Amuc_1434* amino acid sequences, expression and purification. (A) Amuc_1434* amino acid sequence. Red letters represented the conserved motifs of the aspartic protease family. (B) Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS–PAGE) analysis of the purification of protein Amuc_1434*. An aliquot of the protein after purification (70 μg/mL, left) and following a about 3-fold concentration (220 μg/mL, right) were loaded. The protein purity was higher than 95%, calculated with ImageJ software. (C) Western blot analysis of purified Amuc_1434*, loading protein were 0.6, 1 and 1.4 μg, respectively.