Titelangaben
Szederkényi, Judit ; Komor, Ewald ; Schobert, Christian:
Cloning of the cdna for glutaredoxin, an abundant sieve-tube exudate protein from ricinus communis l. and characterisation of the glutathione-dependent thiol-reduction system in sieve tubes.
In: Planta.
Bd. 202
(1997)
Heft 3
.
- S. 349-356.
ISSN 0032-0935
DOI: https://doi.org/10.1007/s004250050137
Abstract
Sieve-tube exudate protein (STEP) from Ricinus communis L. seedlings consists of a characteristic set of more than 100 different polypeptides, against which a complex antiserum was raised. This antiserum cross-reacted with dominant protein species (molecular weights 10-30 kDa) present in the sieve-tube exudate and, to a lesser extent, with proteins in tissue extracts of Ricinus and a wide range of other plant species. For further elucidation of the nature of individual STEPs in the sieve tubes the anti-STEP serum was used to screen a cDNA expression library constructed from Ricinus cotyledon mRNA. Two clones that differed in the 3' untranslated region encoded a protein of 11 kDa which showed striking homology to bacterial and eucaryotic glutaredoxin sequences. Glutaredoxin activity was confirmed for the recombinant protein after overexpression in Escherichia coli and characterised in detail in sieve-tube exudate. Michaelis Menten constants (K-m) for reduced glutathione and cysteine were 2 mM and 50 mu M, respectively. Besides L-cysteine, dehydroascorbate and protein disulphides were also reduced by the activity present in the sieve-tube exudate. Glutathione, which is the obligate donor of reduced thiols for glutaredoxin, was present in sieve-tube sap in millimolar concentrations (up to 3 mM) with a ratio of total to oxidised glutathione of 3:1. It is suggested that glutaredoxin and glutathione in sieve tubes prevent oxidative damage and may be involved in redox regulation of sieve-tube proteins.
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Publikationsform: | Artikel in einer Zeitschrift |
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Begutachteter Beitrag: | Ja |
Zusätzliche Informationen: | BAYCEER22504 |
Institutionen der Universität: | Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Biologie > Lehrstuhl Pflanzenphysiologie Forschungseinrichtungen > Forschungszentren > Bayreuther Zentrum für Ökologie und Umweltforschung - BayCEER Fakultäten Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Biologie Forschungseinrichtungen Forschungseinrichtungen > Forschungszentren |
Titel an der UBT entstanden: | Ja |
Themengebiete aus DDC: | 500 Naturwissenschaften und Mathematik |
Eingestellt am: | 30 Okt 2015 07:19 |
Letzte Änderung: | 30 Okt 2015 07:19 |
URI: | https://eref.uni-bayreuth.de/id/eprint/20991 |