2ARO

Crystal Structure Of The Native Histone Octamer To 2.1 Angstrom Resolution, Crystalised In The Presence Of S-Nitrosoglutathione

Summary for 2ARO

• Entry DOI: 10.2210/pdb2aro/pdb
• Related: 1HQ3 1TZY
• Descriptor: Histone H2A-IV, Histone H2B, HISTONE H3, ... (7 entities in total)
• Functional Keywords: octamer, oxidation, allostery, circular dichroism, structural protein
• Biological source: Gallus gallus (chicken); More
• Cellular location: Nucleus: P02263 P84229 P62801
• Total number of polymer chains: 8
• Total formula weight: 110766.56

Authors

Wood, C.M.,Sodngam, S.,Nicholson, J.M.,Lambert, S.J.,Reynolds, C.D.,Baldwin, J.P. (deposition date: 2005-08-20, release date: 2005-08-30, Last modification date: 2023-08-23)

Primary citation

Wood, C.M.,Sodngam, S.,Nicholson, J.M.,Lambert, S.J.,Reynolds, C.D.,Baldwin, J.P.
The oxidised histone octamer does not form a H3 disulphide bond.
Biochim.Biophys.Acta, 1764:1356-1362, 2006

PubMed Abstract: 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.

PubMed: 16920041
DOI: 10.1016/j.bbapap.2006.06.014

Experimental method

X-RAY DIFFRACTION (2.1 Å)