[12] Native electrophoresis for isolation of mitochondrial oxidative phosphorylation protein complexes

This chapter focuses on the native electrophoresis for the isolation of mitochondrial oxidative phosphorylation protein complexes and the preparative use of Blue-Native electrophoresis and subsequent sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), exemplified by the isolation of oxidative phosphorylation (OX-PHOS) complexes and their protein subunits from bovine heart mitochondria. Electrophoretic techniques for the isolation and quantification of OX-PHOS complexes from human tissues, applied to the studies of OX-PHOS defects in human diseases, are described in the chapter. The OX-PHOS technique allows the quantitative recovery of proteins from SDS gels because any protein fixation prior to electro elution is avoided. Blue-SDS-PAGE differs from normal SDS-PAGE by the reduction of the SDS concentration in the cathode buffer. This chapter concludes with the discussion on the analysis of molecular masses and the oligomeric states of native proteins and complexes.