Protein cleavage and poxvirus morphogenesis: Tryptic peptide analysis of core precursors accumulated by blocking assembly with rifampicin

Rifampicin was used to block vaccinia virus assembly and accumulate structural proteins that have not undergone maturational processing. Two of these proteins were purified and shown by tryptic peptide analysis to be higher molecular weight precursors of the major core components. In contrast, rifampicin did not prevent the formation from its precursor of another virion protein located outside the virus core.