1kso
From Proteopedia
(New page: 200px<br /> <applet load="1kso" size="450" color="white" frame="true" align="right" spinBox="true" caption="1kso, resolution 1.70Å" /> '''CRYSTAL STRUCTURE O...) |
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| - | [[Image:1kso.gif|left|200px]]<br /> | + | [[Image:1kso.gif|left|200px]]<br /><applet load="1kso" size="350" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="1kso" size=" | + | |
caption="1kso, resolution 1.70Å" /> | caption="1kso, resolution 1.70Å" /> | ||
'''CRYSTAL STRUCTURE OF APO S100A3'''<br /> | '''CRYSTAL STRUCTURE OF APO S100A3'''<br /> | ||
==Overview== | ==Overview== | ||
| - | S100 proteins are involved in metal-dependent intracellular signalling. | + | S100 proteins are involved in metal-dependent intracellular signalling. Metal-free S100A3, a cysteine-rich Ca(2+)- and Zn(2+)-binding protein, has been crystallized by vapour diffusion under the strict exclusion of oxygen and in the absence of divalent metal ions. Metal binding induces large conformational changes, rendering the apo-S100A3 crystals very sensitive to various metal compounds. Therefore, the structure was solved by MIRAS phasing using potassium iodide and xenon derivatives. Iodide replaces a water molecule at the surface of the S100A3 protein, whereas xenon binds in a hydrophobic cavity at the dimer interface. Despite significant non-isomorphism, the combination of both derivatives was sufficient for structure determination. The overall apo-S100A3 structure resembles the structures of metal-free S100B and S100A6 solution structures. In contrast to the NMR structures, the EF-hand loops are well ordered in the apo-S100A3 crystal structure. In the N-terminal pseudo-EF-hand loop a water molecule occupies the position of the Ca(2+) ion. The C-terminal canonical EF-hand loop shows an extended conformation and a different helix arrangement to other S100/metal complex crystal structures. |
==About this Structure== | ==About this Structure== | ||
| - | 1KSO is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http:// | + | 1KSO is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1KSO OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Fritz, G.]] | [[Category: Fritz, G.]] | ||
| - | [[Category: Grutter, M | + | [[Category: Grutter, M G.]] |
| - | [[Category: Heizmann, C | + | [[Category: Heizmann, C W.]] |
| - | [[Category: Mittl, P | + | [[Category: Mittl, P R.E]] |
| - | [[Category: Richmond, T | + | [[Category: Richmond, T J.]] |
| - | [[Category: Sargent, D | + | [[Category: Sargent, D F.]] |
[[Category: ca2+ binding protein]] | [[Category: ca2+ binding protein]] | ||
[[Category: ef-hand]] | [[Category: ef-hand]] | ||
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[[Category: zn2+ binding protein]] | [[Category: zn2+ binding protein]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:37:32 2008'' |
Revision as of 11:37, 21 February 2008
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CRYSTAL STRUCTURE OF APO S100A3
Overview
S100 proteins are involved in metal-dependent intracellular signalling. Metal-free S100A3, a cysteine-rich Ca(2+)- and Zn(2+)-binding protein, has been crystallized by vapour diffusion under the strict exclusion of oxygen and in the absence of divalent metal ions. Metal binding induces large conformational changes, rendering the apo-S100A3 crystals very sensitive to various metal compounds. Therefore, the structure was solved by MIRAS phasing using potassium iodide and xenon derivatives. Iodide replaces a water molecule at the surface of the S100A3 protein, whereas xenon binds in a hydrophobic cavity at the dimer interface. Despite significant non-isomorphism, the combination of both derivatives was sufficient for structure determination. The overall apo-S100A3 structure resembles the structures of metal-free S100B and S100A6 solution structures. In contrast to the NMR structures, the EF-hand loops are well ordered in the apo-S100A3 crystal structure. In the N-terminal pseudo-EF-hand loop a water molecule occupies the position of the Ca(2+) ion. The C-terminal canonical EF-hand loop shows an extended conformation and a different helix arrangement to other S100/metal complex crystal structures.
About this Structure
1KSO is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Metal-free MIRAS phasing: structure of apo-S100A3., Mittl PR, Fritz G, Sargent DF, Richmond TJ, Heizmann CW, Grutter MG, Acta Crystallogr D Biol Crystallogr. 2002 Aug;58(Pt 8):1255-61. Epub 2002, Jul 20. PMID:12136135
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