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131.
Tatiana Klempova Eva Basil Alena Kubatova Prof. Milan Certik 《Biotechnology journal》2013,8(7):794-800
Due to increasing demand for natural sources of both polyunsaturated fatty acids (PUFAs) and beta-carotene, 28 Zygomycetes fungal soil isolates were screened for their potential to synthesize these biologically active compounds. Although all fungi produced C18 PUFAs, only nine strains also formed beta-carotene. Although Actinomucor elegans CCF 3218 was the best producer of gamma-linolenic acid (GLA) (251 mg/L), Umbelopsis isabellina CCF 2412 was found to be the most valuable fungus because of the dual production of GLA (217 mg/L) and beta-carotene (40.7 mg/L). The calculated ratio of formed PUFAs provided new insight into activities of individual fatty acid desaturases involved in biosynthetic pathways for various types of PUFAs. The maximal activity of delta-9 desaturase was accompanied by high accumulation of storage lipids in fungal cells. On the other hand, maximal activity of delta-15 desaturase was found in strains synthesizing low amounts of oleic acid due to diminished delta-9 desaturase. Activities of delta-6 desaturase showed competition for fatty acids engaged in n3, n6, and n9 biosynthetic pathways. Such knowledge about fatty acid desaturase activities provides new challenges for the regulation of biotechnological production of PUFAs by Zygomycetes fungi. 相似文献
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134.
Dzubák P Hajdúch M Gazák R Svobodová A Psotová J Walterová D Sedmera P Kren V 《Bioorganic & medicinal chemistry》2006,14(11):3793-3810
Large series of O-alkyl derivatives (methyl and benzyl) of silybin and 2,3-dehydrosilybin was prepared. Selective alkylation of the silybin molecule was systematically investigated. For the first time we present here, for example, preparation of 19-nor-2,3-dehydrosilybin. All prepared silybin/2,3-dehydrosilybin derivatives were tested for cytotoxicity on a panel of drugs sensitive against multidrug resistant cell lines and the ability to inhibit P-glycoprotein mediated efflux activity. We have identified effective and relatively non-cytotoxic inhibitors of P-gp derived from 2,3-dehydrosilybin. Some of them were more effective inhibitors at concentrations lower than a standard P-gp efflux inhibitor cyclosporin A. Another group of 2,3-dehydrosilybin derivatives also had better inhibitory effects on P-gp efflux but a cytotoxicity comparable with that of parent 2,3-dehydrosilybin. Structural requirements for improving inhibitory activity and reducing toxicity of 2,3-dehydrosilybin were established. Effect of E-ring substitution as well as an influence of the substituent size at the C-7-OH position of A-ring on P-gp-inhibitory activity was evaluated for the first time in this study. 相似文献
135.
Topczewska JM Topczewski J Szostak A Solnica-Krezel L Hogan BL 《Gene expression patterns : GEP》2003,3(2):169-171
Delta-Notch signaling is essential for somitogenesis in vertebrate embryos. In a search for genes that control somite formation in zebrafish we have identified two paralogues encoding proteins related to Nrarp (Notch regulated ankyrin repeat protein). Zebrafish nrarp-a and-b encode small proteins with two ankyrin repeat domains. Here, we report the expression patterns of both genes in normal and mutant embryos. 相似文献
136.
Isoamyl alcohol-induced morphological change in Saccharomyces cerevisiae involves increases in mitochondria and cell wall chitin content 总被引:2,自引:0,他引:2
Isoamyl alcohol reduced growth and induced filament formation in Saccharomyces cerevisiae. Isoamyl alcohol-induced filamentation was accompanied by an almost threefold greater increase in the specific activity of succinate dehydrogenase than in untreated cells, which suggested that isoamyl alcohol treatment caused the cells to produce more mitochondria than in normal yeast form proliferation. This was supported by measuring the dry weight of purified, isolated mitochondria. Filaments have an increased chitin content which is distributed over the majority of their surface, and is not confined to bud scars and the chitin ring between mother and daughter cells as in yeast-form cells. 相似文献
137.
Zahra Zangishei Maria Luz Annacondia Heidrun Gundlach Alena Didriksen Julien Bruckmüller Hooman Salari Kirsten Krause German Martinez 《Plant physiology》2022,190(2):1242
Parasitism is a successful life strategy that has evolved independently in several families of vascular plants. The genera Cuscuta and Orobanche represent examples of the two profoundly different groups of parasites: one parasitizing host shoots and the other infecting host roots. In this study, we sequenced and described the overall repertoire of small RNAs from Cuscuta campestris and Orobanche aegyptiaca. We showed that C. campestris contains a number of novel microRNAs (miRNAs) in addition to a conspicuous retention of miRNAs that are typically lacking in other Solanales, while several typically conserved miRNAs seem to have become obsolete in the parasite. One new miRNA appears to be derived from a horizontal gene transfer event. The exploratory analysis of the miRNA population (exploratory due to the absence of a full genomic sequence for reference) from the root parasitic O. aegyptiaca also revealed a loss of a number of miRNAs compared to photosynthetic species from the same order. In summary, our study shows partly similar evolutionary signatures in the RNA silencing machinery in both parasites. Our data bear proof for the dynamism of this regulatory mechanism in parasitic plants.MicroRNAs in parasitic plants reflect their lifestyle. 相似文献
138.
Vivian V. Costa Caio T. Fagundes Deborah F. Valad?o Daniel Cisalpino Ana Carolina F. Dias K��tia D. Silveira Lucas M. Kangussu Thiago V. ��vila Maria Rosa Q. Bonfim Daniela Bonaventura Tarc��lia A. Silva Lirlandia P. Sousa Milene A. Rachid Leda Q. Vieira Gustavo B. Menezes Ana Maria de Paula Alena Atrasheuskaya George Ignatyev Mauro M. Teixeira Danielle G. Souza 《PLoS neglected tropical diseases》2012,6(5)
139.
Extracellular oxidative enzyme production and PAH removal in soil by exploratory mycelium of white rot fungi 总被引:15,自引:0,他引:15
Čeněk Novotný Pavla Erbanová Václav Šašek Alena Kubátová Tomáš Cajthaml Elke Lang Jürgen Krahl František Zadražil 《Biodegradation》1999,10(3):159-168
Selected strains of three species of white rot fungi, Pleurotus ostreatus, Phanerochaete chrysosporium and Trametes versicolor,
were grown in sterilized soil from straw inocula. The respective colonization rates and mycelium density values decreased
in the above mentioned order. Three- and four-ringed PAHs at 50 ppm inhibited growth of fungi in soil to some extent. The
activities of fungal MnP and laccase (units per g dry weight of straw or soil), extracted with 50 mM succinate-lactate buffer
(pH 4.5), were 5 to 20-fold higher in straw compared to soil. The enzyme activities per g dry soil in P. ostreatus and T.
versicolor were similar, in contrast to P. chrysosporium, where they were extremely low. Compared to the aerated controls,
P. ostreatus strains reduced the levels of anthracene, pyrene and phenanthrene by 81–87%, 84–93% and 41–64% within 2 months,
respectively. During degradation of anthracene, all P. ostreatus strains accumulated anthraquinone. PAH removal rates in P.
chrysosporium and T. versicolor soil cultures were much lower. 相似文献
140.