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Jinxin Li, Shujie Liu, Juan Wang, Jing Li, Dahui Liu, Jianli Li, Wenyuan Gao
In this work, we selected three fungi strains (Aspergillus niger, Aspergillus flavus and Aspergillus oryzae) as elicitors prepared from mycelium or fermentation broth to improve ginsenosides production in adventitious roots culture. The results showed that ginsenosides production (29.90±4.67mgg(-1)) was significantly enhanced upon elicitation with 200mgL(-1)A. niger elicitor prepared from mycelium, which was 3.52-fold of untreated group. HPLC-ESI-MS(n) analysis was performed, showing that ginsenoside Rb3 was present after treatment with the A...
October 13, 2016: Journal of Biotechnology
Huihong Guo, Rufang Li, Shibiao Liu, Na Zhao, Shuo Han, Mengmeng Lu, Xiaomin Liu, Xinli Xia
Gynostemma pentaphyllum (Thunb.) Makino is a perennial medicinal herb widely distributed in China. This herb contains important medicinal components called gypenosides, which belong to dammarane-type triterpenoid saponins. Squalene epoxidase (SE, EC catalyzes the epoxidation of squalene to form oxidosqualene and is a key regulatory enzyme in triterpenoid saponin biosynthesis. In this study, a SE gene designated as GpSE1 was isolated from G. pentaphyllum leaves. The deduced protein sequence of GpSE1 contained two conserved domains involved in the catalytic function of SE...
October 6, 2016: Plant Physiology and Biochemistry: PPB
Tibor András Rokob
Oxygenation of aromatic rings using O2 is catalyzed by several non-heme carboxylate-bridged diiron enzymes. In order to provide a general mechanistic description for these reactions, computational studies were carried out at the ONIOM(B3LYP/BP86/Amber) level on the non-heme diiron enzyme benzoyl coenzyme A epoxidase BoxB. The calculations revealed four possible pathways for attacking the aromatic ring: a) electrophilic (2e(-)) attack by a bis(μ-oxo)-diiron(IV) species (Q pathway); b) electrophilic (2e(-)) attack via the σ* orbital of a μ-η(2):η(2)-peroxo-diiron(III) intermediate (Pσ* pathway); c) radical (1e(-)) attack via the π*-orbital of a superoxo-diiron(II,III) species (Pπ* pathway); d) radical (1e(-)) attack of a partially quenched diiron(IV) intermediate (Q' pathway)...
September 28, 2016: Journal of the American Chemical Society
Jianli Li, Shujie Liu, Juan Wang, Jing Li, Jinxin Li, Wenyuan Gao
This study reports the best culture conditions for roots growth and accumulation of active components by optimizing the parameters. Glycyrrhiza uralensis adventitious roots metabolites were significantly increased after adding Saccharomyces cerevisiae and Meyerozyma guilliermondii. The highest contents of polysaccharide, glycyrrhizic acid, glycyrrhetinic acid and total flavonoids were obtained in Meyerozyma guilliermondii group, the content of glycyrrhizic acid was 5.3-fold higher than the control. In control and treatment groups, twelve compounds were identified by high performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS),among which, some new compounds have been detected in elicitor groups including 5,7-Dihydroxyflavanone, glycyrrhisoflavanone, licorice saponin J2, uralsaponin B, (3R)-vestitol, uralenol...
September 20, 2016: Biotechnology and Applied Biochemistry
Zhirong Li, Graham Peers, Rachel M Dent, Yong Bai, Scarlett Y Yang, Wiebke Apel, Lauriebeth Leonelli, Krishna K Niyogi
Plants, algae and cyanobacteria need to regulate photosynthetic light harvesting in response to the constantly changing light environment. Rapid adjustments are required to maintain fitness because of a trade-off between efficient solar energy conversion and photoprotection. The xanthophyll cycle, in which the carotenoid pigment violaxanthin is reversibly converted into zeaxanthin, is ubiquitous among green algae and plants and is necessary for the regulation of light harvesting, protection from oxidative stress and adaptation to different light conditions(1,2)...
2016: Nature Plants
Jing Xu, Zhigang Li, Haorui Yang, Xiaohong Yang, Cuixia Chen, Hui Li
Violaxanthin de-epoxidase (VDE) has a critical role in the carotenoid biosynthesis pathway, which is involved in protecting the photosynthesis apparatus from damage caused by excessive light. Here, a VDE gene in maize, ZmVDE1, was cloned and shown to have functional domains in common with the gramineous VDE protein. Candidate gene association analysis indicated that no polymorphic sites in ZmVDE1 were significant association with any of the examined carotenoid-related traits at P = 0.05 in an association panel containing 155 maize inbred lines...
2016: Frontiers in Genetics
Qiusheng Kong, Jingxian Yuan, Lingyun Gao, Peng Liu, Lei Cao, Yuan Huang, Liqiang Zhao, Huifang Lv, Zhilong Bie
Rootstocks have comprehensive effects on lycopene accumulation in grafted watermelon fruits. However, little is known about lycopene metabolic regulation in grafted watermelon. To address this problem, parallel changes in lycopene contents and the expression of its metabolic genes were analyzed during the fruit ripening of nongrafted watermelon and watermelon grafted onto bottle gourd, pumpkin, and wild watermelon. Results showed that rootstocks mediated the transcriptional regulations of lycopene accumulation in different ways...
January 1, 2017: Food Chemistry
Ju Yeun Lee, Sei Mee Yoon, Eun Ju Choi, Jinu Lee
Terbinafine is an antifungal agent that selectively inhibits fungal sterol synthesis by blocking squalene epoxidase. We evaluated the effect of terbinafine on gap junctional intercellular communication (GJIC). Fluorescence recovery after photobleaching (FRAP) and I-YFP GJIC assays revealed that terbinafine inhibits GJIC in a reversible and dose-dependent manner in FRT-Cx43 and LN215 cells. Treatment with terbinafine did not affect Cx43 phosphorylation status or intracellular Ca(2+) concentration, well-known action mechanisms of various GJIC blockers...
September 15, 2016: Toxicology and Applied Pharmacology
Heqiang Huo, Isabelle M Henry, Eric R Coppoolse, Miriam Verhoef-Post, Johan W Schut, Han de Rooij, Aat Vogelaar, Ronny V L Joosen, Leo Woudenberg, Luca Comai, Kent J Bradford
Lettuce (Lactuca sativa) seeds exhibit thermoinhibition, or failure to complete germination when imbibed at warm temperatures. Chemical mutagenesis was employed to develop lettuce lines that exhibit germination thermotolerance. Two independent thermotolerant lettuce seed mutant lines, TG01 and TG10, were generated through ethyl methanesulfonate mutagenesis. Genetic and physiological analyses indicated that these two mutations were allelic and recessive. To identify the causal gene(s), we applied bulked segregant analysis by whole genome sequencing...
July 13, 2016: Plant Journal: for Cell and Molecular Biology
Syed Haider, Alan McIntyre, Ruud G P M van Stiphout, Laura M Winchester, Simon Wigfield, Adrian L Harris, Francesca M Buffa
BACKGROUND: Altered metabolism is a hallmark of cancer. However, the role of genomic changes in metabolic genes driving the tumour metabolic shift remains to be elucidated. Here, we have investigated the genomic and transcriptomic changes underlying this shift across ten different cancer types. RESULTS: A systematic pan-cancer analysis of 6538 tumour/normal samples covering ten major cancer types identified a core metabolic signature of 44 genes that exhibit high frequency somatic copy number gains/amplifications (>20 % cases) associated with increased mRNA expression (ρ > 0...
2016: Genome Biology
Animesh Acharjee, Bjorn Kloosterman, Richard G F Visser, Chris Maliepaard
BACKGROUND: In order to find genetic and metabolic pathways related to phenotypic traits of interest, we analyzed gene expression data, metabolite data obtained with GC-MS and LC-MS, proteomics data and a selected set of tuber quality phenotypic data from a diploid segregating mapping population of potato. In this study we present an approach to integrate these ~ omics data sets for the purpose of predicting phenotypic traits. This gives us networks of relatively small sets of interrelated ~ omics variables that can predict, with higher accuracy, a quality trait of interest...
2016: BMC Bioinformatics
Sabrina Gonzalez-Jorge, Payam Mehrshahi, Maria Magallanes-Lundback, Alexander E Lipka, Ruthie Angelovici, Michael A Gore, Dean DellaPenna
Elucidation of the carotenoid biosynthetic pathway has enabled altering the composition and content of carotenoids in various plants, but to achieve desired nutritional impacts, the genetic components regulating carotenoid homeostasis in seed, the plant organ consumed in greatest abundance, must be elucidated. We used a combination of linkage mapping, genome-wide association studies (GWAS), and pathway-level analysis to identify nine loci that impact the natural variation of seed carotenoids in Arabidopsis (Arabidopsis thaliana)...
July 2016: Plant Physiology
Erik Ingmar Hallin, Mahmudul Hasan, Kuo Guo, Hans-Erik Åkerlund
Violaxanthin de-epoxidase (VDE) is a conditionally soluble enzyme located in the thylakoid lumen and catalyses the conversion of violaxanthin to antheraxanthin and zeaxanthin, which are located in the thylakoid membrane. These reactions occur when the plant or algae are exposed to saturating light and the zeaxanthin formed is involved in the process of non-photochemical quenching that protects the photosynthetic machinery during stress. Oversaturation by light results in a reduction of the pH inside the thylakoids, which in turn activates VDE and the de-epoxidation of violaxanthin...
July 2016: Photosynthesis Research
Chengcheng Zhao, Xin Gao, Xinbin Liu, Yong Wang, Shengli Yang, Fengqing Wang, Yuhong Ren
Ginsenosides from the edible and medicinal plant ginseng have demonstrated various pharmacological activities. However, producing ginsenoside efficiently remains a challenge. Engineering metabolic pathways through protein assembly in yeast is a promising way for ginsenoside production. In the biosynthetic pathway of ginsenosides, dammarenediol-II synthase and squalene epoxidase are two key enzymes that determine the production rate of the dammarane-type ginsenoside precursor dammarenediol-II. In this work, a strategy to enhance the biosynthesis of dammarenediol-II in Pichia pastoris was developed by the self-assembly of the two key enzymes via protein-protein interaction...
May 4, 2016: Journal of Agricultural and Food Chemistry
Tsuyoshi Yamamoto, Yuta Tsunematsu, Kodai Hara, Tomohiro Suzuki, Shinji Kishimoto, Hirokazu Kawagishi, Hiroshi Noguchi, Hiroshi Hashimoto, Yi Tang, Kinya Hotta, Kenji Watanabe
Geometric isomerization can expand the scope of biological activities of natural products. The observed chemical diversity among the pseurotin-type fungal secondary metabolites is in part generated by a trans to cis isomerization of an olefin. In vitro characterizations of pseurotin biosynthetic enzymes revealed that the glutathione S-transferase PsoE requires participation of the bifunctional C-methyltransferase/epoxidase PsoF to complete the trans to cis isomerization of the pathway intermediate presynerazol...
May 17, 2016: Angewandte Chemie
Anja Beer, Matthias Juhas, Claudia Büchel
The diatom Cyclotella meneghiniana Kütz. (SAG 1020-a) was cultured under high-light (HL) and low-light (LL) conditions with either high (12 μM) or low (1 μM) iron in the media. Changes in cell morphology, especially cell volume and chloroplast size, were observed in cells grown under low iron. In contrast, HL had a much stronger influence on the photosynthetic apparatus. PSII function was unimpaired under lowered iron supply, but its quantum efficiency and reoxidation rate were reduced under HL conditions...
December 2011: Journal of Phycology
Erik Ingmar Hallin, Kuo Guo, Hans-Erik Åkerlund
Photosynthetic organisms need protection against excessive light. By using non-photochemical quenching, where the excess light is converted into heat, the organism can survive at higher light intensities. This process is partly initiated by the formation of zeaxanthin, which is achieved by the de-epoxidation of violaxanthin and antheraxanthin to zeaxanthin. This reaction is catalyzed by violaxanthin de-epoxidase (VDE). VDE consists of three domains of which the central lipocalin-like domain has been the most characterized...
August 2016: Physiologia Plantarum
Ulrike Eilers, Lars Dietzel, Jürgen Breitenbach, Claudia Büchel, Gerhard Sandmann
Phaeodactylum tricornutum like other diatoms synthesizes fucoxanthin and diadinoxanthin as major carotenoid end products. The genes involved have recently been assigned for early pathway steps. Beyond β-carotene, only gene candidates for β-carotene hydroxylase, zeaxanthin epoxidase and zeaxanthin de-epoxidase have been proposed from the available genome sequence. The two latter enzymes may be involved in the two different xanthophyll cycles which operate in P. tricornutum. The function of three putative zeaxanthin epoxidase genes (zep) was addressed by pathway complementation in the Arabidopsis thaliana Zep mutant npq2...
March 15, 2016: Journal of Plant Physiology
Marcelo Dutra Arbo, Simone Melega, Regina Stöber, Markus Schug, Eugen Rempel, Jörg Rahnenführer, Patricio Godoy, Raymond Reif, Cristina Cadenas, Maria de Lourdes Bastos, Helena Carmo, Jan G Hengstler
The piperazine derivatives most frequently consumed for recreational purposes are 1-benzylpiperazine, 1-(3,4-methylenedioxybenzyl) piperazine, 1-(3-trifluoromethylphenyl) piperazine and 1-(4-methoxyphenyl) piperazine. Generally, they are consumed as capsules, tablets or pills but also in powder or liquid forms. Currently, the precise mechanism by which piperazine designer drugs induce hepatotoxicity and whether they act by a common pathway is unclear. To answer this question, we performed a gene array study with rat hepatocytes incubated with the four designer drugs...
January 28, 2016: Archives of Toxicology
Jinxin Li, Juan Wang, Xiaolei Wu, Dahui Liu, Jing Li, Jianli Li, Shujie Liu, Wenyuan Gao
Panax notoginseng, an important herbal medicine, has wide uses for its bioactive compounds and health function. In this work, we compared the content of saponin in cultivation and adventitious root. The total content of saponins in adventitious root (8.48 mg· g(-1) ) was found lower thanin the native one (3-year-old) (34.34 mg· g(-1) ). In order to enhance the content of bioactive compounds, we applied elicitors jasmonic acid (JA) and methyl dihydrojasmonate (MDJ) to the adventitious root culture. It was observed that the highest total content of saponins (71...
January 18, 2016: Biotechnology and Applied Biochemistry
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