utilization and the thermoactivity of Sac-KARI make it a potential candidate for use in metabolic engineering or industrial applications under anaerobic or harsh conditions. | ||
| - | + | NADH/NADPH bi-cofactor-utilizing and thermoactive ketol-acid reductoisomerase from Sulfolobus acidocaldarius.,Chen CY, Ko TP, Lin KF, Lin BL, Huang CH, Chiang CH, Horng JC Sci Rep. 2018 May 8;8(1):7176. doi: 10.1038/s41598-018-25361-4. PMID:29739976<ref>PMID:29739976</ref> | |
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | [[Category: | + | </div> |
| - | [[Category: | + | <div class="pdbe-citations 5yeq" style="background-color:#fffaf0;"></div> |
| - | [[Category: | + | |
| - | [[Category: | + | ==See Also== |
| - | [[Category: Horng | + | *[[Ketol-acid reductoisomerase 3D structures|Ketol-acid reductoisomerase 3D structures]] |
| - | [[Category: | + | == References == |
| - | [[Category: | + | <references/> |
| - | [[Category: | + | __TOC__ |
| - | [[Category: | + | </StructureSection> |
| + | [[Category: Large Structures]] | ||
| + | [[Category: Sulfolobus acidocaldarius]] | ||
| + | [[Category: Chen CY]] | ||
| + | [[Category: Chiang CH]] | ||
| + | [[Category: Horng JC]] | ||
| + | [[Category: Huang CH]] | ||
| + | [[Category: Ko TP]] | ||
| + | [[Category: Lin BL]] | ||
| + | [[Category: Lin KF]] | ||
| + | [[Category: Tsai MD]] | ||
Current revision
The structure of Sac-KARI protein
| |||||||||||
Categories: Large Structures | Sulfolobus acidocaldarius | Chen CY | Chiang CH | Horng JC | Huang CH | Ko TP | Lin BL | Lin KF | Tsai MD
