= Solution
\b[Experiment 2:] relative to untreated wild-type <actin>, <actin monomer sequestration> predicts a longer apparent <actin nucleation> lag, a smaller elongation slope, and a lower steady-state <polymer> mass. At sufficiently strong binding the trace could remain nearly flat rather than displaying clearly separated phases. The wild-type <sedimentation> data support a lower endpoint, but do not establish the exact kinetic changes or whether the time to plateau is longer or shorter.
\b[Experiment 3:] the halo result does not determine the drug-free <actin polymerization> curve of act1-129. A <mutation> that mainly raises drug affinity could have a nearly wild-type curve without drug. A <mutation> that intrinsically destabilizes <actin filaments> or impairs <actin nucleation> could instead prolong the lag, reduce growth and lower the plateau. Thus a wild-type-like untreated curve is a useful conditional reference prediction, not a result that follows from cellular hypersensitivity.
\b[Experiment 4:] act1-129 is about sixfold more sensitive in the cellular assay. If that reflects a stronger direct effect of ToxB on its <actin monomers>, predict greater suppression than in experiment 2: a longer or effectively absent <actin nucleation> phase, slower or undetectable elongation, and a still lower plateau relative to its own drug-free control. It could be almost flat. However, cellular hypersensitivity could also arise from reduced functional reserve or altered interactions with other <proteins>; it does not guarantee stronger inhibition of purified <actin>. These alternatives are exactly what the comparison with experiment 3 resolves. No numerical lag, slope or plateau can be calculated from halo sizes alone.
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