Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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Interaction between parental environment and genotype affects plant and seed performance in Arabidopsis
He, H. ; Souza Vidigal, D. De; Snoek, L.B. ; Schnabel, S.K. ; Nijveen, H. ; Hilhorst, H. ; Bentsink, L. - \ 2014
Journal of Experimental Botany 65 (2014)22. - ISSN 0022-0957 - p. 6603 - 6615.
sativa miller brassicaceae - abscisic-acid biosynthesis - maturation environment - drought tolerance - natural variation - key enzyme - dormancy - germination - thaliana - temperature
Seed performance after dispersal is highly dependent on parental environmental cues, especially during seed formation and maturation. Here we examine which environmental factors are the most dominant in this respect and whether their effects are dependent on the genotypes under investigation. We studied the influence of light intensity, photoperiod, temperature, nitrate, and phosphate during seed development on five plant attributes and thirteen seed attributes, using 12 Arabidopsis genotypes that have been reported to be affected in seed traits. As expected, the various environments during seed development resulted in changed plant and/or seed performances. Comparative analysis clearly indicated that, overall, temperature plays the most dominant role in both plant and seed performance, whereas light has a prominent impact on plant traits. In comparison to temperature and light, nitrate mildly affected some of the plant and seed traits while phosphate had even less influence on those traits. Moreover, clear genotype-by-environment interactions were identified. This was shown by the fact that individual genotypes responded differentially to the environmental conditions. Low temperature significantly increased seed dormancy and decreased seed longevity of NILDOG1 and cyp707a1-1, whereas low light intensity increased seed dormancy and decreased seed longevity of NILDOG3 and NILDOG6. This also indicates that different genetic and molecular pathways are involved in the plant and seed responses. By identifying environmental conditions that affect the dormancy vs longevity correlation in the same way as previously identified naturally occurring loci, we have identified selective forces that probably shaped evolution for these important seed traits.
Evaluation of tobacco (Nicotiana tabacum L. cv. Petit Havana SR1) hairy roots for the production of geraniol, the first committed step in terpenoid indole alkaloid pathway
Ritala, A. ; Dong, L. ; Imseng, N. ; Seppanen-Laakso, T. ; Vasilev, N. ; Krol, A.R. van der; Rischer, H. ; Maaheimo, H. ; Virkki, A. ; Brandli, J. ; Schillberg, S. ; Eibl, R. ; Bouwmeester, H.J. ; Oksman-Caldentey, K.M. - \ 2014
Journal of Biotechnology 176 (2014). - ISSN 0168-1656 - p. 20 - 28.
catharanthus-roseus - isoprenoid biosynthesis - plastidial pathways - essential oils - key enzyme - monoterpene - cultures - synthase - cells - bioreactors
The terpenoid indole alkaloids are one of the major classes of plant-derived natural products and are well known for their many applications in the pharmaceutical, fragrance and cosmetics industries. Hairy root cultures are useful for the production of plant secondary metabolites because of their genetic and biochemical stability and their rapid growth in hormone-free media. Tobacco (Nicotiana tabacum L. cv. Petit Havana SR1) hairy roots, which do not produce geraniol naturally, were engineered to express a plastidtargeted geraniol synthase gene originally isolated from Valeriana officinalis L. (VoGES). A SPME-GC–MS screening tool was developed for the rapid evaluation of production clones. The GC–MS analysis revealed that the free geraniol content in 20 hairy root clones expressing VoGES was an average of 13.7 g/g dry weight (DW) and a maximum of 31.3 g/g DW. More detailed metabolic analysis revealed that geraniol derivatives were present in six major glycoside forms, namely the hexose and/or pentose conjugates of geraniol and hydroxygeraniol, resulting in total geraniol levels of up to 204.3 g/g DW following deglycosylation. A benchtop-scale process was developed in a 20-L wave-mixed bioreactor eventually yielding hundreds of grams of biomass and milligram quantities of geraniol per cultivation bag.
NON-SMOKY GLYCOSYLTRANSFERASE1 Prevents the Release of Smoky Aroma from Tomato Fruit
Tikunov, Y.M. ; Molthoff, J.W. ; Vos, R.C.H. de; Beekwilder, M.J. ; Houwelingen, A.M.M.L. van; Hooft, J.J.J. van der; Nijenhuis-de Vries, M.A. ; Labrie, C.W. ; Verkerke, W. ; Geest, H.C. van de; Víquez Zamora, A.M. ; Presa, S. ; Rambla Nebot, J.L. ; Granell, A. ; Hall, R.D. ; Bovy, A.G. - \ 2013
The Plant Cell 25 (2013)8. - ISSN 1040-4651 - p. 3067 - 3078.
mass spectrometry - small molecules - salicylic-acid - key enzyme - flavor - volatiles - biosynthesis - components - odor - gene
Phenylpropanoid volatiles are responsible for the key tomato fruit (Solanum lycopersicum) aroma attribute termed “smoky.” Release of these volatiles from their glycosylated precursors, rather than their biosynthesis, is the major determinant of smoky aroma in cultivated tomato. Using a combinatorial omics approach, we identified the NON-SMOKY GLYCOSYLTRANSFERASE1 (NSGT1) gene. Expression of NSGT1 is induced during fruit ripening, and the encoded enzyme converts the cleavable diglycosides of the smoky-related phenylpropanoid volatiles into noncleavable triglycosides, thereby preventing their deglycosylation and release from tomato fruit upon tissue disruption. In an nsgt1/nsgt1 background, further glycosylation of phenylpropanoid volatile diglycosides does not occur, thereby enabling their cleavage and the release of corresponding volatiles. Using reverse genetics approaches, the NSGT1-mediated glycosylation was shown to be the molecular mechanism underlying the major quantitative trait locus for smoky aroma. Sensory trials with transgenic fruits, in which the inactive nsgt1 was complemented with the functional NSGT1, showed a significant and perceivable reduction in smoky aroma. NSGT1 may be used in a precision breeding strategy toward development of tomato fruits with distinct flavor phenotypes.
The molecular cloning of dihydroartemisinic aldehyde reductase and its implication in artemisinin biosynthesis in Artemisia annua
Ryden, A.M. ; Ruyter-Spira, C.P. ; Quax, W.J. ; Hiroyuki, O. ; Toshiya, M. ; Kayser, O. ; Bouwmeester, H.J. - \ 2010
Planta Medica 76 (2010). - ISSN 0032-0943 - p. 1778 - 1783.
chain dehydrogenases/reductases sdrs - amorpha-4,11-diene synthase - key enzyme - functional assignments - expression - acid - identification - plants - dehydrogenase/reductase - terpenoids
A key point in the biosynthesis of the antimalarial drug artemisinin is the formation of dihydroartemisinic aldehyde which represents the key difference between chemotype specific pathways. This key intermediate is the substrate for several competing enzymes, some of which increase the metabolic flux towards artemisinin, and some of which - as we show in the present study - may have a negative impact on artemisinin production. In an effort to understand the biosynthetic network of artemisinin biosynthesis, extracts of A. annua flowers were investigated and found to contain an enzyme activity competing in a negative sense with artemisinin biosynthesis. The enzyme Red1 is a broad substrate oxidoreductase belonging to the short chain dehydrogenase/reductase family with high affinity for dihydroartemisinic aldehyde and valuable monoterpenoids. Spatial and temporal analysis of cDNA revealed Red1 to be trichome specific. The relevance of Red1 to artemisinin biosynthesis is discussed.
Molecular cloning and characterization of a broad substrate terpenoid oxidoreductase from Artemisia annua.
Ryden, A.M. ; Ruyter-Spira, C.P. ; Litjens, R. ; Takahashi, S. ; Quax, W.J. ; Osada, H. ; Bouwmeester, H.J. ; Kayser, O. - \ 2010
Plant and Cell Physiology 51 (2010)7. - ISSN 0032-0781 - p. 1219 - 1228.
chain dehydrogenases/reductases sdrs - amorpha-4,11-diene synthase - functional assignments - biosynthetic-pathway - essential oil - key enzyme - expression - reductase - peppermint - acid
From Artemisia annua L., a new oxidoreductase (Red 1) was cloned, sequenced and functionally characterized. Through bioinformatics, heterologous protein expression, and enzyme substrate conversion assays, the elucidation of the enzymatic capacities of Red1 was achieved. Red1 acts on monoterpenoids, and in particular functions as a menthone:neomenthol oxidoreductase. The kinetic parameter kcat/Km was determined to be 939 fold more efficient for the reduction of (-)-menthone to (+)-neomenthol, than results previously reported for the menthone:neomenthol reductase from Mentha x piperita. Based on its kinetic properties, the possible use of Red1 in biological crop protection is discussed.
Isoprenoid biosynthesis in Artemisia annua: Cloning and heterologous expression of a germacrene A synthase from a glandular trichome cDNA library
Bertea, C.M. ; Voster, A. ; Verstappen, F.W.A. ; Maffei, M. ; Beekwilder, M.J. ; Bouwmeester, H.J. - \ 2006
Archives of Biochemistry and Biophysics 448 (2006)1-2. - ISSN 0003-9861 - p. 3 - 12.
amorpha-4,11-diene synthase - bacterial expression - arabidopsis-thaliana - diphosphate synthase - molecular-cloning - key enzyme - l. - (e)-beta-farnesene - sesquiterpenes - accumulation
Artemisia annua (Asteraceae) is the source of the anti-malarial compound artemisinin. To elucidate the biosynthetic pathway and to isolate and characterize genes involved in the biosynthesis of terpenoids including artemisinin in A. annua, glandular trichomes were used as an enriched source for biochemical and molecular biological studies. The sequencing of 900 randomly selected clones from a glandular trichome plasmid cDNA library revealed the presence of many ESTs involved in isoprenoid biosynthesis such as enzymes from the methylerythritol phosphate pathway and the mevalonate pathway, amorpha-4,11-diene synthase and other sesquiterpene synthases, monoterpene synthases and two cDNAs showing high similarity to germacrene A synthases. Full-length sequencing of the latter two ESTs resulted in a 1686-bp ORF encoding a protein of 562aa. Upon expression in Escherichia coli, the recombinant protein was inactive with geranyl diphosphate, but catalyzed the cyclization of farnesyl diphosphate to germacrene A. These results demonstrate the potential of the use of A. annua glandular trichomes as a starting material for studying isoprenoid biosynthesis in this plant species.
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