Barley stripe mosaic virus (BSMV) is the type member of the genus Hordeivirus, rigid, rod-shaped viruses in the family Virgaviridae. We have used fiber diffraction and cryo-electron microscopy to determine the helical symmetry of BSMV to be 23.2 subunits per turn of the viral helix, and to obtain a low-resolution model of the virus by helical reconstruction methods. Features in the model support a structural relationship between the coat proteins of the hordeiviruses and the tobamoviruses.
Speaking as someone who has worked with both viruses – I think I purified them in 1977-78 – and was immersed in the literature on both, I can recommend this as an EXCELLENT piece of old-school structural virology.
It comes as litttle surprise to hear that BSMV CP is structurally related to TMV and its ilk – the particles look SO much alike – but it is nice to see it confirmed finally! The TMV structure came out in 1986, again from Gerald Stubbs’ lab (and some beautiful structures are shown here - http://www.rcsb.org/pdb/101/motm.do?momID=109), so this one has been lagging awhile.
I can finally update a speculative "modular evolution" diagram I constructed a while back, with actual evidence: http://rybicki.wordpress.com/2008/03/19/from-what-did-viruses-evolve-or-how-did-they-initially-arise/
Meantime: I have a walk-in fridge full of highly purified virus particles, some dating back to the 1970s, just waiting to be structurally investigated….
See on www.sciencedirect.com