Fig 3.

Analysis of the binding of MMA-tet with the Stx1 B subunit. (A) The binding between MMA-tet and a series of 1BH mutants (10 μg/ml) was examined using the AlphaScreen assay. Data are presented as signal intensity (cps). Each experiment was performed three times, and representative data are shown. (B) The binding of 1BH (1 μg/ml) with MMA-tet or Ala-substituted MMA-tet was examined using ELISA (mean ± standard error, n = 3; *, P < 0.001, Tukey's test). R4A, R5A, R6A, and R7A, MMA-tet with a substitution of Arg to Ala at positions 4, 5, 6, and 7, respectively. OD₄₉₀, optical density at 490 nm.