3 ul and 6ul aliquots shown for all samples. The three samples on the left are PBCV purified by standard protocols. The three on the right were purfied by heating 30 min at 37 in the presence of 1mg/ml protamine sulfate (PS) or 1mg/ml of pepsin (Pep). Sample "Res" is the combined low speed pellets of the PS and Pep samples. Clearly the virus withstands acidification and pepsin digestion.
Acid pH coagulated host material which was especially apparent in the PS sample. Pepsin apparently digested the coagulated proteins leaving residual chlorophyll in the low speed supernatant. The low speed supernatant of the PS sample was opalescent and resembled purified virus.