Figure 3.

Persulfidation of Arabidopsis AtATG4a.

(A) Immunoblot analysis of persulfidated AtATG4a. Purified recombinant AtATG4a was treated in the absence (−) or in the presence of 50 mM DTT (+) for 30 min at 4°C, dialyzed, and subjected to the tag-switch labeling as described in the Methods. Then, the proteins were subjected to immunoblot analysis using anti-biotin antibodies. Sypro Ruby fluorescent staining is shown as the protein loading control.

(B) Analysis of AtATG4a using mass spectrometry. LC-MS/MS analysis of a tryptic peptide of AtATG4a containing Cys170. The table inside the spectrum contains the predicted ion types for the modified peptide, and the ions detected in the spectrum are highlighted in red.

(C) AtATG4a protein sequence identified with 97% coverage. The peptide containing persulfidated Cys170 is highlighted in yellow, and all the Cys residues are red.