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1mrq
From Proteopedia
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|PDB= 1mrq |SIZE=350|CAPTION= <scene name='initialview01'>1mrq</scene>, resolution 1.59Å | |PDB= 1mrq |SIZE=350|CAPTION= <scene name='initialview01'>1mrq</scene>, resolution 1.59Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand= | + | |LIGAND= <scene name='pdbligand=BME:BETA-MERCAPTOETHANOL'>BME</scene>, <scene name='pdbligand=NAP:NADP+NICOTINAMIDE-ADENINE-DINUCLEOTIDE+PHOSPHATE'>NAP</scene>, <scene name='pdbligand=STR:PROGESTERONE'>STR</scene> |
| - | |ACTIVITY= [http://en.wikipedia.org/wiki/20-alpha-hydroxysteroid_dehydrogenase 20-alpha-hydroxysteroid dehydrogenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.1.1.149 1.1.1.149] | + | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/20-alpha-hydroxysteroid_dehydrogenase 20-alpha-hydroxysteroid dehydrogenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.1.1.149 1.1.1.149] </span> |
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY= | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1mrq FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1mrq OCA], [http://www.ebi.ac.uk/pdbsum/1mrq PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1mrq RCSB]</span> | ||
}} | }} | ||
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==Overview== | ==Overview== | ||
Human 20alpha-hydroxysteroid dehydrogenase (h20alpha-HSD; AKR1C1) catalyzes the transformation of progesterone (Prog) into 20alpha-hydroxy-progesterone (20alpha-OHProg). Although h20alpha-HSD shares 98% sequence identity with human type 3 3alpha-HSD (h3alpha-HSD3, AKR1C2), these two enzymes differ greatly in their activities. In order to explain these differences, we have solved the crystal structure of h20alpha-HSD in a ternary complex with NADP(+) and 20alpha-OHProg at 1.59A resolution. The steroid is stabilized by numerous hydrophobic interactions and a hydrogen bond between its O20 and the N(epsilon ) atom of His222. This new interaction prevents the formation of a hydrogen bond with the cofactor, as seen in h3alpha-HSD3 ternary complexes. By combining structural, direct mutagenesis and kinetic studies, we found that the H(222)I substitution decreases the K(m) value for the cofactor 95-fold. With these results, we hypothesize that the rotation of the lateral chain of His222 could be a mediating step between the transformation of Prog and the release of the cofactor. Moreover, crystal structure analysis and direct mutagenesis experiments lead us to identify a new residue involved in the binding of Prog. Indeed, the R(304)L substitution leads to a 65-fold decrease in the K(m) value for Prog reduction. We thus propose that Prog is maintained in a new steroid-binding site composed mainly of residues found in the carboxy-terminal region of the protein. | Human 20alpha-hydroxysteroid dehydrogenase (h20alpha-HSD; AKR1C1) catalyzes the transformation of progesterone (Prog) into 20alpha-hydroxy-progesterone (20alpha-OHProg). Although h20alpha-HSD shares 98% sequence identity with human type 3 3alpha-HSD (h3alpha-HSD3, AKR1C2), these two enzymes differ greatly in their activities. In order to explain these differences, we have solved the crystal structure of h20alpha-HSD in a ternary complex with NADP(+) and 20alpha-OHProg at 1.59A resolution. The steroid is stabilized by numerous hydrophobic interactions and a hydrogen bond between its O20 and the N(epsilon ) atom of His222. This new interaction prevents the formation of a hydrogen bond with the cofactor, as seen in h3alpha-HSD3 ternary complexes. By combining structural, direct mutagenesis and kinetic studies, we found that the H(222)I substitution decreases the K(m) value for the cofactor 95-fold. With these results, we hypothesize that the rotation of the lateral chain of His222 could be a mediating step between the transformation of Prog and the release of the cofactor. Moreover, crystal structure analysis and direct mutagenesis experiments lead us to identify a new residue involved in the binding of Prog. Indeed, the R(304)L substitution leads to a 65-fold decrease in the K(m) value for Prog reduction. We thus propose that Prog is maintained in a new steroid-binding site composed mainly of residues found in the carboxy-terminal region of the protein. | ||
| - | |||
| - | ==Disease== | ||
| - | Known disease associated with this structure: Obesity, hyperphagia, and developmental delay OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=600450 600450]] | ||
==About this Structure== | ==About this Structure== | ||
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[[Category: Legrand, P.]] | [[Category: Legrand, P.]] | ||
[[Category: Luu-The, V.]] | [[Category: Luu-The, V.]] | ||
| - | [[Category: BME]] | ||
| - | [[Category: NAP]] | ||
| - | [[Category: STR]] | ||
[[Category: 20alpha-hsd]] | [[Category: 20alpha-hsd]] | ||
[[Category: hydroxysteroid dehydrogenase]] | [[Category: hydroxysteroid dehydrogenase]] | ||
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[[Category: ternary complex]] | [[Category: ternary complex]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 22:20:14 2008'' |
Revision as of 19:20, 30 March 2008
| |||||||
| , resolution 1.59Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , , | ||||||
| Activity: | 20-alpha-hydroxysteroid dehydrogenase, with EC number 1.1.1.149 | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal structure of human 20alpha-HSD in ternary complex with NADP and 20alpha-hydroxy-progesterone
Overview
Human 20alpha-hydroxysteroid dehydrogenase (h20alpha-HSD; AKR1C1) catalyzes the transformation of progesterone (Prog) into 20alpha-hydroxy-progesterone (20alpha-OHProg). Although h20alpha-HSD shares 98% sequence identity with human type 3 3alpha-HSD (h3alpha-HSD3, AKR1C2), these two enzymes differ greatly in their activities. In order to explain these differences, we have solved the crystal structure of h20alpha-HSD in a ternary complex with NADP(+) and 20alpha-OHProg at 1.59A resolution. The steroid is stabilized by numerous hydrophobic interactions and a hydrogen bond between its O20 and the N(epsilon ) atom of His222. This new interaction prevents the formation of a hydrogen bond with the cofactor, as seen in h3alpha-HSD3 ternary complexes. By combining structural, direct mutagenesis and kinetic studies, we found that the H(222)I substitution decreases the K(m) value for the cofactor 95-fold. With these results, we hypothesize that the rotation of the lateral chain of His222 could be a mediating step between the transformation of Prog and the release of the cofactor. Moreover, crystal structure analysis and direct mutagenesis experiments lead us to identify a new residue involved in the binding of Prog. Indeed, the R(304)L substitution leads to a 65-fold decrease in the K(m) value for Prog reduction. We thus propose that Prog is maintained in a new steroid-binding site composed mainly of residues found in the carboxy-terminal region of the protein.
About this Structure
1MRQ is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Human 20alpha-hydroxysteroid dehydrogenase: crystallographic and site-directed mutagenesis studies lead to the identification of an alternative binding site for C21-steroids., Couture JF, Legrand P, Cantin L, Luu-The V, Labrie F, Breton R, J Mol Biol. 2003 Aug 15;331(3):593-604. PMID:12899831
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