A putative nucleoside triphosphate-binding domain in the nonstructural protein of B19 parvovirus is required for cytotoxicity.

Cytotoxicity secondary to B19 parvovirus infection is due to expression of the viral nonstructural protein. Nonstructural proteins of many parvoviruses contain a well-conserved nucleoside triphosphate (NTP)-binding motif, which has been shown to be essential for a variety of protein functions. We show here that cytotoxicity of the B19 parvovirus nonstructural protein was abolished by single mutations of amino acids within the NTP-binding domain, especially within the A motif, implicating NTP-binding in virus-induced cell death.