Hepatitis A Virus Aggregation in Suspensions of Purified Virus
Virus capsid structure as determined by x-ray crystallography or by elec imaging of virus particles in thefrozen hydrated state has received con interest during the past decade. Specific functional proteins were localized recently on the Rotavirus capsid by using cryo-electron microscopy, indicating the potential for morphological studies that rel directly to capsid protein function.Most cryo-electron microscopy studies have involved investigation of vir were 40 nm or greater in diameter. Smaller viruses may provide a greate practical difficulty in their preparation and imaging.Highly purified virus for study by x-ray crystallographic studies or ele microscopic evaluation of frozen hydrated particles requires stringent c particle aggregation. Preparations for x-ray crystallography should agg an orderly manner to form arrays and ordered crystals of sufficient size Preparations for cryo-electron microscopy are more desirable when the pa numerous but not over-lapping (Fig. 1). We have experienced uncontrolla aggregation including considerable over-lapping of hepatitis A virus (HA particles when purified preparations were stored in phosphate or tris buffers (Fig. 2).