FIG. 2.

Immunoblot of M. sexta BBMV solubilized proteins fractionated by SDS–8% PAGE and incubated with Cry1Ac1 wild-type and mutant toxins. The blots were developed after treatment with rabbit anti-Cry1Ac1 antibody followed by an anti-rabbit antibody–alkaline phosphatase conjugate. Lane 1, molecular mass standards (in kilodaltons); lane 2, BBMV not incubated with toxin; lane 3, BBMV incubated with wild-type toxin; lane 4, BBMV incubated with mutant toxin Q₁₃₃R; lane 5, BBMV incubated with mutant toxin I₁₃₂S; lane 6, BBMV incubated with mutant toxin I₁₃₂L; lane 7, BBMV incubated with mutant toxin I₁₃₂V; lane 8, BBMV incubated with mutant toxin I₁₃₂N; lane 9, BBMV incubated with mutant toxin A₁₆₄P. Mutant toxins R₁₃₁L and I₁₃₂V-D₁₃₆Y, with reduced toxicity, also bound to the 120-kDa BBMV protein (data not shown).