FIG. 1.

Basic recoating parameters. “Relative infectivity” is the infectious titer of each recoating mixture divided by the infectious titer of DLPs alone. The error bars indicate the standard deviations of three titrations of each sample. The standard recoating mixture is described in Materials and Methods. Modifications to this procedure are indicated under each graph. (A) Dependence on the components of the reaction mixture. std, standard procedure; no T, not trypsin digested; EDTA, 5 mM EDTA added before trypsin digestion; 4 only, buffer alone substituted for VP7; 7 only, buffer alone substituted for VP4. (B) Dependence on pH. Recoating reaction mixtures were adjusted to the indicated pH during incubation with VP4 and VP7 (buffers are listed in Materials and Methods). (C) Temperature dependence. Temperatures during incubations with VP4 and VP7 are indicated. (D) Order of addition. VP4 and VP7 were added to the reaction mixtures in the indicated orders: 4 + 7, VP4 first; 7 + 4, VP7 with excess calcium first.