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1
Content available remote Isoprenoid biosynthesis via 1-deoxy-D-xylulose 5-phosphate/2-C- methyl-D-erythritol 4-phosphate (DOXP/MEP) pathway.
100%
Wanke M. , Skorupinska-Tudek K. , Swiezewska E.
Acta Biochimica Polonica
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2001
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tom 48
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nr 3
663-672
EN
Higher plants, several algae, bacteria, some strains of Streptomyces and possibly malaria parasite Plasmodium falciparum contain the novel, plastidic DOXP/MEP pathway for isoprenoid biosynthesis. This pathway, alternative with respect to the classical mevalonate pathway, starts with condensation of pyruvate and glyceraldehyde-3-phosphate which yields 1-deoxy-D-xylulose 5-phosphate (DOXP); the latter product can be converted to isopentenyl diphosphate (IPP) and eventually to isoprenoids or thiamine and pyridoxal. Subsequent reactions of this pathway involve transformation of DOXP to 2-C-methyl-D-erythritol 4-phosphate (MEP) which after condensation with CTP forms 4-diphosphocytidyl-2-C-methyl-D-erythritol (CDP-ME). Then CDP-ME is phosphorylated to 4-diphosphocytidyl-2-C-methyl-D-erythritol 2-phosphate (CDP-ME2P) and to 2-C-methyl-D-erythritol-2,4-cyclodiphosphate (ME-2,4cPP) which is the last known intermediate of the DOXP/MEP pathway. Formation of IPP and dimethylallyl diphosphate (DMAPP) from ME-2,4cPP still requires clarification. This novel pathway appears to be involved in biosynthesis of carotenoids, phytol (side chain of chlorophylls), isoprene, mono-, di-, tetraterpenes and plastoquinone whereas the mevalonate pathway is responsible for formation of sterols, sesquiterpenes and triterpenes. Several isoprenoids were found to be of mixed origin suggesting that some exchange and/or cooperation exists between these two pathways of different biosynthetic origin. Contradictory results described below could indicate that these two pathways are operating under different physiological conditions of the cell and are dependent on the developmental state of plastids.
2
Content available remote Induction of the synthesis of an additional family of long-chain dolichols in the yeast Saccharomyces cerevisiae. Effect of starvation and ageing.
100%
Szkopinska A. , Swiezewska E. , Rytka J.
Acta Biochimica Polonica
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2002
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tom 49
|
nr 3
781-787
EN
The yeast Saccharomyces cerevisiae strain W303 synthesizes in the early logarithmic phase of growth dolichols of 14-18 isoprene residues. The analysis of the polyisoprenoids present in the stationary phase revealed an additional family which proved to be also dolichols but of 19-24 isoprene residues, constituting 39% of the total dolichols. The transfer of early logarithmic phase cells to a starvation medium lacking glucose or nitrogen resulted in the synthesis of the longer chain dolichols. The additional family of dolichols represented 13.8% and 10.3% of total dolichols in the glucose and nitrogen deficient media, respectively. The level of dolichols in yeast cells increased with the age of the cultures. Since both families of dolichols are present in stationary phase cells we postulate that the longer chain dolichols may be responsible for the physico-chemical changes in cellular membranes allowing yeast cells to adapt to nutrient deficient conditions to maintain long-term viability.
3
Content available remote Plastoquinone: possible involvement in plant disease resistance.
100%
Maciejewska U. , Polkowska-Kowalczyk L. , Swiezewska E. , Szkopinska A.
Acta Biochimica Polonica
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2002
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tom 49
|
nr 3
775-780
EN
The plant Solanum nigrum treated with the pathogen Phytophthora infestans-derived elicitor responded by elevated reactive oxygen species (ROS) production, lipid peroxidation and lipoxygenase (EC 1.13.11.12) activity in comparison with control plants indicating that oxidative stress took place. We demonstrate that these events are accompanied by a significant increase in plastoquinone (PQ) level. It is postulated that PQ may be associated with mechanisms maintaining a tightly controlled balance between the accumulation of ROS and antioxidant activity that determines the full expression of effective defence.
4
Content available remote Search for polyprenols in leaves of evergreen and deciduous Ericaceae plants.
88%
Ranjan R. , Marczewski A. , Chojnacki T. , Hertel J. , Swiezewska E.
Acta Biochimica Polonica
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2001
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tom 48
|
nr 2
579-584
EN
Various species and cultivars of Ericaceae family were checked for the presence of long-chain polyprenols in their leaves. In the genus Rhododendron no polyprenols were found in the ever-green species, while they were present in the deciduous type. The polyprenols were of chain-length of 14-20 isoprene residues and they occurred in the form of acetic acid esters. The polyprenol accumulation is discussed with respect to senescence of leaves.
5
Content available remote Prenyl sulfates as alkylating reagents for mercapto amino acids
75%
Maltsev S. , Sizova O. , Utkina N. , Shibaev V. , Chojnacki T. , Jankowski W. , Swiezewska E.
Acta Biochimica Polonica
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2008
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tom 55
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nr 4
807-813
EN
A new methodology for prenylation of thiol compounds has been developed. The approach is based on the use of prenyl sulfates as new reagents for S-prenylation of benzenethiol and cysteamine in aqueous systems. The C10-prenols geraniol and nerol that differ in the configuration (E or Z, correspondingly) of the α-isoprene unit were efficiently O-sulfated in the presence of a pyridine-SO3' complex. The obtained geranyl and neryl sulfates were tested as alkylating agents. These compounds were chosen to reveal the influence of the α-isoprene unit configuration on their alkylation (prenylation) ability. S-Geranyl cysteine was prepared to demonstrate the applicability of this method for prenylation of peptides containing mercapto amino acids.
6
Content available remote Functional relationships between the Saccharomyces cerevisiae cis-prenyltransferases required for dolichol biosynthesis.
75%
Grabińska K. , Sosińska G. , Orłowski J. , Swiezewska E. , Berges T. , Karst F. , Palamarczyk G.
Acta Biochimica Polonica
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2005
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tom 52
|
nr 1
221-232
EN
In the yeast Saccharomyces cerevisiae the RER2 and SRT1 genes encode Rer2 and Srt1 proteins with cis-prenyltransferase (cis-PT-ase) activity. Both cis-PT-ases utilize farnesyl diphosphate (FPP) as a starter for polyprenyl diphosphate (dolichol backbone) formation. The products of the Rer2 and Srt1 proteins consist of 14-17 and 18-23 isoprene units, respectively. In this work we demonstrate that deletion or overexpression of SRT1 up-regulates the activity of Rer2p and dolichol content. However, upon overexpression of SRT1, preferential synthesis of longer-chain dolichols and a decrease in the amount of the shorter species are observed. Furthermore, overexpression of the ERG20 gene (encoding farnesyl diphosphate synthase, Erg20p) induces transcription of SRT1 mRNA and increases the levels of mRNA for RER2 and DPM1 (dolichyl phosphate mannose synthase, Dpm1p). Subsequently the enzymatic activity of Rer2p and dolichol content are also increased. However, the amount of Dpm1p or its enzymatic activity remain unchanged.
7
Content available remote Dolichols of the fern Matteucia struthiopteris.
63%
Wojtas M. , Bieńkowski T. , Zelman-Femiak M. , Tateyama S. , Sagami H. , Chojnacki T. , Danikiewicz W. , Swiezewska E.
Acta Biochimica Polonica
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2005
|
tom 52
|
nr 1
255-259
EN
Dolichols isolated from leaves of the fern Matteucia struthiopteris were present as a mixture of prenologues composed of 14 up to 20 isoprene units with Dol-16 dominating. They comprised approximately 0.004% of the fresh weight of fresh plant tissue and were accompanied by traces of polyprenols (Pren-14 up to Pren-17, Pren-16 dominating). Their structure was confirmed by electropray ionization mass spectrometry (ESI-MS). This is the first time that dolichols have been reported as dominating polyisoprenoid alcohols in plant photosynthetic tissue.
8
Content available remote Light conditions alter accumulation of long chain polyprenols in leaves of trees and shrubs throughout the vegetation season.
63%
Bajda A. , Chojnacki T. , Hertel J. , Swiezewska E. , Wójcik J. , Kaczkowska A. , Marczewski A. , Bojarczuk T. , Karolewski P. , Oleksyn J.
Acta Biochimica Polonica
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2005
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tom 52
|
nr 1
233-241
EN
In many plants belonging to angiosperms and gymnosperms the accumulation in leaves of long chain polyprenols and polyprenyl esters during growth in natural habitats depends on the light intensity. The amount of polyprenols in leaves is also positively correlated with the thickness of the leaf blade (SLA, specific leaf area). The polyprenol content of leaves shows seasonal changes with a maximum in autumn and a minimum in early summer with the difference between poorly and well illuminated plants persisting throughout the vegetation season.
9
Content available remote In vitro plant tissue cultures accumulate polyisoprenoid alcohols
51%
Skorupinska-Tudek K. , Pytelewska A. , Zelman-Femiak M. , Mikoszewski J. , Olszowska O. , Gajdzis-Kuls D. , Urbanska N. , Syklowska-Baranek K. , Hertel J. , Chojnacki T. , Swiezewska E.
Acta Biochimica Polonica
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2007
|
tom 54
|
nr 4
847-852
EN
In vitro cultivated plant cells and tissues were found to synthesize polyisoprenoids. Taxus baccata suspension cell cultures accumulated polyisoprenoids of the same pattern as the parental tissue; methyl jasmonate or chitosan treatment almost doubled their content. All the root cultures studied accumulated dolichols as predominant polyisoprenoids. Roots of Ocimum sanctum grown in vitro accumulated approx. 2.5-fold higher amount of dolichols than the roots of soil-grown plants. Dolichols dominated over polyprenols in all Triticum sp. tissues studied.
10
Content available remote New cationic polyprenyl derivative proposed as a lipofecting agent
51%
Madeja Z. , Rak M. , Wybieralska E. , Różański I. , Masnyk M. , Chmielewski M. , Łysek R. , Chojnacki T. , Jankowski W. , Ciepichal E. , Swiezewska E. , Tekle M. , Dallner G.
Acta Biochimica Polonica
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2007
|
tom 54
|
nr 4
873-876
EN
Cationic linear poly-cis-isoprenoid prepared from natural plant polyprenol in a mixture with dioleyl phosphatidylethanolamine was found to be an effective lipofection agent for eukaryotic cells. The transfecting activity is related to the poly-cis structure of the polyprenyl chain.
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