View source for 6a15


==Structure of CYP90B1 in complex with cholesterol==
<StructureSection load='6a15' size='340' side='right'caption='[[6a15]], [[Resolution|resolution]] 1.79&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6a15]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Arabidopsis_thaliana Arabidopsis thaliana]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6A15 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6A15 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]] 1.79&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=CLR:CHOLESTEROL'>CLR</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</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=6a15 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6a15 OCA], [https://pdbe.org/6a15 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6a15 RCSB], [https://www.ebi.ac.uk/pdbsum/6a15 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6a15 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/C90B1_ARATH C90B1_ARATH] Catalyzes the C22-alpha-hydroxylation step in brassinosteroids biosynthesis. Converts campestanol to 6-deoxocathasterone and 6-oxocampestanol to cathasterone.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Brassinosteroids (BRs) are essential plant steroid hormones that regulate plant growth and development(1). The most potent BR, brassinolide, is produced by addition of many oxygen atoms to campesterol by several cytochrome P450 monooxygenases (CYPs). CYP90B1 (also known as DWF4) catalyses the 22(S)-hydroxylation of campesterol and is the first and rate-limiting enzyme at the branch point of the biosynthetic pathway from sterols to BRs(2). Here we show the crystal structure of Arabidopsis thaliana CYP90B1 complexed with cholesterol as a substrate. The substrate-binding conformation explains the stereoselective introduction of a hydroxy group at the 22S position, facilitating hydrogen bonding of brassinolide with the BR receptor(3-5). We also determined the crystal structures of CYP90B1 complexed with uniconazole(6,7) or brassinazole(8), which inhibit BR biosynthesis. The two inhibitors are structurally similar; however, their binding conformations are unexpectedly different. The shape and volume of the active site pocket varies depending on which inhibitor or substrate is bound. These crystal structures of plant CYPs that function as membrane-anchored enzymes and exhibit structural plasticity can inform design of novel inhibitors targeting plant membrane-bound CYPs, including those involved in BR biosynthesis, which could then be used as plant growth regulators and agrochemicals.

Structural insights into a key step of brassinosteroid biosynthesis and its inhibition.,Fujiyama K, Hino T, Kanadani M, Watanabe B, Jae Lee H, Mizutani M, Nagano S Nat Plants. 2019 Jun;5(6):589-594. doi: 10.1038/s41477-019-0436-6. Epub 2019 Jun , 10. PMID:31182839<ref>PMID:31182839</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6a15" style="background-color:#fffaf0;"></div>

==See Also==
*[[Cytochrome P450 3D structures|Cytochrome P450 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Arabidopsis thaliana]]
[[Category: Large Structures]]
[[Category: Fujiyama K]]
[[Category: Hino T]]
[[Category: Kanadani M]]
[[Category: Mizutani M]]
[[Category: Nagano S]]