Fig. 2

Effect of initial pH and Cu²⁺ on 130 kDa ICP synthesis by B. thuringiensis X022 (arrows indicate the position of 130 kDa ICP). a Effect of initial pH as detected by SDS-PAGE. Lanes 1–6 represent pH 7.5–10.0, M protein marker; b Effect of 10⁻⁶ mol/L Cu²⁺ as detected by SDS-PAGE. Lane 1 without Cu²⁺ added, lane 2 with 10⁻⁶ mol/L Cu²⁺ added. c Effect of different concentrations of Cu²⁺ as detected by SDS-PAGE. Lanes 1–6 represent concentrations ranging from 10⁻³ to 10⁻⁸ mol/L, lane 7 without Cu²⁺ added, M protein marker. d Relative quantification of ICP production at different initial pH as analyzed with MiBio software. ICP production at pH 7.5 was set as 1.00. e Relative quantification of ICP production at different Cu²⁺ concentrations as analyzed by MiBio software. ICP production in CK (without Cu²⁺) was set as 1.00