See on Scoop.it – Virology and Bioinformatics from Virology.ca
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: https://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
ViroBlogy 
11 September, 2013 at 18:14 |
I just wanted to say how much I enjoy Viroblogy. You really cover some very interesting topics. Concerning viral structure, are the human filoviruses the only human viral pathogens that are long and “stringy”? They remind me a little of tobacco mosaic virus. Just wondering. Thanks
12 September, 2013 at 12:49 |
Hi Linda: thanks! Much appreciated. I have fun doing it, too.
Yes, filoviruses are the only long stringy ones – although both HBV and flu viruses can form tubes as well, these are not virions.
12 September, 2013 at 14:09
Thank you for your comments. I’m very intrigued about the possibility that perhaps plant viruses could (and have in cell culture) infect animal cells. Who knows what possibilities might exist? Maybe viroids would be more likely to do so. ?? There may be more genetic shuffling going on than we imagine. Just thinking…
Anyway, you do a great service by bringing our attention to these interesting topics. Thank you.
17 September, 2013 at 17:14
There have been a number of attempts to infect animal cells with plant viruses, which have been unsuccessful.
And yet, and yet…reticulocyte lysates quite happily translate plant virus genomic ss+RNAs, and yeasts have been shown (with some help) to support replication of +RNAs as well as of geminiviruses (and papillomaviruses for that matter).
So who knows??