189 research outputs found

    Taxol Precursor Production in Physcomitrella patens

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    Taxol is a cancer fighting drug that was initially isolated from the Pacific Yew. However, the isolation process is not very efficient and the tree is being excessively harvested and faces extinction. To synthetically make Taxol is an inefficient and costly process. If the precursor taxadiene-5 alpha-acetoxy-10 beta-ol can be produced with ease, then the synthetic modification of that precursor would be an efficient way to produce the potent cancer fighting drug. Several genes from the Pacific Yew were isolated and amplified so that they could be inserted into the moss Physcomitrella patens. Using competent E. coli cells as entry vectors, the genes were transferred so that the metabolic pathway responsible for taxadiene-5 alpha-acetoxy-10 beta-ol synthesis could be replicated in Physcomitrella patens. When the final transfer was made to the moss, a transient expression of the genes resulted in small amounts of product being obtained. After gas chromatography mass spectrometry analysis, the chromatogram plots showed a few more promising peaks representing other Taxol precursors. With a permanent transfer to the moss, a much larger sample could be analyzed and more Taxol precursor could be produced

    The feasibility of producing oil palm with altered lignin content to control Ganoderma disease

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    Oil palm is a major crop which is grown for the production of vegetable oil used in foods, cosmetics and biodiesel. The palm is of major economic importance in southeast Asia where it is grown extensively in Malaysia and Indonesia. There is concern about Ganoderma rots of oil palm which need to be controlled to prevent major infection. However, the basic mechanism of white-rot infection has been ignored. White rot implies that fungi attack the lignin component of woody tissue leaving the white cellulose exposed. The fungus grows within palms by utilizing cellulose in the tree. By altering the lignin fraction of oil palm losses may be reduced. Methods for altering lignin in plants are reviewed here to indicate how similar transformations could be attempted for oil palm. In addition, progress in transforming oil palm is described. Lignin is extremely complex and this may explain why it has not been studied in oil palm. Some crops transformed with Bacillus thuringiensis toxin genes have increased lignin and modified oil palm have been produced using B. thuringiensis genes. These require to be tested for lignin concentration and structure. The nomenclature of the disease organism is discussed. The prospects for altered lignin oil palm are considered herein.Fundação para a Ciência e a Tecnologia (FCT) - SFRH ⁄ BPD ⁄ 34879 ⁄ 200

    The Division of Federal Spending for Environmental Programs and Space Agencies

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    With the rise of privately owned space programs/organizations, such as SpaceX, the amount of federal funding towards NASA has come into question. In the modern day, the government is providing money to an organization that is being matched by privately funded organizations, like SpaceX, when there are more pressing matters affecting us here on our own planet. One of these pressing matters is environmental conservation. The Environmental Protection Agency (EPA) is researching ways to save life on our planet, such as ways to stop climate change, stop global warming, and reduce carbon dioxide, which will affect us in the near future more than events occurring in space. The EPA works at preserving nature and the climate due to its ability to drastically and rapidly change life while space exploration is changing our lives at a slower rate. Therefore, it is more important to fund agencies like the EPA, rather than NASA, thus meaning that the EPA should get an increase in funding, while NASA should receive less

    PhMYB4 fine-tunes the floral volatile signature of Petunia×hybrida through PhC4H

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    In Petunia×hybrida cv ‘Mitchell Diploid’ (MD), floral volatile benzenoid/phenylpropanoid (FVBP) biosynthesis is controlled spatially, developmentally, and daily at molecular, metabolic, and biochemical levels. Multiple genes have been shown to encode proteins that either directly catalyse a biochemical reaction yielding FVBP compounds or are involved in metabolite flux prior to the formation of FVBP compounds. It was hypothesized that multiple transcription factors are involved in the precise regulation of all necessary genes, resulting in the specific volatile signature of MD flowers. After acquiring all available petunia transcript sequences with homology to Arabidopsis thaliana R2R3-MYB transcription factors, PhMYB4 (named for its close identity to AtMYB4) was identified, cloned, and characterized. PhMYB4 transcripts accumulate to relatively high levels in floral tissues at anthesis and throughout open flower stages, which coincides with the spatial and developmental distribution of FVBP production and emission. Upon RNAi suppression of PhMYB4 (ir-PhMYB4) both petunia CINNAMATE-4-HYDROXYLASE (PhC4H1 and PhC4H2) gene transcript levels were significantly increased. In addition, ir-PhMYB4 plants emit higher levels of FVBP compounds derived from p-coumaric acid (isoeugenol and eugenol) compared with MD. Together, these results indicate that PhMYB4 functions in the repression of C4H transcription, indirectly controlling the balance of FVBP production in petunia floral tissue (i.e. fine-tunes)

    Downregulation of Cinnamyl-Alcohol Dehydrogenase in Switchgrass by RNA Silencing Results in Enhanced Glucose Release after Cellulase Treatment

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    Cinnamyl alcohol dehydrogenase (CAD) catalyzes the last step in monolignol biosynthesis and genetic evidence indicates CAD deficiency in grasses both decreases overall lignin, alters lignin structure and increases enzymatic recovery of sugars. To ascertain the effect of CAD downregulation in switchgrass, RNA mediated silencing of CAD was induced through Agrobacterium mediated transformation of cv. “Alamo” with an inverted repeat construct containing a fragment derived from the coding sequence of PviCAD2. The resulting primary transformants accumulated less CAD RNA transcript and protein than control transformants and were demonstrated to be stably transformed with between 1 and 5 copies of the T-DNA. CAD activity against coniferaldehyde, and sinapaldehyde in stems of silenced lines was significantly reduced as was overall lignin and cutin. Glucose release from ground samples pretreated with ammonium hydroxide and digested with cellulases was greater than in control transformants. When stained with the lignin and cutin specific stain phloroglucinol-HCl the staining intensity of one line indicated greater incorporation of hydroxycinnamyl aldehydes in the lignin

    Imbalanced Lignin Biosynthesis Promotes the Sexual Reproduction of Homothallic Oomycete Pathogens

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    Lignin is incorporated into plant cell walls to maintain plant architecture and to ensure long-distance water transport. Lignin composition affects the industrial value of plant material for forage, wood and paper production, and biofuel technologies. Industrial demands have resulted in an increase in the use of genetic engineering to modify lignified plant cell wall composition. However, the interaction of the resulting plants with the environment must be analyzed carefully to ensure that there are no undesirable side effects of lignin modification. We show here that Arabidopsis thaliana mutants with impaired 5-hydroxyguaiacyl O-methyltransferase (known as caffeate O-methyltransferase; COMT) function were more susceptible to various bacterial and fungal pathogens. Unexpectedly, asexual sporulation of the downy mildew pathogen, Hyaloperonospora arabidopsidis, was impaired on these mutants. Enhanced resistance to downy mildew was not correlated with increased plant defense responses in comt1 mutants but coincided with a higher frequency of oomycete sexual reproduction within mutant tissues. Comt1 mutants but not wild-type Arabidopsis accumulated soluble 2-O-5-hydroxyferuloyl-l-malate. The compound weakened mycelium vigor and promoted sexual oomycete reproduction when applied to a homothallic oomycete in vitro. These findings suggested that the accumulation of 2-O-5-hydroxyferuloyl-l-malate accounted for the observed comt1 mutant phenotypes during the interaction with H. arabidopsidis. Taken together, our study shows that an artificial downregulation of COMT can drastically alter the interaction of a plant with the biotic environment
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