FIG. 7.

Effects of single amino acid substitutions on BV binding to Sf9 cells. (A) Strategy for generating single amino acid substitutions in full-length GP64 constructs and insertion of constructs into the polyhedrin locus of a gp64null AcMNPV bacmid. Substituted amino acids (lowercase) are shown below wt amino acids (uppercase), and numbers represent positions in the GP64 protein. (B) Analysis of binding to Sf9 cells of labeled AcMNPV BV displaying GP64 proteins with single amino acid substitution mutations. BV were labeled with [³⁵S]methionine as described in Materials and Methods, and purified BV were analyzed for the ability to bind to Sf9 cells. Each bar represents the percent binding relative to binding by virus displaying wt GP64. The bars represent average values from three independent experiments with three replicates each. (C) (Left) Characterization of GP64 F153A and H156A mutants from purified BV by Western blot analysis with MAb B12D5. (Right) Immunoprecipitation from purified BV of [³⁵S]methionine-labeled GP64 protein containing substitutions F153A and H156A by AcV1 antibody.