Fig. 3. Point mutations affect different steps along the Cyt1Aa bioactivation cascade.

For each row, different letters indicate significant differences between mutants. ¹Length and ²width of crystals. ³Productivity was visually estimated based on the quantity and aspect of the crystal-spore suspension collected. ⁴SP₅₀ corresponds to the concentration at which 50% of crystals solubilize after 1 h incubation at RT. See Supplementary Table 2 for corresponding statistics. ⁵Protoxin solubilized without DTT, releasing a disulfide-bridged dimer (except for C7S), and ⁶with DTT, releasing a protoxin monomer. ⁷Toxin monomer activated by proteinase K. ⁸Capacity of each toxin species to generate a ladder pattern characteristic of membrane-bound oligomers (MBO) on 6% SDS-PAGE. See corresponding gels in Supplementary Fig. 9. ⁹LC₅₀ corresponds to the concentration lethal for 50% of cell population. See Supplementary Table 2 for corresponding statistics. Scale bar = 0.2 µm. Source data are provided as a Source Data file.