Fig. 1.

Experimental overview. Mice (total of 4), strain CB6F1 (BALB/cBy × C57BL/6), were killed by cervical dislocation. Hearts were excised and processed to isolate mitochondria. Isolated mitochondria were treated with 10 μM biotin SS-31 (bSS-31, blue rectangle with yellow triangle) for 1 h. Oxygen consumption rates and H₂O₂ production were monitored to evaluate the functional impact of bSS-31 (Fig. 3 B–D). Mitochondria were cross-linked with the PIR cross-linker DP-NHP (gray rectangle with orange stars). Protein was extracted using 8 M urea and digested with trypsin. Enrichment for peptides containing bSS-31 was performed with immobilized monomeric avidin. Peptide samples were analyzed by LC-MS to identify the interactome network for bSS-31 and structural analysis was performed using cross-link distance restraint guided molecular docking.