[Characteristics of the subvirion components formed after the treatment of Machupo virus with a nonionic detergent].

Machupo virus labeled with radioactive precursors of RNA or protein synthesis was purified by isodensity ultracentrifugation in sucrose concentration gradient. The purified virus was disrupted with NP-40 nonionic detergent in the presence of 1 M KCl, and subvirion fractions were separated by ultracentrifugation in urografin density gradient. This treatment resulted in formation of two subvirion components with a buoyant density 1.25-1.26 and 1.10-1.12 g/cm3 in urografin concentration gradient. The subvirion fraction with the density of 1.25-1.26 g/cm3 contained high-molecular virion RNAs, a major protein of molecular weight of 64 kD, and seemed to be the virion nucleocapsid. The solubilised fraction (1.10-1.12 g/cm3) contained glycosylated protein 37 kD which seems to be a surface glycoprotein.