 |
PDBsum entry 2ms2
|
|
|
|
|
 |
Contents |
 |
|
|
|
|
|
|
|
|
|
|
* Residue conservation analysis
|
|
|
|
|
References listed in PDB file
|
|
|
Key reference
|
|
|
Title
|
|
The refined structure of bacteriophage ms2 at 2.8 a resolution.
|
|
|
Authors
|
|
R.Golmohammadi,
K.Valegård,
K.Fridborg,
L.Liljas.
|
|
|
Ref.
|
|
J Mol Biol, 1993,
234,
620-639.
|
|
|
PubMed id
|
|
|
|
|
|
Abstract
|
|
|
Bacteriophage MS2 is an icosahedral virus with 180 copies of a coat protein
forming a shell around a single-stranded RNA molecule. The coat protein subunits
form a lattice with the triangulation number T = 3. The coat protein has a fold
which is different from the fold of all other viral coat proteins so far known.
It consists of a five-stranded beta sheet facing the inside of the particle, and
a hairpin and two helices on the outside. The crystal structure has been refined
at 2.8 A resolution. The final R-factor was 0.189 for reflections with F > 2
sigma, and the root-mean-square deviation from idealized bond lengths and bond
angles was 0.015 A and 2.9 degrees, respectively. The three chemically identical
conformers A, B and C are largely similar. The B conformer has a unique
conformation in one loop, which is involved in 5-fold interactions, while the A
and C conformers, which are involved in the quasi-6-fold contacts, are similar
throughout the structure. One cis-proline has been identified in the B conformer
but the corresponding prolines in A and C are of the trans isomer. This residue
is conserved within small RNA coliphages and it is proposed that this
isomerization enables a less elongated loop (FG) around the 5-fold axis, thus
creating a channel. The extensive dimer contact supports the idea of dimers as
initial building blocks. An assembly pathway is proposed where five dimers
converge into a pentamer and 12 pentamers are linked together with free dimers
creating a complete particle.
|
|
|
Secondary reference #1
|
|
|
Title
|
|
Structure determination of the bacteriophage ms2.
|
|
|
Authors
|
|
K.Valegård,
L.Liljas,
K.Fridborg,
T.Unge.
|
|
|
Ref.
|
|
Acta Crystallogr B, 1991,
47,
949-960.
|
|
|
PubMed id
|
|
|
|
|
|
|
|
|
Secondary reference #2
|
|
|
Title
|
|
The three-Dimensional structure of the bacterial virus ms2.
|
|
|
Authors
|
|
K.Valegård,
L.Liljas,
K.Fridborg,
T.Unge.
|
|
|
Ref.
|
|
Nature, 1990,
345,
36-41.
|
|
|
PubMed id
|
|
|
|
|
|
|
|
|
Secondary reference #3
|
|
|
Title
|
|
The structure of bacteriophage ms2
|
|
|
Authors
|
|
L.Liljas,
K.Valegard.
|
|
|
Ref.
|
|
semin virol, 1990,
1,
467.
|
|
|
|
Secondary reference #4
|
|
|
Title
|
|
Purification, Crystallization and preliminary X-Ray data of the bacteriophage ms2.
|
|
|
Authors
|
|
K.Valegård,
T.Unge,
I.Montelius,
B.Strandberg,
W.Fiers.
|
|
|
Ref.
|
|
J Mol Biol, 1986,
190,
587-591.
[DOI no: ]
|
|
|
PubMed id
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Figure 3.
Figure 3. Three crystal forms of the bacteriophage MS2. The cystals were produced by the vapour difFuion
echnique. (a) Type I crstals produced in hosphate buffer (pH 7.4) a 37°C; (b) type II crystals produced in Tris . HCl/
aline buffer (pH 7.4) at 19°C; (c) ype III crystals produced in phosphate buffer (pH 7.4) at 4°C. The bar represents
0.1 mm. For further crystallization details see Results.
|
|
Figure 5.
Figure 5. X-ray diffraction pattern of an MS2 crystal of type I. The X-ray photograph wa obtained by the use of an
Elliott rotating-anode X-ry generator, operated at 35 k and 55 rnA> and an Eraf-Nonius Arndt-Wonaeott camera.
he X-ray beam was filtered a,nd focused with nickel mirrors (Harrion, 1968). The crytal O,35 mm x 0.35 mm x
.15 mm, was oscillated 0.5'' around the a*-axis and the time of exposure was 20 h. The film-to-crystal distance was
90 mm giving a resolution limit of 2.6 A at the edge of the photograph.
|
|
|
|
|
|
The above figures are
reproduced from the cited reference
with permission from Elsevier
|
|
|
|
|
|
|
