IDENTIFICATION OF THE PORE-FORMING ELEMENT OF SEMLIKI-FOREST-VIRUS SPIKES

Pore formation at mildly acidic pH by SFV spike proteins was investiga ted using isolated and modified virions, Modification of the virions m as performed by limited proteolysis in presence of octylglucoside and resulted in the formation of E1 particles and spikeless particles, res pectively, Pore formation mas detected by measuring the influx of prop idium iodide into the viral particles, The results obtained clearly sh owed that the presence of E1 alone is sufficient to promote pore forma tion at mildly acidic pH, Thus E1 represents the pore forming element of the viral spike proteins.