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5yeq

From Proteopedia

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Current revision

The structure of Sac-KARI protein

Structural highlights

5yeq is a 2 chain structure with sequence from Sulfolobus acidocaldarius. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 1.75Å
Ligands:	, , ,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

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]

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^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Chen CY, Ko TP, Lin KF, Lin BL, Huang CH, Chiang CH, Horng JC. NADH/NADPH bi-cofactor-utilizing and thermoactive ketol-acid reductoisomerase from Sulfolobus acidocaldarius. Sci Rep. 2018 May 8;8(1):7176. doi: 10.1038/s41598-018-25361-4. PMID:29739976 doi:http://dx.doi.org/10.1038/s41598-018-25361-4

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 See Also
5 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/5yeq"

@@ Line 1: / Line 1: @@
 ==The structure of Sac-KARI protein==
-<StructureSection load='5yeq' size='340' side='right' caption='[[5yeq]], [[Resolution|resolution]] 1.75&Aring;' scene=''>
+<StructureSection load='5yeq' size='340' side='right'caption='[[5yeq]], [[Resolution|resolution]] 1.75&Aring;' scene=''>
 == Structural highlights ==
-<table><tr><td colspan='2'>[[5yeq]] is a 2 chain structure. 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 [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5YEQ FirstGlance]. <br>
+<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='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=EDO:1,2-ETHANEDIOL'>EDO</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr>
+</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.75&#8491;</td></tr>
-<tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=MSE:SELENOMETHIONINE'>MSE</scene></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='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Ketol-acid_reductoisomerase Ketol-acid reductoisomerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.1.1.86 1.1.1.86] </span></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>
-<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5yeq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5yeq OCA], [http://pdbe.org/5yeq PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5yeq RCSB], [http://www.ebi.ac.uk/pdbsum/5yeq PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5yeq ProSAT]</span></td></tr>
 </table>
 == Function ==
-[[http://www.uniprot.org/uniprot/A0A0U3H6N8_9CREN A0A0U3H6N8_9CREN]] 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]
+[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 ==
@@ Line 20: / Line 19: @@
 </div>
 <div class="pdbe-citations 5yeq" style="background-color:#fffaf0;"></div>
+==See Also==
+*[[Ketol-acid reductoisomerase 3D structures|Ketol-acid reductoisomerase 3D structures]]
 == References ==
 <references/>
 __TOC__
 </StructureSection>
-[[Category: Ketol-acid reductoisomerase]]
+[[Category: Large Structures]]
-[[Category: Chen, C Y]]
+[[Category: Sulfolobus acidocaldarius]]
-[[Category: Chiang, C H]]
+[[Category: Chen CY]]
-[[Category: Horng, J C]]
+[[Category: Chiang CH]]
-[[Category: Huang, C H]]
+[[Category: Horng JC]]
-[[Category: Ko, T P]]
+[[Category: Huang CH]]
-[[Category: Lin, B L]]
+[[Category: Ko TP]]
-[[Category: Lin, K F]]
+[[Category: Lin BL]]
-[[Category: Tsai, M D]]
+[[Category: Lin KF]]
-[[Category: Acid tolerant enzyme]]
+[[Category: Tsai MD]]
-[[Category: Ahir]]
-[[Category: Bcaa]]
-[[Category: Biofuel]]
-[[Category: Branched-chain amino acid]]
-[[Category: Isomerase]]
-[[Category: Knot domain]]
-[[Category: Metal ion cofactor]]
-[[Category: Nadh]]
-[[Category: Nadph]]
-[[Category: Reductase]]

5yeq

From Proteopedia

Current revision

The structure of Sac-KARI protein

Structural highlights

Function

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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