1f5f
From Proteopedia
(New page: 200px<br /> <applet load="1f5f" size="450" color="white" frame="true" align="right" spinBox="true" caption="1f5f, resolution 1.7Å" /> '''CRYSTAL STRUCTURE OF...) |
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| - | [[Image:1f5f.gif|left|200px]]<br /> | + | [[Image:1f5f.gif|left|200px]]<br /><applet load="1f5f" size="350" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="1f5f" size=" | + | |
caption="1f5f, resolution 1.7Å" /> | caption="1f5f, resolution 1.7Å" /> | ||
'''CRYSTAL STRUCTURE OF THE N-TERMINAL G-DOMAIN OF SHBG IN COMPLEX WITH ZINC'''<br /> | '''CRYSTAL STRUCTURE OF THE N-TERMINAL G-DOMAIN OF SHBG IN COMPLEX WITH ZINC'''<br /> | ||
==Overview== | ==Overview== | ||
| - | One calcium-binding site (site I) and a second poorly defined | + | One calcium-binding site (site I) and a second poorly defined metal-binding site (site II) have been observed previously within the amino-terminal laminin G-like domain (G domain) of human sex hormone-binding globulin (SHBG). By soaking crystals of this structure in 2.5 mm ZnCl(2), site II and a new metal-binding site (site III) were found to bind Zn(2+). Site II is located close to the steroid-binding site, and Zn(2+) is coordinated by the side chains of His(83) and His(136) and the carboxylate group of Asp(65). In this site, Zn(2+) prevents Asp(65) from interacting with the steroid 17beta-hydroxy group and alters the conformations of His(83) and His(136), as well as a disordered region over the steroid-binding site. Site III is formed by the side chains of His(101) and the carboxylate group of Asp(117), and the distance between them (2.7 A) is increased to 3.7 A in the presence of Zn(2+). The affinity of SHBG for estradiol is reduced in the presence of 0. 1-1 mm Zn(2+), whereas its affinity for androgens is unchanged, and chemically-related metal ions (Cd(2+) and Hg(2+)) have similar but less pronounced effects. This is not observed when Zn(2+) coordination at site II is modified by substituting Gln for His(136). An alteration in the steroid-binding specificity of human SHBG by Zn(2+) occupancy of site II may be relevant in male reproductive tissues where zinc concentrations are very high. |
==About this Structure== | ==About this Structure== | ||
| - | 1F5F is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with CA, ZN, DHT and IPA as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1F5F is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with <scene name='pdbligand=CA:'>CA</scene>, <scene name='pdbligand=ZN:'>ZN</scene>, <scene name='pdbligand=DHT:'>DHT</scene> and <scene name='pdbligand=IPA:'>IPA</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1F5F OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Avvakumov, V | + | [[Category: Avvakumov, V A.]] |
| - | [[Category: Hammond, G | + | [[Category: Hammond, G L.]] |
| - | [[Category: Muller, Y | + | [[Category: Muller, Y A.]] |
[[Category: CA]] | [[Category: CA]] | ||
[[Category: DHT]] | [[Category: DHT]] | ||
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[[Category: jellyroll]] | [[Category: jellyroll]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:35:06 2008'' |
Revision as of 10:35, 21 February 2008
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CRYSTAL STRUCTURE OF THE N-TERMINAL G-DOMAIN OF SHBG IN COMPLEX WITH ZINC
Overview
One calcium-binding site (site I) and a second poorly defined metal-binding site (site II) have been observed previously within the amino-terminal laminin G-like domain (G domain) of human sex hormone-binding globulin (SHBG). By soaking crystals of this structure in 2.5 mm ZnCl(2), site II and a new metal-binding site (site III) were found to bind Zn(2+). Site II is located close to the steroid-binding site, and Zn(2+) is coordinated by the side chains of His(83) and His(136) and the carboxylate group of Asp(65). In this site, Zn(2+) prevents Asp(65) from interacting with the steroid 17beta-hydroxy group and alters the conformations of His(83) and His(136), as well as a disordered region over the steroid-binding site. Site III is formed by the side chains of His(101) and the carboxylate group of Asp(117), and the distance between them (2.7 A) is increased to 3.7 A in the presence of Zn(2+). The affinity of SHBG for estradiol is reduced in the presence of 0. 1-1 mm Zn(2+), whereas its affinity for androgens is unchanged, and chemically-related metal ions (Cd(2+) and Hg(2+)) have similar but less pronounced effects. This is not observed when Zn(2+) coordination at site II is modified by substituting Gln for His(136). An alteration in the steroid-binding specificity of human SHBG by Zn(2+) occupancy of site II may be relevant in male reproductive tissues where zinc concentrations are very high.
About this Structure
1F5F is a Single protein structure of sequence from Homo sapiens with , , and as ligands. Full crystallographic information is available from OCA.
Reference
Steroid-binding specificity of human sex hormone-binding globulin is influenced by occupancy of a zinc-binding site., Avvakumov GV, Muller YA, Hammond GL, J Biol Chem. 2000 Aug 25;275(34):25920-5. PMID:10859323
Page seeded by OCA on Thu Feb 21 12:35:06 2008
Categories: Homo sapiens | Single protein | Avvakumov, V A. | Hammond, G L. | Muller, Y A. | CA | DHT | IPA | ZN | Jellyroll
