at Google ScholarTitle data
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.
Vol. 202
(1997)
Issue 3
.
- pp. 349-356.
ISSN 0032-0935
DOI: https://doi.org/10.1007/s004250050137
Abstract in another language
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.
Further data
| Item Type: | Article in a journal |
|---|---|
| Refereed: | Yes |
| Additional notes: | BAYCEER22504 |
| Institutions of the University: | Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Biology > Chair Plant Physiology Research Institutions > Research Centres > Bayreuth Center of Ecology and Environmental Research- BayCEER Faculties Faculties > Faculty of Biology, Chemistry and Earth Sciences Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Biology Research Institutions Research Institutions > Research Centres |
| Result of work at the UBT: | Yes |
| DDC Subjects: | 500 Science |
| Date Deposited: | 30 Oct 2015 07:19 |
| Last Modified: | 30 Oct 2015 07:19 |
| URI: | https://eref.uni-bayreuth.de/id/eprint/20991 |