Comparison of the Effects of Sodium Dodecyl Sulfate on Some Isometric Viruses

Abstract

Twenty-two viruses or virus strains were used in a comparison of the effects of sodium dodecyl sulfate (SDS), EDTA and MgCl2 on spherical virus particles. At pH 7, brome mosaic (BMV), broad bean mottle (BBMV), turnip crinkle (TCV), cucumber mosaic (CMV), tomato aspermy viruses (TAV) and 4 strains of cowpea chlorotic mottle virus (CCMV) were completely dissociated into protein and RNA by 0.2% SDS or less. At pH 5, all but TAV were less sensitive to SDS and 2 strains of CCMV were not dissociated in 7.5% SDS. With certain SDS concentrations, BMV, BBMV, TCV, CCMV, TAV, CMV and carnation ringspot virus (CRSV) formed components which were probably SDS-swollen virus particles. At pH 7, MgCl2 decreased the SDS sensitivity of BMV, BBMV, TCV, CCMV strains, saguaro virus and strains of CRSV. Particles of SDS-sensitive strains of CCMV and CRSV that had been reacted with formaldehyde at pH 5 were totally resistant to SDS at pH 5; at pH 7, however, they became increasingly swollen with increasing SDS concentrations. At pH 7, some particles in cucumber necrosis virus, tobacco necrosis virus and carnation mottle virus preparations were dissociated by low concentrations of SDS, but the remaining particles were not dissociated in 15% SDS. Turnip yellow mosaic virus and 2 comoviruses (echtes Ackerboennemosaik and radish mosaic viruses) were resistant to SDS in the presence of EDTA. Southern bean mosaic, tomato bushy stunt, cocksfoot mottle and sowbane mosaic viruses were resistant to SDS alone but were dissociated in SDS-EDTA solutions at pH 7.