Figure 4.

(IP)IAA-labeled mitochondrial peptides are enriched via sequential avidin enrichments

IPIAA-labeled mitochondrial proteins that were previously enriched on streptavidin resin are then trypsin digested into peptides off the resin (step 1). Digested IPIAA-labeled peptides are then conjugated to biotin-azide via CuAAC- mediated ‘click’ chemistry (step 2). Biotinylated cysteine peptides are then enriched on neutravidin resin (step 3), and eluted cysteine peptides are used for LC-MS/MS analysis in the following steps.