Ribonucleoside-diphosphate reductase holoenzyme provides the precursors necessary for viral DNA synthesis. Allows virus growth in non-dividing cells. Catalyzes the biosynthesis of deoxyribonucleotides from the corresponding ribonucleotides (By similarity). [thioredoxin]-disulfide + a 2'-deoxyribonucleoside 5'-diphosphate + H2O = [thioredoxin]-dithiol + a ribonucleoside 5'-diphosphate Binds 2 iron ions per subunit. Genetic information processing; DNA replication. Heterotetramer composed of a homodimer of the large subunit (R1) and a homodimer of the small subunit (R2). Larger multisubunit protein complex are also active, composed of (R1)n(R2)n (By similarity). Expressed early in the viral replicative cycle. Belongs to the ribonucleoside diphosphate reductase small chain family.