 |
PDBsum entry 2gnu
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Photosynthesis
|
PDB id
|
|
|
|
2gnu
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
 |
Contents |
 |
|
|
|
|
|
|
|
|
|
|
|
235 a.a.
|
|
|
|
|
|
|
|
|
|
|
281 a.a.
|
|
|
|
|
|
|
|
|
|
|
300 a.a.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
References listed in PDB file
|
|
|
Key reference
|
|
|
Title
|
|
Lipidic sponge phase crystallization of membrane proteins.
|
|
|
Authors
|
|
P.Wadsten,
A.B.Wöhri,
A.Snijder,
G.Katona,
A.T.Gardiner,
R.J.Cogdell,
R.Neutze,
S.Engström.
|
|
|
Ref.
|
|
J Mol Biol, 2006,
364,
44-53.
[DOI no: ]
|
|
|
PubMed id
|
|
|
|
|
|
Abstract
|
|
|
Bicontinuous lipidic cubic phases can be used as a host for growing crystals of
membrane proteins. Since the cubic phase is stiff, handling is difficult and
time-consuming. Moreover, the conventional cubic phase may interfere with the
hydrophilic domains of membrane proteins due to the limited size of the aqueous
pores. Here, we introduce a new crystallization method that makes use of a
liquid analogue of the cubic phase, the sponge phase. This phase facilitates a
considerable increase in the allowed size of aqueous domains of membrane
proteins, and is easily generalised to a conventional vapour diffusion
crystallisation experiment, including the use of nanoliter drop crystallization
robots. The appearance of the sponge phase was confirmed by visual inspection,
small-angle X-ray scattering and NMR spectroscopy. Crystals of the reaction
centre from Rhodobacter sphaeroides were obtained by a conventional hanging-drop
experiment, were harvested directly without the addition of lipase or
cryoprotectant, and the structure was refined to 2.2 Angstroms resolution. In
contrast to our earlier lipidic cubic phase reaction centre structure, the
mobile ubiquinone could be built and refined. The practical advantages of the
sponge phase make it a potent tool for crystallization of membrane proteins.
|
|
|
|
|
|
|
|
Figure 2.
Figure 2. Crystals grown directly from the L[3] phase using
MO and buffer solution. (a) RC crystal fished directly from the
L[3] phase. (b) and (c) Crystals of RC grown in 20% jeffamine
M600 (pH 8.1).
|
|
Figure 4.
Figure 4. Q[B] binding sites of RCsph. All pictures are
represented in stereoview. (a) Arrangement of the cofactors Q[A]
and Q[B], subunits H, L, M and the location of the membrane in
RCsph. The colouring scheme is: H, L, M subunit (dark grey),
cofactors Q[A] (red), Q[B] (orange). The approximate position of
the membrane is indicated by the light grey square. (b) Refined
electron density for the Q[B] binding pocket. The 2F[o] – F[c]
map is contoured at 1σ. (c) Simulated-annealing omit map
omitting Q[B] contoured at 1σ. (d) Superposition of ubiquinone
in the Q[B] binding pocket. Colour code and PDB entries: red,
1YST;^43 light green, 1AIG;^45 dark green, 1AIJ;^45 blue,
1RG5;^44 orange, present structure 2GNU.
|
|
|
|
|
|
The above figures are
reprinted
by permission from Elsevier:
J Mol Biol
(2006,
364,
44-53)
copyright 2006.
|
|
|
|
|
|
|
