Proteomic analysis of mitochondria from the heart of Bos taurus . III. Identification of proteins of the inner mitochondrial membrane

Proteins of the inner mitochondrial membrane packed into submitochondrial particles (SMP) have been investigated. SMPs were treated with trypsin, and the peptides were separated from the so-called “shaved vesicles”. The “shaved vesicles” were disrupted, and the proteins and peptides obtained were subjected to cleavage by cyanogen bromide and trypsin. The two groups of tryptic peptides obtained were analyzed separately using proteomic methods, namely, chromatographic fractionation of peptides, mass spectrometric identification and a search in amino acid sequence databases. The possibility of non-specific fragmentation was also taken into account when identification of proteins of the inner mitochondrial membrane was performed. Reliable identification of 298 proteins allowed for a more precise estimation of their localization in the cell and analysis of their function.