STUDIES ON MITOCHONDRIAL STRUCTURAL PROTEIN .3. PHYSICAL CHARACTERIZATION OF STRUCTURAL PROTEINS OF BEEF HEART AND BEEF LIVER MITOCHONDRIA

The several species of purified structural proteins isolated from beef heart and beef liver mitochondria have been shown to have similar solubility properties, similar composition of amino acids, similar peptide maps after tryptic digestion, and similar if not identical molecular weights, and to contain either aspartate or alanine as N-terminal amino acid. These similarities and identities provide the experimental foundation for considering the various species of structural protein as members of a general class of noncatalytic proteins, all of which represent the predominant protein species (some 50%, of the total protein) in the detachable sectors of membrane repeating units. © 1968.