Some Physical and Chemical Properties of Purified Poliomyelitis Virus Preparations

Columbia SK Group of Viruses

“…By comparison, the sedimentation coefficient of a 0.02 per cent suspension of purified MEF poliomyelitis virus particles is given by SCHWERDT and ScHAFFER (1955) as 154X 10-3 cmfsecfdynefgm. Assuming for Col SK virus a molecular weight of 10 million (which corresponds roughly with a sedimentation constant of 130 S), the high infectivity-protein ratio of the purified preparations leads to the conclusion that something of the order of 100 molecules represents one infectious dose.…”

Purification and Preliminary Characterization of Infantile Gastroenteritis Virus (Orbivirus Group)

“…Negative contrast electron microscopy of this fraction revealed IGV like those shown in figure IB. Since reovirus has a sedimentation coefficient of 630S and poliovirus of 160S, our calculated sedimentation coefficient of IGV lies between 520 and 530S [8,9].…”

Some Applications of Detergents to the Study of the Virus of Foot-and-Mouth Disease

“…In recent years methods have been developed for the concentration of polio virus from large volumes of tissue culture fluids (Schwerdt & Schaffer, 1955) but in this case the very favourable stability properties of the virus have enabled co-precipitation with the proteins of the medium at pH 4.0-4.5 to be used as an initial concentration step. The extreme lability of the virus of foot-and-mouth disease a t low pH values precludes the use of this method, and the methods a t present being used for the concentration of this virus (precipitation with ammonium sulphate, ethanol or acetone after deproteinization with chloroform, Pyl & Rohrer, 1955 ; or protamine, Hansen & Holm, 1950 ; and ultracentrifugation) although useful for concentration from sources of low volume are not well suited for use on a large scale.…”