Difference between revisions of "Pecina 2004 Am J Physiol Cell Physiol"
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|abstract=Mutations in the gene ''SURF1'' prevent synthesis of cytochrome-c oxidase (COX)-specific assembly protein and result in a fatal neurological disorder, Leigh syndrome. Because this severe COX deficiency presents with barely detectable changes of cellular respiratory rates under normoxic conditions, we analyzed the respiratory response to low oxygen in cultured fibroblasts harboring ''SURF1'' mutations with high-resolution respirometry. The oxygen kinetics was quantified by the partial pressure of oxygen (P<sub>O2</sub>) at half-maximal respiration rate (P<sub>50</sub>) in intact coupled cells and in digitonin-permeabilized uncoupled cells. In both cases, the P<sub>50</sub> in patients was elevated 2.1- and 3.3-fold, respectively, indicating decreased affinity of COX for oxygen. These results suggest that at physiologically low intracellular P<sub>O2</sub>, the depressed oxygen affinity may lead in vivo to limitations of respiration, resulting in impaired energy provision in Leigh syndrome patients. | |abstract=Mutations in the gene ''SURF1'' prevent synthesis of cytochrome-c oxidase (COX)-specific assembly protein and result in a fatal neurological disorder, Leigh syndrome. Because this severe COX deficiency presents with barely detectable changes of cellular respiratory rates under normoxic conditions, we analyzed the respiratory response to low oxygen in cultured fibroblasts harboring ''SURF1'' mutations with high-resolution respirometry. The oxygen kinetics was quantified by the partial pressure of oxygen (P<sub>O2</sub>) at half-maximal respiration rate (P<sub>50</sub>) in intact coupled cells and in digitonin-permeabilized uncoupled cells. In both cases, the P<sub>50</sub> in patients was elevated 2.1- and 3.3-fold, respectively, indicating decreased affinity of COX for oxygen. These results suggest that at physiologically low intracellular P<sub>O2</sub>, the depressed oxygen affinity may lead in vivo to limitations of respiration, resulting in impaired energy provision in Leigh syndrome patients. | ||
|keywords=Oxygen kinetics, Mitochondrial disease | |keywords=Oxygen kinetics, Mitochondrial disease | ||
|mipnetlab=AT_Innsbruck_Gnaiger E, CZ_Prague_Zeman J, CZ_Prague_Houstek J, AT Innsbruck MitoCom | |mipnetlab=AT_Innsbruck_Gnaiger E, CZ_Prague_Zeman J, CZ_Prague_Houstek J, AT Innsbruck MitoCom, CZ Prague Bioenergetics | ||
|discipline=Mitochondrial Physiology, Biomedicine | |discipline=Mitochondrial Physiology, Biomedicine | ||
}} | }} | ||
Revision as of 13:32, 7 December 2012
| Pecina P, Gnaiger E, Zeman J, Pronicka E, Houstek J (2004) Decreased affinity to oxygen of cytochrome c oxidase in Leigh syndrome caused by SURF1 mutations. Am J Physiol Cell Physiol 287: C1384-C1388. |
Pecina P, Gnaiger E, Zeman J, Pronicka E, Houstek J (2004) Am J Physiol Cell Physiol
Abstract: Mutations in the gene SURF1 prevent synthesis of cytochrome-c oxidase (COX)-specific assembly protein and result in a fatal neurological disorder, Leigh syndrome. Because this severe COX deficiency presents with barely detectable changes of cellular respiratory rates under normoxic conditions, we analyzed the respiratory response to low oxygen in cultured fibroblasts harboring SURF1 mutations with high-resolution respirometry. The oxygen kinetics was quantified by the partial pressure of oxygen (PO2) at half-maximal respiration rate (P50) in intact coupled cells and in digitonin-permeabilized uncoupled cells. In both cases, the P50 in patients was elevated 2.1- and 3.3-fold, respectively, indicating decreased affinity of COX for oxygen. These results suggest that at physiologically low intracellular PO2, the depressed oxygen affinity may lead in vivo to limitations of respiration, resulting in impaired energy provision in Leigh syndrome patients. • Keywords: Oxygen kinetics, Mitochondrial disease
• O2k-Network Lab: AT_Innsbruck_Gnaiger E, CZ_Prague_Zeman J, CZ_Prague_Houstek J, AT Innsbruck MitoCom, CZ Prague Bioenergetics
Labels:
Stress:Mitochondrial Disease; Degenerative Disease and Defect"Mitochondrial Disease; Degenerative Disease and Defect" is not in the list (Cell death, Cryopreservation, Ischemia-reperfusion, Permeability transition, Oxidative stress;RONS, Temperature, Hypoxia, Mitochondrial disease) of allowed values for the "Stress" property. Organism: Human Tissue;cell: Fibroblast Preparation: Intact Cell; Cultured; Primary"Intact Cell; Cultured; Primary" is not in the list (Intact organism, Intact organ, Permeabilized cells, Permeabilized tissue, Homogenate, Isolated mitochondria, SMP, Chloroplasts, Enzyme, Oxidase;biochemical oxidation, ...) of allowed values for the "Preparation" property., Oxidase; Biochemical Oxidation"Oxidase; Biochemical Oxidation" is not in the list (Intact organism, Intact organ, Permeabilized cells, Permeabilized tissue, Homogenate, Isolated mitochondria, SMP, Chloroplasts, Enzyme, Oxidase;biochemical oxidation, ...) of allowed values for the "Preparation" property., Enzyme
Coupling state: OXPHOS
HRR: Oxygraph-2k
