Improved Purification of Two Potato Carlaviruses

Publisher Website
Google Scholar
Abstract
EM examinations of potato virus M (PVM), and potato virus S (PVS), purified by procedures employing clarification with organic solvents, revealed that virus preparations were unsuitable for characterization studies because of extensive fragmentation of the particles. Considerably higher virus yields and percentages of intact particles were obtained by a new purification scheme that entailed sap clarification with calcium phosphate, polyethylene glycol precipitation, 2 cycles of differential centrifugation using sucrose cushions, rate zonal centrifugation in sucrose and equilibrium centrifugation in Cs2SO4. The estimated yield of PVM, obtained from equilibrium density gradient zones was 46 .+-. 9 .mu.g of virus/g of tissue; that of PVS was 31 .+-. 6 .mu.g of virus/g of tissue. Purified PVM or PVS behaved as homogeneous systems in sedimentation-velocity experiments.