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Squalene synthase

Guang Zhang, Ang Ren, Fengli Wu, Hanshou Yu, Liang Shi, Mingwen Zhao
OBJECTIVE: To investigate the effects of ethylene, in the form of ethephon (2-chloroethylphosphonic acid), on mycelial growth and ganoderic acid (GA) accumulation in the higher basidiomycete Ganoderma lucidum. RESULTS: Treatment with both 10 and 15 mM ethephon enhanced the growth of G. lucidum on solid CYM plates and in CYM liquid medium. After optimization using response surface methodology, GA reached 33 mg/g dry cell weight (DW), an increase of 90 %, compared with the control...
October 22, 2016: Biotechnology Letters
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
Ming Liu, Li-Na Li, Yi-Ting Pan, Jian-Qiang Kong
As the first step of ongoing efforts to investigate the genes responsible for the biosynthesis of steroidal saponins in the medicinal plant Ornithogalum caudatum, this investigation reported the cDNA isolation, prokaryotic expression and functional characterization of squalene synthase (SQS) gene from O. caudatum for the first time. Specifically, two unigenes showing high sequence identity to SQS were retrieved from RNA-Taq data, and then a full-length OcSQS1 corresponding to the two unigenes was isolated from O...
October 7, 2016: Protein Expression and Purification
Sun Young Choi, Hyun Jeong Lee, Jaeyeon Choi, Jiye Kim, Sang Jun Sim, Youngsoon Um, Yunje Kim, Taek Soon Lee, Jay D Keasling, Han Min Woo
BACKGROUND: Metabolic engineering of cyanobacteria has enabled photosynthetic conversion of CO2 to value-added chemicals as bio-solar cell factories. However, the production levels of isoprenoids in engineered cyanobacteria were quite low, compared to other microbial hosts. Therefore, modular optimization of multiple gene expressions for metabolic engineering of cyanobacteria is required for the production of farnesyl diphosphate-derived isoprenoids from CO2. RESULTS: Here, we engineered Synechococcus elongatus PCC 7942 with modular metabolic pathways consisting of the methylerythritol phosphate pathway enzymes and the amorphadiene synthase for production of amorpha-4,11-diene, resulting in significantly increased levels (23-fold) of amorpha-4,11-diene (19...
2016: Biotechnology for Biofuels
Nobutaka Suzuki, Tatsuo Ito, Hisanori Matsui, Masayuki Takizawa
TAK-475 (lapaquistat acetate) and its active metabolite-I (TAK-475 M-I) inhibit squalene synthase, which catalyzes the conversion of farnesyl diphosphate (FPP) to squalene. FPP is a substrate for synthesis of other mevalonate-derived isoprenoids (MDIs) such as farnesol (FOH), geranlygeranyl diphosphate (GGPP), and geranylgeraniol. In patients with MKD, a rare autosomal recessive disorder, defective activity of mevalonate kinase leads to a shortage of MDIs. MDIs especially GGPP are required for prenylation of proteins, which is a posttranslation modification necessary for proper functioning of proteins like small guanosine triphosphatases...
2016: SpringerPlus
Panpan Zhang, Xiaoying Cao, Changgen Li, Zhujun Zheng, Sun Yong, Ji-Hong Jiang
Squalene synthase catalyzes the condensation of 2 molecules of farnesyl diphosphate to produce squalene, the first committed precursor for sterol, brassinosteroid, and triterpene biosynthesis. A squalene synthase gene, designated IoSQS, was isolated from Inonotus obliquus, a medicinal mushroom that produces a plethora of bioactive triterpenes. IoSQS complementary DNA was found to contain an open reading frame of 1476 bp, encoding a protein of 491 amino acids with a calculated molecular mass of 55.85 kDa. The IoSQS genomic DNA sequence consisted of 1813 bp and contained 4 exons and 3 introns...
2016: International Journal of Medicinal Mushrooms
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
Maryam Hosseinpour, Mohsen Mobini-Dehkordi, Hossein Teimori
INTRODUCTION: Over expression of squalene synthase gene causes induction of growth tumour and reduction of apoptosis. This gene which is conserved between Saccharomyces cerevisiae yeast and humans, is named (ERG9). AIM: In this work, we studied the effect of Matricaria recutita extract on ERG9 gene (squalene synthase) expression in S.cerevisiae which was used as organism model in cancer therapy. MATERIALS AND METHODS: S. cerevisiae was cultured in YPD medium plus 0,250, 1000 and 3000 μg/ml of Matricaria recutita extract and we evaluated the (ERG9) gene expression by Real-time RT-PCR method after 24 hours...
July 2016: Journal of Clinical and Diagnostic Research: JCDR
Qixian Rong, Dan Jiang, Yijun Chen, Ye Shen, Qingjun Yuan, Huixin Lin, Liangping Zha, Yan Zhang, Luqi Huang
Salvia miltiorrhiza Bunge, which is also known as a traditional Chinese herbal medicine, is widely studied for its ability to accumulate the diterpene quinone Tanshinones. In addition to producing a variety of diterpene quinone, S. miltiorrhiza Bunge also accumulates sterol, brassinosteroid and triterpenoids. During their biosynthesis, squalene synthase (SQS, EC converts two molecules of the hydrophilic substrate farnesyl diphosphate (FPP) into a hydrophobic product, squalene. In the present study, cloning and characterization of S...
2016: Frontiers in Plant Science
Bhusan Gurung, Pardeep K Bhardwaj, Narayan C Talukdar
In the present study, suppression subtractive hybridization (SSH) strategy was used to identify rare and differentially expressed transcripts in leaf and rhizome tissues of Panax sokpayensis. Out of 1102 randomly picked clones, 513 and 374 high quality expressed sequenced tags (ESTs) were generated from leaf and rhizome subtractive libraries, respectively. Out of them, 64.92 % ESTs from leaf and 69.26 % ESTs from rhizome SSH libraries were assembled into different functional categories, while others were of unknown function...
September 1, 2016: Functional & Integrative Genomics
Elise K Pasoreck, Jin Su, Ian M Silverman, Sager J Gosai, Brian D Gregory, Joshua S Yuan, Henry Daniell
The impact of metabolic engineering on nontarget pathways and outcomes of metabolic engineering from different genomes are poorly understood questions. Therefore, squalene biosynthesis genes FARNESYL DIPHOSPHATE SYNTHASE (FPS) and SQUALENE SYNTHASE (SQS) were engineered via the Nicotiana tabacum chloroplast (C), nuclear (N) or both (CN) genomes to promote squalene biosynthesis. SQS levels were ~4300-fold higher in C and CN lines than in N, but all accumulated ~150-fold higher squalene due to substrate or storage limitations...
September 2016: Plant Biotechnology Journal
Kristin B Linscott, Thomas D Niehaus, Xun Zhuang, Stephen A Bell, Joe Chappell
Squalene synthase catalyzes the first committed step in sterol biosynthesis and consists of both an amino-terminal catalytic domain and a carboxy-terminal domain tethering the enzyme to the ER membrane. While the overall architecture of this enzyme is identical in eukaryotes, it was previously shown that plant and animal genes cannot complement a squalene synthase knockout mutation in yeast unless the carboxy-terminal domain is swapped for one of fungal origin. This implied a unique component of the fungal carboxy-terminal domain was responsible for the complementation phenotype...
September 2016: Biochimica et Biophysica Acta
Elizabeth A Rondini, Zofia Duniec-Dmuchowski, Daniela Cukovic, Alan A Dombkowski, Thomas A Kocarek
Squalene synthase inhibitors (SSIs), such as squalestatin 1 (SQ1), reduce cholesterol biosynthesis but cause the accumulation of isoprenoids derived from farnesyl pyrophosphate (FPP), which can modulate the activity of nuclear receptors, including the constitutive androstane receptor (CAR), farnesoid X receptor, and peroxisome proliferator-activated receptors (PPARs). In comparison, 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (e.g., pravastatin) inhibit production of both cholesterol and nonsterol isoprenoids...
August 2016: Journal of Pharmacology and Experimental Therapeutics
Kenichi Shimada, Rachid Skouta, Anna Kaplan, Wan Seok Yang, Miki Hayano, Scott J Dixon, Lewis M Brown, Carlos A Valenzuela, Adam J Wolpaw, Brent R Stockwell
Apoptosis is one type of programmed cell death. Increasingly, non-apoptotic cell death is recognized as being genetically controlled, or 'regulated'. However, the full extent and diversity of alternative cell death mechanisms remain uncharted. Here we surveyed the landscape of pharmacologically accessible cell death mechanisms. In an examination of 56 caspase-independent lethal compounds, modulatory profiling showed that 10 compounds induced three different types of regulated non-apoptotic cell death. Optimization of one of those ten resulted in the discovery of FIN56, a specific inducer of ferroptosis...
July 2016: Nature Chemical Biology
Huan-Jun Li, Yi-Long He, De-Huai Zhang, Tong-Hui Yue, Lu-Xi Jiang, Na Li, Jun-Wei Xu
The Vitreoscilla hemoglobin (VHb) gene was expressed in Ganoderma lucidum to enhance antitumor ganoderic acid (GA) production. The effects of VHb expression on the accumulation of GAs and lanosterol (intermediate) and the transcription of GA biosynthesis genes were also investigated. In VHb-expressing G. lucidum, the maximum concentrations of four individual GAs (GA-S, GA-T, GA-Mk and GA-Me) were 19.1±1.8, 34.6±2.1, 191.5±13.1 and 45.2±2.8μg/100mg dry weight, respectively, which were 1.4-, 2.2, 1.9- and 2...
June 10, 2016: Journal of Biotechnology
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
Hem R Thapa, Mandar T Naik, Shigeru Okada, Kentaro Takada, István Molnár, Yuquan Xu, Timothy P Devarenne
The green microalga Botryococcus braunii is considered a promising biofuel feedstock producer due to its prodigious accumulation of hydrocarbon oils that can be converted into fuels. B. braunii Race L produces the C40 tetraterpenoid hydrocarbon lycopadiene via an uncharacterized biosynthetic pathway. Structural similarities suggest this pathway follows a biosynthetic mechanism analogous to that of C30 squalene. Confirming this hypothesis, the current study identifies C20 geranylgeranyl diphosphate (GGPP) as a precursor for lycopaoctaene biosynthesis, the first committed intermediate in the production of lycopadiene...
2016: Nature Communications
Radhakrishnan Narayanaswamy, Azizul Isha, Lam Kok Wai, Intan Safinar Ismail
BACKGROUND: Clinacanthus nutans (Burm. f.) Lindau has gained popularity among Malaysians as a traditional plant for anti-inflammatory activity. OBJECTIVE: This prompted us to carry out the present study on a selected 11 constituents of C. nutans which are clinacoside A-C, cycloclinacoside A1, shaftoside, vitexin, orientin, isovitexin, isoorientin, lupeol and β-sitosterol. MATERIALS AND METHODS: Selected 11 constituents of C. nutans were evaluated on the docking behavior of xanthine oxidase (XO), nitric oxide synthase (NOS), human neutrophil elastase (HNE), matrix metalloproteinase (MMP 2 and 9), and squalene synthase (SQS) using Discovery Studio Version 3...
January 2016: Pharmacognosy Magazine
Inga Marie Aasen, Helga Ertesvåg, Tonje Marita Bjerkan Heggeset, Bin Liu, Trygve Brautaset, Olav Vadstein, Trond E Ellingsen
Thraustochytrids have been applied for industrial production of the omega-3 fatty acid docosahexaenoic (DHA) since the 1990s. During more than 20 years of research on this group of marine, heterotrophic microorganisms, considerable increases in DHA productivities have been obtained by process and medium optimization. Strains of thraustochytrids also produce high levels of squalene and carotenoids, two other commercially interesting compounds with a rapidly growing market potential, but where yet few studies on process optimization have been reported...
May 2016: Applied Microbiology and Biotechnology
T Ebihara, T Takeuchi, Y Moriya, Y Tagawa, T Kondo, T Moriwaki, S Asahi
TAK-475 (lapaquistat acetate) is a squalene synthase inhibitor and M-I is a pharmacologically active metabolite of TAK-475. Preclinical pharmacokinetic studies have demonstrated that most of the dosed TAK-475 was hydrolyzed to M-I during the absorption process and the concentrations of M-I in the liver, the main organ of cholesterol biosynthesis, were much higher than those in the plasma after oral administration to rats. In the present study, the mechanism of the hepatic uptake of M-I was investigated.The uptake studies of (14)C-labeled M-I into rat and human hepatocytes indicated that the uptakes of M-I were concentrative, temperature-dependent and saturable in both species with Km values of 4...
June 2016: Drug Research
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