{"title":"吲哚乙酸对线粒体活性的调节","authors":"Igor V. Sarkissian, Robert G. McDaniel","doi":"10.1016/0926-6593(66)90001-4","DOIUrl":null,"url":null,"abstract":"<div><p>Mitochondria of scutella of a maize inbred were allowed to respire in the presence of indoleacetic acid. Greatest enhancement of <span><math><mtext>Q</mtext><msub><mi></mi><mn><mtext>O</mtext><msub><mi></mi><mn>2</mn></msub></mn></msub><msup><mi></mi><mn><mtext>N</mtext></mn></msup></math></span>, P/N and P/O was observed with indoleacetic acid concentration around 1.07 · 10<sup>−10</sup> M. At concentrations above 1.07 · 10<sup>−8</sup> M, O<sub>2</sub> uptake was greatly inhibited while phosphorylation was inhibited to a lesser degree. It was shown that enhancement of mitochondrial activity is dependent on CoA; without added CoA, effects of indoleacetic acid were slight. The most effective concentration of CoA was shown to be 0.1 mg/2.8 ml reaction mixture. In the presence of 1.07 · 10<sup>−10</sup> M indoleacetic acid, rate of O<sub>2</sub> uptake measured at 3-min intervals was greatly increased. In addition, with indoleacetic acid in the reaction mixture, mitochondria showed an almost immediate enhancement of activity while the control reaction and the reaction with high concentration of indoleacetic acid (1.07 · 10<sup>−5</sup> M) exhibited a lag of 3–4 min. With regard to the relationship of CoA and indoleacetic acid-induced stimulation of rate of mitochondrial O<sub>2</sub> uptake, two points were observed: without added CoA, the rate of O<sub>2</sub> uptake is sharply reduced and there is a lag of 7 min before mitochondria show any O<sub>2</sub> uptake.</p><p>The results suggest that indoleacetic acid enhances mitochondrial activity by affecting the enzyme(s) of the oxidative phosphorylation pathway. It is suggested that indoleacetic acid accomplishes such enhancement by acting as an allosteric effector.</p></div>","PeriodicalId":100160,"journal":{"name":"Biochimica et Biophysica Acta (BBA) - Enzymology and Biological Oxidation","volume":"128 3","pages":"Pages 413-418"},"PeriodicalIF":0.0000,"publicationDate":"1966-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0926-6593(66)90001-4","citationCount":"9","resultStr":"{\"title\":\"Regulation of mitochondrial activity by indoleacetic acid\",\"authors\":\"Igor V. Sarkissian, Robert G. McDaniel\",\"doi\":\"10.1016/0926-6593(66)90001-4\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Mitochondria of scutella of a maize inbred were allowed to respire in the presence of indoleacetic acid. Greatest enhancement of <span><math><mtext>Q</mtext><msub><mi></mi><mn><mtext>O</mtext><msub><mi></mi><mn>2</mn></msub></mn></msub><msup><mi></mi><mn><mtext>N</mtext></mn></msup></math></span>, P/N and P/O was observed with indoleacetic acid concentration around 1.07 · 10<sup>−10</sup> M. At concentrations above 1.07 · 10<sup>−8</sup> M, O<sub>2</sub> uptake was greatly inhibited while phosphorylation was inhibited to a lesser degree. It was shown that enhancement of mitochondrial activity is dependent on CoA; without added CoA, effects of indoleacetic acid were slight. The most effective concentration of CoA was shown to be 0.1 mg/2.8 ml reaction mixture. In the presence of 1.07 · 10<sup>−10</sup> M indoleacetic acid, rate of O<sub>2</sub> uptake measured at 3-min intervals was greatly increased. In addition, with indoleacetic acid in the reaction mixture, mitochondria showed an almost immediate enhancement of activity while the control reaction and the reaction with high concentration of indoleacetic acid (1.07 · 10<sup>−5</sup> M) exhibited a lag of 3–4 min. With regard to the relationship of CoA and indoleacetic acid-induced stimulation of rate of mitochondrial O<sub>2</sub> uptake, two points were observed: without added CoA, the rate of O<sub>2</sub> uptake is sharply reduced and there is a lag of 7 min before mitochondria show any O<sub>2</sub> uptake.</p><p>The results suggest that indoleacetic acid enhances mitochondrial activity by affecting the enzyme(s) of the oxidative phosphorylation pathway. It is suggested that indoleacetic acid accomplishes such enhancement by acting as an allosteric effector.</p></div>\",\"PeriodicalId\":100160,\"journal\":{\"name\":\"Biochimica et Biophysica Acta (BBA) - Enzymology and Biological Oxidation\",\"volume\":\"128 3\",\"pages\":\"Pages 413-418\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"1966-12-14\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://sci-hub-pdf.com/10.1016/0926-6593(66)90001-4\",\"citationCount\":\"9\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Biochimica et Biophysica Acta (BBA) - Enzymology and Biological Oxidation\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/0926659366900014\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Biochimica et Biophysica Acta (BBA) - Enzymology and Biological Oxidation","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/0926659366900014","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Regulation of mitochondrial activity by indoleacetic acid
Mitochondria of scutella of a maize inbred were allowed to respire in the presence of indoleacetic acid. Greatest enhancement of , P/N and P/O was observed with indoleacetic acid concentration around 1.07 · 10−10 M. At concentrations above 1.07 · 10−8 M, O2 uptake was greatly inhibited while phosphorylation was inhibited to a lesser degree. It was shown that enhancement of mitochondrial activity is dependent on CoA; without added CoA, effects of indoleacetic acid were slight. The most effective concentration of CoA was shown to be 0.1 mg/2.8 ml reaction mixture. In the presence of 1.07 · 10−10 M indoleacetic acid, rate of O2 uptake measured at 3-min intervals was greatly increased. In addition, with indoleacetic acid in the reaction mixture, mitochondria showed an almost immediate enhancement of activity while the control reaction and the reaction with high concentration of indoleacetic acid (1.07 · 10−5 M) exhibited a lag of 3–4 min. With regard to the relationship of CoA and indoleacetic acid-induced stimulation of rate of mitochondrial O2 uptake, two points were observed: without added CoA, the rate of O2 uptake is sharply reduced and there is a lag of 7 min before mitochondria show any O2 uptake.
The results suggest that indoleacetic acid enhances mitochondrial activity by affecting the enzyme(s) of the oxidative phosphorylation pathway. It is suggested that indoleacetic acid accomplishes such enhancement by acting as an allosteric effector.