https://wiki.oroboros.at/index.php?title=Giulivi_2008_Biochem_J&feed=atom&action=historyGiulivi 2008 Biochem J - Revision history2024-03-29T10:42:41ZRevision history for this page on the wikiMediaWiki 1.36.1https://wiki.oroboros.at/index.php?title=Giulivi_2008_Biochem_J&diff=216257&oldid=prevGnaiger Erich at 16:53, 15 March 20212021-03-15T16:53:25Z<p></p>
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<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>* ''Addition of malonate, an inhibitor of Complex II, caused a 90% inhibition of pyruvate oxidation, demonstrating that the tricarboxylic acid cycle is required for pyruvate oxidation. .. Some isolated mitochondria oxidize pyruvate without added primers by carboxylating pyruvate to malate or oxaloacetate. Two enzymes have been described that can catalyse this carboxylation: malic enzyme [17] and PC (pyruvate carboxylase) [18]. .. Supplementation of mitochondria with malate yielded no significant increase in the rate of oxygen uptake in State 3 (Table 1) and, surprisingly, inhibited the response rate by 40%. These results suggested that, as observed in mammalian mitochondria, the transport of pyruvate and malate through the monocarboxylate–proton transporter and malate–citrate transporter respectively was also occurring in ASE mitochondria. However, the oxidation of malate to oxaloacetate proceeds through the enzymatic action of malate dehydrogenase in mammalian mitochondria, and because the <del style="font-weight: bold; text-decoration: none;">Keq </del>of this enzyme favours the formation of malate, oxaloacetate must be immediately removed by citrate synthase, a reaction that proceeds in the presence of acetyl-CoA formed from pyruvate via pyruvate dehydrogenase. The inhibition of malate oxidation by pyruvate addition in ASE mitochondria suggested a feedback inhibition of pyruvate <del style="font-weight: bold; text-decoration: none;">onmalic </del>enzyme, indicating that alternative carboxylation reactions to pyruvate oxidation were functional (e.g. via PC) and were similar to housefly sarcosomes. To confirm the involvement of malic enzyme, the effect of tartronic acid, an inhibitor of this enzyme, was tested on malate only or on malate- and pyruvate-supplemented mitochondria. Addition of tartronic acid resulted in 92% and 90% inhibition of State 3 oxygen uptake respectively. This result indicated that exogenously added malate efficiently provides oxaloacetate (through malate dehydrogenase), whereas pyruvate is provided via the anaplerotic reaction catalysed by malic enzyme.''</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>* ''Addition of malonate, an inhibitor of Complex II, caused a 90 % inhibition of pyruvate oxidation, demonstrating that the tricarboxylic acid cycle is required for pyruvate oxidation. .. Some isolated mitochondria oxidize pyruvate without added primers by carboxylating pyruvate to malate or oxaloacetate. Two enzymes have been described that can catalyse this carboxylation: malic enzyme [17] and PC (pyruvate carboxylase) [18]. .. Supplementation of mitochondria with malate yielded no significant increase in the rate of oxygen uptake in State 3 (Table 1) and, surprisingly, inhibited the response rate by 40 %. These results suggested that, as observed in mammalian mitochondria, the transport of pyruvate and malate through the monocarboxylate–proton transporter and malate–citrate transporter respectively was also occurring in ASE mitochondria. However, the oxidation of malate to oxaloacetate proceeds through the enzymatic action of malate dehydrogenase in mammalian mitochondria, and because the <ins style="font-weight: bold; text-decoration: none;">''K''<sub>eq</sub> </ins>of this enzyme favours the formation of malate, oxaloacetate must be immediately removed by citrate synthase, a reaction that proceeds in the presence of acetyl-CoA formed from pyruvate via pyruvate dehydrogenase. The inhibition of malate oxidation by pyruvate addition in ASE mitochondria suggested a feedback inhibition of pyruvate <ins style="font-weight: bold; text-decoration: none;">on malic </ins>enzyme, indicating that alternative carboxylation reactions to pyruvate oxidation were functional (e.g. via PC) and were similar to housefly sarcosomes. To confirm the involvement of malic enzyme, the effect of tartronic acid, an inhibitor of this enzyme, was tested on malate only or on malate- and pyruvate-supplemented mitochondria. Addition of tartronic acid resulted in 92 % and 90 % inhibition of State 3 oxygen uptake respectively. This result indicated that exogenously added malate efficiently provides oxaloacetate (through malate dehydrogenase), whereas pyruvate is provided via the anaplerotic reaction catalysed by malic enzyme.''</div></td></tr>
</table>Gnaiger Erichhttps://wiki.oroboros.at/index.php?title=Giulivi_2008_Biochem_J&diff=124868&oldid=prevBeno Marija at 07:55, 9 November 20162016-11-09T07:55:16Z<p></p>
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</table>Beno Marijahttps://wiki.oroboros.at/index.php?title=Giulivi_2008_Biochem_J&diff=123465&oldid=prevBeno Marija at 14:43, 7 November 20162016-11-07T14:43:40Z<p></p>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* ''Addition of malonate, an inhibitor of Complex II, caused a 90% inhibition of pyruvate oxidation, demonstrating that the tricarboxylic acid cycle is required for pyruvate oxidation. .. Some isolated mitochondria oxidize pyruvate without added primers by carboxylating pyruvate to malate or oxaloacetate. Two enzymes have been described that can catalyse this carboxylation: malic enzyme [17] and PC (pyruvate carboxylase) [18]. .. Supplementation of mitochondria with malate yielded no significant increase in the rate of oxygen uptake in State 3 (Table 1) and, surprisingly, inhibited the response rate by 40%. These results suggested that, as observed in mammalian mitochondria, the transport of pyruvate and malate through the monocarboxylate–proton transporter and malate–citrate transporter respectively was also occurring in ASE mitochondria. However, the oxidation of malate to oxaloacetate proceeds through the enzymatic action of malate dehydrogenase in mammalian mitochondria, and because the Keq of this enzyme favours the formation of malate, oxaloacetate must be immediately removed by citrate synthase, a reaction that proceeds in the presence of acetyl-CoA formed from pyruvate via pyruvate dehydrogenase. The inhibition of malate oxidation by pyruvate addition in ASE mitochondria suggested a feedback inhibition of pyruvate onmalic enzyme, indicating that alternative carboxylation reactions to pyruvate oxidation were functional (e.g. via PC) and were similar to housefly sarcosomes. To confirm the involvement of malic enzyme, the effect of tartronic acid, an inhibitor of this enzyme, was tested on malate only or on malate- and pyruvate-supplemented mitochondria. Addition of tartronic acid resulted in 92% and 90% inhibition of State 3 oxygen uptake respectively. This result indicated that exogenously added malate efficiently provides oxaloacetate (through malate dehydrogenase), whereas pyruvate is provided via the anaplerotic reaction catalysed by malic enzyme.''</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* ''Addition of malonate, an inhibitor of Complex II, caused a 90% inhibition of pyruvate oxidation, demonstrating that the tricarboxylic acid cycle is required for pyruvate oxidation. .. Some isolated mitochondria oxidize pyruvate without added primers by carboxylating pyruvate to malate or oxaloacetate. Two enzymes have been described that can catalyse this carboxylation: malic enzyme [17] and PC (pyruvate carboxylase) [18]. .. Supplementation of mitochondria with malate yielded no significant increase in the rate of oxygen uptake in State 3 (Table 1) and, surprisingly, inhibited the response rate by 40%. These results suggested that, as observed in mammalian mitochondria, the transport of pyruvate and malate through the monocarboxylate–proton transporter and malate–citrate transporter respectively was also occurring in ASE mitochondria. However, the oxidation of malate to oxaloacetate proceeds through the enzymatic action of malate dehydrogenase in mammalian mitochondria, and because the Keq of this enzyme favours the formation of malate, oxaloacetate must be immediately removed by citrate synthase, a reaction that proceeds in the presence of acetyl-CoA formed from pyruvate via pyruvate dehydrogenase. The inhibition of malate oxidation by pyruvate addition in ASE mitochondria suggested a feedback inhibition of pyruvate onmalic enzyme, indicating that alternative carboxylation reactions to pyruvate oxidation were functional (e.g. via PC) and were similar to housefly sarcosomes. To confirm the involvement of malic enzyme, the effect of tartronic acid, an inhibitor of this enzyme, was tested on malate only or on malate- and pyruvate-supplemented mitochondria. Addition of tartronic acid resulted in 92% and 90% inhibition of State 3 oxygen uptake respectively. This result indicated that exogenously added malate efficiently provides oxaloacetate (through malate dehydrogenase), whereas pyruvate is provided via the anaplerotic reaction catalysed by malic enzyme.''</div></td></tr>
</table>Beno Marijahttps://wiki.oroboros.at/index.php?title=Giulivi_2008_Biochem_J&diff=100868&oldid=prevKandolf Georg at 15:04, 7 December 20152015-12-07T15:04:43Z<p></p>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* ''Addition of malonate, an inhibitor of Complex II, caused a 90% inhibition of pyruvate oxidation, demonstrating that the tricarboxylic acid cycle is required for pyruvate oxidation. .. Some isolated mitochondria oxidize pyruvate without added primers by carboxylating pyruvate to malate or oxaloacetate. Two enzymes have been described that can catalyse this carboxylation: malic enzyme [17] and PC (pyruvate carboxylase) [18]. .. Supplementation of mitochondria with malate yielded no significant increase in the rate of oxygen uptake in State 3 (Table 1) and, surprisingly, inhibited the response rate by 40%. These results suggested that, as observed in mammalian mitochondria, the transport of pyruvate and malate through the monocarboxylate–proton transporter and malate–citrate transporter respectively was also occurring in ASE mitochondria. However, the oxidation of malate to oxaloacetate proceeds through the enzymatic action of malate dehydrogenase in mammalian mitochondria, and because the Keq of this enzyme favours the formation of malate, oxaloacetate must be immediately removed by citrate synthase, a reaction that proceeds in the presence of acetyl-CoA formed from pyruvate via pyruvate dehydrogenase. The inhibition of malate oxidation by pyruvate addition in ASE mitochondria suggested a feedback inhibition of pyruvate onmalic enzyme, indicating that alternative carboxylation reactions to pyruvate oxidation were functional (e.g. via PC) and were similar to housefly sarcosomes. To confirm the involvement of malic enzyme, the effect of tartronic acid, an inhibitor of this enzyme, was tested on malate only or on malate- and pyruvate-supplemented mitochondria. Addition of tartronic acid resulted in 92% and 90% inhibition of State 3 oxygen uptake respectively. This result indicated that exogenously added malate efficiently provides oxaloacetate (through malate dehydrogenase), whereas pyruvate is provided via the anaplerotic reaction catalysed by malic enzyme.''</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* ''Addition of malonate, an inhibitor of Complex II, caused a 90% inhibition of pyruvate oxidation, demonstrating that the tricarboxylic acid cycle is required for pyruvate oxidation. .. Some isolated mitochondria oxidize pyruvate without added primers by carboxylating pyruvate to malate or oxaloacetate. Two enzymes have been described that can catalyse this carboxylation: malic enzyme [17] and PC (pyruvate carboxylase) [18]. .. Supplementation of mitochondria with malate yielded no significant increase in the rate of oxygen uptake in State 3 (Table 1) and, surprisingly, inhibited the response rate by 40%. These results suggested that, as observed in mammalian mitochondria, the transport of pyruvate and malate through the monocarboxylate–proton transporter and malate–citrate transporter respectively was also occurring in ASE mitochondria. However, the oxidation of malate to oxaloacetate proceeds through the enzymatic action of malate dehydrogenase in mammalian mitochondria, and because the Keq of this enzyme favours the formation of malate, oxaloacetate must be immediately removed by citrate synthase, a reaction that proceeds in the presence of acetyl-CoA formed from pyruvate via pyruvate dehydrogenase. The inhibition of malate oxidation by pyruvate addition in ASE mitochondria suggested a feedback inhibition of pyruvate onmalic enzyme, indicating that alternative carboxylation reactions to pyruvate oxidation were functional (e.g. via PC) and were similar to housefly sarcosomes. To confirm the involvement of malic enzyme, the effect of tartronic acid, an inhibitor of this enzyme, was tested on malate only or on malate- and pyruvate-supplemented mitochondria. Addition of tartronic acid resulted in 92% and 90% inhibition of State 3 oxygen uptake respectively. This result indicated that exogenously added malate efficiently provides oxaloacetate (through malate dehydrogenase), whereas pyruvate is provided via the anaplerotic reaction catalysed by malic enzyme.''</div></td></tr>
</table>Kandolf Georghttps://wiki.oroboros.at/index.php?title=Giulivi_2008_Biochem_J&diff=80693&oldid=prevBader Helga at 12:53, 13 February 20152015-02-13T12:53:05Z<p></p>
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<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>|tissues=Skeletal muscle</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>|tissues=Skeletal muscle</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>|preparations=Isolated <del style="font-weight: bold; text-decoration: none;">Mitochondria</del></div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>|preparations=Isolated <ins style="font-weight: bold; text-decoration: none;">mitochondria</ins></div></td></tr>
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<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>|substratestates=CI, CII, ETF, <del style="font-weight: bold; text-decoration: none;">GpDH</del>, CIV, Other combinations, ROX</div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>|substratestates=CI, CII, ETF, <ins style="font-weight: bold; text-decoration: none;">CGpDH</ins>, CIV, Other combinations, ROX</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>|additional=Malic enzyme</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>|additional=Malic enzyme</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>}}</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>}}</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* ''Addition of malonate, an inhibitor of Complex II, caused a 90% inhibition of pyruvate oxidation, demonstrating that the tricarboxylic acid cycle is required for pyruvate oxidation. .. Some isolated mitochondria oxidize pyruvate without added primers by carboxylating pyruvate to malate or oxaloacetate. Two enzymes have been described that can catalyse this carboxylation: malic enzyme [17] and PC (pyruvate carboxylase) [18]. .. Supplementation of mitochondria with malate yielded no significant increase in the rate of oxygen uptake in State 3 (Table 1) and, surprisingly, inhibited the response rate by 40%. These results suggested that, as observed in mammalian mitochondria, the transport of pyruvate and malate through the monocarboxylate–proton transporter and malate–citrate transporter respectively was also occurring in ASE mitochondria. However, the oxidation of malate to oxaloacetate proceeds through the enzymatic action of malate dehydrogenase in mammalian mitochondria, and because the Keq of this enzyme favours the formation of malate, oxaloacetate must be immediately removed by citrate synthase, a reaction that proceeds in the presence of acetyl-CoA formed from pyruvate via pyruvate dehydrogenase. The inhibition of malate oxidation by pyruvate addition in ASE mitochondria suggested a feedback inhibition of pyruvate onmalic enzyme, indicating that alternative carboxylation reactions to pyruvate oxidation were functional (e.g. via PC) and were similar to housefly sarcosomes. To confirm the involvement of malic enzyme, the effect of tartronic acid, an inhibitor of this enzyme, was tested on malate only or on malate- and pyruvate-supplemented mitochondria. Addition of tartronic acid resulted in 92% and 90% inhibition of State 3 oxygen uptake respectively. This result indicated that exogenously added malate efficiently provides oxaloacetate (through malate dehydrogenase), whereas pyruvate is provided via the anaplerotic reaction catalysed by malic enzyme.''</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* ''Addition of malonate, an inhibitor of Complex II, caused a 90% inhibition of pyruvate oxidation, demonstrating that the tricarboxylic acid cycle is required for pyruvate oxidation. .. Some isolated mitochondria oxidize pyruvate without added primers by carboxylating pyruvate to malate or oxaloacetate. Two enzymes have been described that can catalyse this carboxylation: malic enzyme [17] and PC (pyruvate carboxylase) [18]. .. Supplementation of mitochondria with malate yielded no significant increase in the rate of oxygen uptake in State 3 (Table 1) and, surprisingly, inhibited the response rate by 40%. These results suggested that, as observed in mammalian mitochondria, the transport of pyruvate and malate through the monocarboxylate–proton transporter and malate–citrate transporter respectively was also occurring in ASE mitochondria. However, the oxidation of malate to oxaloacetate proceeds through the enzymatic action of malate dehydrogenase in mammalian mitochondria, and because the Keq of this enzyme favours the formation of malate, oxaloacetate must be immediately removed by citrate synthase, a reaction that proceeds in the presence of acetyl-CoA formed from pyruvate via pyruvate dehydrogenase. The inhibition of malate oxidation by pyruvate addition in ASE mitochondria suggested a feedback inhibition of pyruvate onmalic enzyme, indicating that alternative carboxylation reactions to pyruvate oxidation were functional (e.g. via PC) and were similar to housefly sarcosomes. To confirm the involvement of malic enzyme, the effect of tartronic acid, an inhibitor of this enzyme, was tested on malate only or on malate- and pyruvate-supplemented mitochondria. Addition of tartronic acid resulted in 92% and 90% inhibition of State 3 oxygen uptake respectively. This result indicated that exogenously added malate efficiently provides oxaloacetate (through malate dehydrogenase), whereas pyruvate is provided via the anaplerotic reaction catalysed by malic enzyme.''</div></td></tr>
</table>Bader Helgahttps://wiki.oroboros.at/index.php?title=Giulivi_2008_Biochem_J&diff=76554&oldid=prevGnaiger Erich at 07:49, 14 December 20142014-12-14T07:49:30Z<p></p>
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<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>|title=Giulivi C, Ross-Inta C, Horton AA, Luckhart S (2008) Metabolic pathways in ''Anopheles stephensi'' mitochondria. Biochem J 415: 309-16. </div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>|title=Giulivi C, Ross-Inta C, Horton AA, Luckhart S (2008) Metabolic pathways in ''Anopheles stephensi'' mitochondria. Biochem J 415:309-16.</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>|info=[http://www.ncbi.nlm.nih.gov/pubmed/18588503 PMID: 18588503 Open Access]</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>|info=[http://www.ncbi.nlm.nih.gov/pubmed/18588503 PMID: 18588503 Open Access]</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>|authors=Giulivi C, Ross-Inta C, Horton AA, Luckhart S</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>|authors=Giulivi C, Ross-Inta C, Horton AA, Luckhart S</div></td></tr>
</table>Gnaiger Erichhttps://wiki.oroboros.at/index.php?title=Giulivi_2008_Biochem_J&diff=66162&oldid=prevGnaiger Erich at 15:07, 1 August 20142014-08-01T15:07:23Z<p></p>
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<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>|title=Giulivi C, Ross-Inta C, Horton AA, Luckhart S (2008) Metabolic pathways in Anopheles stephensi mitochondria. Biochem J 415: 309-16. </div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>|title=Giulivi C, Ross-Inta C, Horton AA, Luckhart S (2008) Metabolic pathways in <ins style="font-weight: bold; text-decoration: none;">''</ins>Anopheles stephensi<ins style="font-weight: bold; text-decoration: none;">'' </ins>mitochondria. Biochem J 415: 309-16. </div></td></tr>
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</table>Gnaiger Erichhttps://wiki.oroboros.at/index.php?title=Giulivi_2008_Biochem_J&diff=66161&oldid=prevGnaiger Erich: Created page with "{{Publication |title=Giulivi C, Ross-Inta C, Horton AA, Luckhart S (2008) Metabolic pathways in Anopheles stephensi mitochondria. Biochem J 415: 309-16. |info=[http://www.ncbi.n..."2014-08-01T15:05:15Z<p>Created page with "{{Publication |title=Giulivi C, Ross-Inta C, Horton AA, Luckhart S (2008) Metabolic pathways in Anopheles stephensi mitochondria. Biochem J 415: 309-16. |info=[http://www.ncbi.n..."</p>
<p><b>New page</b></p><div>{{Publication<br />
|title=Giulivi C, Ross-Inta C, Horton AA, Luckhart S (2008) Metabolic pathways in Anopheles stephensi mitochondria. Biochem J 415: 309-16. <br />
|info=[http://www.ncbi.nlm.nih.gov/pubmed/18588503 PMID: 18588503 Open Access]<br />
|authors=Giulivi C, Ross-Inta C, Horton AA, Luckhart S<br />
|year=2008<br />
|journal=Biochem J<br />
|abstract=No studies have been performed on the mitochondria of malaria vector mosquitoes. This information would be valuable in understanding mosquito aging and detoxification of insecticides, two parameters that have a significant impact on malaria parasite transmission in endemic regions. In the present study, we report the analyses of respiration and oxidative phosphorylation in mitochondria of cultured cells [ASE (Anopheles stephensi Mos. 43) cell line] from A. stephensi, a major vector of malaria in India, South-East Asia and parts of the Middle East. ASE cell mitochondria share many features in common with mammalian muscle mitochondria, despite the fact that these cells are of larval origin. However, two major differences with mammalian mitochondria were apparent. One, the glycerol-phosphate shuttle plays as major a role in NADH oxidation in ASE cell mitochondria as it does in insect muscle mitochondria. In contrast, mammalian white muscle mitochondria depend primarily on lactate dehydrogenase, whereas red muscle mitochondria depend on the malate-oxaloacetate shuttle. Two, ASE mitochondria were able to oxidize proline at a rate comparable with that of alpha-glycerophosphate. However, the proline pathway appeared to differ from the currently accepted pathway, in that oxoglutarate could be catabolized completely by the tricarboxylic acid cycle or via transamination, depending on the ATP need.<br />
}}<br />
{{Labeling<br />
|area=Respiration, Comparative MiP;environmental MiP<br />
|organism=Human, Rat<br />
|taxonomic group=Birds, Hexapods<br />
|tissues=Skeletal muscle<br />
|preparations=Isolated Mitochondria<br />
|couplingstates=LEAK, OXPHOS<br />
|substratestates=CI, CII, ETF, GpDH, CIV, Other combinations, ROX<br />
|additional=Malic enzyme<br />
}}<br />
* ''Addition of malonate, an inhibitor of Complex II, caused a 90% inhibition of pyruvate oxidation, demonstrating that the tricarboxylic acid cycle is required for pyruvate oxidation. .. Some isolated mitochondria oxidize pyruvate without added primers by carboxylating pyruvate to malate or oxaloacetate. Two enzymes have been described that can catalyse this carboxylation: malic enzyme [17] and PC (pyruvate carboxylase) [18]. .. Supplementation of mitochondria with malate yielded no significant increase in the rate of oxygen uptake in State 3 (Table 1) and, surprisingly, inhibited the response rate by 40%. These results suggested that, as observed in mammalian mitochondria, the transport of pyruvate and malate through the monocarboxylate–proton transporter and malate–citrate transporter respectively was also occurring in ASE mitochondria. However, the oxidation of malate to oxaloacetate proceeds through the enzymatic action of malate dehydrogenase in mammalian mitochondria, and because the Keq of this enzyme favours the formation of malate, oxaloacetate must be immediately removed by citrate synthase, a reaction that proceeds in the presence of acetyl-CoA formed from pyruvate via pyruvate dehydrogenase. The inhibition of malate oxidation by pyruvate addition in ASE mitochondria suggested a feedback inhibition of pyruvate onmalic enzyme, indicating that alternative carboxylation reactions to pyruvate oxidation were functional (e.g. via PC) and were similar to housefly sarcosomes. To confirm the involvement of malic enzyme, the effect of tartronic acid, an inhibitor of this enzyme, was tested on malate only or on malate- and pyruvate-supplemented mitochondria. Addition of tartronic acid resulted in 92% and 90% inhibition of State 3 oxygen uptake respectively. This result indicated that exogenously added malate efficiently provides oxaloacetate (through malate dehydrogenase), whereas pyruvate is provided via the anaplerotic reaction catalysed by malic enzyme.''</div>Gnaiger Erich