 |
PDBsum entry 2aro
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Structural protein
|
PDB id
|
|
|
|
2aro
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
Contents |
 |
|
|
|
|
|
|
|
|
|
|
|
106 a.a.
|
|
|
|
|
|
|
|
|
|
|
92 a.a.
|
|
|
|
|
|
|
|
|
|
|
95 a.a.
|
|
|
|
|
|
|
|
|
|
|
83 a.a.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
References listed in PDB file
|
|
|
Key reference
|
|
|
Title
|
|
The oxidised histone octamer does not form a h3 disulphide bond.
|
|
|
Authors
|
|
C.M.Wood,
S.Sodngam,
J.M.Nicholson,
S.J.Lambert,
C.D.Reynolds,
J.P.Baldwin.
|
|
|
Ref.
|
|
Biochim Biophys Acta, 2006,
1764,
1356-1362.
|
|
|
PubMed id
|
|
|
|
|
|
|
|
|
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.
|
|
|
|
|
|
|
