sedimentation at 1g...

[Ed Rybicki]

I have just seen the results of centrifuging a TMV-U2 and a BSMV 
preparation at 1g for 26 yrs and 11 yrs, respectively...the viruses 
SEDIMENTED!!  There was a beautiful gradient in both cases, of 
uncontaminated and not-obviously-aggregated virus, from crystal clear 
ant the top of a 100 ml medical flat bottle, to thick and milky at 
the bottom - with most of the stuff at the bottom.  I am keeping one 
BSMV bottle untouched; we shook up the rest in the interests of 
scientific inquiry (we were clearing out a coldroom in preparation 
for Barbara von Wechmar's retirement at the end of the year).  BMV 
preparations left the same length of time (spherical, 30 nm, +/-100S) 
are uniformly suspended still - but rod-shaped chaps of 150-300 nm 
and +/-200S sediment beautifully.

A bit long to wait to concentrate virus tho...but so ELEGANT.

                     Ed Rybicki, PhD  
      Dept Microbiology     |  ed at molbiol.uct.ac.za   
   University of Cape Town  | phone: x27-21-650-3265
   Private Bag, Rondebosch  |  fax: x27-21-650 4023
      7700, South Africa    |   
    WWW URL: http://www.uct.ac.za/microbiology/ed.html      
                                        
"And then one day you find, ten years have got behind you"