Characterization of Mg-dechelating substance in senescent and pre-senescent Arabidopsis thaliana leaves

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 s...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Büchert, Agustín M., Civello, Pedro Marcos, Martínez, Gustavo Adolfo
Formato: Articulo
Lenguaje:Español
Publicado: 2011
Materias:
Biología
chlorophyll degradation
chlorophyllin
pheophorbide
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/133524
Aporte de:
SEDICI (UNLP) de Universidad Nacional de La Plata
id I19-R120-10915-133524
record_format dspace
institution Universidad Nacional de La Plata
institution_str I-19
repository_str R-120
collection SEDICI (UNLP)
language Español
topic Biología
chlorophyll degradation
chlorophyllin
pheophorbide
spellingShingle Biología
chlorophyll degradation
chlorophyllin
pheophorbide
Büchert, Agustín M.
Civello, Pedro Marcos
Martínez, Gustavo Adolfo
Characterization of Mg-dechelating substance in senescent and pre-senescent Arabidopsis thaliana leaves
topic_facet Biología
chlorophyll degradation
chlorophyllin
pheophorbide
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.
format Articulo
Articulo
author Büchert, Agustín M.
Civello, Pedro Marcos
Martínez, Gustavo Adolfo
author_facet Büchert, Agustín M.
Civello, Pedro Marcos
Martínez, Gustavo Adolfo
author_sort Büchert, Agustín M.
title Characterization of Mg-dechelating substance in senescent and pre-senescent Arabidopsis thaliana leaves
title_short Characterization of Mg-dechelating substance in senescent and pre-senescent Arabidopsis thaliana leaves
title_full Characterization of Mg-dechelating substance in senescent and pre-senescent Arabidopsis thaliana leaves
title_fullStr Characterization of Mg-dechelating substance in senescent and pre-senescent Arabidopsis thaliana leaves
title_full_unstemmed Characterization of Mg-dechelating substance in senescent and pre-senescent Arabidopsis thaliana leaves
title_sort characterization of mg-dechelating substance in senescent and pre-senescent arabidopsis thaliana leaves
publishDate 2011
url http://sedici.unlp.edu.ar/handle/10915/133524
work_keys_str_mv AT buchertagustinm characterizationofmgdechelatingsubstanceinsenescentandpresenescentarabidopsisthalianaleaves
AT civellopedromarcos characterizationofmgdechelatingsubstanceinsenescentandpresenescentarabidopsisthalianaleaves
AT martinezgustavoadolfo characterizationofmgdechelatingsubstanceinsenescentandpresenescentarabidopsisthalianaleaves
bdutipo_str Repositorios
_version_ 1764820454862749697

Ejemplares similares