2ms2
THE REFINED STRUCTURE OF BACTERIOPHAGE MS2 AT 2.8 ANGSTROMS RESOLUTION
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OverviewOverview
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.
About this StructureAbout this Structure
2MS2 is a Single protein structure of sequence from Enterobacterio phage ms2. This structure superseeds the now removed PDB entry 1MS2. Full crystallographic information is available from OCA.
ReferenceReference
The refined structure of bacteriophage MS2 at 2.8 A resolution., Golmohammadi R, Valegard K, Fridborg K, Liljas L, J Mol Biol. 1993 Dec 5;234(3):620-39. PMID:8254664
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