The branched mitochondrial respiratory chain from Debaryomyces hansenii: components and supramolecular organization.
The branched respiratory chain in mitochondria from the halotolerant yeast Debaryomyces hansenii contains the classical complexes I, II, III and IV plus a cyanide-insensitive, AMP-activated, alternative-oxidase (AOX). Two additional alternative oxidoreductases were found in this organism: an alternative NADH dehydrogenase (NDH2e) and a mitochondrial isoform of glycerol-phosphate dehydrogenase (MitGPDH). These monomeric enzymes lack proton pump activity. They are located on the outer face of the inner mitochondrial membrane. NDH2e oxidizes exogenous NADH in a rotenone-insensitive, flavone-sensitive, process. AOX seems to be constitutive; nonetheless, most electrons are transferred to the cytochromic pathway. Respiratory supercomplexes containing complexes I, III and IV in different stoichiometries were detected. Dimeric complex V was also detected. In-gel activity of NADH dehydrogenase, mass spectrometry, and cytochrome c oxidase and ATPase activities led to determine the composition of the putative supercomplexes. Molecular weights were estimated by comparison with those from the yeast Y. lipolytica and they were IV2, I-IV, III2-IV4, V2, I-III2, I-III2-IV, I-III2-IV2, I-III2-IV3 and I-III2-IV4. Binding of the alternative enzymes to supercomplexes was not detected. This is the first report on the structure and organization of the mitochondrial respiratory chain from D. hansenii.
Dept. of Molecular Genetics, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico.
Alfredo
A
Cabrera-Orefice
Natalia
N
Chiquete-Félix
Juan
J
Espinasa-Jaramillo
Mónica
M
Rosas-Lemus
Sergio
S
Guerrero-Castillo
Antonio
A
Peña
Salvador
S
Uribe-Carvajal
D000595:Amino Acid Sequence; D019069:Cell Respiration / Q000502:physiology; D055165:Debaryomyces / Q000201:enzymology; D004579:Electron Transport; D042967:Electron Transport Complex I / Q000737:chemistry* / Q000378:metabolism; D005993:Glycerolphosphate Dehydrogenase / Q000737:chemistry* / Q000502:physiology; D008928:Mitochondria / Q000201:enzymology / Q000378:metabolism; D051336:Mitochondrial Membranes / Q000737:chemistry / Q000201:enzymology; D024101:Mitochondrial Proteins / Q000737:chemistry / Q000378:metabolism; D009245:NADH Dehydrogenase / Q000737:chemistry* / Q000502:physiology; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000737:chemistry* / Q000378:metabolism; D010940:Plant Proteins / Q000737:chemistry / Q000378:metabolism; D000099188:Alternative Oxidase
D042967:Electron Transport Complex I; D005993:Glycerolphosphate Dehydrogenase; D024101:Mitochondrial Proteins; D009245:NADH Dehydrogenase; D010088:Oxidoreductases; D010940:Plant Proteins; D000099188:Alternative Oxidase
(Mit)GPDH; 2D; ADP; AMP; AOX; Alternative NADH dehydrogenase; Alternative oxidase; BN; COX; CRR; Debaryomyces hansenii; Dig; Glycerol-phosphate dehydrogenase; IMM; LC-MS; LM; MUC; MW; NADH dehydrogenase activity; NDH; NDH2e; PAGE; PG; ROS; Respiratory chain; SDS; Supercomplexes; adenosine diphosphate; adenosine monophosphate; alternative external NADH dehydrogenase; alternative oxidase; blue-native; cyanide-resistant respiration; cytochrome c oxidase; digitonin; glycerol-phosphate dehydrogenase (mitochondrial isoform); inner mitochondrial membrane; laurylmaltoside; liquid chromatography mass spectrometry; mitochondrial unspecific channel; molecular weight; polyacrylamide-gel electrophoresis; propyl-gallate; reactive oxygen species; second dimension; sodium dodecyl sulfate