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1qjz
From Proteopedia
(New page: 200px<br /><applet load="1qjz" size="450" color="white" frame="true" align="right" spinBox="true" caption="1qjz, resolution 3.8Å" /> '''THREE DIMENSIONAL STR...) |
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| - | [[Image:1qjz.gif|left|200px]]<br /><applet load="1qjz" size=" | + | [[Image:1qjz.gif|left|200px]]<br /><applet load="1qjz" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1qjz, resolution 3.8Å" /> | caption="1qjz, resolution 3.8Å" /> | ||
'''THREE DIMENSIONAL STRUCTURE OF PHYSALIS MOTTLE VIRUS: IMPLICATIONS FOR THE VIRAL ASSEMBLY'''<br /> | '''THREE DIMENSIONAL STRUCTURE OF PHYSALIS MOTTLE VIRUS: IMPLICATIONS FOR THE VIRAL ASSEMBLY'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The structure of the T=3 single stranded RNA tymovirus, physalis mottle | + | The structure of the T=3 single stranded RNA tymovirus, physalis mottle virus (PhMV), has been determined to 3.8 A resolution. PhMV crystals belong to the rhombohedral space group R 3, with one icosahedral particle in the unit cell leading to 20-fold non-crystallographic redundancy. Polyalanine coordinates of the related turnip yellow mosaic virus (TYMV) with which PhMV coat protein shares 32 % amino acid sequence identity were used for obtaining the initial phases. Extensive phase refinement by real space molecular replacement density averaging resulted in an electron density map that revealed density for most of the side-chains and for the 17 residues ordered in PhMV, but not seen in TYMV, at the N terminus of the A subunits. The core secondary and tertiary structures of the subunits have a topology consistent with the capsid proteins of other T=3 plant viruses. The N-terminal arms of the A subunits, which constitute 12 pentamers at the icosahedral 5-fold axes, have a conformation very different from the conformations observed in B and C subunits that constitute hexameric capsomers with near 6-fold symmetry at the icosahedral 3-fold axes. An analysis of the interfacial contacts between protein subunits indicates that the hexamers are held more strongly than pentamers and hexamer-hexamer contacts are more extensive than pentamer-hexamer contacts. These observations suggest a plausible mechanism for the formation of empty capsids, which might be initiated by a change in the conformation of the N-terminal arm of the A subunits. The structure also provides insights into immunological and mutagenesis results. Comparison of PhMV with the sobemovirus, sesbania mosaic virus reveals striking similarities in the overall tertiary fold of the coat protein although the capsid morphologies of these two viruses are very different. |
==About this Structure== | ==About this Structure== | ||
| - | 1QJZ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Physalis_mottle_virus Physalis mottle virus]. Full crystallographic information is available from [http:// | + | 1QJZ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Physalis_mottle_virus Physalis mottle virus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QJZ OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Physalis mottle virus]] | [[Category: Physalis mottle virus]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Hiremath, C | + | [[Category: Hiremath, C N.]] |
| - | [[Category: Krishna, S | + | [[Category: Krishna, S S.]] |
| - | [[Category: Munshi, S | + | [[Category: Munshi, S K.]] |
| - | [[Category: Murthy, M | + | [[Category: Murthy, M R.N.]] |
[[Category: Prahadeeswaran, D.]] | [[Category: Prahadeeswaran, D.]] | ||
[[Category: Sastri, M.]] | [[Category: Sastri, M.]] | ||
| - | [[Category: Savithri, H | + | [[Category: Savithri, H S.]] |
[[Category: coat protein (viral)]] | [[Category: coat protein (viral)]] | ||
[[Category: icosahedral virus]] | [[Category: icosahedral virus]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:40:28 2008'' |
Revision as of 12:40, 21 February 2008
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THREE DIMENSIONAL STRUCTURE OF PHYSALIS MOTTLE VIRUS: IMPLICATIONS FOR THE VIRAL ASSEMBLY
Overview
The structure of the T=3 single stranded RNA tymovirus, physalis mottle virus (PhMV), has been determined to 3.8 A resolution. PhMV crystals belong to the rhombohedral space group R 3, with one icosahedral particle in the unit cell leading to 20-fold non-crystallographic redundancy. Polyalanine coordinates of the related turnip yellow mosaic virus (TYMV) with which PhMV coat protein shares 32 % amino acid sequence identity were used for obtaining the initial phases. Extensive phase refinement by real space molecular replacement density averaging resulted in an electron density map that revealed density for most of the side-chains and for the 17 residues ordered in PhMV, but not seen in TYMV, at the N terminus of the A subunits. The core secondary and tertiary structures of the subunits have a topology consistent with the capsid proteins of other T=3 plant viruses. The N-terminal arms of the A subunits, which constitute 12 pentamers at the icosahedral 5-fold axes, have a conformation very different from the conformations observed in B and C subunits that constitute hexameric capsomers with near 6-fold symmetry at the icosahedral 3-fold axes. An analysis of the interfacial contacts between protein subunits indicates that the hexamers are held more strongly than pentamers and hexamer-hexamer contacts are more extensive than pentamer-hexamer contacts. These observations suggest a plausible mechanism for the formation of empty capsids, which might be initiated by a change in the conformation of the N-terminal arm of the A subunits. The structure also provides insights into immunological and mutagenesis results. Comparison of PhMV with the sobemovirus, sesbania mosaic virus reveals striking similarities in the overall tertiary fold of the coat protein although the capsid morphologies of these two viruses are very different.
About this Structure
1QJZ is a Single protein structure of sequence from Physalis mottle virus. Full crystallographic information is available from OCA.
Reference
Three-dimensional structure of physalis mottle virus: implications for the viral assembly., Krishna SS, Hiremath CN, Munshi SK, Prahadeeswaran D, Sastri M, Savithri HS, Murthy MR, J Mol Biol. 1999 Jun 18;289(4):919-34. PMID:10369772
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