Difference between revisions of "Guzun 2009 Biochim Biophys Acta"
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|couplingstates=OXPHOS | |couplingstates=OXPHOS | ||
|kinetics=ADP; Pi, Reduced Substrate; Cytochrome c | |kinetics=ADP; Pi, Reduced Substrate; Cytochrome c | ||
|topics=Ion | |topics=Ion homeostasis, Redox state, Substrate; Glucose; TCA Cycle | ||
|discipline=Mitochondrial Physiology, Biomedicine | |discipline=Mitochondrial Physiology, Biomedicine | ||
}} | }} |
Revision as of 16:16, 6 August 2013
Guzun R, Timohhina N, Tepp K, Monge C, Kaambre T, Sikk P, Kuznetsov AV, Pison C, Saks V (2009) Regulation of respiration controlled by mitochondrial creatine kinase in permeabilized cardiac cells in situ. Importance of system level properties. Biochim Biophys Acta 1787: 1089-1105. |
Guzun R, Timohhina N, Tepp K, Monge C, Kaambre T, Sikk P, Kuznetsov AV, Pison C, Saks V (2009) Biochim Biophys Acta
Abstract: The main focus of this investigation is steady state kinetics of regulation of mitochondrial respiration in permeabilized cardiomyocytes in situ. Complete kinetic analysis of the regulation of respiration by mitochondrial creatine kinase was performed in the presence of pyruvate kinase and phosphoenolpyruvate to simulate interaction of mitochondria with glycolytic enzymes. Such a system analysis revealed striking differences in kinetic behaviour of the MtCK-activated mitochondrial respiration in situ and in vitro. Apparent dissociation constants of MgATP from its binary and ternary complexes with MtCK, Kia and Ka (1.94 ± 0.86 mM and 2.04 ± 0.14 mM, correspondingly) were increased by several orders of magnitude in situ in comparison with same constants in vitro (0.44 ± 0.08 mM and 0.016 ± 0.01 mM, respectively). Apparent dissociation constants of creatine, Kib and Kb (2.12 ± 0.21 mM 2.17 ± 0.40 Mm, correspondingly) were significantly decreased in situ in comparison with in vitro mitochondria (28 ± 7 mM and 5 ± 1.2 mM, respectively). Dissociation constant for phosphocreatine was not changed. These data may indicate selective restriction of metabolites diffusion at the level of mitochondrial outer membrane. It is concluded that mechanisms of the regulation of respiration and energy fluxes in vivo are system level properties which depend on intracellular interactions of mitochondria with cytoskeleton, intracellular MgATPases and cytoplasmic glycolytic system. • Keywords: Respiration, Cardiomyocyte, Mitochondria, Creatine kinase, Creatine
• O2k-Network Lab: EE_Tallinn_Saks VA, FR_Grenoble_Saks VA
Labels:
Organism: Rat
Tissue;cell: Heart
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.
Regulation: Ion homeostasis"Ion homeostasis" is not in the list (Aerobic glycolysis, ADP, ATP, ATP production, AMP, Calcium, Coupling efficiency;uncoupling, Cyt c, Flux control, Inhibitor, ...) of allowed values for the "Respiration and regulation" property., Redox state, Substrate; Glucose; TCA Cycle"Substrate; Glucose; TCA Cycle" is not in the list (Aerobic glycolysis, ADP, ATP, ATP production, AMP, Calcium, Coupling efficiency;uncoupling, Cyt c, Flux control, Inhibitor, ...) of allowed values for the "Respiration and regulation" property. Coupling state: OXPHOS
HRR: Oxygraph-2k