{"title":"On the activation of two chlorplastic phosphatases by fructose bisphosphate, sedoheptulose bisphosphate and magnesium","authors":"Brigitte Gontero, J.C. Meunier, Jacques Ricard","doi":"10.1016/0304-4211(84)90168-8","DOIUrl":null,"url":null,"abstract":"<div><p>Fructose bisphosphatase and the ‘alternate’ phosphatase, when purified to homogeneity from spinach chloroplasts, are only slightly activated upon pre-incubation with Mg<sup>2+</sup>, fructose bisphosphate or sedoheptulose bisphosphate, as well as by a mixture of the divalent cation and either of these sugar phosphates. This activating effect is much smaller than that produced by thioredoxin <em>f</em><sub><em>B</em></sub> and becomes null if thioredoxin <em>f</em><sub><em>B</em></sub> is present. It is therefore very unlikely that fructose bisphosphate, sedoheptulose bisphosphate or Mg<sup>2+</sup> may play a significant role in the light activation of the two phosphatases.</p><p>Magnesium slowly deactivates the active fructose bisphosphatase but slightly enhances the activity of the already activated ‘alternate’ phosphatase. Owing to their slowness, these processes are likely not to play any significant biological role.</p></div>","PeriodicalId":20221,"journal":{"name":"Plant Science Letters","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"1984-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0304-4211(84)90168-8","citationCount":"13","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Plant Science Letters","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/0304421184901688","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 13
Abstract
Fructose bisphosphatase and the ‘alternate’ phosphatase, when purified to homogeneity from spinach chloroplasts, are only slightly activated upon pre-incubation with Mg2+, fructose bisphosphate or sedoheptulose bisphosphate, as well as by a mixture of the divalent cation and either of these sugar phosphates. This activating effect is much smaller than that produced by thioredoxin fB and becomes null if thioredoxin fB is present. It is therefore very unlikely that fructose bisphosphate, sedoheptulose bisphosphate or Mg2+ may play a significant role in the light activation of the two phosphatases.
Magnesium slowly deactivates the active fructose bisphosphatase but slightly enhances the activity of the already activated ‘alternate’ phosphatase. Owing to their slowness, these processes are likely not to play any significant biological role.