| dc.creator | Büchert, Agustín M. | |
| dc.creator | Civello, Pedro Marcos | |
| dc.creator | Martínez, Gustavo Adolfo | |
| dc.date | 2011-03-01 | |
| dc.date | 2022-03-30T13:34:27Z | |
| dc.date.accessioned | 2023-07-15T04:38:51Z | |
| dc.date.available | 2023-07-15T04:38:51Z | |
| dc.identifier | http://sedici.unlp.edu.ar/handle/10915/133524 | |
| dc.identifier | issn:0006-3134 | |
| dc.identifier | issn:1573-8264 | |
| dc.identifier.uri | https://repositorioslatinoamericanos.uchile.cl/handle/2250/7470352 | |
| dc.description | The removal of Mg<sup>2+</sup> is an important step in the chlorophyll degradation pathway and extracts from senescent and presenescent <i>Arabidopsis thaliana</i> leaves were analyzed for Mg-dechelatase activity, using chlorophyllin, an artificial derivative of the natural substrate, chlorophyllide. The optimum temperature and pH for this reaction were determined to be at approximately 50 °C and 7.2, respectively. Mg-dechelatase activity was enhanced by addition of EDTA and inhibited by MgCl<sub>2</sub>, HgCl<sub>2</sub> and reduced glutathione, indicating phenomenons such as retroinhibition by reaction products and dependence on the redox state of the mixture. Size exclusion chromatography was performed on <i>Arabidopsis</i> leaf extracts, and Mg-dechelatase activity was found in the fraction corresponding to molecular mass of about 42 kDa, which indicates that the Mg-dechelating compound in <i>Arabidopsis</i> is considerably larger than in other systems. During dark-induced senescence, the activity increased over time until reaching a maximum at day 4, and then decreased. The addition of plant growth regulators indicated that the accumulation of Mg-dechelatase was activated by ethylene and delayed by 6-benzylaminopurine. | |
| dc.description | Instituto de Fisiología Vegetal | |
| dc.format | application/pdf | |
| dc.format | 75-82 | |
| dc.language | es | |
| dc.rights | http://creativecommons.org/licenses/by-nc-sa/4.0/ | |
| dc.rights | Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) | |
| dc.subject | Biología | |
| dc.subject | chlorophyll degradation | |
| dc.subject | chlorophyllin | |
| dc.subject | pheophorbide | |
| dc.title | Characterization of Mg-dechelating substance in senescent and pre-senescent Arabidopsis thaliana leaves | |
| dc.type | Articulo | |
| dc.type | Articulo | |
