Figure 9.

Identification of Biotinylated Cys Proteases in Maize Apoplastic Fluid.

Apoplastic fluid from maize seedling leaves treated for 2 d with 2 mM SA was separated by anion-exchange chromatography, and fractions containing activity (17.5 to 22.5 mL) were pooled and labeled with or without DCG-04.

(A) Small-scale samples were taken and analyzed with strep-HRP.

(B) A large portion of the labeling samples was subjected to SDS-PAGE, and the corresponding bands were analyzed by MS. Identified proteases for each band are indicated in (A). Protein domain structures of the identified proteases are given in (B). All proteases contain a signal peptide, a prodomain (green), and a peptidase C1 domain (red). CP1-likeA and CP1-likeB also carry a granulin domain (blue). The active site amino acids are indicated by pink diamonds. NCBI, National Center for Biotechnology Information.