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5cku

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Structure of Aspergillus fumigatus ornithine hydroxylase (SidA) mutant N323A bound to NADP and ornithine

Structural highlights

5cku is a 1 chain structure with sequence from Aspergillus fumigatus Af293. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 2.1Å
Ligands:	, , , ,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

SIDA_ASPFU Catalyzes the conversion of L-ornithine to N(5)-hydroxyornithine, the first step in the biosynthesis of all hydroxamate-containing siderophores, such as the secreted triacetylfusarinine C (TAFC) involved in iron uptake and the intracellular iron storage compound desferriferricrocin (DFFC). Highly specific for its substrate, only hydrolyzing l-ornithine. Has preference for NADPH over NADH, NADPH playing a role in stabilization of the C4a-hydroperoxyflavin intermediate. Essential for virulence.^[1] ^[2] ^[3] ^[4]

Publication Abstract from PubMed

The SidA ornithine N5-monooxygenase from Aspergillusfumigatus is a flavin monooxygenase that catalyzes the NADPH-dependent hydroxylation of ornithine. Herein we report a mutagenesis study targeting four residues that contact ornithine in crystal structures of SidA: Lys107, Asn293, Asn323, and Ser469. Mutation of Lys107 to Ala abolishes activity as measured in steady-state oxygen consumption and ornithine hydroxylation assays, indicating that the ionic interaction of Lys107 with the carboxylate of ornithine is essential for catalysis. Mutation of Asn293, Asn323, or Ser469 individually to Ala results in >14-fold increases in Km values for ornithine. Asn323 to Ala also increases the rate constant for flavin reduction by NADPH by 18-fold. Asn323 is unique among the four ornithine binding residues in that it also interacts with NADPH by forming a hydrogen bond with the nicotinamide ribose. The crystal structure of N323A complexed with NADP+ and ornithine shows that the nicontinamide riboside group of NADP is disordered. This result suggests that the increase in flavin reduction rate results from an increase in conformational space available to the enzyme-bound NADP(H). Asn323 thus facilitates ornithine binding at the expense of hindering flavin reduction, which demonstrates the delicate balance that exists within protein-ligand interaction networks in enzyme active sites.

Contribution to catalysis of ornithine binding residues in ornithine N5-monooxygenase.,Robinson R, Qureshi IA, Klancher CA, Rodriguez PJ, Tanner JJ, Sobrado P Arch Biochem Biophys. 2015 Sep 12;585:25-31. doi: 10.1016/j.abb.2015.09.008. PMID:26375201^[5]

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

References

↑ Schrettl M, Bignell E, Kragl C, Joechl C, Rogers T, Arst HN Jr, Haynes K, Haas H. Siderophore biosynthesis but not reductive iron assimilation is essential for Aspergillus fumigatus virulence. J Exp Med. 2004 Nov 1;200(9):1213-9. Epub 2004 Oct 25. PMID:15504822 doi:http://dx.doi.org/jem.20041242
↑ Hissen AH, Wan AN, Warwas ML, Pinto LJ, Moore MM. The Aspergillus fumigatus siderophore biosynthetic gene sidA, encoding L-ornithine N5-oxygenase, is required for virulence. Infect Immun. 2005 Sep;73(9):5493-503. PMID:16113265 doi:http://dx.doi.org/10.1128/IAI.73.9.5493-5503.2005
↑ Chocklett SW, Sobrado P. Aspergillus fumigatus SidA is a highly specific ornithine hydroxylase with bound flavin cofactor. Biochemistry. 2010 Aug 10;49(31):6777-83. doi: 10.1021/bi100291n. PMID:20614882 doi:http://dx.doi.org/10.1021/bi100291n
↑ Romero E, Fedkenheuer M, Chocklett SW, Qi J, Oppenheimer M, Sobrado P. Dual role of NADP(H) in the reaction of a flavin dependent N-hydroxylating monooxygenase. Biochim Biophys Acta. 2012 Jun;1824(6):850-7. doi: 10.1016/j.bbapap.2012.03.004. , Epub 2012 Mar 27. PMID:22465572 doi:http://dx.doi.org/10.1016/j.bbapap.2012.03.004
↑ Robinson R, Qureshi IA, Klancher CA, Rodriguez PJ, Tanner JJ, Sobrado P. Contribution to catalysis of ornithine binding residues in ornithine N5-monooxygenase. Arch Biochem Biophys. 2015 Sep 12;585:25-31. doi: 10.1016/j.abb.2015.09.008. PMID:26375201 doi:http://dx.doi.org/10.1016/j.abb.2015.09.008

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/5cku"

Categories: Aspergillus fumigatus Af293 | Large Structures | Qureshi IA | Tanner JJ

@@ Line 4: / Line 4: @@
 == Structural highlights ==
 <table><tr><td colspan='2'>[[5cku]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Aspergillus_fumigatus_Af293 Aspergillus fumigatus Af293]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5CKU OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5CKU FirstGlance]. <br>
-</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=FAD:FLAVIN-ADENINE+DINUCLEOTIDE'>FAD</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=NAP:NADP+NICOTINAMIDE-ADENINE-DINUCLEOTIDE+PHOSPHATE'>NAP</scene>, <scene name='pdbligand=ORN:L-ORNITHINE'>ORN</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]] 2.1&#8491;</td></tr>
+<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=FAD:FLAVIN-ADENINE+DINUCLEOTIDE'>FAD</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=NAP:NADP+NICOTINAMIDE-ADENINE-DINUCLEOTIDE+PHOSPHATE'>NAP</scene>, <scene name='pdbligand=ORN:L-ORNITHINE'>ORN</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=5cku FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5cku OCA], [https://pdbe.org/5cku PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5cku RCSB], [https://www.ebi.ac.uk/pdbsum/5cku PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5cku ProSAT]</span></td></tr>
 </table>

5cku

From Proteopedia

Current revision

Structure of Aspergillus fumigatus ornithine hydroxylase (SidA) mutant N323A bound to NADP and ornithine

Structural highlights

Function

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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