“…They associate to form a holoenzyme complex (Frame et al, 1985;Bacchetti et al, 1986;Ingemarson & Lankinen, 1987) which is more stable than the easily dissociated subunits of the cellular reductase (Thelander et al, 1980). The synthetic YAGAVVNDL peptide, which corresponds to the carboxy-terminal nine amino acids of HSV R2, inhibits HSV RR (Dutia et al, 1986;Cohen et al, 1986a) by interfering with RI-R2 subunit interaction (Dutia et al, 1986;Cohen et al, 1986b;McClements et al, 1988;Darling et al, 1990). Thus the domain located at the C terminus of R2 is likely to be essential for subunit association.…”