Isolation of single stranded DNA from purified hepatitis A-virus.

Hepatitis A-virus was purified from human stools by three purification steps. Virus was identified by radioimmunoassay and purity monitored with immune electron microscopy. Virus particles, serologically and morphologically identical, banded in CsCl in two density ranges at 1.31-1.34 g/cm3 and at 1.41-1.43 g/cm3. Virions of density 1.31-1.34 g/cm3 were shown to contain single-stranded DNA of different size classes. Class I 1.33 kb, class II 4.61 kb in addition a small amount of molecules was detected with lengths up to 15 kb.