Differentiation between leaks and slips in oxidative phosphorylation

Groen, Brenda H.; Berden, J.A.; Dam, K. Van

doi:10.1016/0005-2728(90)90132-n

Cited by 24 publications

(7 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…An increase in the yield of mitochondrial ATP synthesis may involve an increase in coupling H + /O stoichiometry at the level of the respiratory complexes (slip reactions) or a decrease in proton leak reactions or both (Groen et al, 1990;Brand, 2005). In the present study, the improvement of mitochondrial efficiency in pectoralis muscles was clearly associated with a reduction of mitochondrial oxidative phosphorylation proteins, including cytochrome c oxidase subunit.…”

Section: Discussionmentioning

confidence: 44%

“…Interestingly, it has been previously reported that a decrease in cytochrome c oxidase content and/or activity increased the overall ATP synthesis yield of mitochondria, resulting in a significant shift of the linear relationship between oxygen consumption and ATP synthesis to the left, with a significant decrease in basal non-phosphorylating respiration (Piquet et al, 2000;Nogueira et al, 2002;Clerc et al, 2007), similar to what was found in the present study. These data thus suggest that the fastinginduced increase in the yield of mitochondrial ATP synthesis might involve slip reactions (changes in the coupling H + /O stoichiometry) at the level of the respiratory complexes (Groen et al, 1990).…”

Section: Discussionmentioning

confidence: 81%

See 1 more Smart Citation

Skeletal muscle heterogeneity in fasting-induced mitochondrial oxidative phosphorylation flexibility in cold-acclimated ducklings

Monternier

Fongy

Hervant

et al. 2015

Journal of Experimental Biology

View full text Add to dashboard Cite

Starvation is particularly challenging for endotherms that remain active in cold environments or during winter. The aim of this study was to determine whether fasting-induced mitochondrial coupling flexibility depends upon the phenotype of skeletal muscles. The rates of oxidative phosphorylation and mitochondrial efficiency were measured in pectoralis (glycolytic) and gastrocnemius (oxidative) muscles from cold-acclimated ducklings (Cairina moschata). Pyruvate and palmitoyl-L-carnitine were used in the presence of malate as respiratory substrates. Plasma metabolites, skeletal muscle concentrations of triglycerides, glycogen and total protein and mitochondrial levels of oxidative phosphorylation complexes were also quantified. Results from ad libitum fed ducklings were compared with those from ducklings that were fasted for 4 days. During the 4 days of nutritional treatment, birds remained in the cold, at 4°C. The 4 days of starvation preferentially affected the pectoralis muscles, inducing an up-regulation of mitochondrial efficiency, which was associated with a reduction of both total muscle and mitochondrial oxidative phosphorylation protein, and with an increase of intramuscular lipid concentration. By contrast, fasting decreased the activity of oxidative phosphorylation but did not alter the coupling efficiency and protein expression of mitochondria isolated from the gastrocnemius muscles. Hence, the adjustment of mitochondrial efficiency to fasting depends upon the muscle phenotype of cold-acclimated birds. Furthermore, these results suggest that the reduced cost of mitochondrial ATP production in pectoralis muscles may trigger lipid storage within this tissue and help to sustain an important metabolic homeostatic function of skeletal muscles, which is to maintain levels of amino acids in the circulation during the fast.

show abstract

Section: Discussionmentioning

confidence: 44%

Section: Discussionmentioning

confidence: 81%

Skeletal muscle heterogeneity in fasting-induced mitochondrial oxidative phosphorylation flexibility in cold-acclimated ducklings

Monternier

Fongy

Hervant

et al. 2015

Journal of Experimental Biology

View full text Add to dashboard Cite

show abstract

“…It is generally accepted that slip reactions involved in energy conversion are only evident for COX (Murphy and Brand, ; Papa et al., ). In addition, a causal relation seems to exist between the amount or activity of COX and the overall ATP synthesis yield (Groen et al., ; Nogueira et al., ). Accordingly, if the higher oxidative phosphorylation efficiency of HGR frogs resulted from slip reactions, then a decrease in COX activity should be expected (Nogueira et al., ; Clerc et al., ).…”

Section: Discussionmentioning

confidence: 99%

David and Goliath: A Mitochondrial Coupling Problem?

et al. 2012

View full text Add to dashboard Cite

An organism's size, known to affect biological structures and processes from cellular metabolism to population dynamics, depends upon the duration and rate of growth. However, it is still poorly understood how mitochondrial function affects the energetic basis of growth, especially in ectotherms, which represent a huge majority of animal biodiversity. Here, we present an intraspecies comparison of neighboring populations of frogs (Rana temporaria) that have large differences in body mass even at the same age. By investigating liver mitochondrial bioenergetics, we find that frogs with high growth rates and large body sizes exhibit higher ATP synthesis rates and more efficient oxidative phosphorylation compared to the smaller frogs with low growth rates. This higher energy transduction efficiency is not associated with significant increased oxidative capacity or membrane potential values, but instead may rely on a higher mitochondrial phosphorylation system activity in combination with a lower inner membrane proton leakage. Overall, the present study introduces the mitochondrial energy transduction system as an important mechanism for balancing physiological and ecological trade-offs associated with body size. Whether phenotype differences in mitochondrial function result from local ecological constraints or reflect a natural genetic variability within wild populations of common frogs remains an open question. However, our findings highlight the need for closer consideration of all aspects of mitochondrial metabolism for a better understanding of the physiological basis of the link between size, metabolism, and energy production in wild-dwelling organisms.

show abstract

“…A redox slip would occur if an electron would pass by a regular coupling site of an electron transport chain. This is observed in tetramethyl-pphenylendiamine treated mitochondria (Groen et al, 1990). A proton leak involves the passive back flow of protons through a leaky site of a membrane, which has been observed with photodamaged thylakoids (Ögren and Öquist, 1984;Terashima et al, 1991;Tjus and Andersson, 1993;Curwiel and Van Rensen, 1993).…”

Section: Introductionmentioning

confidence: 92%

“…The ATP content was measured as the increase in absorption at 340 nm after addition of hexokinase and glucose-6-phosphate dehydrogenase to the samples (Groen et al, 1990). The electron transport was calculated from the loss of absorption at 420 nm associated with the reduction of FeCy using an of 1.035 cm À2 mmol À1 .…”

Section: Photosynthetic Electron Transport and Photophosphorylationmentioning

confidence: 99%