المؤلفون: Roberto Pizzuto, Daniela Valenti, Gianluca Paventi, Lidia de Bari, Anna Atlante, Salvatore Passarella

المصدر: Biochimica et biophysica acta. Bioenergetics 1708 (2005): 13–22. doi:10.1016/j.bbabio.2005.03.005
info:cnr-pdr/source/autori:Atlante A, de Bari L, Valenti D, Pizzuto R, Paventi G, Passarella S./titolo:Transport and metabolism of D-lactate in Jerusalem artichoke mitochondria./doi:10.1016%2Fj.bbabio.2005.03.005/rivista:Biochimica et biophysica acta. Bioenergetics/anno:2005/pagina_da:13/pagina_a:22/intervallo_pagine:13–22/volume:1708

مصطلحات موضوعية: Biophysics, Antimycin A, Jerusalem artichoke mitochondria, Plant Roots, Biochemistry, d-lactate, chemistry.chemical_compound, Cytosol, Oxygen Consumption, Lactate dehydrogenase, Lactic Acid, Methylglyoxal pathway, Lactate Dehydrogenases, Mitochondrial transport, Symporters, Methylglyoxal, Biological Transport, Stereoisomerism, Metabolism, Cell Biology, Glyoxalase II, Pyruvaldehyde, Mitochondria, d-lactate dehydrogenase, chemistry, D-lactate dehydrogenase, Helianthus, D-lactate, D-lactate dehydrogenase, Glyoxalase II, Jerusalem artichoke mitochondria, Methylglyoxal pathway, Mitochondrial transport, Thiolester Hydrolases, Jerusalem artichoke

الوصف: We report here initial studies on d -lactate metabolism in Jerusalem artichoke. It was found that: 1) d -lactate can be synthesized by Jerusalem artichoke by virtue of the presence of glyoxalase II, the activity of which was measured photometrically in both isolated Jerusalem artichoke mitochondria and cytosolic fraction after the addition of S- d -lactoyl-glutathione. 2) Externally added d -lactate caused oxygen consumption by mitochondria, mitochondrial membrane potential increase and proton release, in processes that were insensitive to rotenone, but inhibited by both antimycin A and cyanide. 3) d -lactate was metabolized inside mitochondria by a flavoprotein, a putative d -lactate dehydrogenase, the activity of which could be measured photometrically in mitochondria treated with Triton X-100. 4) Jerusalem artichoke mitochondria can take up externally added d -lactate by means of a d -lactate/H+ symporter investigated by measuring the rate of reduction of endogenous flavins. The action of the d -lactate translocator and of the mitochondrial d -lactate dehydrogenase could be responsible for the subsequent metabolism of d -lactate formed from methylglyoxal in the cytosol of Jerusalem artichoke.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::92d5e528be65029cb2766e2f072d0cb9Test

المؤلفون: Daniela Valenti, Salvatore Passarella, Maria Luigia Pallotta, Michelina Iacovino

المصدر: Biochimica et biophysica acta. Bioenergetics 1608 (2004): 104–113. doi:10.1016/j.bbabio.2003.10.008
info:cnr-pdr/source/autori:Pallotta ML, Valenti D, Iacovino M, Passarella S./titolo:Two separate pathways for d-lactate oxidation by Saccharomyces cerevisiae mitochondria which differ in energy production and carrier involvement./doi:10.1016%2Fj.bbabio.2003.10.008/rivista:Biochimica et biophysica acta. Bioenergetics/anno:2004/pagina_da:104/pagina_a:113/intervallo_pagine:104–113/volume:1608

مصطلحات موضوعية: Pyruvate dehydrogenase kinase, Saccharomyces cerevisiae Proteins, Antiporter, Biophysics, Antimycin A, Transport, Saccharomyces cerevisiae, Mitochondrion, Biochemistry, Membrane Potentials, Cytochrome b2, chemistry.chemical_compound, Adenosine Triphosphate, Pyruvic Acid, Lactic Acid, Lactate Dehydrogenases, ATP synthase, biology, L-Lactate Dehydrogenase, Cell Biology, mitochondria, chemistry, Gluconeogenesis, D-Lactate, Dehydrogenase, Mitochondrial matrix, Cinnamates, d-Lactate, biology.protein, L-Lactate Dehydrogenase (Cytochrome), Carrier, Energy Metabolism, Oxidation-Reduction

الوصف: In this work we looked at whether and how mitochondria isolated from Saccharomyces cerevisiae (SCM) oxidize d-lactate. We found that: (1). externally added d-lactate causes oxygen uptake by SCM with P/O ratio equal to 1.5; in the presence of antimycin A (AA), P/O ratio was 1.8, differently in the presence of the non-penetrant alpha-cyanocinnamate (alpha-CCN-) no P/O ratio could be measured. Consistently, mitochondrial electrical membrane potential (deltapsi) generation was found, due to externally added d-lactate in the presence of antimycin A, but not of alpha-CCN-. (2). SCM oxidize d-lactate in two different manners: (i). via inner membrane d-lactate dehydrogenase which leads to d-lactate oxidation without driving deltapsi generation and ATP synthesis and (ii). via the matrix d-lactate dehydrogenase, which drives deltapsi generation and ATP synthesis by using taken up d-lactate. (3). Pyruvate newly synthesised in the mitochondrial matrix is exported via the novel d-lactate/pyruvate antiporter. d-Lactate/pyruvate antiport proved to regulate the rate of pyruvate efflux in vitro. (4). The existence of the d-lactate/H+ symporter is also proposed as shown by mitochondrial swelling. The d-lactate carriers and d-lactate dehydrogenases could account for the removal of the toxic methylglyoxal from cytosol, as well as for the d-lactate-dependent gluconeogenesis.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::dae1bf6f8d3812db4cd871e984f58e83Test