Chapter 11 Supercomplex organization of the yeast respiratory chain complexes and the ADP/ATP carrier proteins.
The enzymes involved in mitochondrial oxidative phosphorylation (OXPHOS) are coassembled into higher ordered supercomplexes within the mitochondrial inner membrane. The cytochrome bc(1)-cytochrome c oxidase (COX) supercomplex is formed by the coassociation of the two electron transport chain complexes, the cytochrome bc(1) (cytochrome c reductase) and the COX complex. Recent evidence indicates that a diversity in the populations of the cytochrome bc(1)-COX supercomplexes exists within the mitochondria, because different subpopulations of this supercomplex have been shown to further interact with distinct partner complexes (e.g., the TIM23 machinery and also the Shy1/Cox14 proteins). By use of native gel electrophoresis and affinity purification approaches, the abundant ADP/ATP carrier protein (AAC) isoform in the yeast Saccharomyces cerevisiae, the Aac2 isoform, has recently been found to also exist in physical association with the cytochrome bc(1)-COX supercomplex and its associated TIM23 machinery. The AAC proteins play a central role in cellular metabolism, because they facilitate the exchange of ADP and ATP across the mitochondrial inner membrane. The method used to analyze the cytochrome bc(1)-COX-AAC supercomplex and to affinity purify the Aac2 isoform and its associating proteins from S. cerevisiae mitochondria will be outlined in this chapter.
Stuart
Rosemary A
RA
Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin, USA.
D002846:Chromatography, Affinity; D003902:Detergents / Q000737:chemistry; D004072:Digitonin / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D009097:Multienzyme Complexes / Q000378:metabolism*; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*
C037688:ADP-ATP carrier receptor; D003902:Detergents; D009097:Multienzyme Complexes; D018160:Receptors, Cytoplasmic and Nuclear; D004072:Digitonin