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2aro
From Proteopedia
(New page: 200px<br /><applet load="2aro" size="450" color="white" frame="true" align="right" spinBox="true" caption="2aro, resolution 2.10Å" /> '''Crystal Structure Of...) |
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| - | [[Image:2aro.gif|left|200px]]<br /><applet load="2aro" size=" | + | [[Image:2aro.gif|left|200px]]<br /><applet load="2aro" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="2aro, resolution 2.10Å" /> | caption="2aro, resolution 2.10Å" /> | ||
'''Crystal Structure Of The Native Histone Octamer To 2.1 Angstrom Resolution, Crystalised In The Presence Of S-Nitrosoglutathione'''<br /> | '''Crystal Structure Of The Native Histone Octamer To 2.1 Angstrom Resolution, Crystalised In The Presence Of S-Nitrosoglutathione'''<br /> | ||
==Overview== | ==Overview== | ||
| - | A H3 dimer band is produced when purified native histone octamers are run | + | A H3 dimer band is produced when purified native histone octamers are run on an SDS-PAGE gel in a beta-mercaptoethanol-free environment. To investigate this, native histone octamer crystals, derived from chicken erythrocytes, and of structure (H2A-H2B)-(H4-H3)-(H3'-H4')-(H2B'-H2A'), were grown in 2 M KCl, 1.35 M potassium phosphates and 250-350 microM of the oxidising agent S-nitrosoglutathione, pH 6.9. X-ray diffraction data were acquired to 2.10 A resolution, yielding a structure with an Rwork value of 18.6% and an Rfree of 22.5%. The space group is P6(5), the asymmetric unit of which contains one complete octamer. Compared to the 1.90 A resolution, unoxidised native histone octamer structure, the crystals show a reduction of 2.5% in the c-axis of the unit cell, and free-energy calculations reveal that the H3-H3' dimer interface in the latter has become thermodynamically stable, in contrast to the former. Although the inter-sulphur distance of the two H3 cysteines in the oxidised native histone octamer has reduced to 6 A from the 7 A of the unoxidised form, analysis of the hydrogen bonds that constitute the (H4-H3)-(H3'-H4') tetramer indicates that the formation of a disulphide bond in the H3-H3' dimer interface is incompatible with stable tetramer formation. The biochemical and biophysical evidence, taken as a whole, is indicative of crystals that have a stable H3-H3' dimer interface, possibly extending to the interface within an isolated H3-H3' dimer, observed in SDS-PAGE gels. |
==About this Structure== | ==About this Structure== | ||
| - | 2ARO is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Gallus_gallus Gallus gallus] with PO4 and CL as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 2ARO is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Gallus_gallus Gallus gallus] with <scene name='pdbligand=PO4:'>PO4</scene> and <scene name='pdbligand=CL:'>CL</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2ARO OCA]. |
==Reference== | ==Reference== | ||
| Line 13: | Line 13: | ||
[[Category: Gallus gallus]] | [[Category: Gallus gallus]] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
| - | [[Category: Baldwin, J | + | [[Category: Baldwin, J P.]] |
| - | [[Category: Lambert, S | + | [[Category: Lambert, S J.]] |
| - | [[Category: Nicholson, J | + | [[Category: Nicholson, J M.]] |
| - | [[Category: Reynolds, C | + | [[Category: Reynolds, C D.]] |
[[Category: Sodngam, S.]] | [[Category: Sodngam, S.]] | ||
| - | [[Category: Wood, C | + | [[Category: Wood, C M.]] |
[[Category: CL]] | [[Category: CL]] | ||
[[Category: PO4]] | [[Category: PO4]] | ||
| Line 26: | Line 26: | ||
[[Category: oxidation]] | [[Category: oxidation]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:30:17 2008'' |
Revision as of 14:30, 21 February 2008
|
Crystal Structure Of The Native Histone Octamer To 2.1 Angstrom Resolution, Crystalised In The Presence Of S-Nitrosoglutathione
Overview
A H3 dimer band is produced when purified native histone octamers are run on an SDS-PAGE gel in a beta-mercaptoethanol-free environment. To investigate this, native histone octamer crystals, derived from chicken erythrocytes, and of structure (H2A-H2B)-(H4-H3)-(H3'-H4')-(H2B'-H2A'), were grown in 2 M KCl, 1.35 M potassium phosphates and 250-350 microM of the oxidising agent S-nitrosoglutathione, pH 6.9. X-ray diffraction data were acquired to 2.10 A resolution, yielding a structure with an Rwork value of 18.6% and an Rfree of 22.5%. The space group is P6(5), the asymmetric unit of which contains one complete octamer. Compared to the 1.90 A resolution, unoxidised native histone octamer structure, the crystals show a reduction of 2.5% in the c-axis of the unit cell, and free-energy calculations reveal that the H3-H3' dimer interface in the latter has become thermodynamically stable, in contrast to the former. Although the inter-sulphur distance of the two H3 cysteines in the oxidised native histone octamer has reduced to 6 A from the 7 A of the unoxidised form, analysis of the hydrogen bonds that constitute the (H4-H3)-(H3'-H4') tetramer indicates that the formation of a disulphide bond in the H3-H3' dimer interface is incompatible with stable tetramer formation. The biochemical and biophysical evidence, taken as a whole, is indicative of crystals that have a stable H3-H3' dimer interface, possibly extending to the interface within an isolated H3-H3' dimer, observed in SDS-PAGE gels.
About this Structure
2ARO is a Protein complex structure of sequences from Gallus gallus with and as ligands. Full crystallographic information is available from OCA.
Reference
The oxidised histone octamer does not form a H3 disulphide bond., Wood CM, Sodngam S, Nicholson JM, Lambert SJ, Reynolds CD, Baldwin JP, Biochim Biophys Acta. 2006 Aug;1764(8):1356-62. Epub 2006 Jul 21. PMID:16920041
Page seeded by OCA on Thu Feb 21 16:30:17 2008
Categories: Gallus gallus | Protein complex | Baldwin, J P. | Lambert, S J. | Nicholson, J M. | Reynolds, C D. | Sodngam, S. | Wood, C M. | CL | PO4 | Allostery | Circular dichroism | Octamer | Oxidation
