Coat Protein‐derived Small Particles in a Tombusvirus from River Lato

Abstract

A new tombusvirus clearly distinguishable from other members of the group was isolated in Apuha from river Lato and therefore referred to as Lato River Tombusvirus (LRV). Purified virus preparations after storage for 5 months at 4 °C in 20 mM phosphate buffer, pH 7.2, contained variable amounts of small particles (c. 17 nm in diameter) in addition to typical virus particles (c. 30 nm in diameter). LKV small particles were consnruted by a single protein species with a mol. wt of 29,000, did not contain nucleic acid and were not infective but proved to be serologically undistinguisbable from ordinary virus particles. Attempts to anificially produce small particles by chemical or enzymatic treatments of full size LRV virions failed but their spontaneous production under particular storage conditions seems to be a remarkable feature of this virus as it does not occur with other definitive tombusviruses.