MOLECULAR CHARACTERIZATION OF NEWLY RECOGNIZED RODENT PARVOVIRUSES

Several autonomous rodent parvoviruses distinct from the prototypic ro dent parvoviruses have been isolated. These include variants of a mous e parvovirus (MPV), a hamster isolate designated hamster parvovirus (H aPV), and a variant strain of minute virus of mice (MVM) designated MV M-Cutter or MVM(c). In this study, the DNA sequence of the coding regi ons of the viral genome and the predicted protein sequences for each o f these new isolates were determined and compared to the immunosuppres sive and prototypic strains of MVM [MVMO and MVM(p)], the rodent parvo virus H-1, and LuIII, an autonomous parvovirus of uncertain host origi n. Sequence comparisons showed that the MPV isolates were almost ident ical, HaPV was very similar to MPV, and MVM(c) was most similar to MVM (i) and MVM(p). Haemagglutination inhibition assays revealed that MPV and HaPV represent two serotypes distinct from previously characterize d rodent parvovirus serotypes while MVM(c) belongs to the MVM serotype . Each of the newly isolated rodent parvoviruses was shown to encapsid ate a predominantly negative-sense 5 kb DNA genome and to encode two n onstructural proteins (NS1 and NS2) and two structural viral proteins (VP1 and VP2). These studies indicate that MPV and HaPV are autonomous parvoviruses distinct from previously characterized parvoviruses and MVM(c) is a variant strain of MVM distinct from MVM(i) and MVM(p).