Abstract
Four deoxyribonucleoside monophosphokinases were studied with extracts prepared from pupae of silkworm infected and uninfected with nuclear polyhedrosis virus (NPV).
An increase in dTMP and dCMP kinase activities was observed in pupa 24 hr after the infection. The increase amounted to 2.0- and 1.5-fold, respectively. The enzymes in infected and uninfected pupae have the same pH optimum. dTMP and dCMP kinases were recovered in 35 to 50% and in 50 to 8040 ammonium sulfate fractions, respectively. Moreover, the later fraction gave also dAMP and dGMP kinase activities. However, no increase in dAMP and dGMP kinase activities was detectable in NPV-infected pupa.
The results obtained suggest that dTMP and dCMP kinases may have an important role in an early stage of the viral DNA replication.
