M.J. Welsh and A.E. Smith, RAC Application 
Safety - The virus production lots will be assessed for sterility, general safety, and 
endotoxin. 
11. Structure and Purity of Virus 
SDS polyacrylamide gel electrophoresis of purified virions reveals a number of 
When preparations of virus were subjected to one or two additional rounds of CsCl 
centrifugation, the protein profile obtained was indistinguishable. This indicates that 
additional equilibrium centrifugation does not purify the virus further, and may suggest that 
even the less intense bands detected in the virus preparations represent minor virion 
Recombinant DNA Research, Volume 16 
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