Preliminary characterization of the particles from productive and abortive infections of L cells by fowl plague virus.

Particles produced during the abortive infection of L cells by fowl plague virus (Dobson strain) have been characterized and compared to the infectious particles produced by a mutant of this virus adapted to mammalian cells. The former are of apparently normal morphology but most of them are non-infectious. They have the same RNA/protein ratio as the infectious particles and the same polypeptide composition. They contain also the same RNA segments as those found in infectious particles. Possible reasons for the defectiveness of these particles are discussed.