Mary Ann Pfannenstiel

Parameters affecting attachment of Bacillus thuringiensis var. israelensis toxin to latex beads

SummaryBacillus thuringiensis var.israelensis protein toxin radiolabeled with14C-iodoacetamide was bound to latex beads. The efficiency of attachment was not affected by the temperature or length of incubation or by the presence of several different buffers, salts, or organic solvents. However, attachment decreased dramatically at pH values >8.5 or in the presence of detergents (anionic, neutral, or cationic). Protein concentrations ≥2–3 mg/m2 of bead surface led to a progressively decreasing efficiency of protein adsorption. With minor variations, these findings should also be applicable to the attachment of numerous other proteins of diagnostic significance.