In mitochondria, four respiratory-chain complexes drive oxidative phosphorylation by sustaining a proton-motive force across the inner membrane that is used to synthesize ATP. The question of how the densely packed proteins of the inner membrane are organized to optimize structure and function has returned to prominence with the characterization of respiratory-chain supercomplexes. Supercomplex...

Several D P N H dehydrogenases have been purified from heart mitochondria or heart-muscle preparationsl-L STRAUB'S enzym& has been shown by MASSEY 8 to be a form of lipoamide dehydrogenase (EC 1.6.4.3), while the relationship of the remaining preparations to the respiratory chain and to each other is obscure. The flavin extractable by acid t reatment has been reported to be FMN in some casesl, ...

Background: Mitochondrial disorders can present as kidney disease in children and be difficult to diagnose. Measurement of mitochondrial function in kidney tissue may help diagnosis. This study was to assess the feasibility of obtaining renal samples and analysing them for respiratory chain enzyme activity. Methods: The subjects were children undergoing a routine diagnostic renal biopsy, in who...

In [ l ] low concentrations of Tinopal AN, (1,l-bis(3,N-5-dimethylbenzoxazol-2-y1)methine p-toluene sulphonate), which is present in the optical brightener Uvitex AN (Ciba-Geigy Ltd) [2], inhibited the aerobic respiration of Paracoccus denitrificans. Using inverted membrane vesicles of P. denitrifcans [I], this inhibition was shown to occur in the NADH dehydrogenase (EC 1.66.99.3) region of the...

BACKGROUND Sirtuins are NAD+ dependent deacetylases, which regulate mitochondrial energy metabolism as well as cellular response to stress. The NAD/NADH-system plays a crucial role in oxidative phosphorylation linking sirtuins and the mitochondrial respiratory chain. Furthermore, sirtuins are able to directly deacetylate and activate different complexes of the respiratory chain. This prompted u...

Mitochondrial dysfunction is heavily implicated in the ageing process. Increasing age in mammals correlates with accumulation of somatic mitochondrial DNA (mtDNA) mutations and decline in respiratory chain function. The age-associated respiratory chain deficiency is typically unevenly distributed and affects only a subset of cells in various human tissues, such as heart, skeletal muscle, coloni...

OBJECTIVE To explore the relationship between α-synuclein pathology and mitochondrial respiratory chain protein levels within single substantia nigra neurons. DESIGN We examined α-synuclein and mitochondrial protein expression in substantia nigra neurons of 8 patients with dementia with Lewy bodies, 5 patients with Parkinson disease, and 8 control subjects. Protein expression was determined u...

A decrease in oxidative phosphorylation (OXPHOS) is characteristic of many cancer types and, in particular, of clear cell renal carcinoma (CCRC) deficient in von Hippel-Lindau (vhl) gene. In the absence of functional pVHL, hypoxia-inducible factor (HIF) 1-alpha and HIF2-alpha subunits are stabilized, which induces the transcription of many genes including those involved in glycolysis and reacti...

OBJECTIVE To study the impact of adipocyte differentiation on nucleoside reverse transcriptase inhibitor (NRTI)-mediated mitochondrial DNA (mtDNA) depletion and to correlate mtDNA depletion with the activity of the respiratory chain complexes. METHODS We studied adipocyte phenotype, viability, differentiation (CCAAT/enhancer-binding protein [C/EBP]-alpha and peroxisome proliferator-activated ...