Two deoxyribonuclease activities within purified vaccinia virus.

Two DNases, both hydrolizing single-stranded DNA, were identified within highly purified particles of vaccinia virus. One of these, active optimally at pH 5.0, is an exonuclease and the other, most active at pH 7.8, is an endonuclease. These two activities were localized more specifically within the virus cores. Upon elimination of the envelopes, followed by removal of the lateral bodies of vaccinia, both DNases were activated, suggesting that a specific inhibitor of these enzymes may be present in the lateral bodies.