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Sample records for astaxanthin biosynthesis pathway

  1. The astaxanthin dideoxyglycoside biosynthesis pathway in Sphingomonas sp. PB304.

    Science.gov (United States)

    Kim, Se Hyeuk; Kim, Jin Ho; Lee, Bun Yeol; Lee, Pyung Cheon

    2014-12-01

    A major carotenoid in Sphingomonas sp. PB304, originally isolated from a river in Daejon City, South Korea, was identified as astaxanthin dideoxyglycoside. Gene clusters encoding the astaxanthin dideoxyglycoside biosynthetic enzymes were identified by screening Sphingomonas sp. PB304 fosmid libraries using degenerate probes that harbor highly conserved sequences from the Sphigomonas elodea-derived crtI and Nostoc sp. PCC 7120-dervied crtW genes. Selected positive gene clusters were fully sequenced and annotated, revealing genes encoding six putative carotenogenic enzymes: phytoene synthase (CrtB), phytoene desaturase (CrtI), lycopene cyclase (CrtY), carotene hydroxylase (CrtZ), carotene ketolase (CrtW), and glycosyltransferase (CrtX). All of the carotenogenic enzymes, except for CrtX, were functional in the recombinant host Escherichia coli expressing synthetic carotenogenic modules from Pantoea agglomerans. CrtX did not take up UDP-glucose or GDP-fucose as sugar substrates during the in vitro reaction. Although no direct experimental evidence was obtained for the function of Sphingomonas sp. PB304 CrtX, it can be categorized as a putative deoxyglycosyltransferase based on the presence of astaxanthin dideoxyglycoside in Sphingomonas sp. PB304, a putative corresponding gene in the carotenoid biosynthetic gene cluster, and high amino acid sequence homology to the existing glycosyltransferases. Therefore, we propose that astaxanthin dideoxyglycoside can be synthesized in Sphingomonas sp. PB304 via sequential reactions of six pathway enzymes, including CrtX on the phytoene intermediate. PMID:25193422

  2. The astaxanthin dideoxyglycoside biosynthesis pathway in Sphingomonas sp. PB304

    DEFF Research Database (Denmark)

    Kim, Se Hyeuk; Kim, Jin Ho; Lee, Bun Yeol;

    2014-01-01

    A major carotenoid in Sphingomonas sp. PB304, originally isolated from a river in Daejon City, South Korea, was identified as astaxanthin dideoxyglycoside. Gene clusters encoding the astaxanthin dideoxyglycoside biosynthetic enzymes were identified by screening Sphingomonas sp. PB304 fosmid...... of astaxanthin dideoxyglycoside in Sphingomonas sp. PB304, a putative corresponding gene in the carotenoid biosynthetic gene cluster, and high amino acid sequence homology to the existing glycosyltransferases. Therefore, we propose that astaxanthin dideoxyglycoside can be synthesized in Sphingomonas sp. PB304...

  3. "Glucose and ethanol-dependent transcriptional regulation of the astaxanthin biosynthesis pathway in Xanthophyllomyces dendrorhous"

    Directory of Open Access Journals (Sweden)

    Cifuentes Víctor

    2011-08-01

    Full Text Available Abstract Background The yeast Xanthophyllomyces dendrorhous is one of the most promising and economically attractive natural sources of astaxanthin. The biosynthesis of this valuable carotenoid is a complex process for which the regulatory mechanisms remain mostly unknown. Several studies have shown a strong correlation between the carbon source present in the medium and the amount of pigments synthesized. Carotenoid production is especially low when high glucose concentrations are used in the medium, while a significant increase is observed with non-fermentable carbon sources. However, the molecular basis of this phenomenon has not been established. Results In this work, we showed that glucose caused transcriptional repression of the three genes involved in the synthesis of astaxanthin from geranylgeranyl pyrophosphate in X. dendrorhous, which correlates with a complete inhibition of pigment synthesis. Strikingly, this regulatory response was completely altered in mutant strains that are incapable of synthesizing astaxanthin. However, we found that addition of ethanol caused the induction of crtYB and crtS gene expression and promoted de novo synthesis of carotenoids. The induction of carotenogenesis was noticeable as early as 24 h after ethanol addition. Conclusion For the first time, we demonstrated that carbon source-dependent regulation of astaxanthin biosynthesis in X. dendrorhous involves changes at the transcriptional level. Such regulatory mechanism provides an explanation for the strong and early inhibitory effect of glucose on the biosynthesis of this carotenoid.

  4. Engineering of a plasmid-free Escherichia coli strain for improved in vivo biosynthesis of astaxanthin

    Directory of Open Access Journals (Sweden)

    Steuer Kristin

    2011-04-01

    Full Text Available Abstract Background The xanthophyll astaxanthin is a high-value compound with applications in the nutraceutical, cosmetic, food, and animal feed industries. Besides chemical synthesis and extraction from naturally producing organisms like Haematococcus pluvialis, heterologous biosynthesis in non-carotenogenic microorganisms like Escherichia coli, is a promising alternative for sustainable production of natural astaxanthin. Recent achievements in the metabolic engineering of E. coli strains have led to a significant increase in the productivity of carotenoids like lycopene or β-carotene by increasing the metabolic flux towards the isoprenoid precursors. For the heterologous biosynthesis of astaxanthin in E. coli, however, the conversion of β-carotene to astaxanthin is obviously the most critical step towards an efficient biosynthesis of astaxanthin. Results Here we report the construction of the first plasmid-free E. coli strain that produces astaxanthin as the sole carotenoid compound with a yield of 1.4 mg/g cdw (E. coli BW-ASTA. This engineered E. coli strain harbors xanthophyll biosynthetic genes from Pantoea ananatis and Nostoc punctiforme as individual expression cassettes on the chromosome and is based on a β-carotene-producing strain (E. coli BW-CARO recently developed in our lab. E. coli BW-CARO has an enhanced biosynthesis of the isoprenoid precursor isopentenyl diphosphate (IPP and produces β-carotene in a concentration of 6.2 mg/g cdw. The expression of crtEBIY along with the β-carotene-ketolase gene crtW148 (NpF4798 and the β-carotene-hydroxylase gene (crtZ under controlled expression conditions in E. coli BW-ASTA directed the pathway exclusively towards the desired product astaxanthin (1.4 mg/g cdw. Conclusions By using the λ-Red recombineering technique, genes encoding for the astaxanthin biosynthesis pathway were stably integrated into the chromosome of E. coli. The expression levels of chromosomal integrated recombinant

  5. Astaxanthin reduces isoflurane-induced neuroapoptosis via the PI3K/Akt pathway.

    Science.gov (United States)

    Wang, Chun-Mei; Cai, Xiao-Lan; Wen, Qing-Ping

    2016-05-01

    Astaxanthin is an oxygen-containing derivative of carotenoids that effectively suppresses reactive oxygen and has nutritional and medicinal value. The mechanisms underlying the effects of astaxanthin on isoflurane‑induced neuroapoptosis remain to be fully understood. The present study was conducted to evaluate the protective effect of astaxanthin to reduce isoflurane‑induced neuroapoptosis and to investigate the underlying mechanisms. The results demonstrated that isoflurane induced brain damage, increased caspase‑3 activity and suppressed the phosphatidylinositol 3‑kinase (PI3K)/protein kinase B (Akt) signaling pathway in an in vivo model. However, treatment with astaxanthin significantly inhibited brain damage, suppressed caspase‑3 activity and upregulated the PI3K/Akt pathway in the isoflurane‑induced rats. Furthermore, isoflurane suppressed cell growth, induced cell apoptosis, enhanced caspase‑3 activity and downregulated the PI3K/Akt pathway in organotypic hippocampal slice culture. Administration of astaxanthin significantly promoted cell growth, reduced cell apoptosis and caspase‑3 activity, and upregulated the PI3K/Akt pathway and isoflurane‑induced neuroapoptosis. The present study demonstrated that downregulation of the PI3K/Akt pathway reduced the effect of astaxanthin to protect against isoflurane‑induced neuroapoptosis in the in vitro model. The results of the current study suggested that the protective effect of astaxanthin reduces the isoflurane-induced neuroapoptosis via activation of the PI3K/Akt signaling pathway. PMID:27035665

  6. Highly efficient biosynthesis of astaxanthin in Saccharomyces cerevisiae by integration and tuning of algal crtZ and bkt.

    Science.gov (United States)

    Zhou, Pingping; Ye, Lidan; Xie, Wenping; Lv, Xiaomei; Yu, Hongwei

    2015-10-01

    Astaxanthin is a highly valued carotenoid with strong antioxidant activity and has wide applications in aquaculture, food, cosmetic, and pharmaceutical industries. The market demand for natural astaxanthin promotes research in metabolic engineering of heterologous hosts for astaxanthin production. In this study, an astaxanthin-producing Saccharomyces cerevisiae strain was created by successively introducing the Haematococcus pluvialis β-carotenoid hydroxylase (crtZ) and ketolase (bkt) genes into a previously constructed β-carotene hyperproducer. Further integration of strategies including codon optimization, gene copy number adjustment, and iron cofactor supplementation led to significant increase in the astaxanthin production, reaching up to 4.7 mg/g DCW in the shake-flask cultures which is the highest astaxanthin content in S. cerevisiae reported to date. Besides, the substrate specificity of H. pluvialis CrtZ and BKT and the probable formation route of astaxanthin from β-carotene in S. cerevisiae were figured out by expressing the genes separately and in combination. The yeast strains engineered in this work provide a basis for further improving biotechnological production of astaxanthin and might offer a useful general approach to the construction of heterologous biosynthetic pathways for other natural products. PMID:26156241

  7. Biosynthesis of astaxanthin in the green alga Pleurastrum sarcinoideum

    Czech Academy of Sciences Publication Activity Database

    Kopecký, Jiří; Lukavská, Alena; Verbovikova, Lena; Sergejevova, Magda

    Roquetas de Nar, 2002, s. 58. [Congress of the International Society for Applied Phycology /1./. Roquetas de Mar (ES), 26.05.2002-30.05.2002] R&D Projects: GA MŠk LN00A141 Institutional research plan: CEZ:AV0Z5020903 Keywords : hplc * biosynthesis Subject RIV: EC - Immunology

  8. Genome mining of astaxanthin biosynthetic genes from Sphingomonas sp. ATCC 55669 for heterologous overproduction in Escherichia coli.

    Science.gov (United States)

    Ma, Tian; Zhou, Yuanjie; Li, Xiaowei; Zhu, Fayin; Cheng, Yongbo; Liu, Yi; Deng, Zixin; Liu, Tiangang

    2016-02-01

    As a highly valued keto-carotenoid, astaxanthin is widely used in nutritional supplements and pharmaceuticals. Therefore, the demand for biosynthetic astaxanthin and improved efficiency of astaxanthin biosynthesis has driven the investigation of metabolic engineering of native astaxanthin producers and heterologous hosts. However, microbial resources for astaxanthin are limited. In this study, we found that the α-Proteobacterium Sphingomonas sp. ATCC 55669 could produce astaxanthin naturally. We used whole-genome sequencing to identify the astaxanthin biosynthetic pathway using a combined PacBio-Illumina approach. The putative astaxanthin biosynthetic pathway in Sphingomonas sp. ATCC 55669 was predicted. For further confirmation, a high-efficiency targeted engineering carotenoid synthesis platform was constructed in E. coli for identifying the functional roles of candidate genes. All genes involved in astaxanthin biosynthesis showed discrete distributions on the chromosome. Moreover, the overexpression of exogenous E. coli idi in Sphingomonas sp. ATCC 55669 increased astaxanthin production by 5.4-fold. This study described a new astaxanthin producer and provided more biosynthesis components for bioengineering of astaxanthin in the future. PMID:26580858

  9. Metabolic engineering of the astaxanthin-biosynthetic pathway of Xanthophyllomyces dendrorhous

    NARCIS (Netherlands)

    Visser, H.; Ooyen, van A.J.J.; Verdoes, J.C.

    2003-01-01

    This review describes the different approaches that have been used to manipulate and improve carotenoid production in Xanthophyllomyces dendrorhous. The red yeast X dendrorhous (formerly known as Phaffia rhodozyma) is one of the microbiological production systems for natural astaxanthin. Astaxanthin

  10. Astaxanthin Inhibits Acetaldehyde-Induced Cytotoxicity in SH-SY5Y Cells by Modulating Akt/CREB and p38MAPK/ERK Signaling Pathways.

    Science.gov (United States)

    Yan, Tingting; Zhao, Yan; Zhang, Xia; Lin, Xiaotong

    2016-03-01

    Excessive alcohol consumption can lead to brain tissue damage and cognitive dysfunction. Acetaldehyde, the most toxic metabolite of ethanol, mediates the brain tissue damage and cognitive dysfunction induced by chronic excessive alcohol consumption. In this study, the effect of astaxanthin, a marine bioactive compound, on acetaldehyde-induced cytotoxicity was investigated in SH-SY5Y cells. It was found that astaxanthin protected cells from apoptosis by ameliorating the effect of acetaldehyde on the expression of Bcl-2 family proteins, preventing the reduction of anti-apoptotic protein Bcl-2 and the increase of pro-apoptotic protein Bak induced by acetaldehyde. Further analyses showed that astaxanthin treatment inhibited acetaldehyde-induced reduction of the levels of activated Akt and cyclic AMP-responsive element binding protein (CREB). Astaxanthin treatment also prevented acetaldehyde-induced increase of the level of activated p38 mitogen-activated protein kinase (MAPK) and decrease of the level of activated extracellular signal-regulated kinases (ERKs). Activation of Akt/CREB pathway promotes cell survival and is involved in the upregulation of Bcl-2 gene. P38MAPK plays a critical role in apoptotic events while ERKs mediates the inhibition of apoptosis. Thus, astaxanthin may inhibit acetaldehyde-induced apoptosis through promoting the activation of Akt/CREB and ERKs and blocking the activation of p38MAPK. In addition, astaxanthin treatment suppressed the oxidative stress induced by acetaldehyde and restored the antioxidative capacity of SH-SY5Y cells. Therefore, astaxanthin may protect cells against acetaldehyde-induced cytotoxicity through maintaining redox balance and modulating apoptotic and survival signals. The results suggest that astaxanthin treatment may be beneficial for preventing neurotoxicity associated with acetaldehyde and excessive alcohol consumption. PMID:26978376

  11. Astaxanthin Inhibits Acetaldehyde-Induced Cytotoxicity in SH-SY5Y Cells by Modulating Akt/CREB and p38MAPK/ERK Signaling Pathways

    Directory of Open Access Journals (Sweden)

    Tingting Yan

    2016-03-01

    Full Text Available Excessive alcohol consumption can lead to brain tissue damage and cognitive dysfunction. Acetaldehyde, the most toxic metabolite of ethanol, mediates the brain tissue damage and cognitive dysfunction induced by chronic excessive alcohol consumption. In this study, the effect of astaxanthin, a marine bioactive compound, on acetaldehyde-induced cytotoxicity was investigated in SH-SY5Y cells. It was found that astaxanthin protected cells from apoptosis by ameliorating the effect of acetaldehyde on the expression of Bcl-2 family proteins, preventing the reduction of anti-apoptotic protein Bcl-2 and the increase of pro-apoptotic protein Bak induced by acetaldehyde. Further analyses showed that astaxanthin treatment inhibited acetaldehyde-induced reduction of the levels of activated Akt and cyclic AMP-responsive element binding protein (CREB. Astaxanthin treatment also prevented acetaldehyde-induced increase of the level of activated p38 mitogen-activated protein kinase (MAPK and decrease of the level of activated extracellular signal-regulated kinases (ERKs. Activation of Akt/CREB pathway promotes cell survival and is involved in the upregulation of Bcl-2 gene. P38MAPK plays a critical role in apoptotic events while ERKs mediates the inhibition of apoptosis. Thus, astaxanthin may inhibit acetaldehyde-induced apoptosis through promoting the activation of Akt/CREB and ERKs and blocking the activation of p38MAPK. In addition, astaxanthin treatment suppressed the oxidative stress induced by acetaldehyde and restored the antioxidative capacity of SH-SY5Y cells. Therefore, astaxanthin may protect cells against acetaldehyde-induced cytotoxicity through maintaining redox balance and modulating apoptotic and survival signals. The results suggest that astaxanthin treatment may be beneficial for preventing neurotoxicity associated with acetaldehyde and excessive alcohol consumption.

  12. Cloning of the cytochrome p450 reductase (crtR) gene and its involvement in the astaxanthin biosynthesis of Xanthophyllomyces dendrorhous

    OpenAIRE

    Sepúlveda Dionisia; Niklitschek Mauricio; Marcoleta Andrés; Lozano Carla; Carmona Marisela; Barahona Salvador; Alcaíno Jennifer; Baeza Marcelo; Cifuentes Víctor

    2008-01-01

    Abstract Background The yeast Xanthophyllomyces dendrorhous synthesizes astaxanthin, a carotenoid with high commercial interest. The proposed biosynthetic route in this organism is isopentenyl-pyrophosphate (IPP) → geranyleranyl pyrophosphate (GGPP) → phytoene → lycopene → β-carotene → astaxanthin. Recently, it has been published that the conversion of β-carotene into astaxanthin requires only one enzyme, astaxanthin synthase or CrtS, encoded by crtS gene. This enzyme belongs to the cytochrom...

  13. Overexpression of a bifunctional enzyme, CrtS, enhances astaxanthin synthesis through two pathways in Phaffia rhodozyma

    OpenAIRE

    Chi, Shuang; He, Yanfeng; Ren, Jie; Su, Qian; Liu, Xingchao; Chen, Zhi; Wang, Mingan; Ying LI; Li, Jilun

    2015-01-01

    Background A moderate-temperature, astaxanthin-overproducing mutant strain (termed MK19) of Phaffia rhodozyma was generated in our laboratory. The intracellular astaxanthin content of MK19 was 17-fold higher than that of wild-type. The TLC profile of MK19 showed a band for an unknown carotenoid pigment between those of β-carotene and astaxanthin. In the present study, we attempted to identify the unknown pigment and to enhance astaxanthin synthesis in MK19 by overexpression of the crtS gene t...

  14. Agricultural biochemistry: reaction mechanisms and pathways in biosynthesis

    International Nuclear Information System (INIS)

    Plant tracer studies in research concerning human food chains are reviewed in the following sections: tracer studies with 14C (photosynthesis and other biosynthesis pathways in plants, intermediary carbon pathways), tracer studies with 13C (13C NMR spectrometry and its applications in biosynthesis pathways), the fate of hydrogen, deuterium as a tracer, triton magnetic resonance spectrometry, double label isotope ratios (reaction mechanism studies and studies of precursor-product relationships), kinetic isotope effects, 18O and organic mass spectrometry, 18O and 31P NMR, precursor-product incorporation and dilution. (U.K.)

  15. Biosynthesis and metabolic pathways of pivalic acid

    Czech Academy of Sciences Publication Activity Database

    Řezanka, Tomáš; Kolouchová, I.; Čejková, A.; Sigler, Karel

    2012-01-01

    Roč. 95, č. 6 (2012), s. 1371-1376. ISSN 0175-7598 R&D Projects: GA ČR(CZ) GAP503/11/0215 Institutional support: RVO:61388971 Keywords : Pivalic acid * Isooctane * Biosynthesis Subject RIV: EE - Microbiology, Virology Impact factor: 3.689, year: 2012

  16. Two pathways for cysteine biosynthesis in Leishmania major

    OpenAIRE

    Williams, Roderick A. M.; Westrop, Gareth D.; Coombs, Graham H.

    2009-01-01

    Abstract Genome mining and biochemical analyses have shown that L. major possesses two pathways for cysteine synthesis - the de novo biosynthesis pathway comprising serine acetyltransferase (SAT) and cysteine synthase (CS) and the reverse transsulfuration (RTS) pathway comprising cystathionine ?-synthase (CBS) and cystathionine gamma-lyase (CGL). The L. major CS (LmjCS) is similar to the type A CSs of bacteria and catalyses the synthesis of cysteine using O-acetyserine and sulfide...

  17. Inhibitors targeting on cell wall biosynthesis pathway of MRSA.

    Science.gov (United States)

    Hao, Haihong; Cheng, Guyue; Dai, Menghong; Wu, Qinghua; Yuan, Zonghui

    2012-11-01

    Methicillin resistant Staphylococcus aureus (MRSA), widely known as a type of new superbug, has aroused world-wide concern. Cell wall biosynthesis pathway is an old but good target for the development of antibacterial agents. Peptidoglycan and wall teichoic acids (WTAs) biosynthesis are two main processes of the cell wall biosynthesis pathway (CWBP). Other than penicillin-binding proteins (PBPs), some key factors (Mur enzymes, lipid I or II precursor, etc.) in CWBP are becoming attractive molecule targets for the discovery of anti-MRSA compounds. A number of new compounds, with higher affinity for PBPs or with inhibitory activity on such molecule targets in CWBP of MRSA, have been in the pipeline recently. This review concludes recent research achievements and provides a complete picture of CWBP of MRSA, including the peptidoglycan and wall teichoic acids synthesis pathway. The potential inhibitors targeting on CWBP are subsequently presented to improve development of novel therapeutic strategies for MRSA. PMID:22898792

  18. Cloning of the cytochrome p450 reductase (crtR gene and its involvement in the astaxanthin biosynthesis of Xanthophyllomyces dendrorhous

    Directory of Open Access Journals (Sweden)

    Sepúlveda Dionisia

    2008-10-01

    Full Text Available Abstract Background The yeast Xanthophyllomyces dendrorhous synthesizes astaxanthin, a carotenoid with high commercial interest. The proposed biosynthetic route in this organism is isopentenyl-pyrophosphate (IPP → geranyleranyl pyrophosphate (GGPP → phytoene → lycopene → β-carotene → astaxanthin. Recently, it has been published that the conversion of β-carotene into astaxanthin requires only one enzyme, astaxanthin synthase or CrtS, encoded by crtS gene. This enzyme belongs to the cytochrome P450 protein family. Results In this work, a crtR gene was isolated from X. dendrorhous yeast, which encodes a cytochrome P450 reductase (CPR that provides CrtS with the necessary electrons for substrate oxygenation. We determined the structural organization of the crtR gene and its location in the yeast electrophoretic karyotype. Two transformants, CBSTr and T13, were obtained by deleting the crtR gene and inserting a hygromycin B resistance cassette. The carotenoid composition of the transformants was altered in relation to the wild type strain. CBSTr forms yellow colonies because it is unable to produce astaxanthin, hence accumulating β-carotene. T13 forms pale colonies because its astaxanthin content is reduced and its β-carotene content is increased. Conclusion In addition to the crtS gene, X. dendrorhous requires a novel gene, crtR, for the conversion of β-carotene to astaxanthin.

  19. Auxin Biosynthesis: Are the Indole-3-Acetic Acid and Phenylacetic Acid Biosynthesis Pathways Mirror Images?

    Science.gov (United States)

    Cook, Sam D; Nichols, David S; Smith, Jason; Chourey, Prem S; McAdam, Erin L; Quittenden, Laura; Ross, John J

    2016-06-01

    The biosynthesis of the main auxin in plants (indole-3-acetic acid [IAA]) has been elucidated recently and is thought to involve the sequential conversion of Trp to indole-3-pyruvic acid to IAA However, the pathway leading to a less well studied auxin, phenylacetic acid (PAA), remains unclear. Here, we present evidence from metabolism experiments that PAA is synthesized from the amino acid Phe, via phenylpyruvate. In pea (Pisum sativum), the reverse reaction, phenylpyruvate to Phe, is also demonstrated. However, despite similarities between the pathways leading to IAA and PAA, evidence from mutants in pea and maize (Zea mays) indicate that IAA biosynthetic enzymes are not the main enzymes for PAA biosynthesis. Instead, we identified a putative aromatic aminotransferase (PsArAT) from pea that may function in the PAA synthesis pathway. PMID:27208245

  20. Astaxanthin Suppresses MPP+-Induced Oxidative Damage in PC12 Cells through a Sp1/NR1 Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Xiaochun Chen

    2013-03-01

    Full Text Available Objective: To investigate astaxanthin (ATX neuroprotection, and its mechanism, on a 1-methyl-4-phenyl-pyridine ion (MPP+-induced cell model of Parkinson’s disease. Methods: Mature, differentiated PC12 cells treated with MPP+ were used as an in vitro cell model. The MTT assay was used to investigate cell viability after ATX treatment, and western blot analysis was used to observe Sp1 (activated transcription factor 1 and NR1 (NMDA receptor subunit 1 protein expression, real-time PCR was used to monitor Sp1 and NR1 mRNA, and cell immunofluorescence was used to determine the location of Sp1 and NR1 protein and the nuclear translocation of Sp1. Results: PC12 cell viability was significantly reduced by MPP+ treatment. The expression of Sp1 and NR1 mRNA and protein were increased compared with the control (p < 0.01. Following co-treatment with ATX and MPP+, cell viability was significantly increased, and Sp1 and NR1 mRNA and protein were decreased, compared with the MPP+ groups (p < 0.01. In addition, mithracycin A protected PC12 cells from oxidative stress caused by MPP+ by specifically inhibiting the expression of Sp1. Moreover, cell immunofluorescence revealed that ATX could suppress Sp1 nuclear transfer. Conclusion: ATX inhibited oxidative stress induced by MPP+ in PC12 cells, via the SP1/NR1 signaling pathway.

  1. Polyketides in Aspergillus terreus: biosynthesis pathway discovery and application.

    Science.gov (United States)

    Yin, Ying; Cai, Menghao; Zhou, Xiangshan; Li, Zhiyong; Zhang, Yuanxing

    2016-09-01

    The knowledge of biosynthesis gene clusters, production improving methods, and bioactivity mechanisms is very important for the development of filamentous fungi metabolites. Metabolic engineering and heterologous expression methods can be applied to improve desired metabolite production, when their biosynthesis pathways have been revealed. And, stable supplement is a necessary basis of bioactivity mechanism discovery and following clinical trial. Aspergillus terreus is an outstanding producer of many bioactive agents, and a large part of them are polyketides. In this review, we took polyketides from A. terreus as examples, focusing on 13 polyketide synthase (PKS) genes in A. terreus NIH 2624 genome. The biosynthesis pathways of nine PKS genes have been reported, and their downstream metabolites are lovastatin, terreic acid, terrein, geodin, terretonin, citreoviridin, and asperfuranone, respectively. Among them, lovastatin is a well-known hypolipidemic agent. Terreic acid, terrein, citreoviridin, and asperfuranone show good bioactivities, especially anticancer activities. On the other hand, geodin and terretonin are mycotoxins. So, biosynthesis gene cluster information is important for the production or elimination of them. We also predicted three possible gene clusters that contain four PKS genes by homologous gene alignment with other Aspergillus strains. We think that this is an effective way to mine secondary metabolic gene clusters. PMID:27455860

  2. A mitochondrial pathway for biosynthesis of lipid mediators

    Science.gov (United States)

    Tyurina, Yulia Y.; Poloyac, Samuel M.; Tyurin, Vladimir A.; Kapralov, Alexander A.; Jiang, Jianfei; Anthonymuthu, Tamil Selvan; Kapralova, Valentina I.; Vikulina, Anna S.; Jung, Mi-Yeon; Epperly, Michael W.; Mohammadyani, Dariush; Klein-Seetharaman, Judith; Jackson, Travis C.; Kochanek, Patrick M.; Pitt, Bruce R.; Greenberger, Joel S.; Vladimirov, Yury A.; Bayır, Hülya; Kagan, Valerian E.

    2014-06-01

    The central role of mitochondria in metabolic pathways and in cell-death mechanisms requires sophisticated signalling systems. Essential in this signalling process is an array of lipid mediators derived from polyunsaturated fatty acids. However, the molecular machinery for the production of oxygenated polyunsaturated fatty acids is localized in the cytosol and their biosynthesis has not been identified in mitochondria. Here we report that a range of diversified polyunsaturated molecular species derived from a mitochondria-specific phospholipid, cardiolipin (CL), is oxidized by the intermembrane-space haemoprotein, cytochrome c. We show that a number of oxygenated CL species undergo phospholipase A2-catalysed hydrolysis and thus generate multiple oxygenated fatty acids, including well-known lipid mediators. This represents a new biosynthetic pathway for lipid mediators. We demonstrate that this pathway, which includes the oxidation of polyunsaturated CLs and accumulation of their hydrolysis products (oxygenated linoleic, arachidonic acids and monolysocardiolipins), is activated in vivo after acute tissue injury.

  3. The essential role of the phosphorylated pathway of serine biosynthesis in Arabidopsis

    OpenAIRE

    Muñoz-Bertomeu, Jesús; Anoman, Armand Djoro; Flores-Tornero, María; Toujani, Walid; Rosa-Téllez, Sara; Fernie, Alisdair R.; Roje, Sanja; Segura, Juan; Ros, Roc

    2013-01-01

    In plants, 3 different pathways of serine biosynthesis have been described: the Glycolate pathway, which is associated with photorespiration, and 2 non-photorespiratory pathways, the Glycerate and the Phosphorylated pathways. The Phosphorylated Pathway of Serine Biosynthesis (PPSB) has been known since the 1950s, but has been studied relatively little, probably because it was considered of minor significance as compared with the Glycolate pathway. In the associated study1, we described for th...

  4. Regulatory Cross-Talks and Cascades in Rice Hormone Biosynthesis Pathways Contribute to Stress Signaling.

    Science.gov (United States)

    Deb, Arindam; Grewal, Rumdeep K; Kundu, Sudip

    2016-01-01

    Crosstalk among different hormone signaling pathways play an important role in modulating plant response to both biotic and abiotic stress. Hormone activity is controlled by its bio-availability, which is again influenced by its biosynthesis. Thus, independent hormone biosynthesis pathways must be regulated and co-ordinated to mount an integrated response. One of the possibilities is to use cis-regulatory elements to orchestrate expression of hormone biosynthesis genes. Analysis of CREs, associated with differentially expressed hormone biosynthesis related genes in rice leaf under Magnaporthe oryzae attack and drought stress enabled us to obtain insights about cross-talk among hormone biosynthesis pathways at the transcriptional level. We identified some master transcription regulators that co-ordinate different hormone biosynthesis pathways under stress. We found that Abscisic acid and Brassinosteroid regulate Cytokinin conjugation; conversely Brassinosteroid biosynthesis is affected by both Abscisic acid and Cytokinin. Jasmonic acid and Ethylene biosynthesis may be modulated by Abscisic acid through DREB transcription factors. Jasmonic acid or Salicylic acid biosynthesis pathways are co-regulated but they are unlikely to influence each others production directly. Thus, multiple hormones may modulate hormone biosynthesis pathways through a complex regulatory network, where biosynthesis of one hormone is affected by several other contributing hormones. PMID:27617021

  5. Localization of heme biosynthesis pathway enzymes in Plasmodium falciparum.

    Science.gov (United States)

    Rao, Aditya; Yeleswarapu, Sri Jyothsna; Srinivasan, Rajgopal; Bulusu, Gopalakrishnan

    2008-12-01

    Protein trafficking in the malarial parasite Plasmodium falciparum is dictated by a complex life-cycle that involves a variety of intra-cellular and host cell destinations, such as the mitochondrion, apicoplast, rhoptries and micronemes. Of these, the apicoplast and mitochondrion are believed to account for more than 10% of this traffic. Studies have shown that mechanisms for mitochondrion and apicoplast targeting are distinct, despite their close physical proximity. The heme biosynthesis pathway spans both these organelles, making trafficking studies crucial for the spatial demarcation of the constituent interactions. This minireview highlights the challenges in identifying the possible sub-cellular destinations of the heme pathway enzymes using gleanings from literature survey as well as focussed bioinformatic analysis. PMID:19239121

  6. ASTAXANTHIN: A POTENTIAL CAROTENOID

    OpenAIRE

    Jyotika Dhankhar et al.

    2012-01-01

    Astaxanthin, a member of the carotenoid family, is a dark-red pigment which is the main carotenoid found in the marine world of algae and aquatic animals. Astaxanthin, is present in many types of seafood, including salmon, trout, red sea bream, shrimp and lobster, as well as in birds such as flamingo and quail. Synthetic Astaxanthin dominates the world market but recent interest in natural sources of the pigment has increased substantially. Common sources of natural Astaxanthin, are the gree...

  7. Biosynthesis Pathway Related Production of Medium Chain Length Polyhydroxyalkanoates

    Institute of Scientific and Technical Information of China (English)

    林会兰; 史文慧; 吴琼; 陈金春; 徐军; 陈国强

    2001-01-01

    Pseudomonas flava HBE06 isolated from oil-contaminated soil was found to produce polyesters consisting of medium chain length polyhydroxyalkanoates (mci PHA). The strain mainly synthesized PHA containing 3-hydroxyoctanoate (C8 or HO), 3-hydroxynonanoate (C9 or HN), 3-hydroxydecanoate (C10 or HD), and 3-hydroxyunidecanoate (C11 or HUD) as monomers when grown on various substrates. It was found that the monomer ratio (especially C10/C8 or C11/C9) was related to the PHA biosynthesis pathway. When PHA was synthesized via the de novo fatty acid pathway, the molar ratio of C10/C8 was greater than 2. If PHA was synthesized from β-oxidation of fatty acids, C10/C8 was less than 1. Pseudomonas stutzeri 1317 is another mci PHA synthesizing bacteria whose C10/C8 ratio is also related to the synthesis pathway. When the two synthesis pathways were used together, the C10/C8 ratio could be adjusted according to the ratio of the mixed substrates.

  8. Metabolic engineering of cottonseed oil biosynthesis pathway via RNA interference.

    Science.gov (United States)

    Xu, Zhongping; Li, Jingwen; Guo, Xiaoping; Jin, Shuangxia; Zhang, Xianlong

    2016-01-01

    Cottonseed oil is recognized as an important oil in food industry for its unique characters: low flavor reversion and the high level of antioxidants (VitaminE) as well as unsaturated fatty acid. However, the cottonseed oil content of cultivated cotton (Gossypium hirsutum) is only around 20%. In this study, we modified the accumulation of oils by the down-regulation of phosphoenolpyruvate carboxylase 1 (GhPEPC1) via RNA interference in transgenic cotton plants. The qRT-PCR and enzyme activity assay revealed that the transcription and expression of GhPEPC1 was dramatically down-regulated in transgenic lines. Consequently, the cottonseed oil content in several transgenic lines showed a significant (P information for cottonseed oil biosynthesis pathway and shows the potential of creating high cottonseed oil germplasm by RNAi strategy for cotton breeding. PMID:27620452

  9. Astaxanthin Suppresses MPP+-Induced Oxidative Damage in PC12 Cells through a Sp1/NR1 Signaling Pathway

    OpenAIRE

    Xiaochun Chen; Yuangui Zhu; Bixia Huang; Xiaodong Zhang; Qinyong Ye

    2013-01-01

    Objective: To investigate astaxanthin (ATX) neuroprotection, and its mechanism, on a 1-methyl-4-phenyl-pyridine ion (MPP+)-induced cell model of Parkinson’s disease. Methods: Mature, differentiated PC12 cells treated with MPP+ were used as an in vitro cell model. The MTT assay was used to investigate cell viability after ATX treatment, and western blot analysis was used to observe Sp1 (activated transcription factor 1) and NR1 (NMDA receptor subunit 1) protein expression, real-time PCR was us...

  10. Metabolic Engineering of Saccharomyces cerevisiae for Astaxanthin Production and Oxidative Stress Tolerance▿

    OpenAIRE

    Ukibe, Ken; Hashida, Keisuke; Yoshida, Nobuyuki; Takagi, Hiroshi

    2009-01-01

    The red carotenoid astaxanthin possesses higher antioxidant activity than other carotenoids and has great commercial potential for use in the aquaculture, pharmaceutical, and food industries. In this study, we produced astaxanthin in the budding yeast Saccharomyces cerevisiae by introducing the genes involved in astaxanthin biosynthesis of carotenogenic microorganisms. In particular, expression of genes of the red yeast Xanthophyllomyces dendrorhous encoding phytoene desaturase (crtI product)...

  11. Sterol Biosynthesis Pathway as Target for Anti-trypanosomatid Drugs

    Directory of Open Access Journals (Sweden)

    Wanderley de Souza

    2009-01-01

    Full Text Available Sterols are constituents of the cellular membranes that are essential for their normal structure and function. In mammalian cells, cholesterol is the main sterol found in the various membranes. However, other sterols predominate in eukaryotic microorganisms such as fungi and protozoa. It is now well established that an important metabolic pathway in fungi and in members of the Trypanosomatidae family is one that produces a special class of sterols, including ergosterol, and other 24-methyl sterols, which are required for parasitic growth and viability, but are absent from mammalian host cells. Currently, there are several drugs that interfere with sterol biosynthesis (SB that are in use to treat diseases such as high cholesterol in humans and fungal infections. In this review, we analyze the effects of drugs such as (a statins, which act on the mevalonate pathway by inhibiting HMG-CoA reductase, (b bisphosphonates, which interfere with the isoprenoid pathway in the step catalyzed by farnesyl diphosphate synthase, (c zaragozic acids and quinuclidines, inhibitors of squalene synthase (SQS, which catalyzes the first committed step in sterol biosynthesis, (d allylamines, inhibitors of squalene epoxidase, (e azoles, which inhibit C14α-demethylase, and (f azasterols, which inhibit Δ24(25-sterol methyltransferase (SMT. Inhibition of this last step appears to have high selectivity for fungi and trypanosomatids, since this enzyme is not found in mammalian cells. We review here the IC50 values of these various inhibitors, their effects on the growth of trypanosomatids (both in axenic cultures and in cell cultures, and their effects on protozoan structural organization (as evaluted by light and electron microscopy and lipid composition. The results show that the mitochondrial membrane as well as the membrane lining the protozoan cell body and flagellum are the main targets. Probably as a consequence of these primary effects, other important changes take

  12. LOCALIZATION OF THE PATHWAY OF THE PENICILLIN BIOSYNTHESIS IN PENICILLIUM-CHRYSOGENUM

    NARCIS (Netherlands)

    MULLER, WH; VANDERKRIFT, TP; KROUWER, AJJ; WOSTEN, HAB; VANDERVOORT, LHM; SMAAL, EB; VERKLEIJ, AJ

    1991-01-01

    The localization of the enzymes involved in penicillin biosynthesis in Penicillium chrysogenum hyphae has been studied by immunological detection methods in combination with electron microscopy and cell fractionation. The results suggest a complicated pathway involving different intracellular locati

  13. Auxin Biosynthesis: Are the Indole-3-Acetic Acid and Phenylacetic Acid Biosynthesis Pathways Mirror Images?1[OPEN

    Science.gov (United States)

    Nichols, David S.; Smith, Jason; Chourey, Prem S.; McAdam, Erin L.; Quittenden, Laura

    2016-01-01

    The biosynthesis of the main auxin in plants (indole-3-acetic acid [IAA]) has been elucidated recently and is thought to involve the sequential conversion of Trp to indole-3-pyruvic acid to IAA. However, the pathway leading to a less well studied auxin, phenylacetic acid (PAA), remains unclear. Here, we present evidence from metabolism experiments that PAA is synthesized from the amino acid Phe, via phenylpyruvate. In pea (Pisum sativum), the reverse reaction, phenylpyruvate to Phe, is also demonstrated. However, despite similarities between the pathways leading to IAA and PAA, evidence from mutants in pea and maize (Zea mays) indicate that IAA biosynthetic enzymes are not the main enzymes for PAA biosynthesis. Instead, we identified a putative aromatic aminotransferase (PsArAT) from pea that may function in the PAA synthesis pathway. PMID:27208245

  14. Simulation of a Petri net-based Model of the Terpenoid Biosynthesis Pathway

    OpenAIRE

    Hawari Aliah; Mohamed-Hussein Zeti-Azura

    2010-01-01

    Abstract Background The development and simulation of dynamic models of terpenoid biosynthesis has yielded a systems perspective that provides new insights into how the structure of this biochemical pathway affects compound synthesis. These insights may eventually help identify reactions that could be experimentally manipulated to amplify terpenoid production. In this study, a dynamic model of the terpenoid biosynthesis pathway was constructed based on the Hybrid Functional Petri Net (HFPN) t...

  15. An overview of the non-mevalonate pathway for terpenoid biosynthesis in plants

    Indian Academy of Sciences (India)

    Vinod Shanker Dubey; Ritu Bhalla; Rajesh Luthra

    2003-09-01

    Terpenoids are known to have many important biological and physiological functions. Some of them are also known for their pharmaceutical significance. In the late nineties after the discovery of a novel non-mevalonate (non-MVA) pathway, the whole concept of terpenoid biosynthesis has changed. In higher plants, the conventional acetate-mevalonate (Ac-MVA) pathway operates mainly in the cytoplasm and mitochondria and synthesizes sterols, sesquiterpenes and ubiquinones predominantly. The plastidic non-MVA pathway however synthesizes hemi-, mono-, sesqui- and di-terpenes, along with carotenoids and phytol chain of chlorophyll. In this paper, recent developments on terpenoids biosynthesis are reviewed with respect to the non-MVA pathway.

  16. Advances in the Plant Isoprenoid Biosynthesis Pathway and Its Metabolic Engineering

    Institute of Scientific and Technical Information of China (English)

    Yan LIU; Hong WANG; He-Chun YE; Guo-Feng LI

    2005-01-01

    Although the cytosolic isoprenoid biosynthetic pathway, mavolonate pathway, in plants has been known for many years, a new plastidial 1-deoxyxylulose-5-phosphate (DXP) pathway was identified in the past few years and its related intermediates, enzymes, and genes have been characterized quite recently.With a deep insight into the biosynthetic pathway of isoprenoids, investigations into the metabolic engineering of isoprenoid biosynthesis have started to prosper. In the present article, recent advances in the discoveries and regulatory roles of new genes and enzymes in the plastidial isoprenoid biosynthesis path way are reviewed and examples of the metabolic engineering of cytosolic and plastidial isoprenoids biosnthesis are discussed.

  17. A Streamlined Metabolic Pathway For the Biosynthesis of Moenomycin A

    OpenAIRE

    Ostash, Bohdan; Saghatelian, Alan; Walker, Suzanne

    2007-01-01

    Moenomycin A (MmA) is a member of the phosphoglycolipid family of antibiotics, which are the only natural products known to target directly the extracellular transglycosylases involved in peptidoglycan biosynthesis. The structural and biological uniqueness of MmA make it an attractive starting point for the development of new antibacterial drugs. In order both to elucidate the biosynthesis of this unusual compound, and to develop tools to manipulate its structure, we have identified the MmA b...

  18. A chloroplast pathway for the de novo biosynthesis of triacylglycerol in Chlamydomonas reinhardtii

    Energy Technology Data Exchange (ETDEWEB)

    Fan, J.; Xu, C.; Andre, C.

    2011-06-23

    Neutral lipid metabolism has been extensively studied in yeast, plants and mammals. In contrast, little information is available regarding the biochemical pathway, enzymes and regulatory factors involved in the biosynthesis of triacylglycerol (TAG) in microalgae. In the conventional TAG biosynthetic pathway widely accepted for yeast, plants and mammals, TAG is assembled in the endoplasmic reticulum (ER) from its immediate precursor diacylglycerol (DAG) made by ER-specific acyltransferases, and is deposited exclusively in lipid droplets in the cytosol. Here, we demonstrated that the unicellular microalga Chlamydomonas reinhardtii employs a distinct pathway that uses DAG derived almost exclusively from the chloroplast to produce TAG. This unique TAG biosynthesis pathway is largely dependent on de novo fatty acid synthesis, and the TAG formed in this pathway is stored in lipid droplets in both the chloroplast and the cytosol. These findings have wide implications for understanding TAG biosynthesis and storage and other areas of lipid metabolism in microalgae and other organisms.

  19. Astaxanthin Inhibits Acetaldehyde-Induced Cytotoxicity in SH-SY5Y Cells by Modulating Akt/CREB and p38MAPK/ERK Signaling Pathways

    OpenAIRE

    Tingting Yan; Yan Zhao; Xia Zhang; Xiaotong Lin

    2016-01-01

    Excessive alcohol consumption can lead to brain tissue damage and cognitive dysfunction. Acetaldehyde, the most toxic metabolite of ethanol, mediates the brain tissue damage and cognitive dysfunction induced by chronic excessive alcohol consumption. In this study, the effect of astaxanthin, a marine bioactive compound, on acetaldehyde-induced cytotoxicity was investigated in SH-SY5Y cells. It was found that astaxanthin protected cells from apoptosis by ameliorating the effect of acetaldehyde ...

  20. Identification and functional characterization of the CYP51 gene from the yeast Xanthophyllomyces dendrorhous that is involved in ergosterol biosynthesis

    OpenAIRE

    Leiva, Kritsye; Werner, Nicole; Sepúlveda, Dionisia; Barahona, Salvador; Baeza, Marcelo; Cifuentes, Víctor; Alcaíno, Jennifer

    2015-01-01

    Background Xanthophyllomyces dendrorhous is a basidiomycetous yeast that synthesizes astaxanthin, a carotenoid with great biotechnological impact. The ergosterol and carotenoid synthetic pathways derive from the mevalonate pathway and involve cytochrome P450 enzymes. Among these enzymes, the CYP51 family, which is involved in ergosterol biosynthesis, is one of the most remarkable that has C14-demethylase activity. Results In this study, the CYP51 gene from X. dendrorhous was isolated and its ...

  1. ASTAXANTHIN: A POTENTIAL CAROTENOID

    Directory of Open Access Journals (Sweden)

    Jyotika Dhankhar et al.

    2012-05-01

    Full Text Available Astaxanthin, a member of the carotenoid family, is a dark-red pigment which is the main carotenoid found in the marine world of algae and aquatic animals. Astaxanthin, is present in many types of seafood, including salmon, trout, red sea bream, shrimp and lobster, as well as in birds such as flamingo and quail. Synthetic Astaxanthin dominates the world market but recent interest in natural sources of the pigment has increased substantially. Common sources of natural Astaxanthin, are the green algae haematococcus pluvialis, the red yeast, Phaffia rhodozyma, as well as crustacean byproducts. Astaxanthin possesses unusual antioxidant property which has caused a surge in the nutraceutical market of the encapsulated products. Numerous studies have shown that astaxanthin has potential health-promoting effects in the prevention and treatment of various diseases, such as cancers, chronic inflammatory diseases, metabolic syndrome, diabetes, diabetic nephropathy, cardiovascular diseases, gastrointestinal diseases, liver diseases, neurodegenerative diseases, eye diseases, skin diseases, exercise-induced fatigue, male infertility, and renal failure. In this article, the currently available scientific literature regarding the most significant activities of astaxanthin is reviewed.

  2. Effects of modulation of pentose-phosphate pathway on biosynthesis of ansamitocins in Actinosynnema pretiosum.

    Science.gov (United States)

    Fan, Yuxiang; Hu, Fengxian; Wei, Liujing; Bai, Linquan; Hua, Qiang

    2016-07-20

    Ansamitocins, produced by Actinosynnema pretiosum, are a group of maytansinoid antibiotics that block the assembly of tubulin into functional microtubules. The precursors of ansamitocin biosynthesis are generally derived from the Embden-Meyerhof-Parnas (EMP) pathway and the tricarboxylic acid cycle. In this study, central carbon flux distributions were analyzed by (13)C-based flux analysis to reveal the contribution of individual central carbon metabolism pathways. To direct more carbon flux into ansamitocin biosynthesis, pentose phosphate (PP) pathway only and the combination of PP pathway and Entner-Doudoroff (ED) pathway were weakened, respectively. Ansamitocin P-3 (AP-3) productions by both kinds of pathways weakened mutant strains were significantly enhanced in chemically defined medium. In order to draw metabolic flux to the biosynthesis of ansamitocins more efficiently, heterologous phosphoglucomutase was subsequently overexpressed based on a mutant strain with combinational regulation of PP pathway and ED pathway. More fluxes were successfully directed into the UDP-glucose synthetic pathway and the AP-3 production was further improved in this case, reaching approximately 185mg/L in fermentation medium. It was demonstrated that eliminating the bypass pathways and favoring the precursor synthetic pathway could effectively improve ansamitocin production by A. pretiosum, suggesting a promising role of metabolic strategy in improving secondary metabolite production. PMID:27173582

  3. Insight into the haem d1 biosynthesis pathway in heliobacteria through bioinformatics analysis

    OpenAIRE

    Xiong, Jin; Bauer, Carl E.; Pancholy, Anjly

    2007-01-01

    Haem d1 is a unique tetrapyrrole molecule that serves as a prosthetic group of cytochrome cd1, which reduces nitrite to nitric oxide during the process of denitrification. Very little information is available regarding the biosynthesis of haem d1. The extreme difficulty in studying the haem d1 biosynthetic pathway can be partly attributed to the lack of a theoretical basis for experimental investigation. We report here a gene cluster encoding enzymes involved in the biosynthesis of haem d1 in...

  4. In vivo kinetic analysis of the penicillin biosynthesis pathway using PAA stimulus response experiments.

    Science.gov (United States)

    Deshmukh, Amit T; Verheijen, Peter J T; Maleki Seifar, Reza; Heijnen, Joseph J; van Gulik, Walter M

    2015-11-01

    In this study we combined experimentation with mathematical modeling to unravel the in vivo kinetic properties of the enzymes and transporters of the penicillin biosynthesis pathway in a high yielding Penicillium chrysogenum strain. The experiment consisted of a step response experiment with the side chain precursor phenyl acetic acid (PAA) in a glucose-limited chemostat. The metabolite data showed that in the absence of PAA all penicillin pathway enzymes were expressed, leading to the production of a significant amount of 6-aminopenicillanic acid (6APA) as end product. After the stepwise perturbation with PAA, the pathway produced PenG within seconds. From the extra- and intracellular metabolite measurements, hypotheses for the secretion mechanisms of penicillin pathway metabolites were derived. A dynamic model of the penicillin biosynthesis pathway was then constructed that included the formation and transport over the cytoplasmic membrane of pathway intermediates, PAA and the product penicillin-G (PenG). The model parameters and changes in the enzyme levels of the penicillin biosynthesis pathway under in vivo conditions were simultaneously estimated using experimental data obtained at three different timescales (seconds, minutes, hours). The model was applied to determine changes in the penicillin pathway enzymes in time, calculate fluxes and analyze the flux control of the pathway. This led to a reassessment of the in vivo behavior of the pathway enzymes and in particular Acyl-CoA:Isopenicillin N Acyltransferase (AT). PMID:26476338

  5. Agrobacterium mediated transient gene silencing (AMTS in Stevia rebaudiana: insights into steviol glycoside biosynthesis pathway.

    Directory of Open Access Journals (Sweden)

    Praveen Guleria

    Full Text Available BACKGROUND: Steviol glycoside biosynthesis pathway has emerged as bifurcation from ent-kaurenoic acid, substrate of methyl erythritol phosphate pathway that also leads to gibberellin biosynthesis. However, the genetic regulation of steviol glycoside biosynthesis has not been studied. So, in present study RNA interference (RNAi based Agrobacterium mediated transient gene silencing (AMTS approach was followed. SrKA13H and three SrUGTs (SrUGT85C2, SrUGT74G1 and SrUGT76G1 genes encoding ent-kaurenoic acid-13 hydroxylase and three UDP glycosyltransferases of steviol glycoside biosynthesis pathway were silenced in Stevia rebaudiana to understand its molecular mechanism and association with gibberellins. METHODOLOGY/PRINCIPAL FINDINGS: RNAi mediated AMTS of SrKA13H and three SrUGTs has significantly reduced the expression of targeted endogenous genes as well as total steviol glycoside accumulation. While gibberellins (GA3 content was significantly enhanced on AMTS of SrUGT85C2 and SrKA13H. Silencing of SrKA13H and SrUGT85C2 was found to block the metabolite flux of steviol glycoside pathway and shifted it towards GA3 biosynthesis. Further, molecular docking of three SrUGT proteins has documented highest affinity of SrUGT76G1 for the substrates of alternate pathways synthesizing steviol glycosides. This could be a plausible reason for maximum reduction in steviol glycoside content on silencing of SrUGT76G1 than other genes. CONCLUSIONS: SrKA13H and SrUGT85C2 were identified as regulatory genes influencing carbon flux between steviol glycoside and gibberellin biosynthesis. This study has also documented the existence of alternate steviol glycoside biosynthesis route.

  6. Enhancement of astaxanthin production using Haematococcus pluvialis with novel LED wavelength shift strategy.

    Science.gov (United States)

    Xi, Tianqi; Kim, Dae Geun; Roh, Seong Woon; Choi, Jong-Soon; Choi, Yoon-E

    2016-07-01

    Haematococcus pluvialis is a green microalga of particular interest, since it is considered the best potential natural source of astaxanthin, which is widely used as an additive for natural pigmentation. In addition, astaxanthin has recently garnered commercial interest as a nutraceutical, cosmetic, and pharmaceutical. However, producing astaxanthin from H. pluvialis necessitates separation with distinctive culture conditions, dividing between the microalgae growth and the astaxanthin production stages. Light-emitting diodes (LEDs) have emerged as a replacement for traditional light sources, and LED applications are now rapidly expanding to multiple areas in fields such as biotechnology. However, further detail application into microalgae biotechnology remains limited. In this study, we have attempted to establish new protocols based on the specific wavelength of LEDs for the cultivation and production of astaxanthin using H. pluvialis. Specifically, we applied red LEDs for microalgae cell growth and then switched to blue LEDs to induce astaxanthin biosynthesis. The result showed that astaxanthin productions based on a wavelength shift from red to blue were significantly increased, compared to those with continuous illumination using red LEDs. Furthermore, additional increase of astaxanthin production was achieved with simultaneous application of exogenous carbon with blue LED illumination. Our approach based on the proper manipulation of LED wavelengths upon H. pluvialis cell stages will enable the improvement of biomass and enhance astaxanthin production using H. pluvialis. PMID:26860938

  7. Hormonal Regulation and Expression Profiles of Wheat Genes Involved during Phytic Acid Biosynthesis Pathway

    OpenAIRE

    Sipla Aggarwal; Vishnu Shukla; Kaushal Kumar Bhati; Mandeep Kaur; Shivani Sharma; Anuradha Singh; Shrikant Mantri; Ajay Kumar Pandey

    2015-01-01

    Phytic acid (PA) biosynthesis pathway genes were reported from multiple crop species. PA accumulation was enhanced during grain filling and at that time, hormones like Abscisic acid (ABA) and Gibberellic acid (GA3) interplay to control the process of seed development. Regulation of wheat PA pathway genes has not yet been reported in seeds. In an attempt to find the clues for the regulation by hormones, the promoter region of wheat PA pathway genes was analyzed for the presence of cis-elements...

  8. Protection of Astaxanthin in Astaxanthin Nanodispersions Using Additional Antioxidants

    OpenAIRE

    Chin Ping Tan; Imededdine Arbi Nehdi; Navideh Anarjan

    2013-01-01

    The protective effects of α-tocopherol and ascorbic acid on astaxanthin in astaxanthin nanodispersions produced via a solvent-diffusion technique and stabilized by a three-component stabilizer system, were studied either individually or in combination by using response surface methodology. Generally, both α-tocopherol and ascorbic acid could retard the astaxanthin degradation in astaxanthin nanodispersions. The results showed that the using α-tocopherol and ascorbic acid can be more efficient...

  9. A new paradigm for producing astaxanthin from the unicellular green alga Haematococcus pluvialis.

    Science.gov (United States)

    Zhang, Zhen; Wang, Baobei; Hu, Qiang; Sommerfeld, Milton; Li, Yuanguang; Han, Danxiang

    2016-10-01

    The unicellular green alga Haematococcus pluvialis has been exploited as a cell factory to produce the high-value antioxidant astaxanthin for over two decades, due to its superior ability to synthesize astaxanthin under adverse culture conditions. However, slow vegetative growth under favorable culture conditions and cell deterioration or death under stress conditions (e.g., high light, nitrogen starvation) has limited the astaxanthin production. In this study, a new paradigm that integrated heterotrophic cultivation, acclimation of heterotrophically grown cells to specific light/nutrient regimes, followed by induction of astaxanthin accumulation under photoautotrophic conditions was developed. First, the environmental conditions such as pH, carbon source, nitrogen regime, and light intensity, were optimized to induce astaxanthin accumulation in the dark-grown cells. Although moderate astaxanthin content (e.g., 1% of dry weight) and astaxanthin productivity (2.5 mg L(-1)  day(-1) ) were obtained under the optimized conditions, a considerable number of cells died off when subjected to stress for astaxanthin induction. To minimize the susceptibility of dark-grown cells to light stress, the algal cells were acclimated, prior to light induction of astaxanthin biosynthesis, under moderate illumination in the presence of nitrogen. Introduction of this strategy significantly reduced the cell mortality rate under high-light and resulted in increased cellular astaxanthin content and astaxanthin productivity. The productivity of astaxanthin was further improved to 10.5 mg L(-1)  day(-1) by implementation of such a strategy in a bubbling column photobioreactor. Biochemical and physiological analyses suggested that rebuilding of photosynthetic apparatus including D1 protein and PsbO, and recovery of PSII activities, are essential for acclimation of dark-grown cells under photo-induction conditions. Biotechnol. Bioeng. 2016;113: 2088-2099. © 2016 The Authors

  10. Biosynthesis of the labdane diterpene marrubiin in Marrubium vulgare via a non-mevalonate pathway.

    Science.gov (United States)

    Knöss, W; Reuter, B; Zapp, J

    1997-09-01

    The biosynthesis of the furanic labdane diterpene marrubiin has been studied in plantlets and shoot cultures of Marrubium vulgare (Lamiaceae). The use of [2-14C]acetate, [2-14C]pyruvate, [2-14C]mevalonic acid and [U-14C]glucose incorporation experiments showed that the labelling of sterols in etiolated shoot cultures of M. vulgare was in accordance with their biosynthesis via the acetate-mevalonate pathway. In contrast, the incorporation rates of these precursors into the diterpene marrubiin could not be explained by biosynthesis of this compound via the acetate-mevalonate pathway. Cultivation of etiolated shoot cultures of M. vulgare on medium containing [1-13C]glucose and subsequent 13C-NMR spectroscopy of marrubiin led to the conclusion that the biosynthesis of marrubiin follows a non-mevalonate pathway. All isoprenic units of 13C-labelled marrubiin were enriched in those carbons that correspond to positions 1 and 5 of a putative precursor isopentenyl diphosphate. This labelling pattern from [1-13C]glucose is consistent with an alternative pathway via trioses, which has already been shown to occur in Eubacteria and Gymnospermae. The labdane skeleton is a precursor of many other skeletal types of diterpenes. Therefore it becomes obvious that in connection with the few known examples of a non-mevalonate pathway to isoprenoids the formation of some isoprenoids in plants via a non-mevalonate pathway might be quite common. PMID:9291117

  11. Two distinct pathways for essential metabolic precursors for isoprenoid biosynthesis

    OpenAIRE

    Kuzuyama, Tomohisa; Seto, Haruo

    2012-01-01

    Isoprenoids are a diverse group of molecules found in all organisms, where they perform such important biological functions as hormone signaling (e.g., steroids) in mammals, antioxidation (e.g., carotenoids) in plants, electron transport (e.g., ubiquinone), and cell wall biosynthesis intermediates in bacteria. All isoprenoids are synthesized by the consecutive condensation of the five-carbon monomer isopentenyl diphosphate (IPP) to its isomer, dimethylallyl diphosphate (DMAPP). The biosynthet...

  12. Simultaneous Production of Triacylglycerol and High-Value Carotenoids by the Astaxanthin-Producing Oleaginous Green Microalga Chlorella zofingiensis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jin; Mao, Xuemei; Zhou, Wenguang; Guarnieri, Michael T.

    2016-08-01

    The production of lipids and astaxanthin, a high-value carotenoid, by Chlorella zofingiensis was investigated under different culture conditions. Comparative analysis revealed a good correlation between triacylglycerol (TAG) and astaxanthin accumulation in C. zofingiensis. Stress conditions promoted cell size and weight and induced the accumulation of neutral lipids, especially TAG and astaxanthin, with a concomitant decrease in membrane lipids. The highest contents of TAG and astaxanthin achieved were 387 and 4.89 mg g-1 dry weight, respectively. A semi-continuous culture strategy was developed to optimize the TAG and astaxanthin productivities, which reached 297 and 3.3 mg L-1 day-1, respectively. Additionally, astaxanthin accumulation was enhanced by inhibiting de novo fatty acid biosynthesis. In summary, our study represents a pioneering work of utilizing Chlorella for the integrated production of lipids and high-value products and C. zofingiensis has great potential to be a promising production strain and serve as an emerging oleaginous model alga.

  13. An Alternative Pathway for Formononetin Biosynthesis in Pueraria lobata.

    Science.gov (United States)

    Li, Jia; Li, Changfu; Gou, Junbo; Wang, Xin; Fan, Rongyan; Zhang, Yansheng

    2016-01-01

    The O-methylation is an important tailing process in Pueraria lobata isoflavone metabolism, but the molecular mechanism governing it remains not elucidated. This manuscript describes the mining of key O-methyltransferases (OMTs) involved in the process. Using our previously constructed P. lobata transcriptome, the OMT candidates were searched, extensively analyzed, and their functions were investigated by expression in yeast, Escherichia coli, or Glycine max hairy roots. Here, we report the identification of the key OMT gene responsible for formononetin production in P. lobata (designated as PlOMT9). PlOMT9 primarily functions as an isoflavone-specific 4'-O-methyltransferase, although it shows high sequence identities with isoflavone 7-O-methyltransferases. Moreover, unlike the previously reported OMTs that catalyze the 4'-O-methylation for formononetin biosynthesis at the isoflavanone stage, PlOMT9 performs this modifying step at the isoflavone level, using daidzein rather than 2,7,4'-trihydroxy-isoflavanone as the substrate. Gene expression analyses and metabolite profiling supported its proposed roles in P. lobata. Using the system of transgenic G. max hairy roots, the role of PlOMT9 in the biosynthesis of formononetin was further demonstrated in vivo. PMID:27379141

  14. Methionine salvage pathway in relation to ethylene biosynthesis

    International Nuclear Information System (INIS)

    The recycling of methionine during ethylene biosynthesis (the methionine cycle) was studied. During ethylene biosynthesis, the H3CS-group of S-adenosylmethionine (SAM) is released at 5'-methylthioadenosine (MTA), which is recycled to methionine via 5'-methylthioribose (MTS). In mungbean hypocotyls and cell-free extracts of avocado fruit, [14C]MTR was converted to labeled methionine via 2-keto-4-methylthiobutyric acid (KMB) and 2-hydroxy-4-methylthiobutyric acid (HMB) as intermediates. Radioactive tracer studies showed that KMB was converted readily in vivo and in vitro to methionine, while HMB was converted much more slowly. The conversion of KMB to methionine by dialyzed avocado extract required an amino group donor. Among several potential donors tested, L-glutamine was the most efficient. Incubation of [ribose-U-14C]MTR with avocado extract resulted in the production of [14C]formate, with little evolution of other 14C-labeled one-carbon compounds, indicating that the conversion of MTR to KMB involves a loss of formate, presumably from C-1 of MTR

  15. Functional characterization of various algal carotenoid ketolases reveals that ketolating zeaxanthin efficiently is essential for high production of astaxanthin in transgenic Arabidopsis

    OpenAIRE

    Zhong, Yu-Juan; Huang, Jun-Chao; Liu, Jin; Li, Yin; Jiang, Yue; Xu, Zeng-Fu; Sandmann, Gerhard; Chen, Feng

    2011-01-01

    Extending the carotenoid pathway to astaxanthin in plants is of scientific and industrial interest. However, expression of a microbial β-carotene ketolase (BKT) that catalyses the formation of ketocarotenoids in transgenic plants typically results in low levels of astaxanthin. The low efficiency of BKTs in ketolating zeaxanthin to astaxanthin is proposed to be the major limitation for astaxanthin accumulation in engineered plants. To verify this hypothesis, several algal BKTs were functionall...

  16. Protection of Astaxanthin in Astaxanthin Nanodispersions Using Additional Antioxidants

    Directory of Open Access Journals (Sweden)

    Chin Ping Tan

    2013-07-01

    Full Text Available The protective effects of α-tocopherol and ascorbic acid on astaxanthin in astaxanthin nanodispersions produced via a solvent-diffusion technique and stabilized by a three-component stabilizer system, were studied either individually or in combination by using response surface methodology. Generally, both α-tocopherol and ascorbic acid could retard the astaxanthin degradation in astaxanthin nanodispersions. The results showed that the using α-tocopherol and ascorbic acid can be more efficient in increasing the chemical stability of nanodispersions in comparison to using them individually. Using a response surface methodology (RSM response optimizer, it was seen that addition of ascorbic acid (ascorbic acid/astaxanthin w/w and α-tocopherol (α-tocopherol/astaxanthin w/w in proportions of 0.4 and 0.6, respectively, would give the maximum chemical stability to the studied astaxanthin nanodispersions.

  17. The Alternative Haem Biosynthesis Pathway: Structure, Function and Properties of Sirohaem Decarboxylase

    OpenAIRE

    Palmer, David James

    2014-01-01

    Haem, a cyclic tetrapyrrole, is found in organisms from all three domains of life. Haem is a prosthetic group for many proteins involved in essential biological processes such as respiration and oxygen transport. Synthesis of haem in eukaryotes and most bacteria follows a well defined route with highly conserved intermediates. However, an alternative haem biosynthesis pathway in Archaea and some bacteria was recently elucidated. This newly discovered pathway utilises sirohaem as a metabolic i...

  18. Surprising Arginine Biosynthesis: a Reappraisal of the Enzymology and Evolution of the Pathway in Microorganisms

    OpenAIRE

    Xu, Ying; Labedan, Bernard; Glansdorff, Nicolas

    2007-01-01

    Summary: Major aspects of the pathway of de novo arginine biosynthesis via acetylated intermediates in microorganisms must be revised in light of recent enzymatic and genomic investigations. The enzyme N-acetylglutamate synthase (NAGS), which used to be considered responsible for the first committed step of the pathway, is present in a limited number of bacterial phyla only and is absent from Archaea. In many Bacteria, shorter proteins related to the Gcn5-related N-acetyltransferase family ap...

  19. Auxin biosynthesis in pea: characterization of the tryptamine pathway.

    Science.gov (United States)

    Quittenden, Laura J; Davies, Noel W; Smith, Jason A; Molesworth, Peter P; Tivendale, Nathan D; Ross, John J

    2009-11-01

    One pathway leading to the bioactive auxin, indole-3-acetic acid (IAA), is known as the tryptamine pathway, which is suggested to proceed in the sequence: tryptophan (Trp), tryptamine, N-hydroxytryptamine, indole-3-acetaldoxime, indole-3-acetaldehyde (IAAld), IAA. Recently, this pathway has been characterized by the YUCCA genes in Arabidopsis (Arabidopsis thaliana) and their homologs in other species. YUCCA is thought to be responsible for the conversion of tryptamine to N-hydroxytryptamine. Here we complement the genetic findings with a compound-based approach in pea (Pisum sativum), detecting potential precursors by gas chromatography/tandem-mass spectrometry. In addition, we have synthesized deuterated forms of many of the intermediates involved, and have used them to quantify the endogenous compounds, and to investigate their metabolic fates. Trp, tryptamine, IAAld, indole-3-ethanol, and IAA were detected as endogenous constituents, whereas indole-3-acetaldoxime and one of its products, indole-3-acetonitrile, were not detected. Metabolism experiments indicated that the tryptamine pathway to IAA in pea roots proceeds in the sequence: Trp, tryptamine, IAAld, IAA, with indole-3-ethanol as a side-branch product of IAAld. N-hydroxytryptamine was not detected, but we cannot exclude that it is an intermediate between tryptamine and IAAld, nor can we rule out the possibility of a Trp-independent pathway operating in pea roots. PMID:19710233

  20. Sterol Biosynthesis Pathway as Target for Anti-trypanosomatid Drugs

    OpenAIRE

    Wanderley de Souza; Juliany Cola Fernandes Rodrigues

    2009-01-01

    Sterols are constituents of the cellular membranes that are essential for their normal structure and function. In mammalian cells, cholesterol is the main sterol found in the various membranes. However, other sterols predominate in eukaryotic microorganisms such as fungi and protozoa. It is now well established that an important metabolic pathway in fungi and in members of the Trypanosomatidae family is one that produces a special class of sterols, including ergosterol, and other 24-methyl st...

  1. Transcriptome Analysis of Manganese-deficient Chlamydomonas reinhardtii Provides Insight on the Chlorophyll Biosynthesis Pathway

    Energy Technology Data Exchange (ETDEWEB)

    Lockhart, Ainsley; Zvenigorodsky, Natasha; Pedraza, Mary Ann; Lindquist, Erika

    2011-08-11

    The biosynthesis of chlorophyll and other tetrapyrroles is a vital but poorly understood process. Recent genomic advances with the unicellular green algae Chlamydomonas reinhardtii have created opportunity to more closely examine the mechanisms of the chlorophyll biosynthesis pathway via transcriptome analysis. Manganese is a nutrient of interest for complex reactions because of its multiple stable oxidation states and role in molecular oxygen coordination. C. reinhardtii was cultured in Manganese-deplete Tris-acetate-phosphate (TAP) media for 24 hours and used to create cDNA libraries for sequencing using Illumina TruSeq technology. Transcriptome analysis provided intriguing insight on possible regulatory mechanisms in the pathway. Evidence supports similarities of GTR (Glutamyl-tRNA synthase) to its Chlorella vulgaris homolog in terms of Mn requirements. Data was also suggestive of Mn-related compensatory up-regulation for pathway proteins CHLH1 (Manganese Chelatase), GUN4 (Magnesium chelatase activating protein), and POR1 (Light-dependent protochlorophyllide reductase). Intriguingly, data suggests possible reciprocal expression of oxygen dependent CPX1 (coproporphyrinogen III oxidase) and oxygen independent CPX2. Further analysis using RT-PCR could provide compelling evidence for several novel regulatory mechanisms in the chlorophyll biosynthesis pathway.

  2. An integrated approach to demonstrating the ANR pathway of proanthocyanidin biosynthesis in plants.

    Science.gov (United States)

    Peng, Qing-Zhong; Zhu, Yue; Liu, Zhong; Du, Ci; Li, Ke-Gang; Xie, De-Yu

    2012-09-01

    Proanthocyanidins (PAs) are oligomers or polymers of plant flavan-3-ols and are important to plant adaptation in extreme environmental conditions. The characterization of anthocyanidin reductase (ANR) and leucoanthocyanidin reductase (LAR) has demonstrated the different biogenesis of four stereo-configurations of flavan-3-ols. It is important to understand whether ANR and the ANR pathway widely occur in the plant kingdom. Here, we report an integrated approach to demonstrate the ANR pathway in plants. This includes different methods to extract native ANR from different tissues of eight angiosperm plants (Lotus corniculatus, Desmodium uncinatum, Medicago sativa, Hordeum vulgare, Vitis vinifera, Vitis bellula, Parthenocissus heterophylla, and Cerasus serrulata) and one fern plant (Dryopteris pycnopteroides), a general enzymatic analysis approach to demonstrate the ANR activity, high-performance liquid chromatography-based fingerprinting to demonstrate (-)-epicatechin and other flavan-3-ol molecules, and phytochemical analysis of PAs. Results demonstrate that in addition to leaves of M. sativa, tissues of other eight plants contain an active ANR pathway. Particularly, the leaves, flowers and pods of D. uncinatum, which is a model plant to study LAR and the LAR pathways, are demonstrated to express an active ANR pathway. This finding suggests that the ANR pathway involves PA biosynthesis in D. uncinatum. In addition, a sequence BLAST analysis reveals that ANR homologs have been sequenced in plants from both gymnosperms and angiosperms. These data show that the ANR pathway to PA biosynthesis occurs in both seed and seedless vascular plants. PMID:22678031

  3. Characterization of a C3 Deoxygenation Pathway Reveals a Key Branch Point in Aminoglycoside Biosynthesis.

    Science.gov (United States)

    Lv, Meinan; Ji, Xinjian; Zhao, Junfeng; Li, Yongzhen; Zhang, Chen; Su, Li; Ding, Wei; Deng, Zixin; Yu, Yi; Zhang, Qi

    2016-05-25

    Apramycin is a clinically interesting aminoglycoside antibiotic (AGA) containing a highly unique bicyclic octose moiety, and this octose is deoxygenated at the C3 position. Although the biosynthetic pathways for most 2-deoxystreptamine-containing AGAs have been well characterized, the pathway for apramycin biosynthesis, including the C3 deoxygenation process, has long remained unknown. Here we report detailed investigation of apramycin biosynthesis by a series of genetic, biochemical and bioinformatical studies. We show that AprD4 is a novel radical S-adenosyl-l-methionine (SAM) enzyme, which uses a noncanonical CX3CX3C motif for binding of a [4Fe-4S] cluster and catalyzes the dehydration of paromamine, a pseudodisaccharide intermediate in apramycin biosynthesis. We also show that AprD3 is an NADPH-dependent reductase that catalyzes the reduction of the dehydrated product from AprD4-catalyzed reaction to generate lividamine, a C3' deoxygenated product of paromamine. AprD4 and AprD3 do not form a tight catalytic complex, as shown by protein complex immunoprecipitation and other assays. The AprD4/AprD3 enzyme system acts on different pseudodisaccharide substrates but does not catalyze the deoxygenation of oxyapramycin, an apramycin analogue containing a C3 hydroxyl group on the octose moiety, suggesting that oxyapramycin and apramycin are partitioned into two parallel pathways at an early biosynthetic stage. Functional dissection of the C6 dehydrogenase AprQ shows the crosstalk between different AGA biosynthetic gene clusters from the apramycin producer Streptomyces tenebrarius, and reveals the remarkable catalytic versatility of AprQ. Our study highlights the intriguing chemistry in apramycin biosynthesis and nature's ingenuity in combinatorial biosynthesis of natural products. PMID:27120352

  4. Biosynthesis of promatrix metalloproteinase-9/chondroitin sulphate proteoglycan heteromer involves a Rottlerin-sensitive pathway.

    Directory of Open Access Journals (Sweden)

    Nabin Malla

    Full Text Available BACKGROUND: Previously we have shown that a fraction of the matrix metalloproteinase-9 (MMP-9 synthesized by the macrophage cell line THP-1 was bound to a chondroitin sulphate proteoglycan (CSPG core protein as a reduction sensitive heteromer. Several biochemical properties of the enzyme were changed when it was bound to the CSPG. METHODOLOGY/PRINCIPAL FINDINGS: By use of affinity chromatography, zymography, and radioactive labelling, various macrophage stimulators were tested for their effect on the synthesis of the proMMP-9/CSPG heteromer and its components by THP-1 cells. Of the stimulators, only PMA largely increased the biosynthesis of the heteromer. As PMA is an activator of PKC, we determined which PKC isoenzymes were expressed by performing RT-PCR and Western Blotting. Subsequently specific inhibitors were used to investigate their involvement in the biosynthesis of the heteromer. Of the inhibitors, only Rottlerin repressed the biosynthesis of proMMP-9/CSPG and its two components. Much lower concentrations of Rottlerin were needed to reduce the amount of CSPG than what was needed to repress the synthesis of the heteromer and MMP-9. Furthermore, Rottlerin caused a minor reduction in the activation of the PKC isoenzymes δ, ε, θ and υ (PKD3 in both control and PMA exposed cells. CONCLUSIONS/SIGNIFICANCE: The biosynthesis of the proMMP-9/CSPG heteromer and proMMP-9 in THP-1 cells involves a Rottlerin-sensitive pathway that is different from the Rottlerin sensitive pathway involved in the CSPG biosynthesis. MMP-9 and CSPGs are known to be involved in various physiological and pathological processes. Formation of complexes may influence both the specificity and localization of the enzyme. Therefore, knowledge about biosynthetic pathways and factors involved in the formation of the MMP-9/CSPG heteromer may contribute to insight in the heteromers biological function as well as pointing to future targets for therapeutic agents.

  5. Multicellular compartmentation of catharanthus roseus alkaloid biosynthesis predicts intercellular translocation of a pathway intermediate

    Science.gov (United States)

    St-Pierre, B; Vazquez-Flota, FA; De Luca V

    1999-01-01

    In situ RNA hybridization and immunocytochemistry were used to establish the cellular distribution of monoterpenoid indole alkaloid biosynthesis in Madagascar periwinkle (Catharanthus roseus). Tryptophan decarboxylase (TDC) and strictosidine synthase (STR1), which are involved in the biosynthesis of the central intermediate strictosidine, and desacetoxyvindoline 4-hydroxylase (D4H) and deacetylvindoline 4-O-acetyltransferase (DAT), which are involved in the terminal steps of vindoline biosynthesis, were localized. tdc and str1 mRNAs were present in the epidermis of stems, leaves, and flower buds, whereas they appeared in most protoderm and cortical cells around the apical meristem of root tips. In marked contrast, d4h and dat mRNAs were associated with the laticifer and idioblast cells of leaves, stems, and flower buds. Immunocytochemical localization for TDC, D4H, and DAT proteins confirmed the differential localization of early and late stages of vindoline biosynthesis. Therefore, we concluded that the elaboration of the major leaf alkaloids involves the participation of at least two cell types and requires the intercellular translocation of a pathway intermediate. A basipetal gradient of expression in maturing leaves also was shown for all four genes by in situ RNA hybridization studies and by complementary studies with dissected leaves, suggesting that expression of the vindoline pathway occurs transiently during early leaf development. These results partially explain why attempts to produce vindoline by cell culture technology have failed. PMID:10330473

  6. Tracking the sterol biosynthesis pathway of the diatom Phaeodactylum tricornutum

    OpenAIRE

    Fabris, M; Matthijs, M.; Carbonelle, S.; Moses, T.; Pollier, J.; Dasseville, R.; Baart, G.J.E.; Vyverman, W.; Goossens, A

    2014-01-01

    Diatoms are unicellular photosynthetic microalgae that play a major role in global primary production and aquatic biogeochemical cycling. Endosymbiotic events and recurrent gene transfers uniquely shaped the genome of diatoms, which contains features from several domains of life. The biosynthesis pathways of sterols, essential compounds in all eukaryotic cells, and many of the enzymes involved are evolutionarily conserved in eukaryotes. Although well characterized in most eukaryotes, the path...

  7. Aromatic Glucosinolate Biosynthesis Pathway in Barbarea vulgaris and its Response to Plutella xylostella Infestation

    OpenAIRE

    Liu, Tongjin; Zhang, Xiaohui; Yang, Haohui; Agerbirk, Niels; Qiu, Yang; Wang, Haiping; Shen, Di; Song, Jiangping; Li, Xixiang

    2016-01-01

    The inducibility of the glucosinolate resistance mechanism is an energy-saving strategy for plants, but whether induction would still be triggered by glucosinolate-tolerant Plutella xylostella (diamondback moth, DBM) after a plant had evolved a new resistance mechanism (e.g., saponins in Barbara vulgaris) was unknown. In B. vulgaris, aromatic glucosinolates derived from homo-phenylalanine are the dominant glucosinolates, but their biosynthesis pathway was unclear. In this study, we used G-typ...

  8. RNA-Seq analysis for indigo biosynthesis pathway genes in Indigofera tinctoria and Polygonum tinctorium

    Directory of Open Access Journals (Sweden)

    Bijaya K. Sarangi

    2015-12-01

    Full Text Available Natural indigo is the most important blue dye for textile dyeing and valuable secondary metabolite biosynthesized in Indigofera tinctoria and Polygonum tinctorium plants. Present investigation is made to generation of gene resource for pathway enrichment and to understand possible gene expression involved in indigo biosynthesis. The data about raw reads and the transcriptome assembly project has been deposited at GenBank under the accessions SRA180766 and SRX692542 for I. tinctoria and P. tinctorium, respectively.

  9. RNA-Seq analysis for indigo biosynthesis pathway genes in Indigofera tinctoria and Polygonum tinctorium.

    Science.gov (United States)

    Sarangi, Bijaya K; Minami, Yoshiko; Thul, Sanjog T

    2015-12-01

    Natural indigo is the most important blue dye for textile dyeing and valuable secondary metabolite biosynthesized in Indigofera tinctoria and Polygonum tinctorium plants. Present investigation is made to generation of gene resource for pathway enrichment and to understand possible gene expression involved in indigo biosynthesis. The data about raw reads and the transcriptome assembly project has been deposited at GenBank under the accessions SRA180766 and SRX692542 for I. tinctoria and P. tinctorium, respectively. PMID:26697377

  10. RNA-Seq analysis for indigo biosynthesis pathway genes in Indigofera tinctoria and Polygonum tinctorium

    OpenAIRE

    Bijaya K. Sarangi; Yoshiko Minami; Thul, Sanjog T.

    2015-01-01

    Natural indigo is the most important blue dye for textile dyeing and valuable secondary metabolite biosynthesized in Indigofera tinctoria and Polygonum tinctorium plants. Present investigation is made to generation of gene resource for pathway enrichment and to understand possible gene expression involved in indigo biosynthesis. The data about raw reads and the transcriptome assembly project has been deposited at GenBank under the accessions SRA180766 and SRX692542 for I. tinctoria and P. tin...

  11. Protective Effect of Astaxanthin on Liver Fibrosis through Modulation of TGF-β1 Expression and Autophagy

    OpenAIRE

    Shen, Miao; CHEN, KAN; Lu, Jie; Cheng, Ping; Ling XU; Dai, Weiqi; Wang, Fan; He, Lei; Yan ZHANG; Chengfen, Wang; Li, Jingjing; Yang, Jing; Zhu, Rong; Zhang, Huawei; Zheng, Yuanyuan

    2014-01-01

    Liver fibrosis is a common pathway leading to cirrhosis and a worldwide clinical issue. Astaxanthin is a red carotenoid pigment with antioxidant, anticancer, and anti-inflammatory properties. The aim of this study was to investigate the effect of astaxanthin on liver fibrosis and its potential protective mechanisms. Liver fibrosis was induced in a mouse model using CCL4 (intraperitoneal injection, three times a week for 8 weeks), and astaxanthin was administered everyday at three doses (20, 4...

  12. GAME9 regulates the biosynthesis of steroidal alkaloids and upstream isoprenoids in the plant mevalonate pathway.

    Science.gov (United States)

    Cárdenas, Pablo D; Sonawane, Prashant D; Pollier, Jacob; Vanden Bossche, Robin; Dewangan, Veena; Weithorn, Efrat; Tal, Lior; Meir, Sagit; Rogachev, Ilana; Malitsky, Sergey; Giri, Ashok P; Goossens, Alain; Burdman, Saul; Aharoni, Asaph

    2016-01-01

    Steroidal glycoalkaloids (SGAs) are cholesterol-derived molecules produced by solanaceous species. They contribute to pathogen defence but are toxic to humans and considered as anti-nutritional compounds. Here we show that GLYCOALKALOID METABOLISM 9 (GAME9), an APETALA2/Ethylene Response Factor, related to regulators of alkaloid production in tobacco and Catharanthus roseus, controls SGA biosynthesis. GAME9 knockdown and overexpression in tomato and potato alters expression of SGAs and upstream mevalonate pathway genes including the cholesterol biosynthesis gene STEROL SIDE CHAIN REDUCTASE 2 (SSR2). Levels of SGAs, C24-alkylsterols and the upstream mevalonate and cholesterol pathways intermediates are modified in these plants. Δ(7)-STEROL-C5(6)-DESATURASE (C5-SD) in the hitherto unresolved cholesterol pathway is a direct target of GAME9. Transactivation and promoter-binding assays show that GAME9 exerts its activity either directly or cooperatively with the SlMYC2 transcription factor as in the case of the C5-SD gene promoter. Our findings provide insight into the regulation of SGA biosynthesis and means for manipulating these metabolites in crops. PMID:26876023

  13. Simulation of a Petri net-based Model of the Terpenoid Biosynthesis Pathway

    Directory of Open Access Journals (Sweden)

    Hawari Aliah

    2010-02-01

    Full Text Available Abstract Background The development and simulation of dynamic models of terpenoid biosynthesis has yielded a systems perspective that provides new insights into how the structure of this biochemical pathway affects compound synthesis. These insights may eventually help identify reactions that could be experimentally manipulated to amplify terpenoid production. In this study, a dynamic model of the terpenoid biosynthesis pathway was constructed based on the Hybrid Functional Petri Net (HFPN technique. This technique is a fusion of three other extended Petri net techniques, namely Hybrid Petri Net (HPN, Dynamic Petri Net (HDN and Functional Petri Net (FPN. Results The biological data needed to construct the terpenoid metabolic model were gathered from the literature and from biological databases. These data were used as building blocks to create an HFPNe model and to generate parameters that govern the global behaviour of the model. The dynamic model was simulated and validated against known experimental data obtained from extensive literature searches. The model successfully simulated metabolite concentration changes over time (pt and the observations correlated with known data. Interactions between the intermediates that affect the production of terpenes could be observed through the introduction of inhibitors that established feedback loops within and crosstalk between the pathways. Conclusions Although this metabolic model is only preliminary, it will provide a platform for analysing various high-throughput data, and it should lead to a more holistic understanding of terpenoid biosynthesis.

  14. Ethanol induced astaxanthin accumulation and transcriptional expression of carotenogenic genes in Haematococcus pluvialis.

    Science.gov (United States)

    Wen, Zewen; Liu, Zhiyong; Hou, Yuyong; Liu, Chenfeng; Gao, Feng; Zheng, Yubin; Chen, Fangjian

    2015-10-01

    Haematococcus pluvialis is one of the most promising natural sources of astaxanthin. However, inducing the accumulation process has become one of the primary obstacles in astaxanthin production. In this study, the effect of ethanol on astaxanthin accumulation was investigated. The results demonstrated that astaxanthin accumulation occurred with ethanol addition even under low-light conditions. The astaxanthin productivity could reach 11.26 mg L(-1) d(-1) at 3% (v/v) ethanol, which was 2.03 times of that of the control. The transcriptional expression patterns of eight carotenogenic genes were evaluated using real-time PCR. The results showed that ethanol greatly enhanced transcription of the isopentenyl diphosphate (IPP) isomerase genes (ipi-1 and ipi-2), which were responsible for isomerization reaction of IPP and dimethylallyl diphosphate (DMAPP). This finding suggests that ethanol induced astaxanthin biosynthesis was up-regulated mainly by ipi-1 and ipi-2 at transcriptional level, promoting isoprenoid synthesis and substrate supply to carotenoid formation. Thus ethanol has the potential to be used as an effective reagent to induce astaxanthin accumulation in H. pluvialis. PMID:26215339

  15. Transcriptome and biochemical analyses revealed a detailed proanthocyanidin biosynthesis pathway in brown cotton fiber.

    Directory of Open Access Journals (Sweden)

    Yue-Hua Xiao

    Full Text Available Brown cotton fiber is the major raw material for colored cotton industry. Previous studies have showed that the brown pigments in cotton fiber belong to proanthocyanidins (PAs. To clarify the details of PA biosynthesis pathway in brown cotton fiber, gene expression profiles in developing brown and white fibers were compared via digital gene expression profiling and qRT-PCR. Compared to white cotton fiber, all steps from phenylalanine to PA monomers (flavan-3-ols were significantly up-regulated in brown fiber. Liquid chromatography mass spectrometry analyses showed that most of free flavan-3-ols in brown fiber were in 2, 3-trans form (gallocatechin and catechin, and the main units of polymeric PAs were trihydroxylated on B ring. Consistent with monomeric composition, the transcript levels of flavonoid 3', 5'-hydroxylase and leucoanthocyanidin reductase in cotton fiber were much higher than their competing enzymes acting on the same substrates (dihydroflavonol 4-reductase and anthocyanidin synthase, respectively. Taken together, our data revealed a detailed PA biosynthesis pathway wholly activated in brown cotton fiber, and demonstrated that flavonoid 3', 5'-hydroxylase and leucoanthocyanidin reductase represented the primary flow of PA biosynthesis in cotton fiber.

  16. Antihypertensive effects of astaxanthin

    OpenAIRE

    Hiroshi Yoshida; Kumie Ito; Hidekatsu Yanai; Norio Tada

    2008-01-01

    Hidekatsu Yanai1,2, Kumie Ito1,2, Hiroshi Yoshida2,3, Norio Tada1,21Department of Internal Medicine; 2Institute of Clinical Medicine and Research; 3Department of Laboratory Medicine, The Jikei University School of Medicine, Chiba, JapanAbstract: Astaxanthin is a biological antioxidant naturally found in a wide variety of aquatic living organisms, and has shown various pharmacological activities, such as anti-inflammatory and antidiabetic activities. A recent study reported that the administra...

  17. Transcriptome analysis of bitter acid biosynthesis and precursor pathways in hop (Humulus lupulus

    Directory of Open Access Journals (Sweden)

    Clark Shawn M

    2013-01-01

    Full Text Available Abstract Background Bitter acids (e.g. humulone are prenylated polyketides synthesized in lupulin glands of the hop plant (Humulus lupulus which are important contributors to the bitter flavour and stability of beer. Bitter acids are formed from acyl-CoA precursors derived from branched-chain amino acid (BCAA degradation and C5 prenyl diphosphates from the methyl-D-erythritol 4-phosphate (MEP pathway. We used RNA sequencing (RNA-seq to obtain the transcriptomes of isolated lupulin glands, cones with glands removed and leaves from high α-acid hop cultivars, and analyzed these datasets for genes involved in bitter acid biosynthesis including the supply of major precursors. We also measured the levels of BCAAs, acyl-CoA intermediates, and bitter acids in glands, cones and leaves. Results Transcripts encoding all the enzymes of BCAA metabolism were significantly more abundant in lupulin glands, indicating that BCAA biosynthesis and subsequent degradation occurs in these specialized cells. Branched-chain acyl-CoAs and bitter acids were present at higher levels in glands compared with leaves and cones. RNA-seq analysis showed the gland-specific expression of the MEP pathway, enzymes of sucrose degradation and several transcription factors that may regulate bitter acid biosynthesis in glands. Two branched-chain aminotransferase (BCAT enzymes, HlBCAT1 and HlBCAT2, were abundant, with gene expression quantification by RNA-seq and qRT-PCR indicating that HlBCAT1 was specific to glands while HlBCAT2 was present in glands, cones and leaves. Recombinant HlBCAT1 and HlBCAT2 catalyzed forward (biosynthetic and reverse (catabolic reactions with similar kinetic parameters. HlBCAT1 is targeted to mitochondria where it likely plays a role in BCAA catabolism. HlBCAT2 is a plastidial enzyme likely involved in BCAA biosynthesis. Phylogenetic analysis of the hop BCATs and those from other plants showed that they group into distinct biosynthetic (plastidial and

  18. Rhamnose biosynthesis pathway supplies precursors for primary and secondary metabolism in Saccharopolyspora spinosa.

    Science.gov (United States)

    Madduri, K; Waldron, C; Merlo, D J

    2001-10-01

    Rhamnose is an essential component of the insect control agent spinosad. However, the genes coding for the four enzymes involved in rhamnose biosynthesis in Saccharopolyspora spinosa are located in three different regions of the genome, all unlinked to the cluster of other genes that are required for spinosyn biosynthesis. Disruption of any of the rhamnose genes resulted in mutants with highly fragmented mycelia that could survive only in media supplemented with an osmotic stabilizer. It appears that this single set of genes provides rhamnose for cell wall synthesis as well as for secondary metabolite production. Duplicating the first two genes of the pathway caused a significant improvement in the yield of spinosyn fermentation products. PMID:11544225

  19. Absorption Spectra of Astaxanthin Aggregates

    CERN Document Server

    Olsina, Jan; Minofar, Babak; Polivka, Tomas; Mancal, Tomas

    2012-01-01

    Carotenoids in hydrated polar solvents form aggregates characterized by dramatic changes in their absorption spectra with respect to monomers. Here we analyze absorption spectra of aggregates of the carotenoid astaxanthin in hydrated dimethylsulfoxide. Depending on water content, two types of aggregates were produced: H-aggregates with absorption maximum around 390 nm, and J-aggregates with red-shifted absorption band peaking at wavelengths >550 nm. The large shifts with respect to absorption maximum of monomeric astaxanthin (470-495 nm depending on solvent) are caused by excitonic interaction between aggregated molecules. We applied molecular dynamics simulations to elucidate structure of astaxanthin dimer in water, and the resulting structure was used as a basis for calculations of absorption spectra. Absorption spectra of astaxanthin aggregates in hydrated dimethylsulfoxide were calculated using molecular exciton model with the resonance interaction energy between astaxanthin monomers constrained by semi-e...

  20. Astaxanthin-Producing Green Microalga Haematococcus pluvialis: From Single Cell to High Value Commercial Products

    Science.gov (United States)

    Shah, Md. Mahfuzur R.; Liang, Yuanmei; Cheng, Jay J.; Daroch, Maurycy

    2016-01-01

    Many species of microalgae have been used as source of nutrient rich food, feed, and health promoting compounds. Among the commercially important microalgae, Haematococcus pluvialis is the richest source of natural astaxanthin which is considered as “super anti-oxidant.” Natural astaxanthin produced by H. pluvialis has significantly greater antioxidant capacity than the synthetic one. Astaxanthin has important applications in the nutraceuticals, cosmetics, food, and aquaculture industries. It is now evident that, astaxanthin can significantly reduce free radicals and oxidative stress and help human body maintain a healthy state. With extraordinary potency and increase in demand, astaxanthin is one of the high-value microalgal products of the future.This comprehensive review summarizes the most important aspects of the biology, biochemical composition, biosynthesis, and astaxanthin accumulation in the cells of H. pluvialis and its wide range of applications for humans and animals. In this paper, important and recent developments ranging from cultivation, harvest and postharvest bio-processing technologies to metabolic control and genetic engineering are reviewed in detail, focusing on biomass and astaxanthin production from this biotechnologically important microalga. Simultaneously, critical bottlenecks and major challenges in commercial scale production; current and prospective global market of H. pluvialis derived astaxanthin are also presented in a critical manner. A new biorefinery concept for H. pluvialis has been also suggested to guide toward economically sustainable approach for microalgae cultivation and processing. This report could serve as a useful guide to present current status of knowledge in the field and highlight key areas for future development of H. pluvialis astaxanthin technology and its large scale commercial implementation. PMID:27200009

  1. Astaxanthin-Producing Green Microalga Haematococcus pluvialis: From Single Cell to High Value Commercial Products.

    Science.gov (United States)

    Shah, Md Mahfuzur R; Liang, Yuanmei; Cheng, Jay J; Daroch, Maurycy

    2016-01-01

    Many species of microalgae have been used as source of nutrient rich food, feed, and health promoting compounds. Among the commercially important microalgae, Haematococcus pluvialis is the richest source of natural astaxanthin which is considered as "super anti-oxidant." Natural astaxanthin produced by H. pluvialis has significantly greater antioxidant capacity than the synthetic one. Astaxanthin has important applications in the nutraceuticals, cosmetics, food, and aquaculture industries. It is now evident that, astaxanthin can significantly reduce free radicals and oxidative stress and help human body maintain a healthy state. With extraordinary potency and increase in demand, astaxanthin is one of the high-value microalgal products of the future.This comprehensive review summarizes the most important aspects of the biology, biochemical composition, biosynthesis, and astaxanthin accumulation in the cells of H. pluvialis and its wide range of applications for humans and animals. In this paper, important and recent developments ranging from cultivation, harvest and postharvest bio-processing technologies to metabolic control and genetic engineering are reviewed in detail, focusing on biomass and astaxanthin production from this biotechnologically important microalga. Simultaneously, critical bottlenecks and major challenges in commercial scale production; current and prospective global market of H. pluvialis derived astaxanthin are also presented in a critical manner. A new biorefinery concept for H. pluvialis has been also suggested to guide toward economically sustainable approach for microalgae cultivation and processing. This report could serve as a useful guide to present current status of knowledge in the field and highlight key areas for future development of H. pluvialis astaxanthin technology and its large scale commercial implementation. PMID:27200009

  2. Aromatic Glucosinolate Biosynthesis Pathway in Barbarea vulgaris and its Response to Plutella xylostella Infestation

    Science.gov (United States)

    Liu, Tongjin; Zhang, Xiaohui; Yang, Haohui; Agerbirk, Niels; Qiu, Yang; Wang, Haiping; Shen, Di; Song, Jiangping; Li, Xixiang

    2016-01-01

    The inducibility of the glucosinolate resistance mechanism is an energy-saving strategy for plants, but whether induction would still be triggered by glucosinolate-tolerant Plutella xylostella (diamondback moth, DBM) after a plant had evolved a new resistance mechanism (e.g., saponins in Barbara vulgaris) was unknown. In B. vulgaris, aromatic glucosinolates derived from homo-phenylalanine are the dominant glucosinolates, but their biosynthesis pathway was unclear. In this study, we used G-type (pest-resistant) and P-type (pest-susceptible) B. vulgaris to compare glucosinolate levels and the expression profiles of their biosynthesis genes before and after infestation by DBM larvae. Two different stereoisomers of hydroxylated aromatic glucosinolates are dominant in G- and P-type B. vulgaris, respectively, and are induced by DBM. The transcripts of genes in the glucosinolate biosynthesis pathway and their corresponding transcription factors were identified from an Illumina dataset of G- and P-type B. vulgaris. Many genes involved or potentially involved in glucosinolate biosynthesis were induced in both plant types. The expression patterns of six DBM induced genes were validated by quantitative PCR (qPCR), while six long-fragment genes were validated by molecular cloning. The core structure biosynthetic genes showed high sequence similarities between the two genotypes. In contrast, the sequence identity of two apparent side chain modification genes, the SHO gene in the G-type and the RHO in P-type plants, showed only 77.50% identity in coding DNA sequences and 65.48% identity in deduced amino acid sequences. The homology to GS-OH in Arabidopsis, DBM induction of the transcript and a series of qPCR and glucosinolate analyses of G-type, P-type and F1 plants indicated that these genes control the production of S and R isomers of 2-hydroxy-2-phenylethyl glucosinolate. These glucosinolates were significantly induced by P. xylostella larvae in both the susceptiple P

  3. Aromatic Glucosinolate Biosynthesis Pathway in Barbarea vulgaris and its Response to Plutella xylostella Infestation.

    Science.gov (United States)

    Liu, Tongjin; Zhang, Xiaohui; Yang, Haohui; Agerbirk, Niels; Qiu, Yang; Wang, Haiping; Shen, Di; Song, Jiangping; Li, Xixiang

    2016-01-01

    The inducibility of the glucosinolate resistance mechanism is an energy-saving strategy for plants, but whether induction would still be triggered by glucosinolate-tolerant Plutella xylostella (diamondback moth, DBM) after a plant had evolved a new resistance mechanism (e.g., saponins in Barbara vulgaris) was unknown. In B. vulgaris, aromatic glucosinolates derived from homo-phenylalanine are the dominant glucosinolates, but their biosynthesis pathway was unclear. In this study, we used G-type (pest-resistant) and P-type (pest-susceptible) B. vulgaris to compare glucosinolate levels and the expression profiles of their biosynthesis genes before and after infestation by DBM larvae. Two different stereoisomers of hydroxylated aromatic glucosinolates are dominant in G- and P-type B. vulgaris, respectively, and are induced by DBM. The transcripts of genes in the glucosinolate biosynthesis pathway and their corresponding transcription factors were identified from an Illumina dataset of G- and P-type B. vulgaris. Many genes involved or potentially involved in glucosinolate biosynthesis were induced in both plant types. The expression patterns of six DBM induced genes were validated by quantitative PCR (qPCR), while six long-fragment genes were validated by molecular cloning. The core structure biosynthetic genes showed high sequence similarities between the two genotypes. In contrast, the sequence identity of two apparent side chain modification genes, the SHO gene in the G-type and the RHO in P-type plants, showed only 77.50% identity in coding DNA sequences and 65.48% identity in deduced amino acid sequences. The homology to GS-OH in Arabidopsis, DBM induction of the transcript and a series of qPCR and glucosinolate analyses of G-type, P-type and F1 plants indicated that these genes control the production of S and R isomers of 2-hydroxy-2-phenylethyl glucosinolate. These glucosinolates were significantly induced by P. xylostella larvae in both the susceptiple P

  4. MRE: a web tool to suggest foreign enzymes for the biosynthesis pathway design with competing endogenous reactions in mind

    KAUST Repository

    Kuwahara, Hiroyuki

    2016-04-29

    To rationally design a productive heterologous biosynthesis system, it is essential to consider the suitability of foreign reactions for the specific endogenous metabolic infrastructure of a host. We developed a novel web server, called MRE, which, for a given pair of starting and desired compounds in a given chassis organism, ranks biosynthesis routes from the perspective of the integration of new reactions into the endogenous metabolic system. For each promising heterologous biosynthesis pathway, MRE suggests actual enzymes for foreign metabolic reactions and generates information on competing endogenous reactions for the consumption of metabolites. These unique, chassis-centered features distinguish MRE from existing pathway design tools and allow synthetic biologists to evaluate the design of their biosynthesis systems from a different angle. By using biosynthesis of a range of high-value natural products as a case study, we show that MRE is an effective tool to guide the design and optimization of heterologous biosynthesis pathways. The URL of MRE is http://www.cbrc.kaust.edu.sa/mre/.

  5. MRE: a web tool to suggest foreign enzymes for the biosynthesis pathway design with competing endogenous reactions in mind.

    Science.gov (United States)

    Kuwahara, Hiroyuki; Alazmi, Meshari; Cui, Xuefeng; Gao, Xin

    2016-07-01

    To rationally design a productive heterologous biosynthesis system, it is essential to consider the suitability of foreign reactions for the specific endogenous metabolic infrastructure of a host. We developed a novel web server, called MRE, which, for a given pair of starting and desired compounds in a given chassis organism, ranks biosynthesis routes from the perspective of the integration of new reactions into the endogenous metabolic system. For each promising heterologous biosynthesis pathway, MRE suggests actual enzymes for foreign metabolic reactions and generates information on competing endogenous reactions for the consumption of metabolites. These unique, chassis-centered features distinguish MRE from existing pathway design tools and allow synthetic biologists to evaluate the design of their biosynthesis systems from a different angle. By using biosynthesis of a range of high-value natural products as a case study, we show that MRE is an effective tool to guide the design and optimization of heterologous biosynthesis pathways. The URL of MRE is http://www.cbrc.kaust.edu.sa/mre/. PMID:27131375

  6. Evidence from Solanum tuberosum in support of the dual-pathway hypothesis of aromatic biosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Morris, P.F.; Doong, R.L.; Jensen, R.A. (Univ. of Florida, Gainesville (USA))

    1989-01-01

    Key branchpoint enzymes of aromatic amino acid biosynthesis, 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase (DS) and chorismate mutase (CM), have previously been shown to exist as separate compartmentalized isozymes in the chloroplasts and cytosol of tobacco, sorghum and spinach. Although additional examples of plants containing these isozyme pairs are accumulating, some studies in the literature report the presence of only the single plastidic DS or CM enzyme. Such apparent exceptions contradict the universality of pathway organization existing in higher plants that is implied by the dual-pathway hypothesis of aromatic biosynthesis. Since potato (Solanum tuberosum) exemplifies a case where only a single species of both DS and CM have been reported, we selected this system for further analysis. The DS-Mn and DS-Co isozyme pair, exhibiting all of the differential properties described in Nicotiana silvestris, have now been identified in S. tuberosum. Likwise, partial purification via DEAE-cellulose chromatography revealed two isozymes of CM in disks excised from tubers of S. tuberosum. The differential regulatory properties of these isozymes were comparable to the CM-1 and CM-2 isozymes of N. silvestris.

  7. Reconstruction of the carnitine biosynthesis pathway from Neurospora crassa in the yeast Saccharomyces cerevisiae.

    Science.gov (United States)

    Franken, Jaco; Burger, Anita; Swiegers, Jan H; Bauer, Florian F

    2015-08-01

    Industrial synthesis of L-carnitine is currently performed by whole-cell biotransformation of industrial waste products, mostly D-carnitine and cronobetaine, through specific bacterial species. No comparable system has been established using eukaryotic microorganisms, even though there is a significant and growing international demand for either the pure compound or carnitine-enriched consumables. In eukaryotes, including the fungus Neurospora crassa, L-carnitine is biosynthesized through a four-step metabolic conversion of trimethyllysine to L-carnitine. In contrast, the industrial yeast, Saccharomyces cerevisiae lacks the enzymes of the eukaryotic biosynthesis pathway and is unable to synthesize carnitine. This study describes the cloning of all four of the N. crassa carnitine biosynthesis genes and the reconstruction of the entire pathway in S. cerevisiae. The engineered yeast strains were able to catalyze the synthesis of L-carnitine, which was quantified using hydrophilic interaction liquid chromatography electrospray ionization mass spectrometry (HILIC-ESI-MS) analyses, from trimethyllysine. Furthermore, the yeast threonine aldolase Gly1p was shown to effectively catalyze the second step of the pathway, fulfilling the role of a serine hydroxymethyltransferase. The analyses also identified yeast enzymes that interact with the introduced pathway, including Can1p, which was identified as the yeast transporter for trimethyllysine, and the two yeast serine hydroxymethyltransferases, Shm1p and Shm2p. Together, this study opens the possibility of using an engineered, carnitine-producing yeast in various industrial applications while providing insight into possible future strategies aimed at tailoring the production capacity of such strains. PMID:25851717

  8. Steroidogenic pathways involved in androgen biosynthesis in eumenorrheic women and patients with polycystic ovary syndrome.

    Science.gov (United States)

    Saito, Kazuki; Matsuzaki, Toshiya; Iwasa, Takeshi; Miyado, Mami; Saito, Hidekazu; Hasegawa, Tomonobu; Homma, Keiko; Inoue, Eisuke; Miyashiro, Yoshimichi; Kubota, Toshiro; Irahara, Minoru; Ogata, Tsutomu; Fukami, Maki

    2016-04-01

    The conventional Δ5 and Δ4 steroidogenic pathways mediate androgen production in females. While multiple non-conventional pathways to dihydrotestosterone (DHT) have recently been postulated in humans, the functional significance of these pathways remains to be elucidated. The aim of this study was to clarify the origin of androgens in healthy women and in patients with polycystic ovary syndrome (PCOS), a multifactorial disorder characterized by androgen overproduction. We measured 13 steroids in blood samples of 31 eumenorrheic females and 28 PCOS patients using liquid chromatography-tandem mass spectrometry and chemiluminescent enzyme immunoassay. We found that 17-hydroxy (17-OH) progesterone (17-OHP), androstenedione (Δ4A), testosterone, androstanedione, androsterone, and androstanediol levels were higher in the patient group than in the eumenorrheic group, while levels of other steroids were comparable between the two groups. In the eumenorrheic group, DHT levels were correlated with testosterone, androstanedione, and androstanediol. Quantitative correlations were also observed among 17-OH allopregnanolone, androsterone, androstanediol, and DHT, and among Δ4A, androstanedione, androsterone, and androstanediol. In the patient group, DHT levels were correlated with testosterone levels, but not with androstanedione or androstanediol levels. Δ4A and testosterone paralleled 17-OHP. Androstanedione, androsterone, androstanediol, and 17-OH allopregnanolone were quantitatively correlated. In both groups, multivariable linear regression analyses suggested relationships between androsterone and androstanedione, as well as between androsterone and 17-OH allopregnanolone. These results indicate that multiple androgen biosynthesis pathways are operating in eumenorrheic females and PCOS patients. In PCOS patients, excessive androgens are produced primarily via the conventional pathways, while two alternative pathways; i.e., an androstanedione-mediated pathway and a so

  9. A comprehensive analysis of fifteen genes of steviol glycosides biosynthesis pathway in Stevia rebaudiana (Bertoni).

    Science.gov (United States)

    Kumar, Hitesh; Kaul, Kiran; Bajpai-Gupta, Suphla; Kaul, Vijay Kumar; Kumar, Sanjay

    2012-01-15

    Stevia [Stevia rebuaidana (Bertoni); family: Asteraceae] is known to yield diterpenoid steviol glycosides (SGs), which are about 300 times sweeter than sugar. The present work analyzed the expression of various genes of the SGs biosynthesis pathway in different organs of the plant in relation to the SGs content. Of the various genes of the pathway, SrDXS, SrDXR, SrCPPS, SrKS, SrKO and three glucosyltransferases namely SrUGT85C2, SrUGT74G1 and SrUGT76G1 were reported from stevia. Here, we report cloning of seven additional full-length cDNA sequences namely, SrMCT, SrCMK, SrMDS, SrHDS, SrHDR, SrIDI and SrGGDPS followed by expression analysis of all the fifteen genes vis-à-vis SGs content analysis. SGs content was highest in the leaf at 3rd node position (node position with reference to the apical leaf as the first leaf) as compared to the leaves at other node positions. Except for SrDXR and SrKO, gene expression was maximum in leaf at 1st node and minimum in leaf at 5th node. The expression of SrKO was highest in leaf at 3rd node while in case of SrDXR expression showed an increase up to 3rd leaf and decrease thereafter. SGs accumulated maximum in leaf tissue followed by stem and root, and similar was the pattern of expression of all the fifteen genes. The genes responded to the modulators of the terpenopids biosynthesis. Gibberellin (GA(3)) treatment up-regulated the expression of SrMCT, SrCMK, SrMDS and SrUGT74G1, whereas methyl jasmonate and kinetin treatment down-regulated the expression of all the fifteen genes of the pathway. PMID:22037480

  10. 21 CFR 73.35 - Astaxanthin.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Astaxanthin. 73.35 Section 73.35 Food and Drugs... ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.35 Astaxanthin. (a) Identity. (1) The color additive astaxanthin is 3, 3′-dihydroxy-β, β-carotene-4, 4′-dione. (2) Astaxanthin may be added to the fish feed...

  11. Potential Anti-Atherosclerotic Properties of Astaxanthin

    OpenAIRE

    Yoshimi Kishimoto; Hiroshi Yoshida; Kazuo Kondo

    2016-01-01

    Astaxanthin is a naturally occurring red carotenoid pigment classified as a xanthophyll, found in microalgae and seafood such as salmon, trout, and shrimp. This review focuses on astaxanthin as a bioactive compound and outlines the evidence associated with its potential role in the prevention of atherosclerosis. Astaxanthin has a unique molecular structure that is responsible for its powerful antioxidant activities by quenching singlet oxygen and scavenging free radicals. Astaxanthin has been...

  12. Evidence for a cytoplasmic pathway of oxalate biosynthesis in Aspergillus niger

    International Nuclear Information System (INIS)

    Oxalate accumulation of up to 8 g/liter was induced in Aspergillus niger by shifting the pH from 6 to 8. This required the presence of P/sub i/ and a nitrogen source and was inhibited by the protein synthesis inhibitor cycloheximide. Exogenously added 14CO2 was not incorporated into oxalate, but was incorporated into acetate and malate, thus indicating the biosynthesis of oxalate by hydrolytic cleavage of oxaloacetate. Inhibition of mitochondrial citrate metabolism by fluorocitrate did not significantly decrease the oxalate yield. The putative enzyme that was responsible for this oxaloacetate hydrolase (EC 3.7.1.1), which was induced de novo during the pH shift. Subcellular fractionation of oxalic acid-forming mycelia of A. niger showed that this enzyme is located in the cytoplasm of A. niger. The results are consistent with a cytoplasmic pathway of oxalate formation which does not involve the tricarboxylic acid cycle

  13. Biosynthesis of aphidicolin proceeds via the mevalonate pathway in the endophytic fungus Nigrospora sphaerica

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Adriana A.; Pupo, Monica T., E-mail: mtpupo@fcfrp.usp.b [Universidade de Sao Paulo (FCFRP/USP), Ribeirao Preto, SP (Brazil). Fac. de Ciencias Farmaceuticas. Dept. de Ciencias Farmaceuticas

    2011-07-01

    We have previously identified the endophytic fungus Nigrospora sphaerica as a prolific producer of the bioactive diterpene aphidicolin. Herein we report a study to establish the best conditions for the production of aphidicolin by N. sphaerica in Czapek medium. The sugar source (glucose and sucrose) and the incubation time (4-15 days) were optimized for further application on biosynthetic studies of the diterpene. The highest levels of production of aphidicolin were found on the 8{sup th} day with 1%-glucose and on the 12{sup th} day with 3%-sucrose based media. The biosynthesis of aphidicolin was investigated using [1-{sup 13}C]-D-glucose as a precursor, and showed that the isoprene units of aphidicolin are derived from the mevalonate pathway. (author)

  14. Surprising arginine biosynthesis: a reappraisal of the enzymology and evolution of the pathway in microorganisms.

    Science.gov (United States)

    Xu, Ying; Labedan, Bernard; Glansdorff, Nicolas

    2007-03-01

    Major aspects of the pathway of de novo arginine biosynthesis via acetylated intermediates in microorganisms must be revised in light of recent enzymatic and genomic investigations. The enzyme N-acetylglutamate synthase (NAGS), which used to be considered responsible for the first committed step of the pathway, is present in a limited number of bacterial phyla only and is absent from Archaea. In many Bacteria, shorter proteins related to the Gcn5-related N-acetyltransferase family appear to acetylate l-glutamate; some are clearly similar to the C-terminal, acetyl-coenzyme A (CoA) binding domain of classical NAGS, while others are more distantly related. Short NAGSs can be single gene products, as in Mycobacterium spp. and Thermus spp., or fused to the enzyme catalyzing the last step of the pathway (argininosuccinase), as in members of the Alteromonas-Vibrio group. How these proteins bind glutamate remains to be determined. In some Bacteria, a bifunctional ornithine acetyltransferase (i.e., using both acetylornithine and acetyl-CoA as donors of the acetyl group) accounts for glutamate acetylation. In many Archaea, the enzyme responsible for glutamate acetylation remains elusive, but possible connections with a novel lysine biosynthetic pathway arose recently from genomic investigations. In some Proteobacteria (notably Xanthomonadaceae) and Bacteroidetes, the carbamoylation step of the pathway appears to involve N-acetylornithine or N-succinylornithine rather than ornithine. The product N-acetylcitrulline is deacetylated by an enzyme that is also involved in the provision of ornithine from acetylornithine; this is an important metabolic function, as ornithine itself can become essential as a source of other metabolites. This review insists on the biochemical and evolutionary implications of these findings. PMID:17347518

  15. Astaxanthin uptake in domestic dogs and cats

    Directory of Open Access Journals (Sweden)

    Massimino Stefan

    2010-06-01

    Full Text Available Abstract Background Research on the uptake and transport of astaxanthin is lacking in most species. We studied the uptake of astaxanthin by plasma, lipoproteins and leukocytes in domestic dogs and cats. Methods Mature female Beagle dogs (18 to 19 mo old; 11 to 14 kg BW were dosed orally with 0, 0.1, 0.5, 2.5, 10 or 40 mg astaxanthin and blood taken at 0, 3, 6, 9, 12, 18 and 24 h post-administration (n = 8/treatment. Similarly, mature domestic short hair cats (12 mo old; 3 to 3.5 kg body weight were fed a single dose of 0, 0.02, 0.08, 0.4, 2, 5, or 10 mg astaxanthin and blood taken (n = 8/treatment at the same interval. Results Both dogs and cats showed similar biokinetic profiles. Maximal astaxanthin concentration in plasma was approximately 0.14 μmol/L in both species, and was observed at 6 h post-dosing. The plasma astaxanthin elimination half-life was 9 to 18 h. Astaxanthin was still detectable by 24 h in both species. In a subsequent study, dogs and cats were fed similar doses of astaxanthin daily for 15 to 16 d and astaxanthin uptake by plasma, lipoproteins, and leukocytes studied. In both species, plasma astaxanthin concentrations generally continued to increase through d 15 or 16 of supplementation. The astaxanthin was mainly associated with high density lipoprotein (HDL. In blood leukocytes, approximately half of the total astaxanthin was found in the mitochondria, with significant amounts also associated with the microsomes and nuclei. Conclusion Dogs and cats absorb astaxanthin from the diet. In the blood, the astaxanthin is mainly associated with HDL, and is taken up by blood leukocytes, where it is distributed to all subcellular organelles. Certain aspects of the biokinetic uptake of astaxanthin in dogs and cats are similar to that in humans.

  16. Deregulation of S-adenosylmethionine biosynthesis and regeneration improves methylation in the E. coli de novo vanillin biosynthesis pathway

    OpenAIRE

    Kunjapur, Aditya M.; Hyun, Jason C.; Prather, Kristala L. J.

    2016-01-01

    Background: Vanillin is an industrially valuable molecule that can be produced from simple carbon sources in engineered microorganisms such as Saccharomyces cerevisiae and Escherichia coli. In E. coli, de novo production of vanillin was demonstrated previously as a proof of concept. In this study, a series of data-driven experiments were performed in order to better understand limitations associated with biosynthesis of vanillate, which is the immediate precursor to vanillin. Results: Time-co...

  17. Deregulation of S-adenosylmethionine biosynthesis and regeneration improves methylation in the E. coli de novo vanillin biosynthesis pathway

    OpenAIRE

    Kunjapur, Aditya M.; Hyun, Jason C.; Prather, Kristala L. J.

    2016-01-01

    Background Vanillin is an industrially valuable molecule that can be produced from simple carbon sources in engineered microorganisms such as Saccharomyces cerevisiae and Escherichia coli. In E. coli, de novo production of vanillin was demonstrated previously as a proof of concept. In this study, a series of data-driven experiments were performed in order to better understand limitations associated with biosynthesis of vanillate, which is the immediate precursor to vanillin. Results Time-cour...

  18. Potential Anti-Atherosclerotic Properties of Astaxanthin.

    Science.gov (United States)

    Kishimoto, Yoshimi; Yoshida, Hiroshi; Kondo, Kazuo

    2016-02-01

    Astaxanthin is a naturally occurring red carotenoid pigment classified as a xanthophyll, found in microalgae and seafood such as salmon, trout, and shrimp. This review focuses on astaxanthin as a bioactive compound and outlines the evidence associated with its potential role in the prevention of atherosclerosis. Astaxanthin has a unique molecular structure that is responsible for its powerful antioxidant activities by quenching singlet oxygen and scavenging free radicals. Astaxanthin has been reported to inhibit low-density lipoprotein (LDL) oxidation and to increase high-density lipoprotein (HDL)-cholesterol and adiponectin levels in clinical studies. Accumulating evidence suggests that astaxanthin could exert preventive actions against atherosclerotic cardiovascular disease (CVD) via its potential to improve oxidative stress, inflammation, lipid metabolism, and glucose metabolism. In addition to identifying mechanisms of astaxanthin bioactivity by basic research, much more epidemiological and clinical evidence linking reduced CVD risk with dietary astaxanthin intake is needed. PMID:26861359

  19. De novo assembly of Eugenia uniflora L. transcriptome and identification of genes from the terpenoid biosynthesis pathway.

    Science.gov (United States)

    Guzman, Frank; Kulcheski, Franceli Rodrigues; Turchetto-Zolet, Andreia Carina; Margis, Rogerio

    2014-12-01

    Pitanga (Eugenia uniflora L.) is a member of the Myrtaceae family and is of particular interest due to its medicinal properties that are attributed to specialized metabolites with known biological activities. Among these molecules, terpenoids are the most abundant in essential oils that are found in the leaves and represent compounds with potential pharmacological benefits. The terpene diversity observed in Myrtaceae is determined by the activity of different members of the terpene synthase and oxidosqualene cyclase families. Therefore, the aim of this study was to perform a de novo assembly of transcripts from E. uniflora leaves and to annotation to identify the genes potentially involved in the terpenoid biosynthesis pathway and terpene diversity. In total, 72,742 unigenes with a mean length of 1048bp were identified. Of these, 43,631 and 36,289 were annotated with the NCBI non-redundant protein and Swiss-Prot databases, respectively. The gene ontology categorized the sequences into 53 functional groups. A metabolic pathway analysis with KEGG revealed 8,625 unigenes assigned to 141 metabolic pathways and 40 unigenes predicted to be associated with the biosynthesis of terpenoids. Furthermore, we identified four putative full-length terpene synthase genes involved in sesquiterpenes and monoterpenes biosynthesis, and three putative full-length oxidosqualene cyclase genes involved in the triterpenes biosynthesis. The expression of these genes was validated in different E. uniflora tissues. PMID:25443850

  20. Quantitative importance of the 25-hydroxylation pathway for bile acid biosynthesis in the rat

    International Nuclear Information System (INIS)

    During biosynthesis of bile acid, carbons 25-26-27 are removed from the cholesterol side chain. Side-chain oxidation begins either with hydroxylation at the 26-position, in which case the three-carbon fragment is released as propionic acid, or with hydroxylation at the 25-position, in which case the three-carbon fragment is released as acetone. In the present study, we have quantitated the relative importance of these two pathways in vivo by measuring production of [14C] acetone from [14C]-26-cholesterol. Four days after intraperitoneal injection of 20 to 40 muCi [14C]-26-cholesterol and 1 day after beginning a constant intravenous infusion of unlabeled acetone at 25 mumoles per kg per min, 6 male and 2 female Sprague-Dawley rats underwent breath collections. Expired acetone was trapped and purified as the 2,4-dinitrophenylhydrazine derivative. 14CO2 was trapped quantitatively using phenethylamine. Specific activity of breath acetone was multiplied times the acetone infusion rate to calculate production of [14C]acetone. [14C] Acetone production averaged 1.7% of total release of 14C from [14C]-26-cholesterol, estimated by 14CO2 output. The method was validated by showing that [14C] acetone production from [14C]isopropanol averaged 111% of the [14C]isopropanol infusion rate. We conclude that, in the normal rat, the 25-hydroxylation pathway accounts for less than 2% of bile acid synthesis

  1. Genetic analysis of pathway regulation for enhancing branched-chain amino acid biosynthesis in plants

    KAUST Repository

    Chen, Hao

    2010-08-01

    The branched-chain amino acids (BCAAs) valine, leucine and isoleucine are essential amino acids that play critical roles in animal growth and development. Animals cannot synthesize these amino acids and must obtain them from their diet. Plants are the ultimate source of these essential nutrients, and they synthesize BCAAs through a conserved pathway that is inhibited by its end products. This feedback inhibition has prevented scientists from engineering plants that accumulate high levels of BCAAs by simply over-expressing the respective biosynthetic genes. To identify components critical for this feedback regulation, we performed a genetic screen for Arabidopsis mutants that exhibit enhanced resistance to BCAAs. Multiple dominant allelic mutations in the VALINE-TOLERANT 1 (VAT1) gene were identified that conferred plant resistance to valine inhibition. Map-based cloning revealed that VAT1 encodes a regulatory subunit of acetohydroxy acid synthase (AHAS), the first committed enzyme in the BCAA biosynthesis pathway. The VAT1 gene is highly expressed in young, rapidly growing tissues. When reconstituted with the catalytic subunit in vitro, the vat1 mutant-containing AHAS holoenzyme exhibits increased resistance to valine. Importantly, transgenic plants expressing the mutated vat1 gene exhibit valine tolerance and accumulate higher levels of BCAAs. Our studies not only uncovered regulatory characteristics of plant AHAS, but also identified a method to enhance BCAA accumulation in crop plants that will significantly enhance the nutritional value of food and feed. © 2010 Blackwell Publishing Ltd.

  2. Improvement of the riboflavin production by engineering the precursor biosynthesis pathways in Escherichia coli

    Institute of Scientific and Technical Information of China (English)

    Zhibo Xu; Zhenquan Lin; Zhiwen Wang; Tao Chen

    2015-01-01

    3,4-Dihydroxy-2-butanone 4-phosphate (DHBP) and GTP are the precursors for riboflavin biosynthesis. In this research, improving the precursor supply for riboflavin production was attempted by overexpressing ribB and engineering purine pathway in a riboflavin-producing Escherichia coli strain. Initially, ribB gene was overexpressed to increase the flux from ribulose 5-phosphate (Ru-5-P) to DHBP. Then ndk and gmk genes were overexpressed to enhance GTP supply. Subsequently, a R419L mutation was introduced into purA to reduce the flux from IMP to AMP. Finally, co-overexpression of mutant purF and prs genes further increased riboflavin production. The final strain RF18S produced 387.6 mg riboflavin · L−1 with a yield of 44.8 mg riboflavin per gram glucose in shake-flask fermentations. The final titer and yield were 72.2%and 55.6%higher than those of RF01S, respectively. It was concluded that simultaneously engineering the DHBP synthase and GTP biosynthetic pathway by rational metabolic engineering can efficiently boost riboflavin production in E. coli.

  3. Lysine Malonylome May Affect the Central Metabolism and Erythromycin Biosynthesis Pathway in Saccharopolyspora erythraea.

    Science.gov (United States)

    Xu, Jun-Yu; Xu, Zhen; Zhou, Ying; Ye, Bang-Ce

    2016-05-01

    Lysine acylation is a dynamic, reversible post-translational modification that can regulate cellular and organismal metabolism in bacteria. Acetylome has been studied well in bacteria. However, to our knowledge, there are no proteomic data on the lysine malonylation in prokaryotes, especially in actinomycetes, which are the major producers of therapeutic antibiotics. In our study, the first malonylome of the erythromycin-producing Saccharopolyspora erythraea was described by using a high-resolution mass spectrometry-based proteomics approach and high-affinity antimalonyllysine antibodies. We identified 192 malonylated sites on 132 substrates. Malonylated proteins are enriched in many biological processes such as protein synthesis, glycolysis and gluconeogenesis, the TCA cycle, and the feeder metabolic pathways of erythromycin synthesis according to GO analysis and KEGG pathway analysis. A total of 238 S/T/Y/H-phosphorylated sites on 158 proteins were also identified in our study, which aimed to explore the potential cross-talk between acylation and phosphorylation. After that, site-specific mutations showed that malonylation is a negative regulatory modification on the enzymatic activity of the acetyl-CoA synthetase (Acs) and glutamine synthetase (Gs). Furthermore, we compared the malonylation levels of the two-growth state to explore the potential effect of malonylation on the erythromycin biosynthesis. These findings expand our current knowledge of the actinomycetes malonylome and supplement the acylproteome databases of the whole bacteria. PMID:27090497

  4. Possibility of 2,4,5-triamino-6-hydroxypyrimidine as an intermediate in the pathway of riboflavin biosynthesis.

    Science.gov (United States)

    Nakajima, K; Yamada, Y; Mitsuda, H

    1985-01-01

    It was studied with resting cells of a high flavinogenic mold, Eremothecium ashbyii, whether or not 2,4,5-triamino-6-hydroxypyrimidine (THP) is an intermediate in the early pathway of riboflavin biosynthesis. A small amounts of THP strongly inhibited riboflavin formation in the resting cells, but the inhibition was effectively reversed by the added purines, except for adenine. Radioactive tracer experiments showed that the incorporation of the radioactivity from [2-14C]THP into riboflavin was negligible. The results obtained strongly suggest that THP is not an intermediate but a rigid inhibitor for riboflavin formation, and thus there is non salvage pathway of THP for the pathway of riboflavin biosynthesis in resting cells of E. ashbyii. PMID:4041122

  5. Characterization and modification of enzymes in the 2-ketoisovalerate biosynthesis pathway of Ralstonia eutropha H16

    Energy Technology Data Exchange (ETDEWEB)

    Lu, JN; Brigham, CJ; Plassmeier, JK; Sinskey, AJ

    2014-08-01

    2-Ketoisovalerate is an important cellular intermediate for the synthesis of branched-chain amino acids as well as other important molecules, such as pantothenate, coenzyme A, and glucosinolate. This ketoacid can also serve as a precursor molecule for the production of biofuels, pharmaceutical agents, and flavor agents in engineered organisms, such as the betaproteobacterium Ralstonia eutropha. The biosynthesis of 2-ketoisovalerate from pyruvate is carried out by three enzymes: acetohydroxyacid synthase (AHAS, encoded by ilvBH), acetohydroxyacid isomeroreductase (AHAIR, encoded by ilvC), and dihydroxyacid dehydratase (DHAD, encoded by ilvD). In this study, enzymatic activities and kinetic parameters were determined for each of the three R. eutropha enzymes as heterologously purified proteins. AHAS, which serves as a gatekeeper for the biosynthesis of all three branched-chain amino acids, demonstrated the tightest regulation through feedback inhibition by l-valine (IC50 = 1.2 mM), l-isoleucine (IC50 = 2.3 mM), and l-leucine (IC50 = 5.4 mM). Intermediates in the valine biosynthesis pathway also exhibit feedback inhibitory control of the AHAS enzyme. In addition, AHAS has a very weak affinity for pyruvate (K-M = 10.5 mu M) and is highly selective towards 2-ketobutyrate (R = 140) as a second substrate. AHAIR and DHAD are also inhibited by the branched-chain amino acids, although to a lesser extent when compared to AHAS. Experimental evolution and rational site-directed mutagenesis revealed mutants of the regulatory subunit of AHAS (IlvH) (N11S, T34I, A36V, T104S, N11F, G14E, and N29H), which, when reconstituted with wild-type IlvB, lead to AHAS having reduced valine, leucine, and isoleucine sensitivity. The study of the kinetics and inhibition mechanisms of R. eutropha AHAS, AHAIR, and DHAD has shed light on interactions between these enzymes and the products they produce; it, therefore, can be used to engineer R. eutropha strains with optimal production of 2

  6. A novel radio-tolerant astaxanthin-producing bacterium reveals a new astaxanthin derivative: astaxanthin dirhamnoside.

    Science.gov (United States)

    Asker, Dalal; Awad, Tarek S; Beppu, Teruhiko; Ueda, Kenji

    2012-01-01

    Astaxanthin is a red ketocarotenoid that exhibits extraordinary health-promoting activities such as antioxidant, anti-inflammatory, antitumor, and immune booster. The recent discovery of the beneficial roles of astaxanthin against many degenerative diseases such as cancers, heart diseases, and exercise-induced fatigue has raised its market demand as a nutraceutical and medicinal ingredient in aquaculture, food, and pharmaceutical industries. To satisfy the growing demand for this high-value nutraceuticals ingredient and consumer interest in natural products, many research efforts are being made to discover novel microbial producers with effective biotechnological production of astaxanthin. Using a rapid screening method based on 16S rRNA gene, and effective HPLC-Diodearray-MS methods for carotenoids analysis, we succeeded to isolate a unique astaxanthin-producing bacterium (strain TDMA-17(T)) that belongs to the family Sphingomonadaceae (Asker et al., Appl Microbiol Biotechnol 77: 383-392, 2007). In this chapter, we provide a detailed description of effective HPLC-Diodearray-MS methods for rapid analysis and identification of the carotenoids produced by strain TDMA-17(T). We also describe the methods of isolation and identification for a novel bacterial carotenoid (astaxanthin derivative), a major carotenoid that is produced by strain TDMA-17(T). Finally, we describe the polyphasic taxonomic analysis of strain TDMA-17(T) and the description of a novel species belonging to genus Sphingomonas. PMID:22623297

  7. Identification of additive, dominant, and epistatic variation conferred by key genes in cellulose biosynthesis pathway in Populus tomentosa

    OpenAIRE

    Du, Qingzhang; Tian, Jiaxing; Yang, Xiaohui; Pan, Wei; Xu, Baohua; Li, Bailian; Pär K Ingvarsson; Zhang, Deqiang

    2015-01-01

    Economically important traits in many species generally show polygenic, quantitative inheritance. The components of genetic variation (additive, dominant and epistatic effects) of these traits conferred by multiple genes in shared biological pathways remain to be defined. Here, we investigated 11 full-length genes in cellulose biosynthesis, on 10 growth and wood-property traits, within a population of 460 unrelated Populus tomentosa individuals, via multi-gene association. To validate positiv...

  8. Simultaneous production of triacylglycerol and high-value carotenoids by the astaxanthin-producing oleaginous green microalga Chlorella zofingiensis.

    Science.gov (United States)

    Liu, Jin; Mao, Xuemei; Zhou, Wenguang; Guarnieri, Michael T

    2016-08-01

    The production of lipids and astaxanthin, a high-value carotenoid, by Chlorella zofingiensis was investigated under different culture conditions. Comparative analysis revealed a good correlation between triacylglycerol (TAG) and astaxanthin accumulation in C. zofingiensis. Stress conditions promoted cell size and weight and induced the accumulation of neutral lipids, especially TAG and astaxanthin, with a concomitant decrease in membrane lipids. The highest contents of TAG and astaxanthin achieved were 387 and 4.89mgg(-1) dry weight, respectively. A semi-continuous culture strategy was developed to optimize the TAG and astaxanthin productivities, which reached 297 and 3.3mgL(-1)day(-1), respectively. Additionally, astaxanthin accumulation was enhanced by inhibiting de novo fatty acid biosynthesis. In summary, our study represents a pioneering work of utilizing Chlorella for the integrated production of lipids and high-value products and C. zofingiensis has great potential to be a promising production strain and serve as an emerging oleaginous model alga. PMID:27152772

  9. Astaxanthin diferulate as a bifunctional antioxidant

    DEFF Research Database (Denmark)

    Papa, T.B.R.; Pinho, V.D.; Nascimento, E.P. do; Santos, W.G.; Burtoloso, A.C.B.; Skibsted, Leif Horsfelt; Cardoso, D.R.

    2015-01-01

    Abstract Astaxanthin when esterified with ferulic acid is better singlet oxygen quencher with k2 = (1.58 ± 0.1) 10(10) L mol(- 1)s(- 1) in ethanol at 25°C compared with astaxanthin with k2 = (1.12 ± 0.01) 10(9) L mol(- 1)s(- 1). The ferulate moiety in the astaxanthin diester is a better radical s...

  10. A quinazoline-based HDAC inhibitor affects gene expression pathways involved in cholesterol biosynthesis and mevalonate in prostate cancer cells.

    Science.gov (United States)

    Lin, Z; Bishop, K S; Sutherland, H; Marlow, G; Murray, P; Denny, W A; Ferguson, L R

    2016-03-01

    Chronic inflammation can lead to the development of cancers and resolution of inflammation is an ongoing challenge. Inflammation can result from dysregulation of the epigenome and a number of compounds that modify the epigenome are in clinical use. In this study the anti-inflammatory and anti-cancer effects of a quinazoline epigenetic-modulator compound were determined in prostate cancer cell lines using a non-hypothesis driven transcriptomics strategy utilising the Affymetrix PrimeView® Human Gene Expression microarray. GATHER and IPA software were used to analyse the data and to provide information on significantly modified biological processes, pathways and networks. A number of genes were differentially expressed in both PC3 and DU145 prostate cancer cell lines. The top canonical pathways that frequently arose across both cell lines at a number of time points included cholesterol biosynthesis and metabolism, and the mevalonate pathway. Targeting of sterol and mevalonate pathways may be a powerful anticancer approach. PMID:26759180

  11. De Novo Transcriptome and Expression Profile Analysis to Reveal Genes and Pathways Potentially Involved in Cantharidin Biosynthesis in the Blister Beetle Mylabris cichorii.

    Science.gov (United States)

    Huang, Yi; Wang, Zhongkang; Zha, Shenfang; Wang, Yu; Jiang, Wei; Liao, Yufeng; Song, Zhangyong; Qi, Zhaoran; Yin, Youping

    2016-01-01

    The dried body of Mylabris cichorii is well-known Chinese traditional medicine. The sesquiterpenoid cantharidin, which is secreted mostly by adult male beetles, has recently been used as an anti-cancer drug. However, little is known about the mechanisms of cantharidin biosynthesis. Furthermore, there is currently no genomic or transcriptomic information for M. cichorii. In this study, we performed de novo assembly transcriptome of M. cichorii using the Illumina Hiseq2000. A single run produced 9.19 Gb of clean nucleotides comprising 29,247 sequences, including 23,739 annotated sequences (about 81%). We also constructed two expression profile libraries (20-25 day-old adult males and 20-25 day-old adult females) and discovered 2,465 significantly differentially-expressed genes. Putative genes and pathways involved in the biosynthesis of cantharidin were then characterized. We also found that cantharidin biosynthesis in M. cichorii might only occur via the mevalonate (MVA) pathway, not via the methylerythritol 4-phosphate/deoxyxylulose 5-phosphate (MEP/DOXP) pathway or a mixture of these. Besides, we considered that cantharidin biosynthesis might be related to the juvenile hormone (JH) biosynthesis or degradation. The results of transcriptome and expression profiling analysis provide a comprehensive sequence resource for M. cichorii that could facilitate the in-depth study of candidate genes and pathways involved in cantharidin biosynthesis, and may thus help to improve our understanding of the mechanisms of cantharidin biosynthesis in blister beetles. PMID:26752526

  12. 5-Aminolevulinic acid production in engineered Corynebacterium glutamicum via C5 biosynthesis pathway.

    Science.gov (United States)

    Ramzi, Ahmad Bazli; Hyeon, Jeong Eun; Kim, Seung Wook; Park, Chulhwan; Han, Sung Ok

    2015-12-01

    ALA (5-aminolevulinic acid) is an important intermediate in the synthesis of tetrapyrroles and the use of ALA has been gradually increasing in many fields, including medicine and agriculture. In this study, improved biological production of ALA in Corynebacterium glutamicum was achieved by overexpressing glutamate-initiated C5 pathway. For this purpose, copies of the glutamyl t-RNA reductase HemA from several bacteria were mutated by site-directed mutagenesis of which a HemA version from Salmonella typhimurium exhibited the highest ALA production. Cultivation of the HemA-expressing strain produced approximately 204 mg/L of ALA, while co-expression with HemL (glutamate-1-semialdehyde aminotransferase) increased ALA concentration to 457 mg/L, representing 11.6- and 25.9-fold increases over the control strain (17 mg/L of ALA). Further effects of metabolic perturbation were investigated, leading to penicillin addition that further improves ALA production to 584 mg/L. In an optimized flask fermentation, engineered C. glutamicum strains expressing the HemA and hemAL operon produced up to 1.1 and 2.2g/L ALA, respectively, under glutamate-producing conditions. The final yields represent 10.7- and 22.0-fold increases over the control strain (0.1g/L of ALA). From these findings, ALA biosynthesis from glucose was successfully demonstrated and this study is the first to report ALA overproduction in C. glutamicum via metabolic engineering. PMID:26453466

  13. Critical importance of the de novo pyrimidine biosynthesis pathway for Trypanosoma cruzi growth in the mammalian host cell cytoplasm

    International Nuclear Information System (INIS)

    Highlights: ► We established Trypanosoma cruzi lacking the gene for carbamoyl phosphate synthetase II. ► Disruption of the cpsII gene significantly reduced the growth of epimastigotes. ► In particular, the CPSII-null mutant severely retarded intracellular growth. ► The de novo pyrimidine pathway is critical for the parasite growth in the host cell. -- Abstract: The intracellular parasitic protist Trypanosoma cruzi is the causative agent of Chagas disease in Latin America. In general, pyrimidine nucleotides are supplied by both de novo biosynthesis and salvage pathways. While epimastigotes—an insect form—possess both activities, amastigotes—an intracellular replicating form of T. cruzi—are unable to mediate the uptake of pyrimidine. However, the requirement of de novo pyrimidine biosynthesis for parasite growth and survival has not yet been elucidated. Carbamoyl-phosphate synthetase II (CPSII) is the first and rate-limiting enzyme of the de novo biosynthetic pathway, and increased CPSII activity is associated with the rapid proliferation of tumor cells. In the present study, we showed that disruption of the T. cruzicpsII gene significantly reduced parasite growth. In particular, the growth of amastigotes lacking the cpsII gene was severely suppressed. Thus, the de novo pyrimidine pathway is important for proliferation of T. cruzi in the host cell cytoplasm and represents a promising target for chemotherapy against Chagas disease.

  14. Critical importance of the de novo pyrimidine biosynthesis pathway for Trypanosoma cruzi growth in the mammalian host cell cytoplasm

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Muneaki, E-mail: muneaki@juntendo.ac.jp [Department of Molecular and Cellular Parasitology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Morales, Jorge; Fukai, Yoshihisa; Suzuki, Shigeo; Takamiya, Shinzaburo; Tsubouchi, Akiko; Inoue, Syou [Department of Molecular and Cellular Parasitology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Inoue, Masayuki [Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Kita, Kiyoshi [Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Harada, Shigeharu [Department of Applied Biology, Graduate School of Science and Technology, Kyoto Institute of Technology, Sakyo-ku, Kyoto 606-8585 (Japan); Tanaka, Akiko [Systems and Structural Biology Center, RIKEN, Tsurumi, Yokohama 230-0045 (Japan); Aoki, Takashi [Department of Molecular and Cellular Parasitology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Nara, Takeshi, E-mail: tnara@juntendo.ac.jp [Department of Molecular and Cellular Parasitology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan)

    2012-01-20

    Highlights: Black-Right-Pointing-Pointer We established Trypanosoma cruzi lacking the gene for carbamoyl phosphate synthetase II. Black-Right-Pointing-Pointer Disruption of the cpsII gene significantly reduced the growth of epimastigotes. Black-Right-Pointing-Pointer In particular, the CPSII-null mutant severely retarded intracellular growth. Black-Right-Pointing-Pointer The de novo pyrimidine pathway is critical for the parasite growth in the host cell. -- Abstract: The intracellular parasitic protist Trypanosoma cruzi is the causative agent of Chagas disease in Latin America. In general, pyrimidine nucleotides are supplied by both de novo biosynthesis and salvage pathways. While epimastigotes-an insect form-possess both activities, amastigotes-an intracellular replicating form of T. cruzi-are unable to mediate the uptake of pyrimidine. However, the requirement of de novo pyrimidine biosynthesis for parasite growth and survival has not yet been elucidated. Carbamoyl-phosphate synthetase II (CPSII) is the first and rate-limiting enzyme of the de novo biosynthetic pathway, and increased CPSII activity is associated with the rapid proliferation of tumor cells. In the present study, we showed that disruption of the T. cruzicpsII gene significantly reduced parasite growth. In particular, the growth of amastigotes lacking the cpsII gene was severely suppressed. Thus, the de novo pyrimidine pathway is important for proliferation of T. cruzi in the host cell cytoplasm and represents a promising target for chemotherapy against Chagas disease.

  15. Absorption Spectra of Astaxanthin Aggregates

    OpenAIRE

    Olsina, Jan; Durchan, Milan; Minofar, Babak; Polivka, Tomas; Mancal, Tomas

    2012-01-01

    Carotenoids in hydrated polar solvents form aggregates characterized by dramatic changes in their absorption spectra with respect to monomers. Here we analyze absorption spectra of aggregates of the carotenoid astaxanthin in hydrated dimethylsulfoxide. Depending on water content, two types of aggregates were produced: H-aggregates with absorption maximum around 390 nm, and J-aggregates with red-shifted absorption band peaking at wavelengths >550 nm. The large shifts with respect to absorption...

  16. Carotenoid production and gene expression in an astaxanthin-overproducing Xanthophyllomyces dendrorhous mutant strain.

    Science.gov (United States)

    Castelblanco-Matiz, Lina M; Barbachano-Torres, Alejandra; Ponce-Noyola, Teresa; Ramos-Valdivia, Ana C; Cerda García-Rojas, Carlos M; Flores-Ortiz, César M; Barahona-Crisóstomo, Salvador K; Baeza-Cancino, Marcelo E; Alcaíno-Gorman, Jennifer; Cifuentes-Guzmán, Víctor H

    2015-12-01

    The primary carotenoid synthesized by Xanthophyllomyces dendrorhous is astaxanthin, which is used as a feed additive in aquaculture. Cell growth kinetics and carotenoid production were correlated with the mRNA levels of the idi, crtE, crtYB, crtI, crtS and crtR genes, and the changes in gene sequence between the wild-type and a carotenoid overproducer XR4 mutant strain were identified. At the late stationary phase, the total carotenoid content in XR4 was fivefold higher than that of the wild-type strain. Additionally, the mRNA levels of crtE and crtS increased during the XR4 growth and were three times higher than the wild-type strain in the late stationary phase. Moreover, the nucleotide sequences of crtYB, crtI and crtR exhibited differences between the strains. Both the higher crtE and crtS transcript levels and the crtYB, crtI and crtR mutations can, at least in part, act to up-regulate the carotenoid biosynthesis pathway in the XR4 strain. PMID:26377586

  17. Comparative transcriptome analysis of different chemotypes elucidates withanolide biosynthesis pathway from medicinal plant Withania somnifera.

    Science.gov (United States)

    Gupta, Parul; Goel, Ridhi; Agarwal, Aditya Vikram; Asif, Mehar Hasan; Sangwan, Neelam Singh; Sangwan, Rajender Singh; Trivedi, Prabodh Kumar

    2015-01-01

    Withania somnifera is one of the most valuable medicinal plants synthesizing secondary metabolites known as withanolides. Despite pharmaceutical importance, limited information is available about the biosynthesis of withanolides. Chemo-profiling of leaf and root tissues of Withania suggest differences in the content and/or nature of withanolides in different chemotypes. To identify genes involved in chemotype and/or tissue-specific withanolide biosynthesis, we established transcriptomes of leaf and root tissues of distinct chemotypes. Genes encoding enzymes for intermediate steps of terpenoid backbone biosynthesis with their alternatively spliced forms and paralogous have been identified. Analysis suggests differential expression of large number genes among leaf and root tissues of different chemotypes. Study also identified differentially expressing transcripts encoding cytochrome P450s, glycosyltransferases, methyltransferases and transcription factors which might be involved in chemodiversity in Withania. Virus induced gene silencing of the sterol ∆7-reductase (WsDWF5) involved in the synthesis of 24-methylene cholesterol, withanolide backbone, suggests role of this enzyme in biosynthesis of withanolides. Information generated, in this study, provides a rich resource for functional analysis of withanolide-specific genes to elucidate chemotype- as well as tissue-specific withanolide biosynthesis. This genomic resource will also help in development of new tools for functional genomics and breeding in Withania. PMID:26688389

  18. Pigmenting efficacy of astaxanthin fed to rainbow trout Oncorhynchus mykiss: Effect of dietary astaxanthin and lipid sources

    OpenAIRE

    Choubert, Georges; Mendes-Pinto, Maria Manuela; Morais, Rui

    2006-01-01

    The aim of the present experiment was to investigate the effect of two different dietary types of oil (fish oil (FI) and olive oil (OL)) on the pigmenting efficacy of astaxanthin from the green micro-algae Haematococcus pluvialis (ALG) (total amount of carotenoid pigments 32 mg kg− 1 on a dry weight basis of which astaxanthin accounted for 98.6%) and from the synthetic astaxanthin (AST) in terms of astaxanthin serum concentration, induced muscle colour, and astaxanthin muscle retention in rai...

  19. Auxin Biosynthesis

    OpenAIRE

    Zhao, Yunde

    2014-01-01

    lndole-3-acetic acid (IAA), the most important natural auxin in plants, is mainly synthesized from the amino acid tryptophan (Trp). Recent genetic and biochemical studies in Arabidopsis have unambiguously established the first complete Trp-dependent auxin biosynthesis pathway. The first chemical step of auxin biosynthesis is the removal of the amino group from Trp by the TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS (TAA) family of transaminases to generate indole-3-pyruvate (IPA). IPA then unde...

  20. A Novel Pathway for Sesquiterpene Biosynthesis from Z,Z-Farnesyl Pyrophosphate in the Wild Tomato Solanum habrochaites[W

    Science.gov (United States)

    Sallaud, Christophe; Rontein, Denis; Onillon, Sandrine; Jabès, Françoise; Duffé, Philippe; Giacalone, Cécile; Thoraval, Samuel; Escoffier, Camille; Herbette, Gaëtan; Leonhardt, Nathalie; Causse, Mathilde; Tissier, Alain

    2009-01-01

    In the wild tomato Solanum habrochaites, the Sst2 locus on chromosome 8 is responsible for the biosynthesis of several class II sesquiterpene olefins by glandular trichomes. Analysis of a trichome-specific EST collection from S. habrochaites revealed two candidate genes for the synthesis of Sst2-associated sesquiterpenes. zFPS encodes a protein with homology to Z-isoprenyl pyrophosphate synthases and SBS (for Santalene and Bergamotene Synthase) encodes a terpene synthase with homology to kaurene synthases. Both genes were found to cosegregate with the Sst2 locus. Recombinant zFPS protein catalyzed the synthesis of Z,Z-FPP from isopentenylpyrophosphate (IPP) and dimethylallylpyrophosphate (DMAPP), while coincubation of zFPS and SBS with the same substrates yielded a mixture of olefins identical to the Sst2-associated sesquiterpenes, including (+)-α-santalene, (+)-endo-β-bergamotene, and (−)-endo-α-bergamotene. In addition, headspace analysis of tobacco (Nicotiana sylvestris) plants expressing zFPS and SBS in glandular trichomes afforded the same mix of sesquiterpenes. Each of these proteins contains a putative plastid targeting sequence that mediates transport of a fused green fluorescent protein to the chloroplasts, suggesting that the biosynthesis of these sesquiterpenes uses IPP and DMAPP from the plastidic DXP pathway. These results provide novel insights into sesquiterpene biosynthesis and have general implications concerning sesquiterpene engineering in plants. PMID:19155349

  1. Characterization of the GDP-D-mannose biosynthesis pathway in Coxiella burnetii: the initial steps for GDP-β-D-virenose biosynthesis.

    Science.gov (United States)

    Narasaki, Craig T; Mertens, Katja; Samuel, James E

    2011-01-01

    Coxiella burnetii, the etiologic agent of human Q fever, is a gram-negative and naturally obligate intracellular bacterium. The O-specific polysaccharide chain (O-PS) of the lipopolysaccharide (LPS) of C. burnetii is considered a heteropolymer of the two unusual sugars β-D-virenose and dihydrohydroxystreptose and mannose. We hypothesize that GDP-D-mannose is a metabolic intermediate to GDP-β-D-virenose. GDP-D-mannose is synthesized from fructose-6-phosphate in 3 successive reactions; Isomerization to mannose-6-phosphate catalyzed by a phosphomannose isomerase (PMI), followed by conversion to mannose-1-phosphate mediated by a phosphomannomutase (PMM) and addition of GDP by a GDP-mannose pyrophosphorylase (GMP). GDP-D-mannose is then likely converted to GDP-6-deoxy-D-lyxo-hex-4-ulopyranose (GDP-Sug), a virenose intermediate, by a GDP-mannose-4,6-dehydratase (GMD). To test the validity of this pathway in C. burnetii, three open reading frames (CBU0671, CBU0294 and CBU0689) annotated as bifunctional type II PMI, as PMM or GMD were functionally characterized by complementation of corresponding E. coli mutant strains and in enzymatic assays. CBU0671, failed to complement an Escherichia coli manA (PMM) mutant strain. However, complementation of an E. coli manC (GMP) mutant strain restored capsular polysaccharide biosynthesis. CBU0294 complemented a Pseudomonas aeruginosa algC (GMP) mutant strain and showed phosphoglucomutase activity (PGM) in a pgm E. coli mutant strain. Despite the inability to complement a manA mutant, recombinant C. burnetii PMI protein showed PMM enzymatic activity in biochemical assays. CBU0689 showed dehydratase activity and determined kinetic parameters were consistent with previously reported data from other organisms. These results show the biological function of three C. burnetii LPS biosynthesis enzymes required for the formation of GDP-D-mannose and GDP-Sug. A fundamental understanding of C. burnetii genes that encode PMI, PMM and GMP is

  2. Characterization of the GDP-D-mannose biosynthesis pathway in Coxiella burnetii: the initial steps for GDP-β-D-virenose biosynthesis.

    Directory of Open Access Journals (Sweden)

    Craig T Narasaki

    Full Text Available Coxiella burnetii, the etiologic agent of human Q fever, is a gram-negative and naturally obligate intracellular bacterium. The O-specific polysaccharide chain (O-PS of the lipopolysaccharide (LPS of C. burnetii is considered a heteropolymer of the two unusual sugars β-D-virenose and dihydrohydroxystreptose and mannose. We hypothesize that GDP-D-mannose is a metabolic intermediate to GDP-β-D-virenose. GDP-D-mannose is synthesized from fructose-6-phosphate in 3 successive reactions; Isomerization to mannose-6-phosphate catalyzed by a phosphomannose isomerase (PMI, followed by conversion to mannose-1-phosphate mediated by a phosphomannomutase (PMM and addition of GDP by a GDP-mannose pyrophosphorylase (GMP. GDP-D-mannose is then likely converted to GDP-6-deoxy-D-lyxo-hex-4-ulopyranose (GDP-Sug, a virenose intermediate, by a GDP-mannose-4,6-dehydratase (GMD. To test the validity of this pathway in C. burnetii, three open reading frames (CBU0671, CBU0294 and CBU0689 annotated as bifunctional type II PMI, as PMM or GMD were functionally characterized by complementation of corresponding E. coli mutant strains and in enzymatic assays. CBU0671, failed to complement an Escherichia coli manA (PMM mutant strain. However, complementation of an E. coli manC (GMP mutant strain restored capsular polysaccharide biosynthesis. CBU0294 complemented a Pseudomonas aeruginosa algC (GMP mutant strain and showed phosphoglucomutase activity (PGM in a pgm E. coli mutant strain. Despite the inability to complement a manA mutant, recombinant C. burnetii PMI protein showed PMM enzymatic activity in biochemical assays. CBU0689 showed dehydratase activity and determined kinetic parameters were consistent with previously reported data from other organisms. These results show the biological function of three C. burnetii LPS biosynthesis enzymes required for the formation of GDP-D-mannose and GDP-Sug. A fundamental understanding of C. burnetii genes that encode PMI, PMM and

  3. The putrescine biosynthesis pathway in Lactococcus lactis is transcriptionally regulated by carbon catabolic repression, mediated by CcpA.

    Science.gov (United States)

    Linares, Daniel M; del Río, Beatriz; Ladero, Victor; Redruello, Begoña; Martín, María Cruz; Fernández, María; Alvarez, Miguel A

    2013-07-01

    Lactococcus lactis is the lactic acid bacterium most widely used by the dairy industry as a starter for the manufacture of fermented products such as cheese and buttermilk. However, some strains produce putrescine from agmatine via the agmatine deiminase (AGDI) pathway. The proteins involved in this pathway, including those necessary for agmatine uptake and conversion into putrescine, are encoded by the aguB, aguD, aguA and aguC genes, which together form an operon. This paper reports the mechanism of regulation of putrescine biosynthesis in L. lactis. It is shown that the aguBDAC operon, which contains a cre site at the promoter of aguB (the first gene of the operon), is transcriptionally regulated by carbon catabolic repression (CCR) mediated by the catabolite control protein CcpA. PMID:23688550

  4. Astaxanthin uptake in domestic dogs and cats

    OpenAIRE

    Massimino Stefan; Hayek Michael G; Mathison Bridget D; Kim Hong; Park Jean; Reinhart Gregory A; Chew Boon P

    2010-01-01

    Abstract Background Research on the uptake and transport of astaxanthin is lacking in most species. We studied the uptake of astaxanthin by plasma, lipoproteins and leukocytes in domestic dogs and cats. Methods Mature female Beagle dogs (18 to 19 mo old; 11 to 14 kg BW) were dosed orally with 0, 0.1, 0.5, 2.5, 10 or 40 mg astaxanthin and blood taken at 0, 3, 6, 9, 12, 18 and 24 h post-administration (n = 8/treatment). Similarly, mature domestic short hair cats (12 mo old; 3 to 3.5 kg body wei...

  5. Characterization of the Fucosylation Pathway in the Biosynthesis of Glycopeptidolipids from Mycobacterium avium Complex▿

    OpenAIRE

    Miyamoto, Yuji; Mukai, Tetsu; Maeda, Yumi; Nakata, Noboru; Kai, Masanori; Naka, Takashi; Yano, Ikuya; Makino, Masahiko

    2007-01-01

    The cell envelopes of several species of nontuberculous mycobacteria, including the Mycobacterium avium complex, contain glycopeptidolipids (GPLs) as major glycolipid components. GPLs are highly antigenic surface molecules, and their variant oligosaccharides define each serotype of the M. avium complex. In the oligosaccharide portion of GPLs, the fucose residue is one of the major sugar moieties, but its biosynthesis remains unclear. To elucidate it, we focused on the 5.0-kb chromosomal regio...

  6. Excited-state dynamics of astaxanthin aggregates

    Czech Academy of Sciences Publication Activity Database

    Fuciman, M.; Durchan, Milan; Šlouf, V.; Kesan, G.; Polívka, Tomáš

    2013-01-01

    Roč. 568, č. 1 (2013), s. 21-25. ISSN 0009-2614 Institutional support: RVO:60077344 Keywords : astaxanthin * aggregates * excited states Subject RIV: BO - Biophysics Impact factor: 1.991, year: 2013

  7. Mutations in four glycosyl hydrolases reveal a highly coordinated pathway for rhodopsin biosynthesis and N-glycan trimming in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Erica E Rosenbaum

    2014-05-01

    Full Text Available As newly synthesized glycoproteins move through the secretory pathway, the asparagine-linked glycan (N-glycan undergoes extensive modifications involving the sequential removal and addition of sugar residues. These modifications are critical for the proper assembly, quality control and transport of glycoproteins during biosynthesis. The importance of N-glycosylation is illustrated by a growing list of diseases that result from defects in the biosynthesis and processing of N-linked glycans. The major rhodopsin in Drosophila melanogaster photoreceptors, Rh1, is highly unique among glycoproteins, as the N-glycan appears to be completely removed during Rh1 biosynthesis and maturation. However, much of the deglycosylation pathway for Rh1 remains unknown. To elucidate the key steps in Rh1 deglycosylation in vivo, we characterized mutant alleles of four Drosophila glycosyl hydrolases, namely α-mannosidase-II (α-Man-II, α-mannosidase-IIb (α-Man-IIb, a β-N-acetylglucosaminidase called fused lobes (Fdl, and hexosaminidase 1 (Hexo1. We have demonstrated that these four enzymes play essential and unique roles in a highly coordinated pathway for oligosaccharide trimming during Rh1 biosynthesis. Our results reveal that α-Man-II and α-Man-IIb are not isozymes like their mammalian counterparts, but rather function at distinct stages in Rh1 maturation. Also of significance, our results indicate that Hexo1 has a biosynthetic role in N-glycan processing during Rh1 maturation. This is unexpected given that in humans, the hexosaminidases are typically lysosomal enzymes involved in N-glycan catabolism with no known roles in protein biosynthesis. Here, we present a genetic dissection of glycoprotein processing in Drosophila and unveil key steps in N-glycan trimming during Rh1 biosynthesis. Taken together, our results provide fundamental advances towards understanding the complex and highly regulated pathway of N-glycosylation in vivo and reveal novel insights

  8. Astaxanthin dynamics in Baltic Sea mesozooplankton communities

    Science.gov (United States)

    Snoeijs, Pauline; Häubner, Norbert

    2014-01-01

    The red pigment astaxanthin is a powerful antioxidant, which occurs in eggs and body tissues of crustaceans and fish. It is produced by crustaceans from algal carotenoids. In a two-year field study we assessed natural concentrations and dynamics of astaxanthin in mesozooplankton communities in the brackish Baltic Sea area. Astaxanthin levels varied between 0.37 and 36 ng L- 1. They increased with salinity along the Baltic Sea gradient and were linked to zooplankton biomass and phytoplankton community composition. Astaxanthin concentrations showed typical seasonal patterns and varied from 0.2 to 5.1 ng ind- 1, 0.2 to 3.4 ng (μg C)- 1 and 6 to 100 ng mm- 3. These concentrations were inversely related to water temperature and strongly linked to zooplankton community composition. Communities dominated by the calanoid copepods Temora longicornis, Pseudocalanus acuspes and Eurytemora spp. generally held the highest concentrations. With increasing cladocerans:copepods biomass ratios community astaxanthin concentrations decreased and with higher relative biomass of Acartia spp. the proportion of astaxanthin diesters decreased. Diesters prevailed in the cold season and they are thought to improve the antioxidant protection of storage lipids during winter. Climate change causes higher temperature and lower salinity in the Baltic Sea proper. This modifies zooplankton community composition, but not necessarily into a community with lower concentrations of astaxanthin since T. longicornis (high concentrations) has been reported to increase with higher temperature. However, decreased astaxanthin production in the ecosystem is expected if a basin-wide increase in the cladocerans:copepods biomass ratios would occur with further climate change.

  9. Astaxanthin in Cardiovascular Health and Disease

    Directory of Open Access Journals (Sweden)

    Robert G. Fassett

    2012-02-01

    Full Text Available Oxidative stress and inflammation are established processes contributing to cardiovascular disease caused by atherosclerosis. However, antioxidant therapies tested in cardiovascular disease such as vitamin E, C and β-carotene have proved unsuccessful at reducing cardiovascular events and mortality. Although these outcomes may reflect limitations in trial design, new, more potent antioxidant therapies are being pursued. Astaxanthin, a carotenoid found in microalgae, fungi, complex plants, seafood, flamingos and quail is one such agent. It has antioxidant and anti-inflammatory effects. Limited, short duration and small sample size studies have assessed the effects of astaxanthin on oxidative stress and inflammation biomarkers and have investigated bioavailability and safety. So far no significant adverse events have been observed and biomarkers of oxidative stress and inflammation are attenuated with astaxanthin supplementation. Experimental investigations in a range of species using a cardiac ischaemia-reperfusion model demonstrated cardiac muscle preservation when astaxanthin is administered either orally or intravenously prior to the induction of ischaemia. Human clinical cardiovascular studies using astaxanthin therapy have not yet been reported. On the basis of the promising results of experimental cardiovascular studies and the physicochemical and antioxidant properties and safety profile of astaxanthin, clinical trials should be undertaken.

  10. Thiol Redox Sensitivity of Two Key Enzymes of Heme Biosynthesis and Pentose Phosphate Pathways: Uroporphyrinogen Decarboxylase and Transketolase

    Directory of Open Access Journals (Sweden)

    Brian McDonagh

    2013-01-01

    Full Text Available Uroporphyrinogen decarboxylase (Hem12p and transketolase (Tkl1p are key mediators of two critical processes within the cell, heme biosynthesis, and the nonoxidative part of the pentose phosphate pathway (PPP. The redox properties of both Hem12p and Tkl1p from Saccharomyces cerevisiae were investigated using proteomic techniques (SRM and label-free quantification and biochemical assays in cell extracts and in vitro with recombinant proteins. The in vivo analysis revealed an increase in oxidized Cys-peptides in the absence of Grx2p, and also after treatment with H2O2 in the case of Tkl1p, without corresponding changes in total protein, demonstrating a true redox response. Out of three detectable Cys residues in Hem12p, only the conserved residue Cys52 could be modified by glutathione and efficiently deglutathionylated by Grx2p, suggesting a possible redox control mechanism for heme biosynthesis. On the other hand, Tkl1p activity was sensitive to thiol redox modification and although Cys622 could be glutathionylated to a limited extent, it was not a natural substrate of Grx2p. The human orthologues of both enzymes have been involved in certain cancers and possess Cys residues equivalent to those identified as redox sensitive in yeast. The possible implication for redox regulation in the context of tumour progression is put forward.

  11. In silico and in vitro Studies on Begomovirus Induced Andrographolide Biosynthesis Pathway in Andrographis Paniculata for Combating Inflammation and Cancer.

    Science.gov (United States)

    Khan, Asifa; Sharma, Pooja; Khan, Feroz; Ajayakumar, P V; Shanker, Karuna; Samad, Abdul

    2016-07-01

    Andrographolide and neoandrographolide are major bioactive molecules of Andrographis paniculata, a well-known medicinal plant. These molecules exhibited varying degrees of anti-inflammatory and anticancer activities in-vitro and in-vivo. Role of begomovirus protein C2/TrAP in biosynthesis of andrographolide was identified through molecular modeling, docking and predicted results were substantiated by in vitro studies. Homology molecular modeling and molecular docking were performed to study the binding conformations and different bonding behaviors, in order to reveal the possible mechanism of action behind higher accumulation of andrographolide. It was concluded that C2/TrAP inhibit the activation of SNF1-Related Protein Kinase-1 (SnRK1) in terpenoid pathway and removes the negative regulation of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) by SnRK1, leading to higher accumulation of andrographolide and neoandrographolide in begomovirus infected plants. The binding site residues of SnRK1 docked with C2/TrAP were found to be associated with ATP binding site, substrate binding site and activation loop. Predicted results were also validated by HPTLC. This study provides important insights into understanding the role of viral protein in altering the regulation of biosynthesis of andrographolide and could be used in future research to develop biomimetic methods for increasing the production of such phytometabolites having anti-cancerous and anti-inflammatory properties. PMID:27492239

  12. Free Radical Scavenging and Cellular Antioxidant Properties of Astaxanthin

    OpenAIRE

    Janina Dose; Seiichi Matsugo; Haruka Yokokawa; Yutaro Koshida; Shigetoshi Okazaki; Ulrike Seidel; Manfred Eggersdorfer; Gerald Rimbach; Tuba Esatbeyoglu

    2016-01-01

    Astaxanthin is a coloring agent which is used as a feed additive in aquaculture nutrition. Recently, potential health benefits of astaxanthin have been discussed which may be partly related to its free radical scavenging and antioxidant properties. Our electron spin resonance (ESR) and spin trapping data suggest that synthetic astaxanthin is a potent free radical scavenger in terms of diphenylpicryl-hydrazyl (DPPH) and galvinoxyl free radicals. Furthermore, astaxanthin dose-dependently quench...

  13. Regulation of myo-inositol biosynthesis by p53-ISYNA1 pathway.

    Science.gov (United States)

    Koguchi, Tomoyuki; Tanikawa, Chizu; Mori, Jinichi; Kojima, Yoshiyuki; Matsuda, Koichi

    2016-06-01

    In response to various cellular stresses, p53 exerts its tumor suppressive effects such as apoptosis, cell cycle arrest, and senescence through the induction of its target genes. Recently, p53 was shown to control cellular homeostasis by regulating energy metabolism, glycolysis, antioxidant effect, and autophagy. However, its function in inositol synthesis was not reported. Through a microarray screening, we found that five genes related with myo-inositol metabolism were induced by p53. DNA damage enhanced intracellular myo-inositol content in HCT116 p53+/+ cells, but not in HCT116 p53-/- cells. We also indicated that inositol 3-phosphate synthase (ISYNA1) which encodes an enzyme essential for myo-inositol biosynthesis as a direct target of p53. Activated p53 regulated ISYNA1 expression through p53 response element in the seventh exon. Ectopic ISYNA1 expression increased myo-inositol levels in the cells and suppressed tumor cell growth. Knockdown of ISYNA1 caused resistance to adriamycin treatment, demonstrating the role of ISYNA1 in p53-mediated growth suppression. Furthermore, ISYNA1 expression was significantly associated with p53 mutation in bladder, breast cancer, head and neck squamous cell carcinoma, lung squamous cell carcinoma, and pancreatic adenocarcinoma. Our findings revealed a novel role of p53 in myo-inositol biosynthesis which could be a potential therapeutic target. PMID:27035231

  14. Osmotic regulation and tissue localization of the myo-inositol biosynthesis pathway in tilapia (Oreochromis mossambicus) larvae.

    Science.gov (United States)

    Sacchi, Romina; Gardell, Alison M; Chang, Nicole; Kültz, Dietmar

    2014-10-01

    The myo-inositol biosynthesis (MIB) pathway converts glucose-6-phosphate to the compatible osmolyte myo-inositol, which protects cells from salinity stress. We exposed tilapia larvae just after yolk sac resorption to various hypersaline environments and recorded robust induction of the enzymes that constitute the MIB pathway, myo-inositol-phosphate synthase (MIPS), and inositol monophosphatase 1 (IMPA1). Strong up-regulation of these enzymes is evident at both mRNA (quantitative real-time PCR) and protein (densitometric analysis of Western blots) levels. The highest level of induction of these enzymes occurs at the highest salinity that larvae were exposed to (90 ppt). Less severe salinity stress causes a proportionately reduced induction of the MIB pathway. Two distinct MIPS mRNA variants are present in tilapia larvae and both are induced at comparable levels for all the salinity challenges tested (34, 70, and 90 ppt). Immunohistochemical localization of IMPA1 protein in sagittal sections of salinity stressed and control larvae identified tissues that are particularly potent in inducing the MIB pathway. These tissues include the skin (epidermis), gills, eye (ciliary epithelium) and heart. In particular, the epidermis directly facing the external milieu showed a very strong induction of IMPA1 immunoreactivity. IMPA1 induction in response to salinity stress was not observed in other tissues suggesting that tilapia larvae may also utilize compatible organic osmolytes other than solely myo-inositol for osmoprotection. We conclude that the MIB pathway plays an important role in protecting multiple (but not all) tissues of tilapia larvae from hyperosmotic salinity stress. PMID:25045088

  15. 21 CFR 73.37 - Astaxanthin dimethyl-disuccinate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Astaxanthin dimethyl-disuccinate. 73.37 Section 73... LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Foods § 73.37 Astaxanthin dimethyl-disuccinate. (a) Identity. (1) The color additive astaxanthin dimethyldisuccinate is...

  16. Optimization of the IPP precursor supply for the production of lycopene, decaprenoxanthin and astaxanthin by Corynebacterium glutamicum

    Directory of Open Access Journals (Sweden)

    Sabine A.E. Heider

    2014-08-01

    Full Text Available The biotechnologically relevant bacterium C. glutamicum, currently used for the million ton-scale production of amino acids for the food and feed industries, is pigmented due to synthesis of the rare cyclic C50 carotenoid decaprenoxanthin and its glucosides. The precursors of carotenoid biosynthesis, isopenthenyl pyrophosphate (IPP and its isomer dimethylallyl pyrophosphate (DMAPP, are synthesized in this organism via the methylerythritol phosphate (MEP or non-mevalonate pathway. Terminal pathway engineering in recombinant C. glutamicum permitted the production of various nonnative C50 and C40 carotenoids. Here, the role of engineering isoprenoid precursor supply for lycopene production by C. glutamicum was characterized. Overexpression of dxs encoding the enzyme that catalyzes the first committed step of the MEP-pathway by chromosomal promoter exchange in a prophage-cured, genome-reduced C. glutamicum strain improved lycopene formation. Similarly, an increased IPP supply was achieved by chromosomal integration of two artificial operons comprising MEP pathway genes under the control of a constitutive promoter. Combined overexpression of dxs and the other six MEP pathways genes in C. glutamicum strain LYC3-MEP was not synergistic with respect to improving lycopene accumulation. Based on C. glutamicum strain LYC3-MEP astaxanthin could be produced in the mg per g cell dry weight range when the endogenous genes crtE, crtB and crtI for conversion of geranylgeranyl pyrophosphate to lycopene were coexpressed with the genes for lycopene cyclase and β-carotene hydroxylase from Pantoea ananatis and carotene C(4 oxygenase from Brevundimonas aurantiaca.

  17. Differential selection on carotenoid biosynthesis genes as a function of gene position in the metabolic pathway: a study on the carrot and dicots.

    Directory of Open Access Journals (Sweden)

    Jérémy Clotault

    Full Text Available BACKGROUND: Selection of genes involved in metabolic pathways could target them differently depending on the position of genes in the pathway and on their role in controlling metabolic fluxes. This hypothesis was tested in the carotenoid biosynthesis pathway using population genetics and phylogenetics. METHODOLOGY/PRINCIPAL FINDINGS: Evolutionary rates of seven genes distributed along the carotenoid biosynthesis pathway, IPI, PDS, CRTISO, LCYB, LCYE, CHXE and ZEP, were compared in seven dicot taxa. A survey of deviations from neutrality expectations at these genes was also undertaken in cultivated carrot (Daucus carota subsp. sativus, a species that has been intensely bred for carotenoid pattern diversification in its root during its cultivation history. Parts of sequences of these genes were obtained from 46 individuals representing a wide diversity of cultivated carrots. Downstream genes exhibited higher deviations from neutral expectations than upstream genes. Comparisons of synonymous and nonsynonymous substitution rates between genes among dicots revealed greater constraints on upstream genes than on downstream genes. An excess of intermediate frequency polymorphisms, high nucleotide diversity and/or high differentiation of CRTISO, LCYB1 and LCYE in cultivated carrot suggest that balancing selection may have targeted genes acting centrally in the pathway. CONCLUSIONS/SIGNIFICANCE: Our results are consistent with relaxed constraints on downstream genes and selection targeting the central enzymes of the carotenoid biosynthesis pathway during carrot breeding history.

  18. Expanding the modular ester fermentative pathways for combinatorial biosynthesis of esters from volatile organic acids.

    Science.gov (United States)

    Layton, Donovan S; Trinh, Cong T

    2016-08-01

    Volatile organic acids are byproducts of fermentative metabolism, for example, anaerobic digestion of lignocellulosic biomass or organic wastes, and are often times undesired inhibiting cell growth and reducing directed formation of the desired products. Here, we devised a general framework for upgrading these volatile organic acids to high-value esters that can be used as flavors, fragrances, solvents, and biofuels. This framework employs the acid-to-ester modules, consisting of an AAT (alcohol acyltransferase) plus ACT (acyl CoA transferase) submodule and an alcohol submodule, for co-fermentation of sugars and organic acids to acyl CoAs and alcohols to form a combinatorial library of esters. By assembling these modules with the engineered Escherichia coli modular chassis cell, we developed microbial manufacturing platforms to perform the following functions: (i) rapid in vivo screening of novel AATs for their catalytic activities; (ii) expanding combinatorial biosynthesis of unique fermentative esters; and (iii) upgrading volatile organic acids to esters using single or mixed cell cultures. To demonstrate this framework, we screened for a set of five unique and divergent AATs from multiple species, and were able to determine their novel activities as well as produce a library of 12 out of the 13 expected esters from co-fermentation of sugars and (C2-C6) volatile organic acids. We envision the developed framework to be valuable for in vivo characterization of a repertoire of not-well-characterized natural AATs, expanding the combinatorial biosynthesis of fermentative esters, and upgrading volatile organic acids to high-value esters. Biotechnol. Bioeng. 2016;113: 1764-1776. © 2016 Wiley Periodicals, Inc. PMID:26853081

  19. Mimicking a natural pathway for de novo biosynthesis: natural vanillin production from accessible carbon sources

    OpenAIRE

    Jun Ni; Fei Tao; Huaiqing Du; Ping Xu

    2015-01-01

    Plant secondary metabolites have been attracting people’s attention for centuries, due to their potentials; however, their production is still difficult and costly. The rich diversity of microbes and microbial genome sequence data provide unprecedented gene resources that enable to develop efficient artificial pathways in microorganisms. Here, by mimicking a natural pathway of plants using microbial genes, a new metabolic route was developed in E. coli for the synthesis of vanillin, the most ...

  20. Genome Mining for antibiotics biosynthesis pathways with antiSMASH 3

    DEFF Research Database (Denmark)

    Weber, Tilmann; Kim, Hyun Uk; Blin, Kai;

    2014-01-01

    Microorganisms are the most important source of natural products with antimicrobial or antitumor activity. These natural products are the main source for anti-­‐infectives; 80% of antibiotics currently in medical use are derived from this class of compounds. In the past, functional screenings......://antismash.secondarymetabolites.org). antiSMASH3 currently is the most comprehensive automated genome mining platform for natural product biosynthetic pathways. It automatically screens genomic data of bacteria and fungi for the presence of 24 different types of secondary metabolite biosynthetic pathways. For different classes of secondary...

  1. Mimicking a natural pathway for de novo biosynthesis: natural vanillin production from accessible carbon sources.

    Science.gov (United States)

    Ni, Jun; Tao, Fei; Du, Huaiqing; Xu, Ping

    2015-01-01

    Plant secondary metabolites have been attracting people's attention for centuries, due to their potentials; however, their production is still difficult and costly. The rich diversity of microbes and microbial genome sequence data provide unprecedented gene resources that enable to develop efficient artificial pathways in microorganisms. Here, by mimicking a natural pathway of plants using microbial genes, a new metabolic route was developed in E. coli for the synthesis of vanillin, the most widely used flavoring agent. A series of factors were systematically investigated for raising production, including efficiency and suitability of genes, gene dosage, and culture media. The metabolically engineered strain produced 97.2 mg/L vanillin from l-tyrosine, 19.3 mg/L from glucose, 13.3 mg/L from xylose and 24.7 mg/L from glycerol. These results show that the metabolic route enables production of natural vanillin from low-cost substrates, suggesting that it is a good strategy to mimick natural pathways for artificial pathway design. PMID:26329726

  2. Mutations in Escherichia coli aceE and ribB Genes Allow Survival of Strains Defective in the First Step of the Isoprenoid Biosynthesis Pathway

    OpenAIRE

    Jordi Perez-Gil; Eva Maria Uros; Susanna Sauret-Güeto; Maria Lois, L.; James Kirby; Minobu Nishimoto; Baidoo, Edward E. K.; Jay D Keasling; Albert Boronat; Manuel Rodriguez-Concepcion

    2012-01-01

    A functional 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway is required for isoprenoid biosynthesis and hence survival in Escherichia coli and most other bacteria. In the first two steps of the pathway, MEP is produced from the central metabolic intermediates pyruvate and glyceraldehyde 3-phosphate via 1-deoxy-D-xylulose 5-phosphate (DXP) by the activity of the enzymes DXP synthase (DXS) and DXP reductoisomerase (DXR). Because the MEP pathway is absent from humans, it was proposed as a pro...

  3. Excited-state dynamics of astaxanthin aggregates

    Science.gov (United States)

    Fuciman, Marcel; Durchan, Milan; Šlouf, Václav; Keşan, Gürkan; Polívka, Tomáš

    2013-05-01

    Astaxanthin forms three types of aggregates in hydrated dimethyl sulfoxide (DMSO). In DMSO/water ratio of 1:1, a red-shifted J-aggregate with maximum at 570 nm is generated, while a ratio of 1:9 produces blue-shifted H-aggregates with peaks at 386 nm (H1) and 460 nm (H2). Monomeric astaxanthin in DMSO has an S1 lifetime of 5.3 ps, but a long-lived (33 ps) S∗ signal was also identified. Aggregation changes the S1 lifetimes to 17 ps (H1), 30 ps (H2), and 14 ps (J). Triplet state of astaxanthin, most likely generated via singlet homofission, was observed in H1 and H2 aggregates.

  4. Differential expression of carotenogenic genes, associated changes on astaxanthin production and photosynthesis features induced by JA in H. pluvialis.

    Directory of Open Access Journals (Sweden)

    Zhengquan Gao

    Full Text Available Haematococcus pluvialis is an organism that under certain conditions can produce astaxanthin, an economically important carotenoid. In this study, the transcriptional expression patterns of eight carotenogenic genes of H. pluvialis in response to jasmonic acid (JA were evaluated using real-time PCR. Astaxanthin accumulation action and photosynthesis flourescence were monitored at the same time. The results showed all eight genes exhibited higher transcriptional expression significantly under JA treatments. JA25 (25 mg/L induction had greater effect (>10-fold up-regulation on the transcriptional expression of pds, crtR-B and lyc than on ipi-1, ipi-2, psy, bkt2, and crtO. JA50 (50 mg/L treatment had greater impact on the transcriptional expression of ipi-1, ipi-2, psy, crtR-B and crtO than on pds, lyc and bkt2. Astaxanthin biosynthesis in the presence of JA appeared to be up-regulated mainly by psy, pds, crtR-B, lyc, bkt2 and crtO at the transcriptional level and ipi-1, ipi-2 at both transcriptional and post-transcriptional levels. Under JA induction, the photosynthetic efficiency [Y (II] and the maximum quantum efficiency of PS II (Fv/Fm decreased significantly, but the non-photochemical quenching of chlorophyll fluorescence (NPQ increased drastically with the accumulation of astaxanthin.

  5. Regulatory networks, genes and glycerophospholipid biosynthesis pathway in schistosomiasis: a systems biology view for pharmacological intervention.

    Science.gov (United States)

    Shinde, Sonali; Mol, Milsee; Singh, Shailza

    2014-10-25

    Understanding network topology through embracing the global dynamical regulation of genes in an active state space rather than traditional one-gene-one trait approach facilitates the rational drug development process. Schistosomiasis, a neglected tropical disease, has glycerophospholipids as abundant molecules present on its surface. Lack of effective clinical solutions to treat pathogens encourages us to carry out systems-level studies that could contribute to the development of an effective therapy. Development of a strategy for identifying drug targets by combined genome-scale metabolic network and essentiality analyses through in silico approaches provides tantalizing opportunity to investigate the role of protein/substrate metabolism. A genome-scale metabolic network model reconstruction represents choline-phosphate cytidyltransferase as the rate limiting enzyme and regulates the rate of phosphatidylcholine (PC) biosynthesis. The uptake of choline was regulated by choline concentration, promoting the regulation of phosphocholine synthesis. In Schistosoma, the change in developmental stage could result from the availability of choline, hampering its developmental cycle. There are no structural reports for this protein. In order to inhibit the activity of choline-phosphate cytidyltransferase (CCT), it was modeled by homology modeling using 1COZ as the template from Bacillus subtilis. The transition-state stabilization and catalytic residues were mapped as 'HXGH' and 'RTEGISTT' motif. CCT catalyzes the formation of CDP-choline from phosphocholine in which nucleotidyltransferase adds CTP to phosphocholine. The presence of phosphocholine permits the parasite to survive in an immunologically hostile environment. This feature endeavors development of an inhibitor specific for cytidyltransferase in Schistosoma. Flavonolignans were used to inhibit this activity in which hydnowightin showed the highest affinity as compared to miltefosine. PMID:25149020

  6. Efektifitas Astaxanthin Oral disertai Gel Astaxanthin Dibandingkan dengan Astaxanthin Oral disertai Krim Triple Combination (Hidrokuinon 4%, Tretinoin 0,05%, Fluosinolon Asetonid 0,01%) dalam Pengobatan Melasma

    OpenAIRE

    Lubis, Faridah Israwaty

    2011-01-01

    Background : Melasma is a common acquired symmetrical hypermelanosis that occurs on sun-exposed facial areas. Melasma is frequently observed among women. Many modalities of treatment are available but none is satisfactory. Aim : To compare the efficacy and safety of oral astaxanthin combined with astaxanthin gel and oral astaxanthin combined with triple combination cream in the treatment of melasma. Subject and methods : A double blind, randomize, clinical trial design study was condu...

  7. EG-01EPIGENETIC INACTIVATION OF ARGININE BIOSYNTHESIS PATHWAY IN PAEDIATRIC HIGH GRADE GLIOMA

    OpenAIRE

    Channathodiyil, Prasanna; Kardooni, Hoda; Khozoie, Combiz; Nelofer, Syed; Darling, John; Morris, Mark; Warr, Tracy

    2014-01-01

    Aberrant cellular metabolism contributes significantly to the growth and proliferation of several tumour types. Identification of genes that control critical metabolic pathways is a major factor in the development of novel therapies that target metabolic defects in tumour cells. Our aim is to identify such genes in paediatric high grade glioma that are altered due to promoter hyper-methylation of cytosine residues in CpG dinucleotides. Genome wide DNA methylation profiling using Illumina infi...

  8. The sequence diversity and expression among genes of the folic acid biosynthesis pathway in industrial Saccharomyces strains.

    Science.gov (United States)

    Goncerzewicz, Anna; Misiewicz, Anna

    2015-01-01

    Folic acid is an important vitamin in human nutrition and its deficiency in pregnant women's diets results in neural tube defects and other neurological damage to the fetus. Additionally, DNA synthesis, cell division and intestinal absorption are inhibited in case of adults. Since this discovery, governments and health organizations worldwide have made recommendations concerning folic acid supplementation of food for women planning to become pregnant. In many countries this has led to the introduction of fortifications, where synthetic folic acid is added to flour. It is known that Saccharomyces strains (brewing and bakers' yeast) are one of the main producers of folic acid and they can be used as a natural source of this vitamin. Proper selection of the most efficient strains may enhance the folate content in bread, fermented vegetables, dairy products and beer by 100% and may be used in the food industry. The objective of this study was to select the optimal producing yeast strain by determining the differences in nucleotide sequences in the FOL2, FOL3 and DFR1 genes of folic acid biosynthesis pathway. The Multitemperature Single Strand Conformation Polymorphism (MSSCP) method and further nucleotide sequencing for selected strains were applied to indicate SNPs in selected gene fragments. The RT qPCR technique was also applied to examine relative expression of the FOL3 gene. Furthermore, this is the first time ever that industrial yeast strains were analysed regarding genes of the folic acid biosynthesis pathway. It was observed that a correlation exists between the folic acid amount produced by industrial yeast strains and changes in the nucleotide sequence of adequate genes. The most significant changes occur in the DFR1 gene, mostly in the first part, which causes major protein structure modifications in KKP 232, KKP 222 and KKP 277 strains. Our study shows that the large amount of SNP contributes to impairment of the selected enzymes and S. cerevisiae and S

  9. Functional balance between enzymes in malonyl-CoA pathway for 3-hydroxypropionate biosynthesis.

    Science.gov (United States)

    Liu, Changshui; Ding, Yamei; Zhang, Rubing; Liu, Huizhou; Xian, Mo; Zhao, Guang

    2016-03-01

    3-Hydroxypropionate (3HP) is an important platform chemical, and four 3HP biosynthetic routes were reported, in which the malonyl-CoA pathway has some expected advantages but presented the lowest 3HP yield. Here, we demonstrated that this low yield was caused by a serious functional imbalance between MCR-C and MCR-N proteins, responsible for the two-step reduction of malonyl-CoA to 3HP. Then we minimized the enzyme activity imbalance by directed evolution of rate-limiting enzyme MCR-C and fine tuning of MCR-N expression level. Combined with culture conditions optimization, our engineering approaches increased the 3HP titer 270-fold, from 0.15 g/L to 40.6 g/L, representing the highest 3HP production via malonyl-CoA pathway so far. This study not only significantly improved the 3HP productivity of recombinant Escherichia coli strain, but also proved the importance of metabolic balance in a multistep biosynthetic pathway, which should be always considered in any metabolic engineering study. PMID:26791242

  10. A positive feedback pathway of estrogen biosynthesis in breast cancer cells is contained by resveratrol

    International Nuclear Information System (INIS)

    Cytochrome P450 (CYP) 19 enzyme or aromatase catalyses the rate-determining step of estrogen synthesis. The transcriptional control of CYP19 gene is highly specific in different cell types, for instance, Promoter I.3/II is commonly used for regulation in breast cancer cells. Recently, a positive feedback pathway for estrogen synthesis has been identified in ERα expressing SK-BR-3 cells. CYP19 mRNA abundance and activity are increased in this pathway and the promoter usage is switched from Promoter I.3/II to I.1 through a non-genomic process. In the present study, effect of the phytocompound resveratrol on this Promoter I.1-controlled expression of aromatase was investigated. Results indicated that resveratrol reduced the estradiol-induced mRNA abundance in SK-BR-3 cells expressing ERα. Luciferase reporter gene assays revealed that resveratrol could also repress the transcriptional control dictated by Promoter I.1. Since the ERE-driven luciferase activity was not repressed by resveratrol, the nuclear events of estrogen were unlikely to be suppressed by resveratrol. Instead the phytochemical reduced the amount of ERK activated by estradiol, which could be the pathway responsible for Promoter I.1 transactivation and the induced CYP19 expression. The present study illustrated that resveratrol impeded the non-genomic induction of estrogen on CYP19

  11. Propiconazole-enhanced hepatic cell proliferation is associated with dysregulation of the cholesterol biosynthesis pathway leading to activation of Erk1/2 through Ras farnesylation

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, Lynea A.; Moore, Tanya; Nesnow, Stephen, E-mail: nesnow.stephen@epa.gov

    2012-04-15

    Propiconazole is a mouse hepatotumorigenic fungicide designed to inhibit CYP51, a key enzyme in the biosynthesis of ergosterol in fungi and is widely used in agriculture to prevent fungal growth. Metabolomic studies in mice revealed that propiconazole increased levels of hepatic cholesterol metabolites and bile acids, and transcriptomic studies revealed that genes within the cholesterol biosynthesis, cholesterol metabolism and bile acid biosyntheses pathways were up-regulated. Hepatic cell proliferation was also increased by propiconazole. AML12 immortalized hepatocytes were used to study propiconazole's effects on cell proliferation focusing on the dysregulation of cholesterol biosynthesis and resulting effects on Ras farnesylation and Erk1/2 activation as a primary pathway. Mevalonate, a key intermediate in the cholesterol biosynthesis pathway, increases cell proliferation in several cancer cell lines and tumors in vivo and serves as the precursor for isoprenoids (e.g. farnesyl pyrophosphate) which are crucial in the farnesylation of the Ras protein by farnesyl transferase. Farnesylation targets Ras to the cell membrane where it is involved in signal transduction, including the mitogen-activated protein kinase (MAPK) pathway. In our studies, mevalonic acid lactone (MVAL), a source of mevalonic acid, increased cell proliferation in AML12 cells which was reduced by farnesyl transferase inhibitors (L-744,832 or manumycin) or simvastatin, an HMG-CoA reductase inhibitor, indicating that this cell system responded to alterations in the cholesterol biosynthesis pathway. Cell proliferation in AML12 cells was increased by propiconazole which was reversed by co-incubation with L-744,832 or simvastatin. Increasing concentrations of exogenous cholesterol muted the proliferative effects of propiconazole and the inhibitory effects of L-733,832, results ascribed to reduced stimulation of the endogenous cholesterol biosynthesis pathway. Western blot analysis of subcellular

  12. Astaxanthin, canthaxanthin and astaxanthin esters in the copepod Acartia bifilosa (Copepoda, Calanoida) during ontogenetic development

    OpenAIRE

    Maria £otocka; Ewa Styczynska-Jurewicz

    2001-01-01

    The contents of astaxanthin, canthaxanthin and astaxanthin esters were studied in natural populations of the copepod Acartia bifilosa from the Pomeranian Bay and Gulf of Gdansk in the southern Baltic Sea. Samples dominated by any one of three developmental groups: (1) nauplii, (2) copepodids I-III and (3) copepodids IV-V and adults of Acartia bifilosa were analysed by means of high performance liquid chromatography (HPLC). As ontogenetic development progressed, significant changes occurre...

  13. Astaxanthin, canthaxanthin and astaxanthin esters in the copepod Acartia bifilosa (Copepoda, Calanoida during ontogenetic development

    Directory of Open Access Journals (Sweden)

    Maria £otocka

    2001-12-01

    Full Text Available The contents of astaxanthin, canthaxanthin and astaxanthin esters were studied in natural populations of the copepod Acartia bifilosa from the Pomeranian Bay and Gulf of Gdansk in the southern Baltic Sea. Samples dominated by any one of three developmental groups: (1 nauplii, (2 copepodids I-III and (3 copepodids IV-V and adults of Acartia bifilosa were analysed by means of high performance liquid chromatography (HPLC. As ontogenetic development progressed, significant changes occurred in the proportion of particular pigments in the total pigment pool of the various developmental groups. Astaxanthin and canthaxanthin occurred in all the groups, the former being clearly dominant. However, an increasing percentage of astaxanthin esters was recorded in the copepodids I-III, and even more in the copepodids IV-V and adults group. Most probably, astaxanthin is the main pigment active in copepod lipid metabolism. Carotenoid pigments in copepods very likely act as efficient free-electron quenchers and may be involved as antioxidants in rapid lipid metabolism. The exogenously feeding stages (late nauplii and copepodids transform plant carotenoids taken from food and are evidently capable of metabolising astaxanthin by esterification and further degradation. It is emphasised that, according to literature data, astaxanthin esters may have an even higher quenching ability. It is suggested that crustacean carotenoid pigments, with their electron donor-acceptor abilities, may replace oxygen in peroxidation processes connected with lipid metabolism. The consequences of such a physiological role of astaxanthin for present-day estimations of energy balances in zooplankton communities are mentioned.

  14. Flavonoid biosynthesis: 'new' functions for an 'old' pathway

    International Nuclear Information System (INIS)

    Flavonoids are important plant secondary metabolites that have been extensively studied using genetic, biochemical and molecular approaches. Recent analyses have focused on our understanding of the role of flavonoids in such well-established processes as plant-microbe interactions and protection against ultraviolet (UV) light, and have also uncovered a previously unsuspected role in male fertility. These studies demonstrate the utility of flavonoid structures for a broad range of activities, and also highlight the value of the flavonoid pathway as a paradigm for studying the evolution of plant metabolism

  15. Effect of red cyst cell inoculation and iron(II) supplementation on autotrophic astaxanthin production by Haematococcus pluvialis under outdoor summer conditions.

    Science.gov (United States)

    Hong, Min-Eui; Choi, Yoon Young; Sim, Sang Jun

    2016-01-20

    The negative effect of heat stress on the autotrophic astaxanthin production by Haematococcus pluvialis has been observed during outdoor culture in summer. Under the summer conditions, the proliferation of vegetative cells was highly halted in the green stage and the inducibility in the biosynthesis of astaxanthin was partly hindered in the red stage. Herein, under outdoor summer conditions in which variations of the diurnal temperature occur, heat-stress-driven inefficient vegetative growth of H. pluvialis was highly improved by inoculating the red cyst cells; thereby, maintaining relatively moderate intracellular carotenoid levels in the green stage. Subsequently, a remarkably enhanced astaxanthin titer was successfully obtained by supplementing 50 μM iron(II) to induce the heat stress-driven Haber-Weiss reaction in the red stage. As a result, the productivity of astaxanthin in the cells cultured under summer temperature conditions (23.4-33.5 °C) using the two methods of red cell (cyst) inoculation and the iron(Fe(2+)) supplementation was increased by 147% up to 5.53 mg/L day compared with that of the cells cultured under spring temperature conditions (17.5-27.3 °C). Our technical solutions will definitely improve the annual natural astaxanthin productivity in H. pluvialis in locations confronted by hot summer weather, particularly in large-scale closed photobioreactor systems. PMID:26630998

  16. Evidence for a universal pathway of abscisic acid biosynthesis in higher plants from sup 18 O incorporation patterns

    Energy Technology Data Exchange (ETDEWEB)

    Zeevaart, J.A.D.; Heath, T.G.; Gage, D.A. (Michigan State University, East Lansing (USA))

    1989-12-01

    Previous labeling studies of abscisic acid (ABA) with {sup 18}O{sub 2} have been mainly conducted with water-stressed leaves. In this study, {sup 18}O incorporation into ABA of stressed leaves of various species was compared with {sup 18}O labeling of ABA of turgid leaves and of fruit tissue in different stages of ripening. In stressed leaves of all six species investigated, avocado (Persea americana), barley (Hordeum vulgare), bean (Phaseolus vulgaris), cocklebur (Xanthium strumarium), spinach (Spinacia oleracea), and tobacco (Nicotiana tabacum), {sup 18}O was most abundant in the carboxyl group, whereas incorporation of a second and third {sup 18}O in the oxygen atoms on the ring of ABA was much less prominent after 24 h in {sup 18}O{sub 2}. ABA from turgid bean leaves showed significant {sup 18}O incorporation, again with highest {sup 18}O enrichment in the carboxyl group. On the basis of {sup 18}O-labeling patterns observed in ABA from different tissues it is concluded that, despite variations in precusor pool sizes and intermediate turnover rates, there is a universal pathway of ABA biosynthesis in higher plants which involves cleavage of a larger precursor molecule, presumably an oxygenated carotenoid.

  17. A multienzyme complex channels substrates and electrons through acetyl-CoA and methane biosynthesis pathways in Methanosarcina.

    Directory of Open Access Journals (Sweden)

    Dillon J Lieber

    Full Text Available Multienzyme complexes catalyze important metabolic reactions in many organisms, but little is known about the complexes involved in biological methane production (methanogenesis. A crosslinking-mass spectrometry (XL-MS strategy was employed to identify proteins associated with coenzyme M-coenzyme B heterodisulfide reductase (Hdr, an essential enzyme in all methane-producing archaea (methanogens. In Methanosarcina acetivorans, Hdr forms a multienzyme complex with acetyl-CoA decarbonylase synthase (ACDS, and F420-dependent methylene-H4MPT reductase (Mer. ACDS is essential for production of acetyl-CoA during growth on methanol, or for methanogenesis from acetate, whereas Mer is essential for methanogenesis from all substrates. Existence of a Hdr:ACDS:Mer complex is consistent with growth phenotypes of ACDS and Mer mutant strains in which the complex samples the redox status of electron carriers and directs carbon flux to acetyl-CoA or methanogenesis. We propose the Hdr:ACDS:Mer complex comprises a special class of multienzyme redox complex which functions as a "biological router" that physically links methanogenesis and acetyl-CoA biosynthesis pathways.

  18. Evidence for a universal pathway of abscisic acid biosynthesis in higher plants from 18O incorporation patterns

    International Nuclear Information System (INIS)

    Previous labeling studies of abscisic acid (ABA) with 18O2 have been mainly conducted with water-stressed leaves. In this study, 18O incorporation into ABA of stressed leaves of various species was compared with 18O labeling of ABA of turgid leaves and of fruit tissue in different stages of ripening. In stressed leaves of all six species investigated, avocado (Persea americana), barley (Hordeum vulgare), bean (Phaseolus vulgaris), cocklebur (Xanthium strumarium), spinach (Spinacia oleracea), and tobacco (Nicotiana tabacum), 18O was most abundant in the carboxyl group, whereas incorporation of a second and third 18O in the oxygen atoms on the ring of ABA was much less prominent after 24 h in 18O2. ABA from turgid bean leaves showed significant 18O incorporation, again with highest 18O enrichment in the carboxyl group. On the basis of 18O-labeling patterns observed in ABA from different tissues it is concluded that, despite variations in precusor pool sizes and intermediate turnover rates, there is a universal pathway of ABA biosynthesis in higher plants which involves cleavage of a larger precursor molecule, presumably an oxygenated carotenoid

  19. Amino acids attenuate insulin action on gluconeogenesis and promote fatty acid biosynthesis via mTORC1 signaling pathway in trout hepatocytes

    OpenAIRE

    Dai, Wei Wei; Panserat, Stephane; Plagnes- Juan, Elisabeth; Seiliez, Iban; Skiba-Cassy, Sandrine

    2015-01-01

    Background/Aims: Carnivores exhibit poor utilization of dietary carbohydrates and glucose intolerant phenotypes, yet it remains unclear what are the causal factors and underlying mechanisms. We aimed to evaluate excessive amino acids (AAs)-induced effects on insulin signaling, fatty acid biosynthesis and glucose metabolism in rainbow trout and determine the potential involvement of mTORC1 and p38 MAPK pathway. Methods: We stimulated trout primary hepatocytes with different AA levels and emplo...

  20. PapR6, a Putative Atypical Response Regulator, Functions as a Pathway-Specific Activator of Pristinamycin II Biosynthesis in Streptomyces pristinaespiralis

    OpenAIRE

    Dun, Junling; Zhao, Yawei; Zheng, Guosong; Zhu, Hong; Ruan, Lijun; Wang, Wenfang; Ge, Mei; Jiang, Weihong; Lu, Yinhua

    2014-01-01

    There are up to seven regulatory genes in the pristinamycin biosynthetic gene cluster of Streptomyces pristinaespiralis, which infers a complicated regulation mechanism for pristinamycin production. In this study, we revealed that PapR6, a putative atypical response regulator, acts as a pathway-specific activator of pristinamycin II (PII) biosynthesis. Deletion of the papR6 gene resulted in significantly reduced PII production, and its overexpression led to increased PII formation, compared t...

  1. Free Radical Scavenging and Cellular Antioxidant Properties of Astaxanthin.

    Science.gov (United States)

    Dose, Janina; Matsugo, Seiichi; Yokokawa, Haruka; Koshida, Yutaro; Okazaki, Shigetoshi; Seidel, Ulrike; Eggersdorfer, Manfred; Rimbach, Gerald; Esatbeyoglu, Tuba

    2016-01-01

    Astaxanthin is a coloring agent which is used as a feed additive in aquaculture nutrition. Recently, potential health benefits of astaxanthin have been discussed which may be partly related to its free radical scavenging and antioxidant properties. Our electron spin resonance (ESR) and spin trapping data suggest that synthetic astaxanthin is a potent free radical scavenger in terms of diphenylpicryl-hydrazyl (DPPH) and galvinoxyl free radicals. Furthermore, astaxanthin dose-dependently quenched singlet oxygen as determined by photon counting. In addition to free radical scavenging and singlet oxygen quenching properties, astaxanthin induced the antioxidant enzyme paroxoanase-1, enhanced glutathione concentrations and prevented lipid peroxidation in cultured hepatocytes. Present results suggest that, beyond its coloring properties, synthetic astaxanthin exhibits free radical scavenging, singlet oxygen quenching, and antioxidant activities which could probably positively affect animal and human health. PMID:26784174

  2. Free Radical Scavenging and Cellular Antioxidant Properties of Astaxanthin

    Directory of Open Access Journals (Sweden)

    Janina Dose

    2016-01-01

    Full Text Available Astaxanthin is a coloring agent which is used as a feed additive in aquaculture nutrition. Recently, potential health benefits of astaxanthin have been discussed which may be partly related to its free radical scavenging and antioxidant properties. Our electron spin resonance (ESR and spin trapping data suggest that synthetic astaxanthin is a potent free radical scavenger in terms of diphenylpicryl-hydrazyl (DPPH and galvinoxyl free radicals. Furthermore, astaxanthin dose-dependently quenched singlet oxygen as determined by photon counting. In addition to free radical scavenging and singlet oxygen quenching properties, astaxanthin induced the antioxidant enzyme paroxoanase-1, enhanced glutathione concentrations and prevented lipid peroxidation in cultured hepatocytes. Present results suggest that, beyond its coloring properties, synthetic astaxanthin exhibits free radical scavenging, singlet oxygen quenching, and antioxidant activities which could probably positively affect animal and human health.

  3. Recovery of astaxanthin from seafood wastewater utilizing fish scales waste.

    Science.gov (United States)

    Stepnowski, P; Olafsson, G; Helgason, H; Jastorff, B

    2004-01-01

    The paper presents basic data on astaxanthin adsorption from fisheries wastewater to fish scales. This process has been proposed to be applicable in fisheries and shrimp waste management [Helgason, Recovery of compounds using a natural adsorbent, Patent WO 01/77230, 2001]. The innovative feature of the method is the application of a solid waste (fish scales) as a natural adsorbent for a carotenoid pigment (astaxanthin) from the seafood industry wastewater. The model investigations were performed with pure synthetic carotenoids to exclude the role of matrix in which astaxanthin is present in the wastewater. Under the experimental conditions used, the maximum loading capacity of astaxanthin onto the scales is 360 mg kg(-1) dry wt. Studies of the thus formed value added product indicated that drying causes significant loss of astaxanthin activity. Due to the effective filtration characteristics of the studied sorption material, we suggest the scale/astaxanthin sorption process to be suitable for treatment of wastewater from different industries. PMID:14575754

  4. Multispectral Image Analysis for Robust Prediction of Astaxanthin Coating

    OpenAIRE

    Ljungqvist, Martin Georg; Frosch, Stina; Nielsen, Michael Engelbrecht; Ersbøll, Bjarne Kjær

    2013-01-01

    The aim of this study was to investigate the possibility of predicting the type and concentration level of astaxanthin coating of aquaculture feed pellets using multispectral image analysis. We used both natural and synthetic astaxanthin, and we used several different concentration levels of synthetic astaxanthin in combination with four different recipes of feed pellets. We used a VideometerLab with 20 spectral bands in the range of 385-1050 nm. We used linear discriminant analysis and spars...

  5. Anxiolytic potential of astaxanthin on experimental animal model

    OpenAIRE

    Rekha Mehani; Vijay Kumar Yadav; Rajnish Sankadia

    2016-01-01

    Background: Astaxanthin is a naturally occurring carotenoid found in nature primarily in marine organisms. Carotenoids are well known for their therapeutic benefits in the aging process and various diseases, because of their antioxidant properties. Additionally, astaxanthin has well-documented anti-inflammatory and immune-stimulating effects. It is a known fact that oxidative stress is associated with depression, anxiety, and related psychiatric disorders. Astaxanthin may also reduce oxidativ...

  6. Effects of astaxanthin on antioxidation in human aqueous humor

    OpenAIRE

    Hashimoto, Hirotaka; Arai, Kiyomi; Hayashi, Shimmin; Okamoto, Hiroyuki; Takahashi, Jiro; Chikuda, Makoto; Obara, Yoshitaka

    2013-01-01

    We evaluated the antioxidative effects of astaxanthin through the changes in superoxide scavenging activity, levels of hydrogen peroxide and total hydroperoxides in human aqueous humor. The study subjects were 35 patients who underwent bilateral cataract surgery on one side before and the other side after intake of astaxanthin (6 mg/day for 2 weeks). Their aqueous humor was taken during the surgery and subjected to measurements of the three parameters. After astaxanthin intake, the superoxide...

  7. Astaxanthin: A Potential Therapeutic Agent in Cardiovascular Disease

    OpenAIRE

    Fassett, Robert G; Coombes, Jeff S

    2011-01-01

    Astaxanthin is a xanthophyll carotenoid present in microalgae, fungi, complex plants, seafood, flamingos and quail. It is an antioxidant with anti-inflammatory properties and as such has potential as a therapeutic agent in atherosclerotic cardiovascular disease. Synthetic forms of astaxanthin have been manufactured. The safety, bioavailability and effects of astaxanthin on oxidative stress and inflammation that have relevance to the pathophysiology of atherosclerotic cardiovascular disease, h...

  8. Nitric oxide mediates the fungal elicitor-induced Taxol biosynthesis of Taxus chinensis suspension cells through the reactive oxygen species-dependent and-independent signal pathways

    Institute of Scientific and Technical Information of China (English)

    XU Maojun; DONG Jufang

    2006-01-01

    pathways. Moreover, the results of our work show that the elicitor- and nitric oxide-induced Taxol biosynthesis is inhibited by catalase, indicating that H2O2 from the oxidative burst might be the signal molecule involved in induced Taxol production of T. chinensis cells.

  9. Nitric oxide mediates the fungal elicitor-induced puerarin biosynthesis in Pueraria thomsonii Benth. suspension cells through a salicylic acid (SA)-dependent and a jasmonic acid (JA)-dependent signal pathway

    Institute of Scientific and Technical Information of China (English)

    XU Maojun; DONG Jufang; ZHU Muyuan

    2006-01-01

    Nitric oxide (NO) has emerged as a key signaling molecule in plant secondary metabolite biosynthesis recently. In order to investigate the molecular basis of NO signaling in elicitor-induced secondary metabolite biosynthesis of plant cells, we determined the contents of NO, salicylic acid (SA), jasmonic acid (JA), and puerarin in Pueraria thomsonii Benth. suspension cells treated with the elicitors prepared from cell walls of Penicillium citrinum. The results showed that the fungal elicitor induced NO burst, SA accumulation and puerarin production of P. thomsonii Benth. cells. The elicitor-induced SA accumulation and puerarin production was suppressed by nitric oxide specific scavenger cPITO, indicating that NO was essential for elicitor-induced SA and puerarin biosynthesis in P. thomsonii Benth. cells. In transgenic NahG P. thomsonii Benth. cells, the fungal elicitor also induced puerarin biosynthesis, NO burst, and JA accumulation, though the SA biosynthesis was impaired. The elicitor-induced JA accumulation in transgenic cells was blocked by cPITO, which suggested that JA acted downstream of NO and its biosynthesis was controlled by NO. External application of NO via its donor sodium nitroprusside (SNP) enhanced puerarin biosynthesis in transgenic NahG P. thomsonii Benth. cells, and the NO-triggered puerarin biosynthesis was suppressed by JA inhibitors IBU and NDGA, which indicated that NO induced puerarin production through a JA-dependent signal pathway in the transgenic cells. Exogenous application of SA suppressed the elicitor-induced JA biosynthesis and reversed the inhibition of IBU and NDGA on elicitor-induced puerarin accumulation in transgenic cells, which indicated that SA inhibited JA biosynthesis in the cells and that SA might be used as a substitute for JA to mediate the elicitor- and NO-induced puerarin biosynthesis. It was, therefore, concluded that NO might mediate the elicitor-induced puerarin biosynthesis through SA- and JA-dependent signal

  10. De novo assembly and transcriptome analysis of the rubber tree (Hevea brasiliensis and SNP markers development for rubber biosynthesis pathways.

    Directory of Open Access Journals (Sweden)

    Camila Campos Mantello

    Full Text Available Hevea brasiliensis (Willd. Ex Adr. Juss. Muell.-Arg. is the primary source of natural rubber that is native to the Amazon rainforest. The singular properties of natural rubber make it superior to and competitive with synthetic rubber for use in several applications. Here, we performed RNA sequencing (RNA-seq of H. brasiliensis bark on the Illumina GAIIx platform, which generated 179,326,804 raw reads on the Illumina GAIIx platform. A total of 50,384 contigs that were over 400 bp in size were obtained and subjected to further analyses. A similarity search against the non-redundant (nr protein database returned 32,018 (63% positive BLASTx hits. The transcriptome analysis was annotated using the clusters of orthologous groups (COG, gene ontology (GO, Kyoto Encyclopedia of Genes and Genomes (KEGG, and Pfam databases. A search for putative molecular marker was performed to identify simple sequence repeats (SSRs and single nucleotide polymorphisms (SNPs. In total, 17,927 SSRs and 404,114 SNPs were detected. Finally, we selected sequences that were identified as belonging to the mevalonate (MVA and 2-C-methyl-D-erythritol 4-phosphate (MEP pathways, which are involved in rubber biosynthesis, to validate the SNP markers. A total of 78 SNPs were validated in 36 genotypes of H. brasiliensis. This new dataset represents a powerful information source for rubber tree bark genes and will be an important tool for the development of microsatellites and SNP markers for use in future genetic analyses such as genetic linkage mapping, quantitative trait loci identification, investigations of linkage disequilibrium and marker-assisted selection.

  11. Astaxanthin synthesis by Xanthophyllomyces dendrorhous DSM 5626 and its astaxanthin overproducing mutants on xylose media under diferent illumination

    OpenAIRE

    Barbara Stachowiak

    2014-01-01

    Background. Astaxanthin is the most important and expensive carotenoid pigment used in aquaculture. Its commercial attractiveness is also related with its antioxidant potential. XanthophyUomyces dendrorhous yeast is considered to be promising for commercial production of astaxanthin. The aim of this study was to investigate the possibility of the growth and astaxanthin production by X. dendrorhous strains 011 media containing xylose under different illumination. Material and method...

  12. The glycoinositol phospholipids of Leishmania mexicana promastigotes. Evidence for the presence of three distinct pathways of glycolipid biosynthesis.

    Science.gov (United States)

    McConville, M J; Collidge, T A; Ferguson, M A; Schneider, P

    1993-07-25

    was highly enriched for C24:0 or C26:0 alkyl chains. These data suggest that L. mexicana promastigotes contain three distinct pathways of GPI biosynthesis. The possibility that the distinct alkyl chain compositions of the different GPI glycolipids reflects the subcellular compartmentalization of different GPI biosynthetic pathways is discussed. PMID:8340385

  13. Nonlinear optics of astaxanthin thin films

    Science.gov (United States)

    Esser, A.; Fisch, Herbert; Haas, Karl-Heinz; Haedicke, E.; Paust, J.; Schrof, Wolfgang; Ticktin, Anton

    1993-02-01

    Carotinoids exhibit large nonlinear optical properties due to their extended (pi) -electron system. Compared to other polyenes which show a broad distribution of conjugation lengths, carotinoids exhibit a well defined molecular structure, i.e. a well defined conjugation length. Therefore the carotinoid molecules can serve as model compounds to study the relationship between structure and nonlinear optical properties. In this paper the synthesis of four astaxanthins with C-numbers ranging from 30 to 60, their preparation into thin films, wavelength dispersive Third Harmonic Generation (THG) measurements and some molecular modelling calculations will be presented. Resonant (chi) (3) values reach 1.2(DOT)10-10 esu for C60 astaxanthin. In the nonresonant regime a figure of merit (chi) (3)/(alpha) of several 10-13 esu-cm is demonstrated.

  14. Astaxanthin in Cardiovascular Health and Disease

    OpenAIRE

    Fassett, Robert G; Coombes, Jeff S

    2012-01-01

    Oxidative stress and inflammation are established processes contributing to cardiovascular disease caused by atherosclerosis. However, antioxidant therapies tested in cardiovascular disease such as vitamin E, C and β-carotene have proved unsuccessful at reducing cardiovascular events and mortality. Although these outcomes may reflect limitations in trial design, new, more potent antioxidant therapies are being pursued. Astaxanthin, a carotenoid found in microalgae, fungi, complex plants, seaf...

  15. Influence of astaxanthin, emulsifier and organic phase concentration on physicochemical properties of astaxanthin nanodispersions

    OpenAIRE

    Anarjan, Navideh; Nehdi, Imededdine Arbi; Tan, Chin Ping

    2013-01-01

    Background The emulsification-evaporation method was used to prepare astaxanthin nanodispersions using a three-component emulsifier system composed of Tween 20, sodium caseinate and gum Arabic. Using Response-surface methodology (RSM), we studied the main and interaction effects of the major emulsion components, namely, astaxanthin concentration (0.02–0.38 wt %, x1), emulsifier concentration (0.2–3.8 wt %, x2) and organic phase (dichloromethane) concentration (2–38 wt %, x3) on nanodispersion...

  16. Spectrally resolved femtosecond photon echo spectroscopy of astaxanthin

    Science.gov (United States)

    Kumar, Ajitesh; Karthick Kumar, S. K.; Gupta, Aditya; Goswami, Debabrata

    2011-08-01

    We have studied the coherence and population dynamics of Astaxanthin solution in methanol and acetonitrile by spectrally resolving their photon echo signals. Our experiments indicate that methanol has a much stronger interaction with the ultrafast dynamics of Astaxanthin in comparison to that of acetonitrile.

  17. Spectrally Resolved Femtosecond Photon Echo Spectroscopy of Astaxanthin

    OpenAIRE

    Kumar, Ajitesh; Kumar, S. K. Karthick; Gupta, Aditya; Goswami, Debabrata

    2011-01-01

    We have studied the coherence and population dynamics of Astaxanthin solution in methanol and acetonitrile by spectrally resolving their photon echo signals. Our experiments indicate that methanol has a much stronger interaction with the ultrafast dynamics of Astaxanthin in comparison to that of acetonitrile.

  18. Combined effect of water loss and wounding stress on gene activation of metabolic pathways associated with phenolic biosynthesis in carrot

    Science.gov (United States)

    Becerra-Moreno, Alejandro; Redondo-Gil, Mónica; Benavides, Jorge; Nair, Vimal; Cisneros-Zevallos, Luis; Jacobo-Velázquez, Daniel A.

    2015-01-01

    The application of postharvest abiotic stresses is an effective strategy to activate the primary and secondary metabolism of plants inducing the accumulation of antioxidant phenolic compounds. In the present study, the effect of water stress applied alone and in combination with wounding stress on the activation of primary (shikimic acid) and secondary (phenylpropanoid) metabolic pathways related with the accumulation of phenolic compound in plants was evaluated. Carrot (Daucus carota) was used as model system for this study, and the effect of abiotic stresses was evaluated at the gene expression level and on the accumulation of metabolites. As control of the study, whole carrots were stored under the same conditions. Results demonstrated that water stress activated the primary and secondary metabolism of carrots, favoring the lignification process. Likewise, wounding stress induced higher activation of the primary and secondary metabolism of carrots as compared to water stress alone, leading to higher accumulation of shikimic acid, phenolic compounds, and lignin. Additional water stress applied on wounded carrots exerted a synergistic effect on the wound-response at the gene expression level. For instance, when wounded carrots were treated with water stress, the tissue showed 20- and 14-fold increases in the relative expression of 3-deoxy-D-arabino-heptulosanate synthase and phenylalanine ammonia-lyase genes, respectively. However, since lignification was increased, lower accumulation of phenolic compounds was detected. Indicatively, at 48 h of storage, wounded carrots treated with water stress showed ~31% lower levels of phenolic compounds and ~23% higher lignin content as compared with wounded controls. In the present study, it was demonstrated that water stress is one of the pivotal mechanism of the wound-response in carrot. Results allowed the elucidation of strategies to induce the accumulation of specific primary or secondary metabolites when plants are

  19. Combined effect of water loss and wounding stress on gene activation of metabolic pathways associated with phenolic biosynthesis in carrot.

    Science.gov (United States)

    Becerra-Moreno, Alejandro; Redondo-Gil, Mónica; Benavides, Jorge; Nair, Vimal; Cisneros-Zevallos, Luis; Jacobo-Velázquez, Daniel A

    2015-01-01

    The application of postharvest abiotic stresses is an effective strategy to activate the primary and secondary metabolism of plants inducing the accumulation of antioxidant phenolic compounds. In the present study, the effect of water stress applied alone and in combination with wounding stress on the activation of primary (shikimic acid) and secondary (phenylpropanoid) metabolic pathways related with the accumulation of phenolic compound in plants was evaluated. Carrot (Daucus carota) was used as model system for this study, and the effect of abiotic stresses was evaluated at the gene expression level and on the accumulation of metabolites. As control of the study, whole carrots were stored under the same conditions. Results demonstrated that water stress activated the primary and secondary metabolism of carrots, favoring the lignification process. Likewise, wounding stress induced higher activation of the primary and secondary metabolism of carrots as compared to water stress alone, leading to higher accumulation of shikimic acid, phenolic compounds, and lignin. Additional water stress applied on wounded carrots exerted a synergistic effect on the wound-response at the gene expression level. For instance, when wounded carrots were treated with water stress, the tissue showed 20- and 14-fold increases in the relative expression of 3-deoxy-D-arabino-heptulosanate synthase and phenylalanine ammonia-lyase genes, respectively. However, since lignification was increased, lower accumulation of phenolic compounds was detected. Indicatively, at 48 h of storage, wounded carrots treated with water stress showed ~31% lower levels of phenolic compounds and ~23% higher lignin content as compared with wounded controls. In the present study, it was demonstrated that water stress is one of the pivotal mechanism of the wound-response in carrot. Results allowed the elucidation of strategies to induce the accumulation of specific primary or secondary metabolites when plants are

  20. Combined effect of water loss and wounding stress on gene activation of metabolic pathways associated with phenolic biosynthesis in carrot

    Directory of Open Access Journals (Sweden)

    Alejandro eBecerra-Moreno

    2015-10-01

    Full Text Available Abstract: The application of postharvest abiotic stresses is an effective strategy to activate the primary and secondary metabolism of plants inducing the accumulation of antioxidant phenolic compounds. In the present study, the effect of water stress applied alone and in combination with wounding stress on the activation of primary (shikimic acid and secondary (phenylpropanoid metabolic pathways related with the accumulation of phenolic compound in plants was evaluated. Carrot (Daucus carota was used as model system for this study, and the effect of abiotic stresses was evaluated at the gene expression level and on the accumulation of metabolites. As control of the study, whole carrots were stored under the same conditions. Results demonstrated that water stress activated the primary and secondary metabolism of carrots, favoring the lignification process. Likewise, wounding stress induced higher activation of the primary and secondary metabolism of carrots as compared to water stress alone, leading to higher accumulation of shikimic acid, phenolic compounds and lignin. Additional water stress applied on wounded carrots exerted a synergistic effect on the wound-response at the gene expression level. For instance, when wounded carrots were treated with water stress, the tissue showed 20- and 14-fold increases in the relative expression of 3-deoxy-D-arabino-heptulosanate synthase and phenylalanine ammonia-lyase genes, respectively. However, since lignification was increased, lower accumulation of phenolic compounds was detected. Indicatively, at 48 h of storage, wounded carrots treated with water stress showed ~31% lower levels of phenolic compounds and ~23% higher lignin content as compared with wounded controls. In the present study, it was demonstrated that water stress is one of the pivotal mechanism of the wound-response in carrot. Results allowed the elucidation of strategies to induce the accumulation of specific primary or secondary

  1. Stability and changes in astaxanthin ester composition from Haematococcus pluvialis during storage

    Science.gov (United States)

    Miao, Fengping; Geng, Yahong; Lu, Dayan; Zuo, Jincheng; Li, Yeguang

    2013-11-01

    In this paper, we investigated the effects of temperature, oxygen, antioxidants, and corn germ oil on the stability of astaxanthin from Haematococcus pluvialis under different storage conditions, and changes in the composition of astaxanthin esters during storage using high performance liquid chromatography and spectrophotometry. Oxygen and high temperatures (22-25°C) significantly reduced the stability of astaxanthin esters. Corn germ oil and antioxidants (ascorbic acid and vitamin E) failed to protect astaxanthin from oxidation, and actually significantly increased the instability of astaxanthin. A change in the relative composition of astaxanthin esters was observed after 96 weeks of long-term storage. During storage, the relative amounts of free astaxanthin and astaxanthin monoesters declined, while the relative amount of astaxanthin diesters increased. Thus, the ratio of astaxanthin diester to monoester increased, and this ratio could be used to indicate if astaxanthin esters have been properly preserved. If the ratio is greater than 0.2, it suggests that the decrease in astaxanthin content could be higher than 20%. Our results show that storing algal powder from H. pluvialis or other natural astaxanthin products under vacuum and in the dark below 4°C is the most economical and applicable storage method for the large-scale production of astaxanthin from H. pluvialis. This storage method can produce an astaxanthin preservation rate of at least 80% after 96 weeks of storage.

  2. Astaxanthin synthesis by Xanthophyllomyces dendrorhous DSM 5626 and its astaxanthin overproducing mutants on xylose media under diferent illumination

    Directory of Open Access Journals (Sweden)

    Barbara Stachowiak

    2014-09-01

    Full Text Available Background. Astaxanthin is the most important and expensive carotenoid pigment used in aquaculture. Its commercial attractiveness is also related with its antioxidant potential. XanthophyUomyces dendrorhous yeast is considered to be promising for commercial production of astaxanthin. The aim of this study was to investigate the possibility of the growth and astaxanthin production by X. dendrorhous strains 011 media containing xylose under different illumination. Material and methods. A', dendrorhous DSM 5626 and its mutants: 10BE and 26UV were used in this study. The cultures were carried out 011 hydrolysed rye stillage (HS and YM medium with xylose (YM-K. Cell concentration, total carotenoid and astaxanthin yields were assessed in 5-day cultures. The effect of illumination in the range of 0-5.000 lx 011 growth and on astaxanthin production of yeasts in cultures run 011 YM-K medium was also examined. Results. For the tested yeast strains better growth parameters and astaxanthin yields were obtained on the YM-K medium. 011 which for all strains the highest pigment yields were recorded at 600-1.000 lx. The highest concentration of astaxanthin in cells was recorded for 26UV in a culture at 1.000 lx (0.51 gkg-1 DCW. The volume yield of the pigment regardless of strain was highest in cultures at 600 lx. In this case 10BE was found to be the best astaxanthin producer with a yield of 2.15 mg dm-3. Conclusions. Astaxanthin synthesis in X. dendrorhous DSM 5626 and its mutants was better 011 YM-K medium comparing to hydrolysed rye stillage. Moreover, carotenogenesis in the studied yeast strains was subjected to marked photoregulation. Illumination within the range of 600-1.000 lx promotes carotenogenesis and astaxanthin production, while exceeding a certain light capacity results in microbial cell death.

  3. Regulation of FA and TAG biosynthesis pathway genes in endosperms and embryos of high and low oil content genotypes of Jatropha curcas L.

    Science.gov (United States)

    Sood, Archit; Chauhan, Rajinder Singh

    2015-09-01

    The rising demand for biofuels has raised concerns about selecting alternate and promising renewable energy crops which do not compete with food supply. Jatropha (Jatropha curcas L.), a non-edible energy crop of the family euphorbiaceae, has the potential of providing biodiesel feedstock due to the presence of high proportion of unsaturated fatty acids (75%) in seed oil which is mainly accumulated in endosperm and embryo. The molecular basis of seed oil biosynthesis machinery has been studied in J. curcas, however, what genetic differences contribute to differential oil biosynthesis and accumulation in genotypes varying for oil content is poorly understood. We investigated expression profile of 18 FA and TAG biosynthetic pathway genes in different developmental stages of embryo and endosperm from high (42%) and low (30%) oil content genotypes grown at two geographical locations. Most of the genes showed relatively higher expression in endosperms of high oil content genotype, whereas no significant difference was observed in endosperms versus embryos of low oil content genotype. The promoter regions of key genes from FA and TAG biosynthetic pathways as well as other genes implicated in oil accumulation were analyzed for regulatory elements and transcription factors specific to oil or lipid accumulation in plants such as Dof, CBF (LEC1), SORLIP, GATA and Skn-1_motif etc. Identification of key genes from oil biosynthesis and regulatory elements specific to oil deposition will be useful not only in dissecting the molecular basis of high oil content but also improving seed oil content through transgenic or molecular breeding approaches. PMID:26134579

  4. Accurate quantification of astaxanthin from Haematococcus crude extract spectrophotometrically

    Science.gov (United States)

    Li, Yeguang; Miao, Fengping; Geng, Yahong; Lu, Dayan; Zhang, Chengwu; Zeng, Mingtao

    2012-07-01

    The influence of alkali on astaxanthin and the optimal working wave length for measurement of astaxanthin from Haematococcus crude extract were investigated, and a spectrophotometric method for precise quantification of the astaxanthin based on the method of Boussiba et al. was established. According to Boussiba's method, alkali treatment destroys chlorophyll. However, we found that: 1) carotenoid content declined for about 25% in Haematococcus fresh cysts and up to 30% in dry powder of Haematococcus broken cysts after alkali treatment; and 2) dimethyl sulfoxide (DMSO)-extracted chlorophyll of green Haematococcus bares little absorption at 520-550 nm. Interestingly, a good linear relationship existed between absorbance at 530 nm and astaxanthin content, while an unknown interference at 540-550 nm was detected in our study. Therefore, with 530 nm as working wavelength, the alkali treatment to destroy chlorophyll was not necessary and the influence of chlorophyll, other carotenoids, and the unknown interference could be avoided. The astaxanthin contents of two samples were measured at 492 nm and 530 nm; the measured values at 530 nm were 2.617 g/100 g and 1.811 g/100 g. When compared with the measured values at 492 nm, the measured values at 530 nm decreased by 6.93% and 11.96%, respectively. The measured values at 530 nm are closer to the true astaxanthin contents in the samples. The data show that 530 nm is the most suitable wave length for spectrophotometric determination to the astaxanthin in Haematococcus crude extract.

  5. Astaxanthin: A Potential Therapeutic Agent in Cardiovascular Disease

    Directory of Open Access Journals (Sweden)

    Robert G. Fassett

    2011-03-01

    Full Text Available Astaxanthin is a xanthophyll carotenoid present in microalgae, fungi, complex plants, seafood, flamingos and quail. It is an antioxidant with anti-inflammatory properties and as such has potential as a therapeutic agent in atherosclerotic cardiovascular disease. Synthetic forms of astaxanthin have been manufactured. The safety, bioavailability and effects of astaxanthin on oxidative stress and inflammation that have relevance to the pathophysiology of atherosclerotic cardiovascular disease, have been assessed in a small number of clinical studies. No adverse events have been reported and there is evidence of a reduction in biomarkers of oxidative stress and inflammation with astaxanthin administration. Experimental studies in several species using an ischaemia-reperfusion myocardial model demonstrated that astaxanthin protects the myocardium when administered both orally or intravenously prior to the induction of the ischaemic event. At this stage we do not know whether astaxanthin is of benefit when administered after a cardiovascular event and no clinical cardiovascular studies in humans have been completed and/or reported. Cardiovascular clinical trials are warranted based on the physicochemical and antioxidant properties, the safety profile and preliminary experimental cardiovascular studies of astaxanthin.

  6. 雨生红球藻合成虾青素过程中的分泌铵离子%Concomitant NH+4 Secretion During Astaxanthin Synthesis in Haematococcus pluvialis Under High Irradiance and Nitrogen Deficient Conditions

    Institute of Scientific and Technical Information of China (English)

    董庆霖; 赵学明; 刑向英; 胡建中; 巩继贤

    2007-01-01

    The present study is focused on protein degradation during astaxanthin synthesis in Haematococcus pluvialis under high irradiance and nitrogen deficient conditions. It was found that with the onset of astaxanthin synthesis in the cultures of high light and nitrogen-free (HF), high light and nitrogen-repletion (HR), and low light and nitrogen-free (LF), (1) endopeptidase (EP) activities increased along with decrease in protein content, (2) aspar-agine in HF and HR rose significantly before the first 4 and 5 day, but fell after that time. While, it increased slowly and continuously in LF, (3) ammonium increased continuously in HF and HR, whereas in LF, it was detected on the sixth day, and increased slowly on the following days. By contrast, in low light and nitrogen-repletion culture, (LR), the contents of protein and asparagine as well as EP activity were maintained relatively constant, no astaxanthin and ammonium were detected. Furthermore, when HF was sealed and bubbled with CO2-free gas (O2 and N2), astaxanthin content increased as the protein level decreased. These results strongly suggest that (1) the degraded protein served as a substitutive carbon source, to some extent, for the biosynthesis of astaxanthin, (2) endopeptidase was involved in the degradative process, (3) for detoxification, part of the ammonium generated by protein degradation was transiently stored in asparagine, whereas the rest of it was expelled into the culture broth.

  7. The Early Stages of Taxol Biosynthesis: An Interim Report on the Synthesis and Identification of Early Pathway Metabolites

    OpenAIRE

    Guerra-Bubb, Jennifer; Croteau, Rodney; Williams, Robert M.

    2012-01-01

    The biosynthesis of the anti-cancer drug taxol (paclitaxel) has required the collaborative efforts of several research groups to tackle the synthesis and labeling of putative biosynthetic intermediates, in concert with the identification, cloning and functional expression of the biosynthetic genes responsible for the construction of this complex natural product. Based on a combination of precursor labeling and incorporation experiments, and metabolite isolation from Taxus spp., a picture of t...

  8. AtROS1 overexpression provides evidence for epigenetic regulation of genes encoding enzymes of flavonoid biosynthesis and antioxidant pathways during salt stress in transgenic tobacco.

    Science.gov (United States)

    Bharti, Poonam; Mahajan, Monika; Vishwakarma, Ajay K; Bhardwaj, Jyoti; Yadav, Sudesh Kumar

    2015-09-01

    In plants, epigenetic changes have been identified as regulators of developmental events during normal growth as well as environmental stress exposures. Flavonoid biosynthetic and antioxidant pathways play a significant role in plant defence during their exposure to environmental cues. The aim of this study was to unravel whether genes encoding enzymes of flavonoid biosynthetic and antioxidant pathways are under epigenetic regulation, particularly DNA methylation, during salt stress. For this, a repressor of silencing from Arabidopsis, AtROS1, was overexpressed in transgenic tobacco. Generated transgenics were evaluated to examine the influence of AtROS1 on methylation status of promoters as well as on coding regions of genes encoding enzymes of flavonoids biosynthesis and antioxidant pathways. Overexpression of AtROS1 increases the demethylation levels of both promoters as well as coding regions of genes encoding chalcone synthase, chalcone isomerase, flavanone 3-hydroxylase, flavonol synthase, dihydroflavonol 4-reductase, and anthocyanidin synthase of the flavonoid biosynthetic pathway, and glutathione S-transferase, ascorbate peroxidase, glutathione peroxidase, and glutathione reductase of the antioxidant pathway during control conditions. The level of demethylation was further increased at promoters as well as coding regions of these genes during salt-stress conditions. Transgenic tobacco overexpressing AtROS1 showed tolerance to salt stress that could have been due to the higher expression levels of the genes encoding enzymes of the flavonoid biosynthetic and antioxidant pathways. This is the first comprehensive study documenting the epigenetic regulation of flavonoid biosynthetic and antioxidant pathways during salt-stress exposure of plants. PMID:26116024

  9. The Vitamin B6 Biosynthesis Pathway in Streptococcus pneumoniae Is Controlled by Pyridoxal 5′-Phosphate and the Transcription Factor PdxR and Has an Impact on Ear Infection

    OpenAIRE

    El Qaidi, Samir; Yang, Jun; Zhang, Jing-Ren; Metzger, Dennis W.; Bai, Guangchun

    2013-01-01

    Vitamin B6 is an essential cofactor for a large number of enzymes in both prokaryotes and eukaryotes. In this study, we characterized the pyridoxal 5′-phosphate (PLP) biosynthesis pathway in Streptococcus pneumoniae. Our results revealed that S. pneumoniae possesses a de novo vitamin B6 biosynthesis pathway encoded by the pdxST genes. Purified PdxS functionally displayed as PLP synthase, whereas PdxT exhibited glutaminase activity in vitro. Deletion of pdxS, but not pdxT, resulted in a vitami...

  10. Analysis of the Isoprenoid Biosynthesis Pathways in Listeria monocytogenes Reveals a Role for the Alternative 2-C-Methyl-d-Erythritol 4-Phosphate Pathway in Murine Infection▿

    OpenAIRE

    Begley, Máire; Bron, Peter A; Heuston, Sinead; Casey, Pat G.; Englert, Nadine; Wiesner, Jochen; Jomaa, Hassan; Gahan, Cormac G. M.; Hill, Colin

    2008-01-01

    Most bacteria synthesize isoprenoids through one of two essential pathways which provide the basic building block, isopentyl diphosphate (IPP): either the classical mevalonate pathway or the alternative non-mevalonate 2-C-methyl-d-erythritol 4-phosphate (MEP) pathway. However, postgenomic analyses of the Listeria monocytogenes genome revealed that this pathogen possesses the genetic capacity to produce the complete set of enzymes involved in both pathways. The nonpathogenic species Listeria i...

  11. Mutations in Escherichia coli aceE and ribB genes allow survival of strains defective in the first step of the isoprenoid biosynthesis pathway.

    Directory of Open Access Journals (Sweden)

    Jordi Perez-Gil

    Full Text Available A functional 2-C-methyl-D-erythritol 4-phosphate (MEP pathway is required for isoprenoid biosynthesis and hence survival in Escherichia coli and most other bacteria. In the first two steps of the pathway, MEP is produced from the central metabolic intermediates pyruvate and glyceraldehyde 3-phosphate via 1-deoxy-D-xylulose 5-phosphate (DXP by the activity of the enzymes DXP synthase (DXS and DXP reductoisomerase (DXR. Because the MEP pathway is absent from humans, it was proposed as a promising new target to develop new antibiotics. However, the lethal phenotype caused by the deletion of DXS or DXR was found to be suppressed with a relatively high efficiency by unidentified mutations. Here we report that several mutations in the unrelated genes aceE and ribB rescue growth of DXS-defective mutants because the encoded enzymes allowed the production of sufficient DXP in vivo. Together, this work unveils the diversity of mechanisms that can evolve in bacteria to circumvent a blockage of the first step of the MEP pathway.

  12. Structure investigations on assembled astaxanthin molecules

    Science.gov (United States)

    Köpsel, Christian; Möltgen, Holger; Schuch, Horst; Auweter, Helmut; Kleinermanns, Karl; Martin, Hans-Dieter; Bettermann, Hans

    2005-08-01

    The carotenoid r, r-astaxanthin (3 R,3' R-dihydroxy-4,4'-diketo-β-carotene) forms different types of aggregates in acetone-water mixtures. H-type aggregates were found in mixtures with a high part of water (e.g. 1:9 acetone-water mixture) whereas two different types of J-aggregates were identified in mixtures with a lower part of water (3:7 acetone-water mixture). These aggregates were characterized by recording UV/vis-absorption spectra, CD-spectra and fluorescence emissions. The sizes of the molecular assemblies were determined by dynamic light scattering experiments. The hydrodynamic diameter of the assemblies amounts 40 nm in 1:9 acetone-water mixtures and exceeds up to 1 μm in 3:7 acetone-water mixtures. Scanning tunneling microscopy monitored astaxanthin aggregates on graphite surfaces. The structure of the H-aggregate was obtained by molecular modeling calculations. The structure was confirmed by calculating the electronic absorption spectrum and the CD-spectrum where the molecular modeling structure was used as input.

  13. Astaxanthin as a Potential Neuroprotective Agent for Neurological Diseases

    Directory of Open Access Journals (Sweden)

    Haijian Wu

    2015-09-01

    Full Text Available Neurological diseases, which consist of acute injuries and chronic neurodegeneration, are the leading causes of human death and disability. However, the pathophysiology of these diseases have not been fully elucidated, and effective treatments are still lacking. Astaxanthin, a member of the xanthophyll group, is a red-orange carotenoid with unique cell membrane actions and diverse biological activities. More importantly, there is evidence demonstrating that astaxanthin confers neuroprotective effects in experimental models of acute injuries, chronic neurodegenerative disorders, and neurological diseases. The beneficial effects of astaxanthin are linked to its oxidative, anti-inflammatory, and anti-apoptotic characteristics. In this review, we will focus on the neuroprotective properties of astaxanthin and explore the underlying mechanisms in the setting of neurological diseases.

  14. Multispectral Imaging for Determination of Astaxanthin Concentration in Salmonids

    DEFF Research Database (Denmark)

    Dissing, Bjørn Skovlund; Nielsen, Michael Engelbrecht; Ersbøll, Bjarne Kjær; Frosch, Stina

    2011-01-01

    Multispectral imaging has been evaluated for characterization of the concentration of a specific cartenoid pigment; astaxanthin. 59 fillets of rainbow trout, Oncorhynchus mykiss, were filleted and imaged using a rapid multispectral imaging device for quantitative analysis. The multispectral imaging...... device captures reflection properties in 19 distinct wavelength bands, prior to determination of the true concentration of astaxanthin. The samples ranged from 0.20 to 4.34 mu g per g fish. A PLSR model was calibrated to predict astaxanthin concentration from novel images, and showed good results with a...... RMSEP of 0.27. For comparison a similar model were built for normal color images, which yielded a RMSEP of 0.45. The acquisition speed of the multispectral imaging system and the accuracy of the PLSR model obtained suggest this method as a promising technique for rapid in-line estimation of astaxanthin...

  15. Amino Acids Attenuate Insulin Action on Gluconeogenesis and Promote Fatty Acid Biosynthesis via mTORC1 Signaling Pathway in trout Hepatocytes

    Directory of Open Access Journals (Sweden)

    Weiwei Dai

    2015-06-01

    Full Text Available Background/Aims: Carnivores exhibit poor utilization of dietary carbohydrates and glucose intolerant phenotypes, yet it remains unclear what are the causal factors and underlying mechanisms. We aimed to evaluate excessive amino acids (AAs-induced effects on insulin signaling, fatty acid biosynthesis and glucose metabolism in rainbow trout and determine the potential involvement of mTORC1 and p38 MAPK pathway. Methods: We stimulated trout primary hepatocytes with different AA levels and employed acute administration of rapamycin to inhibit mTORC1 activation. Results: Increased AA levels enhanced the phosphorylation of ribosomal protein S6 kinase (S6K1, S6, and insulin receptor substrate 1 (IRS-1 on Ser302 but suppressed Akt and p38 phosphorylation; up-regulated the expression of genes related to gluconeogenesis and fatty acid biosynthesis. mTORC1 inhibition not only inhibited the phosphorylation of mTORC1 downstream targets, but also blunted IRS-1 Ser302 phosphorylation and restored excessive AAs-suppressed Akt phosphorylation. Rapamycin also inhibited fatty acid biosynthetic and gluconeogenic gene expression. Conclusion: High levels of AAs up-regulate hepatic fatty acid biosynthetic gene expression through an mTORC1-dependent manner, while attenuate insulin-mediated repression of gluconeogenesis through elevating IRS-1 Ser302 phosphorylation, which in turn impairs Akt activation and thereby weakening insulin action. We propose that p38 MAPK probably also involves in these AAs-induced metabolic changes.

  16. Astaxanthin as a Potential Neuroprotective Agent for Neurological Diseases

    OpenAIRE

    Haijian Wu; Huanjiang Niu; Anwen Shao; Cheng Wu; Brandon J Dixon; Jianmin Zhang; Shuxu Yang; Yirong Wang

    2015-01-01

    Neurological diseases, which consist of acute injuries and chronic neurodegeneration, are the leading causes of human death and disability. However, the pathophysiology of these diseases have not been fully elucidated, and effective treatments are still lacking. Astaxanthin, a member of the xanthophyll group, is a red-orange carotenoid with unique cell membrane actions and diverse biological activities. More importantly, there is evidence demonstrating that astaxanthin confers neuroprotective...

  17. Multispectral Imaging for Determination of Astaxanthin Concentration in Salmonids

    OpenAIRE

    Dissing, Bjørn Skovlund; Nielsen, Michael Engelbrecht; Ersbøll, Bjarne Kjær; Frosch, Stina

    2011-01-01

    Multispectral imaging has been evaluated for characterization of the concentration of a specific cartenoid pigment; astaxanthin. 59 fillets of rainbow trout, Oncorhynchus mykiss, were filleted and imaged using a rapid multispectral imaging device for quantitative analysis. The multispectral imaging device captures reflection properties in 19 distinct wavelength bands, prior to determination of the true concentration of astaxanthin. The samples ranged from 0.20 to 4.34 mu g per g fish. A PLSR ...

  18. Evaluation of hepatoprotective and antioxidant activity of astaxanthin and astaxanthin esters from microalga-Haematococcus pluvialis.

    Science.gov (United States)

    Rao, A Ranga; Sarada, R; Shylaja, M D; Ravishankar, G A

    2015-10-01

    Effect of isolated astaxanthin (ASX) and astaxanthin esters (ASXEs) from green microalga-Haematococcus pluvialis on hepatotoxicity and antioxidant activity against carbon tetrachloride (CCl4) induced toxicity in rats was compared with synthetic astaxanthin (SASX). ASX, ASXEs, and SASX, all dissolved in olive oil, fed to rats with 100 and 250 μg/kg b.w for 14 days. They were evaluated for their hepatoprotective and antioxidant activity by measuring appropriate enzymes. Among the treated groups, the SGPT, SGOT and ALP levels were decreased by 2, 2.4, and 1.5 fold in ASXEs treated group at 250 μg/Kg b.w. when compared to toxin group. Further, antioxidant enzymes catalase, glutathione, superoxide dismutase and lipid peroxidase levels were estimated in treated groups, their levels were reduced by 30-50 % in the toxin group, however these levels restored by 136.95 and 238.48 % in ASXEs treated group at 250 μg/kg. The lipid peroxidation was restored by 5.2 and 2.8 fold in ASXEs and ASX treated groups at 250 μg/kg. The total protein, albumin and bilirubin contents were decreased in toxin group, whereas normalized in ASXEs treated group. These results indicates that ASX and ASXEs have better hepatoprotection and antioxidant activity, therefore can be used in pharmaceutical and nutraceutical applications and also extended to use as food colorant. PMID:26396419

  19. Multiple Mechanisms of Anti-Cancer Effects Exerted by Astaxanthin

    Directory of Open Access Journals (Sweden)

    Li Zhang

    2015-07-01

    Full Text Available Astaxanthin (ATX is a xanthophyll carotenoid which has been approved by the United States Food and Drug Administration (USFDA as food colorant in animal and fish feed. It is widely found in algae and aquatic animals and has powerful anti-oxidative activity. Previous studies have revealed that ATX, with its anti-oxidative property, is beneficial as a therapeutic agent for various diseases without any side effects or toxicity. In addition, ATX also shows preclinical anti-tumor efficacy both in vivo and in vitro in various cancer models. Several researches have deciphered that ATX exerts its anti-proliferative, anti-apoptosis and anti-invasion influence via different molecules and pathways including signal transducer and activator of transcription 3 (STAT3, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB and peroxisome proliferator-activated receptor gamma (PPARγ. Hence, ATX shows great promise as chemotherapeutic agents in cancer. Here, we review the rapidly advancing field of ATX in cancer therapy as well as some molecular targets of ATX.

  20. A decade of molecular understanding of withanolide biosynthesis and in vitro studies in Withania somnifera (L. Dunal: Prospects and perspectives for pathway engineering

    Directory of Open Access Journals (Sweden)

    Niha eDhar

    2015-11-01

    Full Text Available Withania somnifera, a multipurpose medicinal plant is a rich reservoir of pharmaceutically active triterpenoids that are steroidal lactones known as withanolides. Though the plant has been well characterized in terms of phytochemical profiles as well as pharmaceutical activities, limited attempts have been made to decipher the biosynthetic route and identification of key regulatory genes involved in withanolide biosynthesis. This scenario limits biotechnological interventions for enhanced production of bioactive compounds. Nevertheless, recent emergent trends vis-à-vis, the exploration of genomic, transcriptomic, proteomic, metabolomic and in vitro studies have opened new vistas regarding pathway engineering of withanolide production. During recent years, various strategic pathway genes have been characterized with significant amount of regulatory studies which allude towards development of molecular circuitries for production of key intermediates or end products in heterologous hosts. Another pivotal aspect covering redirection of metabolic flux for channelizing the precursor pool towards enhanced withanolide production has also been attained by deciphering decisive branch point(s as robust targets for pathway modulation. With these perspectives, the current review provides a detailed overview of various studies undertaken by the authors and collated literature related to molecular and in vitro approaches employed in W. Somnifera for understanding various molecular network interactions in entirety.

  1. Magnolol Affects Cellular Proliferation, Polyamine Biosynthesis and Catabolism-Linked Protein Expression and Associated Cellular Signaling Pathways in Human Prostate Cancer Cells in vitro

    Directory of Open Access Journals (Sweden)

    Brendan T. McKeown

    2015-01-01

    Full Text Available Background: Prostate cancer is the most commonly diagnosed form of cancer in men in Canada and the United States. Both genetic and environmental factors contribute to the development and progression of many cancers, including prostate cancer. Context and purpose of this study: This study investigated the effects of magnolol, a compound found in the roots and bark of the magnolia tree Magnolia officinalis, on cellular proliferation and proliferation-linked activities of PC3 human prostate cancer cells in vitro. Results: PC3 cells exposed to magnolol at a concentration of 80 μM for 6 hours exhibited decreased protein expression of ornithine decarboxylase, a key regulator in polyamine biosynthesis, as well as affecting the expression of other proteins involved in polyamine biosynthesis and catabolism. Furthermore, protein expression of the R2 subunit of ribonucleotide reductase, a key regulatory protein associated with DNA synthesis, was significantly decreased. Finally, the MAPK (mitogen-activated protein kinase, PI3K (phosphatidylinositol 3-kinase, NFκB (nuclear factor of kappa-light-chain-enhancer of activated B cells and AP-1 (activator protein 1 cellular signaling pathways were assayed to determine which, if any, of these pathways magnolol exposure would alter. Protein expressions of p-JNK-1 and c-jun were significantly increased while p-p38, JNK-1/2, PI3Kp85, p-PI3Kp85, p-Akt, NFκBp65, p-IκBα and IκBα protein expressions were significantly decreased. Conclusions: These alterations further support the anti-proliferative effects of magnolol on PC3 human prostate cancer cells in vitro and suggest that magnolol may have potential as a novel anti-prostate cancer agent.

  2. Effect of dietary bile extracts on serum response of astaxanthin in rainbow trout (Oncorhynchus mykiss)

    OpenAIRE

    Mendes-Pinto, M.M.; Choubert, G. (collab.)

    2004-01-01

    Effects of porcine bile extracts added at three different dietary concentrations 0, 10 and 20 g kg)1 were studied on astaxanthin serum concentration in rainbow trout (mean weight 200 ± 7 g). Astaxanthin from micro-algae Haematococcus pluvialis and synthetic astaxanthin (CAROPHYLL pink) were incorporated in diets of rainbow trout at a rate of 100 mg astaxanthin kg)1 of feed. Fish were hand fed twice a day. After 5 days of feeding there was a significant effect of the ...

  3. Sulforaphane, a cancer chemopreventive agent, induces pathways associated with membrane biosynthesis in response to tissue damage by aflatoxin B1

    International Nuclear Information System (INIS)

    Aflatoxin B1 (AFB1) is one of the major risk factors for liver cancer globally. A recent study showed that sulforaphane (SF), a potent inducer of phase II enzymes that occurs naturally in widely consumed vegetables, effectively induces hepatic glutathione S-transferases (GSTs) and reduces levels of hepatic AFB1-DNA adducts in AFB1-exposed Sprague Dawley rats. The present study characterized the effects of SF pre-treatment on global gene expression in the livers of similarly treated male rats. Combined treatment with AFB1 and SF caused reprogramming of a network of genes involved in signal transduction and transcription. Changes in gene regulation were observable 4 h after AFB1 administration in SF-pretreated animals and may reflect regeneration of cells in the wake of AFB1-induced hepatotoxicity. At 24 h after AFB1 administration, significant induction of genes that play roles in cellular lipid metabolism and acetyl-CoA biosynthesis was detected in SF-pretreated AFB1-dosed rats. Induction of this group of genes may indicate a metabolic shift toward glycolysis and fatty acid synthesis to generate and maintain pools of intermediate molecules required for tissue repair, cell growth and compensatory hepatic cell proliferation. Collectively, gene expression data from this study provide insights into molecular mechanisms underlying the protective effects of SF against AFB1 hepatotoxicity and hepatocarcinogenicity, in addition to the chemopreventive activity of this compound as a GST inducer. - Highlights: • This study revealed sulforaphane (SF)-deregulated gene sets in aflatoxin B1 (AFB1)-treated rat livers. • SF redirects biochemical networks toward lipid biosynthesis in AFB1-dosed rats. • SF enhanced gene sets that would be expected to favor cell repair and regeneration

  4. Selection of Astaxanthin-Overproducing Mutants of Phaffia rhodozyma with β-Ionone

    OpenAIRE

    Lewis, M. J.; Ragot, N.; Berlant, M. C.; Miranda, M

    1990-01-01

    β-Ionone, an end ring analog of β-carotene, inhibits astaxanthin production in the red yeast Phaffia rhodozyma. Astaxanthin-overproducing mutants of this yeast are easily spotted on β-ionone-containing yeast malt agar plates. β-Ionone appears to block astaxanthin synthesis at the β-carotene level.

  5. Ribose-5-Phosphate Biosynthesis in Methanocaldococcus jannaschii Occurs in the Absence of a Pentose-Phosphate Pathway

    OpenAIRE

    Grochowski, Laura L.; Xu, Huimin; White, Robert H.

    2005-01-01

    Recent work has raised a question as to the involvement of erythrose-4-phosphate, a product of the pentose phosphate pathway, in the metabolism of the methanogenic archaea (R. H. White, Biochemistry 43:7618-7627, 2004). To address the possible absence of erythrose-4-phosphate in Methanocaldococcus jannaschii, we have assayed cell extracts of this methanogen for the presence of this and other intermediates in the pentose phosphate pathway and have determined and compared the labeling patterns ...

  6. Pathways and Subcellular Compartmentation of NAD Biosynthesis in Human Cells: FROM ENTRY OF EXTRACELLULAR PRECURSORS TO MITOCHONDRIAL NAD GENERATION*

    OpenAIRE

    Nikiforov, Andrey; Dölle, Christian; Niere, Marc; Ziegler, Mathias

    2011-01-01

    NAD is a vital redox carrier, and its degradation is a key element of important regulatory pathways. NAD-mediated functions are compartmentalized and have to be fueled by specific biosynthetic routes. However, little is known about the different pathways, their subcellular distribution, and regulation in human cells. In particular, the route(s) to generate mitochondrial NAD, the largest subcellular pool, is still unknown. To visualize organellar NAD changes in cells, we targeted poly(ADP-ribo...

  7. Effect of carotenoid source and dietary lipid content on blood astaxanthin concentration in rainbow trout (Oncorhynchus mykiss)

    OpenAIRE

    Barbosa, M. J.; Morais, R; Choubert, G. (collab.)

    1999-01-01

    Astaxanthin concentration in the blood of rainbow trout was studied in a feeding trial with two different astaxanthin sources: green algae Haematococcus pluvialis and commercial beadlets of 8% astaxanthin content (CAROPHYLL® Pink), and two different dietary lipid levels. The green algae contained 1.4% of carotenoids on a dry matter basis: free astaxanthin (

  8. Genomic and Biochemical Analysis of Lipid Biosynthesis in the Unicellular Rhodophyte Cyanidioschyzon merolae: Lack of a Plastidic Desaturation Pathway Results in the Coupled Pathway of Galactolipid Synthesis▿ †

    OpenAIRE

    Sato, Naoki; Moriyama, Takashi

    2007-01-01

    The acyl lipids making up the plastid membranes in plants and algae are highly enriched in polyunsaturated fatty acids and are synthesized by two distinct pathways, known as the prokaryotic and eukaryotic pathways, which are located within the plastids and the endoplasmic reticulum, respectively. Here we report the results of biochemical as well as genomic analyses of lipids and fatty acids in the unicellular rhodophyte Cyanidioschyzon merolae. All of the glycerolipids usually found in photos...

  9. Genes of the de novo and salvage biosynthesis pathways of vitamin B6 are regulated under oxidative stress in the plant pathogen Rhizoctonia solani

    Directory of Open Access Journals (Sweden)

    Jamil eSamsatly

    2016-01-01

    Full Text Available B6 is recognized as an important cofactor required for numerous metabolic enzymes, and has been shown to act as an antioxidant and play a role in stress responses. It can be synthesized through two different routes: salvage and de novo pathways. However, little is known about the possible function of the vitamin B6 pathways in the fungal plant pathogen Rhizoctonia solani. Using genome walking, the de novo biosynthetic pathway genes; RsolPDX1 and RsolPDX2 and the salvage biosynthetic pathway gene, RsolPLR were sequenced. The predicted amino acid sequences of the three genes had high degree of similarity to other fungal PDX1, PDX2, and PLR proteins and are closely related to other R. solani anastomosis groups. We also examined their regulation when subjected to ROS stress inducers, the superoxide generator paraquat, or H2O2, and compared it to the well-known antioxidant genes, catalase and glutathione-S-transferase (GST. The genes were differentially regulated with substantial transcript levels as high as 33 fold depending on the gene and type of stress reflecting that differences in the type of damage induced by ROS. Exogenous addition of the vitamers PN or PLP in culture medium significantly induced the transcription of the vitamin B6 de novo encoding genes as early as 0.5 hour post treatment (HPT. On the other hand, transcription of RsolPLR was vitamer-specific; a down regulation upon supplementation of PN and upregualtion with PLP. Our results suggest that accumulation of ROS in R. solani mycelia was linked to transcriptional regulation of the three genes and R. solani vitamin B6 biosynthesis machinery could be implicated similar to catalases and GST as an antioxidant stress protector against oxidative stress.

  10. Broad substrate specificity of phosphotransbutyrylase from Listeria monocytogenes: A potential participant in an alternative pathway for provision of acyl CoA precursors for fatty acid biosynthesis.

    Science.gov (United States)

    Sirobhushanam, Sirisha; Galva, Charitha; Sen, Suranjana; Wilkinson, Brian J; Gatto, Craig

    2016-09-01

    Listeria monocytogenes, the causative organism of the serious food-borne disease listeriosis, has a membrane abundant in branched-chain fatty acids (BCFAs). BCFAs are normally biosynthesized from branched-chain amino acids via the activity of branched chain α-keto acid dehydrogenase (Bkd), and disruption of this pathway results in reduced BCFA content in the membrane. Short branched-chain carboxylic acids (BCCAs) added as media supplements result in incorporation of BCFAs arising from the supplemented BCCAs in the membrane of L. monocytogenes bkd mutant MOR401. High concentrations of the supplements also effect similar changes in the membrane of the wild type organism with intact bkd. Such carboxylic acids clearly act as fatty acid precursors, and there must be an alternative pathway resulting in the formation of their CoA thioester derivatives. Candidates for this are the enzymes phosphotransbutyrylase (Ptb) and butyrate kinase (Buk), the products of the first two genes of the bkd operon. Ptb from L. monocytogenes exhibited broad substrate specificity, a strong preference for branched-chain substrates, a lack of activity with acetyl CoA and hexanoyl CoA, and strict chain length preference (C3-C5). Ptb catalysis involved ternary complex formation. Additionally, Ptb could utilize unnatural branched-chain substrates such as 2-ethylbutyryl CoA, albeit with lower efficiency, consistent with a potential involvement of this enzyme in the conversion of the carboxylic acid additives into CoA primers for BCFA biosynthesis. PMID:27320015

  11. Modulating the metabolic flux through the biosynthesis pathways of branched-chain amino acids in corynebacterium glutamicum

    Czech Academy of Sciences Publication Activity Database

    Pátek, Miroslav; Elišáková, Veronika; Holátko, Jiří

    2004, s. 53. [Metabolic Engineering /5./. Squaw Creek (US), 19.09.2004-23.09.2004] R&D Projects: GA ČR GA525/04/0548 Institutional research plan: CEZ:AV0Z5020903 Keywords : corynebacterium glutamicum * pathway Subject RIV: EE - Microbiology, Virology

  12. Preparation of Astaxanthin Nanodispersions Using Gelatin-Based Stabilizer Systems

    Directory of Open Access Journals (Sweden)

    Navideh Anarjan

    2014-09-01

    Full Text Available The incorporation of lipophilic nutrients, such as astaxanthin (a fat soluble carotenoid in nanodispersion systems can either increase the water solubility, stability and bioavailability or widen their applications in aqueous food and pharmaceutical formulations. In this research, gelatin and its combinations with sucrose oleate as a small molecular emulsifier, sodium caseinate (SC as a protein and gum Arabic as a polysaccharide were used as stabilizer systems in the formation of astaxanthin nanodispersions via an emulsification-evaporation process. The results indicated that the addition of SC to gelatin in the stabilizer system could increase the chemical stability of astaxanthin nanodispersions significantly, while using a mixture of gelatin and sucrose oleate as a stabilizer led to production of nanodispersions with the smallest particle size (121.4 ± 8.6 nm. It was also shown that a combination of gelatin and gum Arabic could produce optimal astaxanthin nanodispersions in terms of physical stability (minimum polydispersity index (PDI and maximum zeta-potential. This study demonstrated that the mixture of surface active compounds showed higher emulsifying and stabilizing functionality compared to using them individually in the preparation of astaxanthin nanodispersions.

  13. Improving the Stability of Astaxanthin by Microencapsulation in Calcium Alginate Beads.

    Science.gov (United States)

    Lin, Shen-Fu; Chen, Ying-Chen; Chen, Ray-Neng; Chen, Ling-Chun; Ho, Hsiu-O; Tsung, Yu-Han; Sheu, Ming-Thau; Liu, Der-Zen

    2016-01-01

    There has been considerable interest in the biological functions of astaxanthin and its potential applications in the nutraceutical, cosmetics, food, and feed industries in recent years. However, the unstable structure of astaxanthin considerably limits its application. Therefore, this study reports the encapsulation of astaxanthin in calcium alginate beads using the extrusion method to improve its stability. This study also evaluates the stability of the encapsulated astaxanthin under different storage conditions. The evaluation of astaxanthin stability under various environmental factors reveals that temperature is the most influential environmental factor in astaxanthin degradation. Stability analysis shows that, regardless of the formulation used, the content of astaxanthin encapsulated in alginate beads remains above 90% of the original amount after 21 days of storage at 25°C. These results suggest that the proposed technique is a promising way to enhance the stability of other sensitive compounds. PMID:27093175

  14. Combined effect of water loss and wounding stress on gene activation of metabolic pathways associated with phenolic biosynthesis in carrot

    OpenAIRE

    Becerra-Moreno, Alejandro; Redondo-Gil, Mónica; Benavides, Jorge; Nair, Vimal; Cisneros-Zevallos, Luis; Daniel A. Jacobo-Velázquez

    2015-01-01

    The application of postharvest abiotic stresses is an effective strategy to activate the primary and secondary metabolism of plants inducing the accumulation of antioxidant phenolic compounds. In the present study, the effect of water stress applied alone and in combination with wounding stress on the activation of primary (shikimic acid) and secondary (phenylpropanoid) metabolic pathways related with the accumulation of phenolic compound in plants was evaluated. Carrot (Daucus carota) was us...

  15. Interspecies and Intraspecies Analysis of Trehalose Contents and the Biosynthesis Pathway Gene Family Reveals Crucial Roles of Trehalose in Osmotic-Stress Tolerance in Cassava

    Directory of Open Access Journals (Sweden)

    Bingying Han

    2016-07-01

    Full Text Available Trehalose is a nonreducing α,α-1,1-disaccharide in a wide range of organisms, and has diverse biological functions that range from serving as an energy source to acting as a protective/signal sugar. However, significant amounts of trehalose have rarely been detected in higher plants, and the function of trehalose in the drought-tolerant crop cassava (Manihot esculenta Crantz is unclear. We measured soluble sugar concentrations of nine plant species with differing levels of drought tolerance and 41 cassava varieties using high-performance liquid chromatography with evaporative light-scattering detector (HPLC-ELSD. Significantly high amounts of trehalose were identified in drought-tolerant crops cassava, Jatropha curcas, and castor bean (Ricinus communis. All cassava varieties tested contained high amounts of trehalose, although their concentrations varied from 0.23 to 1.29 mg·g−1 fresh weight (FW, and the trehalose level was highly correlated with dehydration stress tolerance of detached leaves of the varieties. Moreover, the trehalose concentrations in cassava leaves increased 2.3–5.5 folds in response to osmotic stress simulated by 20% PEG 6000. Through database mining, 24 trehalose pathway genes, including 12 trehalose-6-phosphate synthases (TPS, 10 trehalose-6-phosphate phosphatases (TPP, and two trehalases were identified in cassava. Phylogenetic analysis indicated that there were four cassava TPS genes (MeTPS1–4 that were orthologous to the solely active TPS gene (AtTPS1 and OsTPS1 in Arabidopsis and rice, and a new TPP subfamily was identified in cassava, suggesting that the trehalose biosynthesis activities in cassava had potentially been enhanced in evolutionary history. RNA-seq analysis indicated that MeTPS1 was expressed at constitutionally high level before and after osmotic stress, while other trehalose pathway genes were either up-regulated or down-regulated, which may explain why cassava accumulated high level of trehalose

  16. Interspecies and Intraspecies Analysis of Trehalose Contents and the Biosynthesis Pathway Gene Family Reveals Crucial Roles of Trehalose in Osmotic-Stress Tolerance in Cassava.

    Science.gov (United States)

    Han, Bingying; Fu, Lili; Zhang, Dan; He, Xiuquan; Chen, Qiang; Peng, Ming; Zhang, Jiaming

    2016-01-01

    Trehalose is a nonreducing α,α-1,1-disaccharide in a wide range of organisms, and has diverse biological functions that range from serving as an energy source to acting as a protective/signal sugar. However, significant amounts of trehalose have rarely been detected in higher plants, and the function of trehalose in the drought-tolerant crop cassava (Manihot esculenta Crantz) is unclear. We measured soluble sugar concentrations of nine plant species with differing levels of drought tolerance and 41 cassava varieties using high-performance liquid chromatography with evaporative light-scattering detector (HPLC-ELSD). Significantly high amounts of trehalose were identified in drought-tolerant crops cassava, Jatropha curcas, and castor bean (Ricinus communis). All cassava varieties tested contained high amounts of trehalose, although their concentrations varied from 0.23 to 1.29 mg·g(-1) fresh weight (FW), and the trehalose level was highly correlated with dehydration stress tolerance of detached leaves of the varieties. Moreover, the trehalose concentrations in cassava leaves increased 2.3-5.5 folds in response to osmotic stress simulated by 20% PEG 6000. Through database mining, 24 trehalose pathway genes, including 12 trehalose-6-phosphate synthases (TPS), 10 trehalose-6-phosphate phosphatases (TPP), and two trehalases were identified in cassava. Phylogenetic analysis indicated that there were four cassava TPS genes (MeTPS1-4) that were orthologous to the solely active TPS gene (AtTPS1 and OsTPS1) in Arabidopsis and rice, and a new TPP subfamily was identified in cassava, suggesting that the trehalose biosynthesis activities in cassava had potentially been enhanced in evolutionary history. RNA-seq analysis indicated that MeTPS1 was expressed at constitutionally high level before and after osmotic stress, while other trehalose pathway genes were either up-regulated or down-regulated, which may explain why cassava accumulated high level of trehalose under normal

  17. Mechanistic Insights on the Reductive Dehydroxylation Pathway for the Biosynthesis of Isoprenoids Promoted by the IspH Enzyme

    KAUST Repository

    Abdel-Azeim, Safwat

    2015-06-22

    Here, we report an integrated quantum mechanics/molecular mechanics (QM/MM) study of the bio-organometallic reaction pathway of the 2H+/2e- reduction of (E)-4-hydroxy-3-methylbut-2-enyl pyrophosphate (HMBPP) into the so called universal terpenoids precursors isopentenyl pyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP), promoted by the IspH enzyme. Our results support the viability of the bio-organometallic pathway from rotation of the OH group of HMBPP away from the [Fe4S4] cluster at the core of the catalytic site, to be engaged in a H-bond with Glu126. This rotation is synchronous with π-coordination of the C2=C3 double bond of HMBPP to the apical Fe atom of the [Fe4S4] cluster. Dehydroxylation of HMBPP is triggered by a proton transfer from Glu126 to the OH group of HMBPP. The reaction pathway is completed by competitive proton transfer from the terminal phosphate group to the C2 or C4 atom of HMBPP.

  18. Gene transcript profiles of the TIA biosynthetic pathway in response to ethylene and copper reveal their interactive role in modulating TIA biosynthesis in Catharanthus roseus.

    Science.gov (United States)

    Pan, Ya-Jie; Liu, Jia; Guo, Xiao-Rui; Zu, Yuan-Gang; Tang, Zhong-Hua

    2015-05-01

    Research on transcriptional regulation of terpenoid indole alkaloid (TIA) biosynthesis of the medicinal plant, Catharanthus roseus, has largely been focused on gene function and not clustering analysis of multiple genes at the transcript level. Here, more than ten key genes encoding key enzyme of alkaloid synthesis in TIA biosynthetic pathways were chosen to investigate the integrative responses to exogenous elicitor ethylene and copper (Cu) at both transcriptional and metabolic levels. The ethylene-induced gene transcripts in leaves and roots, respectively, were subjected to principal component analysis (PCA) and the results showed the overall expression of TIA pathway genes indicated as the Q value followed a standard normal distribution after ethylene treatments. Peak gene expression was at 15-30 μM of ethephon, and the pre-mature leaf had a higher Q value than the immature or mature leaf and root. Treatment with elicitor Cu found that Cu up-regulated overall TIA gene expression more in roots than in leaves. The combined effects of Cu and ethephon on TIA gene expression were stronger than their separate effects. It has been documented that TIA gene expression is tightly regulated by the transcriptional factor (TF) ethylene responsive factor (ERF) and mitogen-activated protein kinase (MAPK) cascade. The loading plot combination with correlation analysis for the genes of C. roseus showed that expression of the MPK gene correlated with strictosidine synthase (STR) and strictosidine b-D-glucosidase(SGD). In addition, ERF expression correlated with expression of secologanin synthase (SLS) and tryptophan decarboxylase (TDC), specifically in roots, whereas MPK and myelocytomatosis oncogene (MYC) correlated with STR and SGD genes. In conclusion, the ERF regulates the upstream pathway genes in response to heavy metal Cu mainly in C. roseus roots, while the MPK mainly participates in regulating the STR gene in response to ethylene in pre-mature leaf. Interestingly, the

  19. Mammalian cardiolipin biosynthesis.

    Science.gov (United States)

    Mejia, Edgard M; Nguyen, Hieu; Hatch, Grant M

    2014-04-01

    Cardiolipin is a major phospholipid in mitochondria and is involved in the generation of cellular energy in the form of ATP. In mammalian and eukaryotic cells it is synthesized via the cytidine-5'-diphosphate-1,2-diacyl-sn-glycerol phosphate pathway. This brief review will describe some of the more recent studies on mammalian cardiolipin biosynthesis and provide an overview of regulation of cardiolipin biosynthesis. In addition, the important role that this key phospholipid plays in disease processes including heart failure, diabetes, thyroid hormone disease and the genetic disease Barth Syndrome will be discussed. PMID:24144810

  20. In vitro characterization of the enzymes involved in TDP-D-forosamine biosynthesis in the spinosyn pathway of Saccharopolyspora spinosa.

    Science.gov (United States)

    Hong, Lin; Zhao, Zongbao; Melançon, Charles E; Zhang, Hua; Liu, Hung-wen

    2008-04-01

    Forosamine (4-dimethylamino)-2,3,4,6-tetradeoxy-beta-D-threo-hexopyranose) is a highly deoxygenated sugar component of several important natural products, including the potent yet environmentally benign insecticide spinosyns. To study D-forosamine biosynthesis, the five genes (spnO, N, Q, R, and S) from the spinosyn gene cluster thought to be involved in the conversion of TDP-4-keto-6-deoxy-D-glucose to TDP-D-forosamine were cloned and heterologously expressed, and the corresponding proteins were purified and their activities examined in vitro. Previous work demonstrated that SpnQ functions as a pyridoxamine 5'-monophosphate (PMP)-dependent 3-dehydrase which, in the presence of the cellular reductase pairs ferredoxin/ferredoxin reductase or flavodoxin/flavodoxin reductase, catalyzes C-3 deoxygenation of TDP-4-keto-2,6-dideoxy-D-glucose. It was also established that SpnR functions as a transaminase which converts the SpnQ product, TDP-4-keto-2,3,6-trideoxy-D-glucose, to TDP-4-amino-2,3,4,6-tetradeoxy-D-glucose. The results presented here provide a full account of the characterization of SpnR and SpnQ and reveal that SpnO and SpnN functions as a 2,3-dehydrase and a 3-ketoreductase, respectively. These two enzymes act sequentially to catalyze C-2 deoxygenation of TDP-4-keto-6-deoxy-D-glucose to form the SpnQ substrate, TDP-4-keto-2,6-dideoxy-D-glucose. Evidence has also been obtained to show that SpnS functions as the 4-dimethyltransferase that converts the SpnR product to TDP-D-forosamine. Thus, the biochemical functions of the five enzymes involved in TDP-D-forosamine formation have now been fully elucidated. The steady-state kinetic parameters for the SpnQ-catalyzed reaction have been determined, and the substrate specificities of SpnQ and SpnR have been explored. The implications of this work for natural product glycodiversification and comparative mechanistic analysis of SpnQ and related NDP-sugar 3-dehydrases E1 and ColD are discussed. PMID:18345667

  1. Possible genetical pathways for the biosynthesis of blood group mucopolysaccharides. Vox Sang 1959:4:97-119.

    Science.gov (United States)

    Watkins, W M; Morgan, W T

    1993-01-01

    This paper put forward possible biosynthetic pathways for the formation of the blood group A, B, H and Lewis antigens based on the limited knowledge of their chemistry and genetics that was available in 1959. The schemes proposed that genes at four independent loci ABO, HH, Lele and Sese interacted to give the five specificities A, B, H, Lea and Leb found in secretions and that the primary products of the blood group genes were not the antigens but enzymes that catalysed the sequential addition of single sugars to complete the determinants. PMID:7685971

  2. Gene expression profiling of lymphoblasts from autistic and nonaffected sib pairs: altered pathways in neuronal development and steroid biosynthesis.

    Directory of Open Access Journals (Sweden)

    Valerie W Hu

    Full Text Available Despite the identification of numerous autism susceptibility genes, the pathobiology of autism remains unknown. The present "case-control" study takes a global approach to understanding the molecular basis of autism spectrum disorders based upon large-scale gene expression profiling. DNA microarray analyses were conducted on lymphoblastoid cell lines from over 20 sib pairs in which one sibling had a diagnosis of autism and the other was not affected in order to identify biochemical and signaling pathways which are differentially regulated in cells from autistic and nonautistic siblings. Bioinformatics and gene ontological analyses of the data implicate genes which are involved in nervous system development, inflammation, and cytoskeletal organization, in addition to genes which may be relevant to gastrointestinal or other physiological symptoms often associated with autism. Moreover, the data further suggests that these processes may be modulated by cholesterol/steroid metabolism, especially at the level of androgenic hormones. Elevation of male hormones, in turn, has been suggested as a possible factor influencing susceptibility to autism, which affects approximately 4 times as many males as females. Preliminary metabolic profiling of steroid hormones in lymphoblastoid cell lines from several pairs of siblings reveals higher levels of testosterone in the autistic sibling, which is consistent with the increased expression of two genes involved in the steroidogenesis pathway. Global gene expression profiling of cultured cells from ASD probands thus serves as a window to underlying metabolic and signaling deficits that may be relevant to the pathobiology of autism.

  3. Characterization of SpnQ from the spinosyn biosynthetic pathway of Saccharopolyspora spinosa: mechanistic and evolutionary implications for C-3 deoxygenation in deoxysugar biosynthesis.

    Science.gov (United States)

    Hong, Lin; Zhao, Zongbao; Liu, Hung-wen

    2006-11-01

    The C-3 deoxygenation step in the biosynthesis of d-forosamine (4-N,N-dimethylamino-2,3,4,6-tetradeoxy-d-threo-hexopyranose), a constituent of spinosyn produced by Saccharopolyspora spinosa, was investigated. The spnQ gene, proposed to encode a TDP-4-keto-2,6-dideoxy-d-glucose 3-dehydratase was cloned and overexpressed in E. coli. Characterization of the purified enzyme established that it is a PMP and iron-sulfur containing enzyme which catalyzes the C-3 deoxygenation in a reductase-dependent manner similar to that of the previously well characterized hexose 3-dehydrase E1 from Yersinia pseudotuberculosis. However, unlike E1, which has evolved to work with a specific reductase partner present in its gene cluster, SpnQ lacks a specific reductase, and works efficiently with general cellular reductases ferredoxin/ferredoxin reductase or flavodoxin/flavodoxin reductase. SpnQ also catalyzes C-4 transamination in the absence of an electron transfer intermediary and in the presence of PLP and l-glutamate. Under the same conditions, both E1 and the related hexose 3-dehydrase, ColD, catalyze C-3 deoxygenation. Thus, SpnQ possesses important features which distinguish it from other well studied homologues, suggesting unique evolutionary pathways for each of the three hexose 3-dehydrases studied thus far. PMID:17076492

  4. Upregulated mRNA expression of desaturase and elongase, two enzymes involved in highly unsaturated fatty acids biosynthesis pathways during follicle maturation in zebrafish

    Directory of Open Access Journals (Sweden)

    Enyu Yee-Ling

    2008-11-01

    Full Text Available Abstract Background Although unsaturated fatty acids such as eicosapentaenoic acid (EPA, C20:5n-3, docosahexaenoic acid (DHA, C22:6n-3 and arachidonic acid (ARA, C20:4n-6, collectively known as the highly unsaturated fatty acids (HUFA, play pivotal roles in vertebrate reproduction, very little is known about their synthesis in the ovary. The zebrafish (Danio rerio display capability to synthesize all three HUFA via pathways involving desaturation and elongation of two precursors, the linoleic acid (LA, C18:2n-6 and linolenic acid (LNA, C18:3n-3. As a prerequisite to gain full understanding on the importance and regulation of ovarian HUFA synthesis, we described here the mRNA expression pattern of two enzymes; desaturase (fadsd6 and elongase (elovl5, involved in HUFA biosynthesis pathway, in different zebrafish ovarian follicle stages. Concurrently, the fatty acid profile of each follicle stage was also analyzed. Methods mRNA levels of fadsd6 and elovl5 in different ovarian follicle stages were determined by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR assays. For analysis of the ovarian follicular fatty acid composition, gas chromatography was used. Results Our results have shown that desaturase displayed significant upregulation in expression during the oocyte maturation stage. Expression of elongase was significantly highest in pre-vitellogenic follicles, followed by maturation stage. Fatty acid composition analysis of different ovarian follicle stages also showed that ARA level was significantly highest in pre-vitellogenic and matured follicles. DHA level was highest in both late vitellogenic and maturation stage. Conclusion Collectively, our findings seem to suggest the existence of a HUFA synthesis system, which could be responsible for the synthesis of HUFA to promote oocyte maturation and possibly ovulation processes. The many advantages of zebrafish as model system to understand folliculogenesis will be

  5. Effect of astaxanthin on human sperm capacitation.

    Science.gov (United States)

    Donà, Gabriella; Kožuh, Ivana; Brunati, Anna Maria; Andrisani, Alessandra; Ambrosini, Guido; Bonanni, Guglielmo; Ragazzi, Eugenio; Armanini, Decio; Clari, Giulio; Bordin, Luciana

    2013-06-01

    In order to be able to fertilize oocytes, human sperm must undergo a series of morphological and structural alterations, known as capacitation. It has been shown that the production of endogenous sperm reactive oxygen species (ROS) plays a key role in causing cells to undergo a massive acrosome reaction (AR). Astaxanthin (Asta), a photo-protective red pigment belonging to the carotenoid family, is recognized as having anti-oxidant, anti-cancer, anti-diabetic and anti-inflammatory properties and is present in many dietary supplements. This study evaluates the effect of Asta in a capacitating buffer which induces low ROS production and low percentages of acrosome-reacted cells (ARC). Sperm cells were incubated in the presence or absence of increasing concentrations of Asta or diamide (Diam) and analyzed for their ROS production, Tyr-phosphorylation (Tyr-P) pattern and percentages of ARC and non-viable cells (NVC). Results show that Asta ameliorated both sperm head Tyr-P and ARC values without affecting the ROS generation curve, whereas Diam succeeded in enhancing the Tyr-P level but only of the flagellum without increasing ARC values. It is suggested that Asta can be inserted in the membrane and therefore create capacitation-like membrane alteration which allow Tyr-P of the head. Once this has occurred, AR can take place and involves a higher numbers of cells. PMID:23736766

  6. Effect of Astaxanthin on Human Sperm Capacitation

    Directory of Open Access Journals (Sweden)

    Luciana Bordin

    2013-06-01

    Full Text Available In order to be able to fertilize oocytes, human sperm must undergo a series of morphological and structural alterations, known as capacitation. It has been shown that the production of endogenous sperm reactive oxygen species (ROS plays a key role in causing cells to undergo a massive acrosome reaction (AR. Astaxanthin (Asta, a photo-protective red pigment belonging to the carotenoid family, is recognized as having anti-oxidant, anti-cancer, anti-diabetic and anti-inflammatory properties and is present in many dietary supplements. This study evaluates the effect of Asta in a capacitating buffer which induces low ROS production and low percentages of acrosome-reacted cells (ARC. Sperm cells were incubated in the presence or absence of increasing concentrations of Asta or diamide (Diam and analyzed for their ROS production, Tyr-phosphorylation (Tyr-P pattern and percentages of ARC and non-viable cells (NVC. Results show that Asta ameliorated both sperm head Tyr-P and ARC values without affecting the ROS generation curve, whereas Diam succeeded in enhancing the Tyr-P level but only of the flagellum without increasing ARC values. It is suggested that Asta can be inserted in the membrane and therefore create capacitation-like membrane alteration which allow Tyr-P of the head. Once this has occurred, AR can take place and involves a higher numbers of cells.

  7. Chromatographic, NMR and vibrational spectroscopic investigations of astaxanthin esters: application to "Astaxanthin-rich shrimp oil" obtained from processing of Nordic shrimps.

    Science.gov (United States)

    Subramanian, B; Thibault, M-H; Djaoued, Y; Pelletier, C; Touaibia, M; Tchoukanova, N

    2015-11-01

    Astaxanthin (ASTX) is a keto carotenoid, which possesses a non-polar linear central conjugated chain and polar β-ionone rings with ketone and hydroxyl groups at the extreme ends. It is well known as a super anti-oxidant, and recent clinical studies have established its nutritional benefits. Although it occurs in several forms, including free molecule, crystalline, aggregates and various geometrical isomers, in nature it exists primarily in the form of esters. Marine animals accumulate ASTX from primary sources such as algae. Nordic shrimps (P. borealis), which are harvested widely in the Atlantic Ocean, form a major source of astaxanthin esters. "Astaxanthin-rich shrimp oil" was developed as a novel product in a shrimp processing plant in Eastern Canada. A compositional analysis of the shrimp oil was performed, with a view to possibly use it as a nutraceutical product for humans and animals. Astaxanthin-rich shrimp oil contains 50% MUFAs and 22% PUFAs, of which 20% are omega-3. In addition, the shrimp oil contains interesting amounts of EPA and DHA, with 10%/w and 8%/w, respectively. Astaxanthin concentrations varied between 400 and 1000 ppm, depending on the harvesting season of the shrimp. Astaxanthin and its esters were isolated from the oil and analysed by NMR, FTIR and Micro-Raman spectroscopy. Astaxanthin mono- and diesters were synthesized and used as standards for the analysis of astaxanthin-rich shrimp oil. NMR and vibrational spectroscopy techniques were successfully used for the rapid characterization of monoesters and diesters of astaxanthin. Raman spectroscopy provided important intermolecular interactions present in the esterified forms of astaxanthin molecules. Also discussed in this paper is the use of NMR, FTIR and Micro-Raman spectroscopy for the detection of astaxanthin esters in shrimp oil. PMID:26393239

  8. Astaxanthin: Sources, Extraction, Stability, Biological Activities and Its Commercial Applications—A Review

    Directory of Open Access Journals (Sweden)

    Ranga Rao Ambati

    2014-01-01

    Full Text Available There is currently much interest in biological active compounds derived from natural resources, especially compounds that can efficiently act on molecular targets, which are involved in various diseases. Astaxanthin (3,3′-dihydroxy-β, β′-carotene-4,4′-dione is a xanthophyll carotenoid, contained in Haematococcus pluvialis, Chlorella zofingiensis, Chlorococcum, and Phaffia rhodozyma. It accumulates up to 3.8% on the dry weight basis in H. pluvialis. Our recent published data on astaxanthin extraction, analysis, stability studies, and its biological activities results were added to this review paper. Based on our results and current literature, astaxanthin showed potential biological activity in in vitro and in vivo models. These studies emphasize the influence of astaxanthin and its beneficial effects on the metabolism in animals and humans. Bioavailability of astaxanthin in animals was enhanced after feeding Haematococcus biomass as a source of astaxanthin. Astaxanthin, used as a nutritional supplement, antioxidant and anticancer agent, prevents diabetes, cardiovascular diseases, and neurodegenerative disorders, and also stimulates immunization. Astaxanthin products are used for commercial applications in the dosage forms as tablets, capsules, syrups, oils, soft gels, creams, biomass and granulated powders. Astaxanthin patent applications are available in food, feed and nutraceutical applications. The current review provides up-to-date information on astaxanthin sources, extraction, analysis, stability, biological activities, health benefits and special attention paid to its commercial applications.

  9. Flower color alteration in Lotus japonicus by modification of the carotenoid biosynthetic pathway.

    Science.gov (United States)

    Suzuki, Sakae; Nishihara, Masahiro; Nakatsuka, Takashi; Misawa, Norihiko; Ogiwara, Isao; Yamamura, Saburo

    2007-07-01

    To establish a model system for alteration of flower color by carotenoid pigments, we modified the carotenoid biosynthesis pathway of Lotus japonicus using overexpression of the crtW gene isolated from marine bacteria Agrobacterium aurantiacum and encoding beta-carotene ketolase (4,4'-beta-oxygenase) for the production of pink to red color ketocarotenoids. The crtW gene with the transit peptide sequence of the pea Rubisco small subunit under the regulation of the CaMV35S promoter was introduced to L. japonicus. In most of the resulting transgenic plants, the color of flower petals changed from original light yellow to deep yellow or orange while otherwise exhibiting normal phenotype. HPLC and TLC analyses revealed that leaves and flower petals of these plants accumulated novel carotenoids, believed to be ketocarotenoids consisting of including astaxanthin, adonixanthin, canthaxanthin and echinenone. Results indicated that modification of the carotenoid biosynthesis pathway is a means of altering flower color in ornamental crops. PMID:17265153

  10. Green Approaches to Extract Astaxanthin from Shrimp Waste

    DEFF Research Database (Denmark)

    Razi Parjikolaei, Behnaz; Errico, Massimiliano; El-Houri, Rime Bahij;

    2016-01-01

    , according to the economic analysis, the green solvents showed lower capital and operating costs. Extraction with methyl ester of sunflower oil was found to be the more efficient green solvent process investigated with respect to production rate and unit cost of concentrated astaxanthin (155 ppm)....

  11. Kinetic model for astaxanthin aggregation in water-methanol mixtures

    Science.gov (United States)

    Giovannetti, Rita; Alibabaei, Leila; Pucciarelli, Filippo

    2009-07-01

    The aggregation of astaxanthin in hydrated methanol was kinetically studied in the temperature range from 10 °C to 50 °C, at different astaxanthin concentrations and solvent composition. A kinetic model for the formation and transformation of astaxanthin aggregated has been proposed. Spectrophotometric studies showed that monomeric astaxanthin decayed to H-aggregates that after-wards formed J-aggregates when water content was 50% and the temperature lower than 20 °C; at higher temperatures, very stable J-aggregates were formed directly. Monomer formed very stable H-aggregates when the water content was greater than 60%; in these conditions H-aggregates decayed into J-aggregates only when the temperature was at least 50 °C. Through these findings it was possible to establish that the aggregation reactions took place through a two steps consecutive reaction with first order kinetic constants and that the values of these depended on the solvent composition and temperature.

  12. Multispectral Image Analysis for Robust Prediction of Astaxanthin Coating

    DEFF Research Database (Denmark)

    Ljungqvist, Martin Georg; Frosch, Stina; Nielsen, Michael Engelbrecht;

    2013-01-01

    synthetic astaxanthin in combination with four different recipes of feed pellets. We used a VideometerLab with 20 spectral bands in the range of 385-1050 nm. We used linear discriminant analysis and sparse linear discriminant analysis for classification and variable selection. We used partial least squares...

  13. Identification and characterization of a novel C20-elongase gene from the marine microalgae, Pavlova viridis, and its use for the reconstitution of two pathways of long-chain polyunsatured fatty acids biosynthesis in Saccharomyces cerevisiae.

    Science.gov (United States)

    Shi, Tonglei; Yu, Aiqun; Li, Ming; Zhang, Meng; Xing, Laijun; Li, Mingchun

    2013-08-01

    The marine microalga, Pavlova viridis, contains long-chain polyunsatured fatty acids including eicosapentaenoic acid (EPA, 20:5n-3) and docosapentaenoic acid (DPA, 22:5n-3). A full-length cDNA sequence, pvelo5, was isolated from P. viridis. From sequence alignment, the gene was homologous to fatty acyl elongases from other organisms. Heterologous expression of pvelo5 in Saccharomyces cerevisiae confirmed that it encoded a specific C20-elongase within the n-3 and n-6 pathways. Elongation activity was confined exclusively to EPA and arachidonic acid (20:4n-6). GC analysis indicated that pvelo5 could co-express with other genes for biosynthesis to reconstitute the Δ8 and Δ6 pathways. Real-time PCR results and fatty acid analysis demonstrated that long-chain polyunsatured fatty acids production by the Δ8 pathway might be more effective than that by the Δ6 pathway. PMID:23546943

  14. Oxidative stress and astaxanthin: The novel supernutrient carotenoid

    Directory of Open Access Journals (Sweden)

    Sasmita Biswal

    2014-01-01

    Full Text Available Background: Oxidative stress and inflammation leads to, generation and overproduction of the reactive oxygen species and reactive nitrogen species and hence are responsible for many diseases such as Alzheimer′s disease, Parkinson′s disease, diabetes mellitus, rheumatoid arthritis, and neurodegenerative motor neuron diseases. Antioxidants are found in varying amounts in vegetables, fruits, grain cereals, eggs, meat, legumes and nuts. However, there is always a search for antioxidants that can quench and breakup the chain of generation of free-radicals. Aims: Astaxanthin, a ketocarotenoid, has exceptional antioxidant activity and hence can be used for prevention of cardiovascular diseases, inflammatory and neurodegenerative diseases, boosting of the immune system, anti-Helicobacter pylori activity, and cataract prevention. Hence, an attempt has performed in this review to compile data on astaxanthin and its several diverse applications over the last decade with an aim to escalate the intense interest in undertaking new research on this natural fascinating molecule. Materials and Methods: A literature search using astaxanthin and antioxidants as keywords using Google as the search engine was done and the data obtained were compiled and presented. Results and Conclusions: Astaxanthin can be a great supplement for everyone in enhancing immunity, preventing a myriad of diseases in our hectic lifestyle by providing more energy, reducing oxidative damage, producing clarity of vision as well as protection from the harmful ultraviolet rays of the sun! Further the immunomodulatory, antioxidative, and antiinflammatory activity of astaxanthin a bioactive natural supernutrient carotenoid may be very important to human health in treating many such untreatable diseases.

  15. Taking control over control: use of product sensing in single cells to remove flux control at key enzymes in biosynthesis pathways.

    Science.gov (United States)

    Schendzielorz, Georg; Dippong, Martin; Grünberger, Alexander; Kohlheyer, Dietrich; Yoshida, Ayako; Binder, Stephan; Nishiyama, Chiharu; Nishiyama, Makoto; Bott, Michael; Eggeling, Lothar

    2014-01-17

    Enzymes initiating the biosynthesis of cellular building blocks are frequently inhibited by the end-product of the respective pathway. Here we present an approach to rapidly generate sets of enzymes overriding this control. It is based on the in vivo detection of the desired end-product in single cells using a genetically encoded sensor. The sensor transmits intracellular product concentrations into a graded optical output, thus enabling ultrahigh-throughput screens by FACS. We randomly mutagenized plasmid-encoded ArgB of Corynebacterium glutamicum and screened the library in a strain carrying the sensor pSenLys-Spc, which detects l-lysine, l-arginine and l-histidine. Six of the resulting N-acetyl-l-glutamate kinase proteins were further developed and characterized and found to be at least 20-fold less sensitive toward l-arginine inhibition than the wild-type enzyme. Overexpression of the mutein ArgB-K47H-V65A in C. glutamicumΔargR led to the accumulation of 34 mM l-arginine in the culture medium. We also screened mutant libraries of lysC-encoded aspartate kinase and hisG-encoded ATP phosphoribosyltransferase. We isolated 11 LysC muteins, enabling up to 45 mM l-lysine accumulation, and 13 HisG muteins, enabling up to 17 mM l-histidine accumulation. These results demonstrate that in vivo screening of enzyme libraries by using metabolite sensors is extremely well suited to identify high-performance muteins required for overproduction. PMID:23829416

  16. Towards Elucidating Carnosic Acid Biosynthesis in Lamiaceae: Functional Characterization of the Three First Steps of the Pathway in Salvia fruticosa and Rosmarinus officinalis.

    Science.gov (United States)

    Božić, Dragana; Papaefthimiou, Dimitra; Brückner, Kathleen; de Vos, Ric C H; Tsoleridis, Constantinos A; Katsarou, Dimitra; Papanikolaou, Antigoni; Pateraki, Irini; Chatzopoulou, Fani M; Dimitriadou, Eleni; Kostas, Stefanos; Manzano, David; Scheler, Ulschan; Ferrer, Albert; Tissier, Alain; Makris, Antonios M; Kampranis, Sotirios C; Kanellis, Angelos K

    2015-01-01

    Carnosic acid (CA) is a phenolic diterpene with anti-tumour, anti-diabetic, antibacterial and neuroprotective properties that is produced by a number of species from several genera of the Lamiaceae family, including Salvia fruticosa (Cretan sage) and Rosmarinus officinalis (Rosemary). To elucidate CA biosynthesis, glandular trichome transcriptome data of S. fruticosa were mined for terpene synthase genes. Two putative diterpene synthase genes, namely SfCPS and SfKSL, showing similarities to copalyl diphosphate synthase and kaurene synthase-like genes, respectively, were isolated and functionally characterized. Recombinant expression in Escherichia coli followed by in vitro enzyme activity assays confirmed that SfCPS is a copalyl diphosphate synthase. Coupling of SfCPS with SfKSL, both in vitro and in yeast, resulted in the synthesis miltiradiene, as confirmed by 1D and 2D NMR analyses (1H, 13C, DEPT, COSY H-H, HMQC and HMBC). Coupled transient in vivo assays of SfCPS and SfKSL in Nicotiana benthamiana further confirmed production of miltiradiene in planta. To elucidate the subsequent biosynthetic step, RNA-Seq data of S. fruticosa and R. officinalis were searched for cytochrome P450 (CYP) encoding genes potentially involved in the synthesis of the first phenolic compound in the CA pathway, ferruginol. Three candidate genes were selected, SfFS, RoFS1 and RoFS2. Using yeast and N. benthamiana expression systems, all three where confirmed to be coding for ferruginol synthases, thus revealing the enzymatic activities responsible for the first three steps leading to CA in two Lamiaceae genera. PMID:26020634

  17. Astaxanthin Improves Stem Cell Potency via an Increase in the Proliferation of Neural Progenitor Cells

    OpenAIRE

    Yung-Hyun Choi; Byung-Woo Kim; Woobong Choi; Jong-Hwan Lee; Wun-Jae Kim; Soo-Wan Nam; Jeong-Hwan Kim

    2010-01-01

    The present study was designed to investigate the question of whether or not astaxanthin improves stem cell potency via an increase in proliferation of neural progenitor cells (NPCs). Treatment with astaxanthin significantly increased proliferation and colony formation of NPCs. For identification of possible activated signaling molecules involved in active cell proliferation occurring after astaxanthin treatment, total protein levels of several proliferation-related proteins, and expression l...

  18. Effects of spray-drying and storage on astaxanthin content of Haematococcus pluvialis biomass

    OpenAIRE

    Raposo, Maria Filomena J.; Morais, Alcina M. M. B.; Morais, Rui M. S. C.

    2012-01-01

    The main objective of this study was to evaluate the stability of astaxanthin after drying and storage at different conditions during a 9-week period. Recovery of astaxanthin was evaluated by extracting pigments from the dried powders and analysing extracts by HPLC. The powders obtained were stored under different conditions of temperature and oxygen level and the effects on the degradation of astaxanthin were examined. Under the experimental conditions conducted in this study, the drying tem...

  19. Astaxanthin Synthesis by Yeast Xanthophyllomyces dendrorhous and its Mutants on Media Based on Plant Extracts

    OpenAIRE

    Stachowiak, Barbara

    2012-01-01

    The study evaluated the effect of media based on plant extracts: potato, carrot and barley malt broth, on growth and astaxanthin synthesis by yeast Xanthophyllomyces dendrorhous DSM 5626 and its mutants. The carrot medium promoted carotenogenesis most effectively. In cultures on this medium the highest volumetric and cellular concentrations of astaxanthin were recorded for four out of five tested strains. Also the share of astaxanthin in the total carotenoids produced by the tested strains wa...

  20. Pigmentation of salmonid - a comparison of astaxanthin and cantaxanthin as pigment sources for rainbow trout

    OpenAIRE

    Torrissen, Ole

    1985-01-01

    Rainbow trout were fed a diet supplemented with astaxanthin and cantaxanthin. The ratios of astaxanthin to cantaxanthin were determined in plasma, faeces and flesh. During 65 days of feeding the flesh reached a level of 4.5 mg carotenoids/kg. A linear relationship between growth and carotenoid level was found for growths below 150g/65 days. Astaxanthin seemed to be absorbed more readily from the diet and also deposited at a higher ratio than cantaxanthin in the flesh. Pyl...

  1. Studies on optimization of nitrogen sources for astaxanthin production by Phaffia rhodozyma *

    OpenAIRE

    Ni, Hui; Chen, Qi-he; Ruan, Hui; Yang, Yuan-Fan; Li, Li-jun; Wu, Guang-bin; Hu, Yang; He, Guo-qing

    2007-01-01

    Fermentation of Phaffia rhodozyma is a major method for producing astaxanthin, an important pigment with industrial and pharmaceutical application. To improve astaxanthin productivity, single factor and mixture design experiments were used to investigate the effects of nitrogen source on Phaffia rhodozyma cultivation and astaxanthin production. Results of single factor experiments showed nitrogen source could significantly affect P. rhodozyma cultivation with respect to carbon source utilizat...

  2. Astaxanthin from Haematococcus pluvialis Prevents Oxidative Stress on Human Endothelial Cells without Toxicity

    OpenAIRE

    Philippe Régnier; Jorge Bastias; Violeta Rodriguez-Ruiz; Noelia Caballero-Casero; Carmen Caballo; Dolores Sicilia; Axelle Fuentes; Murielle Maire; Michel Crepin; Didier Letourneur; Virginie Gueguen; Soledad Rubio; Graciela Pavon-Djavid

    2015-01-01

    Astaxanthin, a powerful antioxidant, is a good candidate for the prevention of intracellular oxidative stress. The aim of the study was to compare the antioxidant activity of astaxanthin present in two natural extracts from Haematococcus pluvialis, a microalgae strain, with that of synthetic astaxanthin. Natural extracts were obtained either by solvent or supercritical extraction methods. UV, HPLC-DAD and (HPLC-(atmospheric pressure chemical ionization (APCI)+)/ion trap-MS) characterizations ...

  3. Chlorella zofingiensis as an Alternative Microalgal Producer of Astaxanthin: Biology and Industrial Potential

    OpenAIRE

    Jin Liu; Zheng Sun; Henri Gerken; Zheng Liu; Yue Jiang; Feng Chen

    2014-01-01

    Astaxanthin (3,3′-dihydroxy-β,β-carotene-4,4′-dione), a high-value ketocarotenoid with a broad range of applications in food, feed, nutraceutical, and pharmaceutical industries, has been gaining great attention from science and the public in recent years. The green microalgae Haematococcus pluvialis and Chlorella zofingiensis represent the most promising producers of natural astaxanthin. Although H. pluvialis possesses the highest intracellular astaxanthin content and is now believed to be a ...

  4. Effect of Different Carbon Source on Expression of Carotenogenic Genes and Astaxanthin Production in Xanthophyllomyces dendrorhous

    OpenAIRE

    Wei Wu; Xin Yu

    2013-01-01

    The present research gives an insight into astaxanthin production, as well as transcription differences of four key carotenogenic genes, in Xanthophyllomyces dendrorhous when cultured with various carbon sources and soybean oil as co-substrates. Glucose was found to be the carbon source with best culture growth and astaxanthin production and the addition of 2% (v/v) soybean oil resulted in even higher astaxanthin producing. In addition, four carotenogenic genes encoding geranylgeranyl diphosp...

  5. Astaxanthin prevents pulmonary fibrosis by promoting myofibroblast apoptosis dependent on Drp1-mediated mitochondrial fission

    OpenAIRE

    Zhang, Jinjin; Xu, Pan; Wang, Youlei; Wang, Meirong; Li, Hongbo; Lin, Shengcui; Mao, Cuiping; Wang, Bingsi; Song, Xiaodong; LV, CHANGJUN

    2015-01-01

    Promotion of myofibroblast apoptosis is a potential therapeutic strategy for pulmonary fibrosis. This study investigated the antifibrotic effect of astaxanthin on the promotion of myofibroblast apoptosis based on dynamin-related protein-1 (Drp1)-mediated mitochondrial fission in vivo and in vitro. Results showed that astaxanthin can inhibit lung parenchymal distortion and collagen deposition, as well as promote myofibroblast apoptosis. Astaxanthin demonstrated pro-apoptotic function in myofib...

  6. Astaxanthin Accumulation in the Green Alga Haematococcus pluvialis: Effects of Cultivation Parameters

    Institute of Scientific and Technical Information of China (English)

    Ping He; James Duncan; James Barber

    2007-01-01

    The green alga, Haematococcus pluvialis Flotow is used as a source of the ketocarotenoid astaxanthin for application in fish aquaculture, pharmaceutical and cosmetic industries. Cells of the green alga were induced by the application of different light and starvation conditions to evaluate the effect in astaxanthin accumulate. The condiphosphate starvation. The results show that stresses applied in culture, which interfere with cell division, trigger the accumulation of astaxanthin. Notably, sulfur starvation results in a massive accumulation of this commercially important carotenoid.

  7. Organization of Astaxanthin within Oil Bodies of Haematococcus pluvialis Studied with Polarization-Dependent Harmonic Generation Microscopy

    OpenAIRE

    Tokarz, Danielle; Cisek, Richard; El-Ansari, Omar; Espie, George S.; Fekl, Ulrich; Barzda, Virginijus

    2014-01-01

    Nonlinear optical microscopy was used to image the localization of astaxanthin accumulation in the green alga, Haematococcus pluvialis. Polarization-in, polarization-out (PIPO) second harmonic generation (SHG) and third harmonic generation (THG) microscopy was applied to study the crystalline organization of astaxanthin molecules in light-stressed H. pluvialis in vivo. Since astaxanthin readily forms H- and J-aggregates in aqueous solutions, PIPO THG studies of astaxanthin aggregates containe...

  8. Astaxanthin Production by Freshwater Microalgae Chlorella sorokiniana and Marine Microalgae Tetraselmis sp.

    OpenAIRE

    Shaza Eva Mohamad; Rinugah Raman

    2012-01-01

    There are numerous commercial applications of microalgae nowadays owing to their vast biotechnological and economical potential. Indisputably, astaxanthin is one of the high value product synthesized by microalgae and is achieving commercial success. Astaxanthin is a keto-carotenoid pigment found in many aquatic animals including microalgae. Astaxanthin cannot be synthesized by animals and provided in the diet is compulsory. In this study, the production of astaxanthin by the freshwater micro...

  9. Determination of astaxanthin and astaxanthin esters in the microalgae Haematococcus pluvialis by LC-(APCI)MS and characterization of predominant carotenoid isomers by NMR spectroscopy.

    Science.gov (United States)

    Holtin, Karsten; Kuehnle, Maximilian; Rehbein, Jens; Schuler, Paul; Nicholson, Graeme; Albert, Klaus

    2009-11-01

    The oily product ZANTHIN consists of natural astaxanthin, which is manufactured from the microalgae Haematococcus pluvialis by supercritical CO(2) extraction. An HPLC method was developed to separate all of the components of the complex astaxanthin extract using a C(30) column. The separation resulted in different isomers of astaxanthin accompanied by two other carotenoids. The main component consisted of astaxanthin singly esterified with several different fatty acids. C18:3, C18:2, C18:1 and C16:0 were identified as the most commonly occurring fatty acids. Doubly esterified astaxanthin was also found, although in lower concentrations compared to singly esterified astaxanthin. After performing a detailed fatty acid analysis by GC-MS, the peaks from the extract were assigned via HPLC-MS. A trans to cis transmutation of the all-trans compound was performed by thermal treatment in order to obtain an enrichment of cis isomers as the basis for unambiguous identification via NMR experiments. The all-trans as well as the 9- and 13-cis isomers of astaxanthin were characterized in detail by UV/Vis, (1)H, and (1)H,(1)H COSY NMR spectroscopy. PMID:19466394

  10. Optimization of acidic extraction of astaxanthin from Phaffia rhodozyma

    Institute of Scientific and Technical Information of China (English)

    Hui NI; Qi-he CHEN; Guo-qing HE; Guang-bin WU; Yuan-fan YANG

    2008-01-01

    Optimization of a process for extracting astaxanthin from Phaffia rhodozyma by acidic method was investigated,regarding several extraction factors such as acids, organic solvents, temperature and time. Fractional factorial design, central composite design and response surface methodology were used to derive a statistically optimal model, which corresponded to the following optimal condition: concentration of lactic acid at 5.55 mol/L, ratio of ethanol to yeast dry weight at 20.25 ml/g, temperature for cell-disruption at 30 ℃, and extraction time for 3 min. Under this condition, astaxanthin and the total carotenoids could be extracted in amounts of 1294.7 μg/g and 1516.0 μg/g, respectively. This acidic method has advantages such as high extraction efficiency, low chemical toxicity and no special requirement of instruments. Therefore, it might be a more feasible and practical method for industrial practice.

  11. Multiple Mechanisms of Anti-Cancer Effects Exerted by Astaxanthin

    OpenAIRE

    Li Zhang; Handong Wang

    2015-01-01

    Astaxanthin (ATX) is a xanthophyll carotenoid which has been approved by the United States Food and Drug Administration (USFDA) as food colorant in animal and fish feed. It is widely found in algae and aquatic animals and has powerful anti-oxidative activity. Previous studies have revealed that ATX, with its anti-oxidative property, is beneficial as a therapeutic agent for various diseases without any side effects or toxicity. In addition, ATX also shows preclinical anti-tumor efficacy both i...

  12. Astaxanthin : a putative modulator of DNA damage and repair

    OpenAIRE

    2010-01-01

    Dietary antioxidants are thought to be beneficial for human health. They can prevent damage to biomolecules such as DNA by removing free radicals and consequently prevent oxidative stress. However, several large scale intervention studies have found no beneficial effects or even harmful effects of antioxidant supplementation. More studies are therefore needed to sort out whether, how or when antioxidants improve health. Astaxanthin is a marine carotenoid synthesised by algae, which gives s...

  13. Preparation of Astaxanthin Nanodispersions Using Gelatin-Based Stabilizer Systems

    OpenAIRE

    Navideh Anarjan; Imededdine Arbi Nehdi; Hassen Mohamed Sbihi; Saud Ibrahim Al-Resayes; Hoda Jafarizadeh Malmiri; Chin Ping Tan

    2014-01-01

    The incorporation of lipophilic nutrients, such as astaxanthin (a fat soluble carotenoid) in nanodispersion systems can either increase the water solubility, stability and bioavailability or widen their applications in aqueous food and pharmaceutical formulations. In this research, gelatin and its combinations with sucrose oleate as a small molecular emulsifier, sodium caseinate (SC) as a protein and gum Arabic as a polysaccharide were used as stabilizer systems in the formation of astaxanthi...

  14. Multi-spectral Image Analysis for Astaxanthin Coating Classification

    DEFF Research Database (Denmark)

    Ljungqvist, Martin Georg; Ersbøll, Bjarne Kjær; Nielsen, Michael Engelbrecht;

    2011-01-01

    Industrial quality inspection using image analysis on astaxanthin coating in aquaculture feed pellets is of great importance for automatic production control. In this study multi-spectral image analysis of pellets was performed using LDA, QDA, SNV and PCA on pixel level and mean value of pixels for...... each pellet. Classication using LDA or QDA on pellet mean or median values showed better results than using the pixel values or PCA....

  15. Production of astaxanthin from cellulosic biomass sugars by mutants of the yeast Phaffia rhodozyma

    Science.gov (United States)

    Astaxanthin is a carotenoid of high value to the aquaculture, nutraceutical, and pharmaceutical industries. Three mutant strains of the astaxanthin-producing yeast Phaffia rhodozyma, which were derived from the parent strain ATCC 24202 (UCD 67-210) and designated JTM166, JTM185, and SSM19, were test...

  16. Purification of Astaxanthin from Mutant of Phaffia rhodozyma JH-82 Which Isolated from Forests Trees of Iran

    OpenAIRE

    Shokufeh Golkhoo; Fatemeh Barantalab; Ali Reza Ahmadi; Zuhair Muhammad Hassan

    2007-01-01

    Astaxanthin have been extracted and purified from mutant isolate of Phaffia rhodozyma JH-82. Purified astaxanthin was identified by spectrophotometric, TLC and HPLC analysis and were compared with synthetic astaxanthin. Results of TLC analysis indicated that isolate of P. rhodozyma JH-82 were able to produce nine different carotenoids and high level of carotenoids was belong to astaxanthin. Results of this study for pure astaxanthin production indicated that mutant of JH-82 of P. rhodoz...

  17. Scientific Opinion on the safety and efficacy of synthetic astaxanthin as feed additive for salmon and trout, other fish, ornamental fish, crustaceans and ornamental birds

    OpenAIRE

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP)

    2014-01-01

    Astaxanthin is a pigmenting carotenoid occurring naturally in plankton, crustaceans and fish. The astaxanthin under assessment is of synthetic origin. The FEEDAP Panel considers synthetic astaxanthin safe for salmonids up to 100 mg/kg complete diet. The conclusion on the safety of astaxanthin for salmonids can be extrapolated to other fish and ornamental fish at the same dose. Dietary concentrations of up to 100 mg astaxanthin/kg feed are safe for crustaceans. The FEEDAP Panel could not concl...

  18. [Characterization and evaluation of an astaxanthin over-producing Phaffia rhodozyma].

    Science.gov (United States)

    Ni, Hui; Hong, Qinglin; Xiao, Anfeng; Li, Lijun; Cai, Huinong; Su, Wenjin

    2011-07-01

    We evaluated an astaxanthin overproducing Phaffia rhodozyma JMU-MVP14, and developed astaxanthin high-yielding fermentation process. We analyzed several fermentation parameters, i.e., biomass, astaxanthin and total carotenoids content to compare the characteristics of P rhodozyma JMU-MVP14 and the original strain through flask fermentation experiments. We conducted batch and fed-batch fermentation experiments in 7 L fermentor to investigate the effects of pH controlling models and feeding medium compositions on the production of astaxanthin. We further evaluated the capability and practical value of P rhodozyma JMU-MVP14 by fed-batch cultivation in the 1 m3 fermentor. Flask fermentation experiments revealed that P. rhodozyma JMU-MVP14 produced high yield of astaxanthin and carotenoids with specific productivity of astaxanthin and specific productivity of total carotenoids of 6.01 mg/g and 10.38 mg/g. Results of batch culture experiments in the 7 L fermentor showed that controlling the pH by ammonia auto-feeding was better than discontinuously adjusting pH value at 6.0 with regard to the high productivities of biomasses and astaxanthin. This P. rhodozyma strain synthesized astaxanthin partially linked to the growth with the Ks and pmax of 0.20 h ' and 21.73 g/L, respectively. Results of batch-fed fermentations in 7 L fermentor indicated that the complex feeding medium consisted of 50% glucose, 0.5% yeast extract and 0.3% corn steep syrup had lower astaxanthin productivity than the simple feeding medium containing only 50% glucose, which produced biomass, volumetric productivity of astaxanthin, volumetric productivity of total carotenoids, specific productivity of astaxanthin and total carotenoids at 32.81 g/L, 155.99 mg/L, 4.94 mg/g, 399.99 mg/L and 12.19 mg/g, respectively. As fed-batch cultured in 1 m3 fermentor, P rhodozyma JMU-MVP14 yielded 85.11 g/L of biomass, 279.96 mg/L of volumetric productivity of astaxanthin, 618.01 mg/L of volumetric productivity of

  19. Lignin biosynthesis and its molecular regulation

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Lignin biosynthesis has become increasingly highlighted because it plays an important role in the growth and development of plant, in the systematic evolution of plant and in the human life. Due to the progress in the field of lignin studies in recent years, the lignin biosynthesis pathway has been 修订日期:. Here we discuss some genetic engineering approaches on lignin biosynthesis, and conceive strategy to regulate lignin biosynthesis in order to use lignin resource more efficiently in agricultural and industrial productions.

  20. Propiconazole enhanced hepatic cell proliferation is associated with dysregulation of the cholesterol biosynthesis pathway leading to activation of Erk1/2 through Ras famesylation

    Science.gov (United States)

    Propiconazole is a mouse hepatotumorigenic fungicide designed to inhibit CYP51, a key enzyme in the biosynthesis of ergosterol in fungi and is widely used in agriculture to prevent fungal growth. Metabolomic studies in mice revealed that propiconazole increased levels of hepatic ...

  1. Antibacterial Targets in Fatty Acid Biosynthesis

    OpenAIRE

    Wright, H. Tonie; Reynolds, Kevin A.

    2007-01-01

    The fatty acid biosynthesis pathway is an attractive but still largely unexploited target for development of new anti-bacterial agents. The extended use of the anti-tuberculosis drug isoniazid and the antiseptic triclosan, which are inhibitors of fatty acid biosynthesis, validates this pathway as a target for anti-bacterial development. Differences in subcellular organization of the bacterial and eukaryotic multi-enzyme fatty acid synthase systems offer the prospect of inhibitors with host vs...

  2. The Evolution of Aflatoxin Biosynthesis

    Science.gov (United States)

    The biosynthesis of aflatoxin (AF) involves over 20 enzymatic reactions in a complex polyketide pathway that converts acetate and malonate to the intermediates sterigmatocystin (ST) and O-methylsterigmatocysin (OMST), the respective penultimate and ultimate precursors of AF. Although ST, OMST, and ...

  3. Towards Elucidating Carnosic Acid Biosynthesis in Lamiaceae: Funtional Characterization of the Three First Steps of the Pathway in Slavia Fruicosa and Rosmarinus officinalis

    OpenAIRE

    Bozic, D.; Papaefthimiou, D.; Brückner, K.; De Vos; Tsoleridis, C.A.; Katsarou, D.; Papanikolaou, A; Pateraki, I.; Chatzopoulou, F.M.; Dimitriadou, E.; Kostas, S.; Manzano, D.; Scheler, U.; Ferrer, A.(Instituto de Física Corpuscular (IFIC), Departamento de Física Atómica, Molecular y Nuclear, Departamento de Ingeniería Electrónica, Instituto de Microelectrónica de Barcelona (IMB-CNM), University of Valencia, CSIC, Valencia, Spain); Tissier, A.

    2015-01-01

    Carnosic acid (CA) is a phenolic diterpene with anti-tumour, anti-diabetic, antibacterial and neuroprotective properties that is produced by a number of species from several genera of the Lamiaceae family, including Salvia fruticosa (Cretan sage) and Rosmarinus officinalis (Rosemary). To elucidate CA biosynthesis, glandular trichome transcriptome data of S. fruticosa were mined for terpene synthase genes. Two putative diterpene synthase genes, namely SfCPSand SfKSL, showing similarities to co...

  4. A decade of molecular understanding of withanolide biosynthesis and in vitro studies in Withania somnifera (L.) Dunal: Prospects and perspectives for pathway engineering

    OpenAIRE

    Niha eDhar; Sumeer eRazdan; Satiander eRana; Wajid Waheed Bhat; Ram eVishwakarma; Surrinder K Lattoo

    2015-01-01

    Withania somnifera, a multipurpose medicinal plant is a rich reservoir of pharmaceutically active triterpenoids that are steroidal lactones known as withanolides. Though the plant has been well characterized in terms of phytochemical profiles as well as pharmaceutical activities, limited attempts have been made to decipher the biosynthetic route and identification of key regulatory genes involved in withanolide biosynthesis. This scenario limits biotechnological interventions for enhanced pro...

  5. A Decade of Molecular Understanding of Withanolide Biosynthesis and In vitro Studies in Withania somnifera (L.) Dunal: Prospects and Perspectives for Pathway Engineering

    OpenAIRE

    Dhar, Niha; Razdan, Sumeer; Rana, Satiander; Bhat, Wajid W.; Vishwakarma, Ram; Surrinder K Lattoo

    2015-01-01

    Withania somnifera, a multipurpose medicinal plant is a rich reservoir of pharmaceutically active triterpenoids that are steroidal lactones known as withanolides. Though the plant has been well-characterized in terms of phytochemical profiles as well as pharmaceutical activities, limited attempts have been made to decipher the biosynthetic route and identification of key regulatory genes involved in withanolide biosynthesis. This scenario limits biotechnological interventions for enhanced pro...

  6. Chlorella zofingiensis as an Alternative Microalgal Producer of Astaxanthin: Biology and Industrial Potential

    Directory of Open Access Journals (Sweden)

    Jin Liu

    2014-06-01

    Full Text Available Astaxanthin (3,3′-dihydroxy-β,β-carotene-4,4′-dione, a high-value ketocarotenoid with a broad range of applications in food, feed, nutraceutical, and pharmaceutical industries, has been gaining great attention from science and the public in recent years. The green microalgae Haematococcus pluvialis and Chlorella zofingiensis represent the most promising producers of natural astaxanthin. Although H. pluvialis possesses the highest intracellular astaxanthin content and is now believed to be a good producer of astaxanthin, it has intrinsic shortcomings such as slow growth rate, low biomass yield, and a high light requirement. In contrast, C. zofingiensis grows fast phototrophically, heterotrophically and mixtrophically, is easy to be cultured and scaled up both indoors and outdoors, and can achieve ultrahigh cell densities. These robust biotechnological traits provide C. zofingiensis with high potential to be a better organism than H. pluvialis for mass astaxanthin production. This review aims to provide an overview of the biology and industrial potential of C. zofingiensis as an alternative astaxanthin producer. The path forward for further expansion of the astaxanthin production from C. zofingiensis with respect to both challenges and opportunities is also discussed.

  7. Assessment and comparison of in vitro immunoregulatory activity of three astaxanthin stereoisomers

    Science.gov (United States)

    Sun, Weihong; Xing, Lihong; Lin, Hong; Leng, Kailiang; Zhai, Yuxiu; Liu, Xiaofang

    2016-04-01

    In recent years, the immune-modulatory role of all- trans astaxanthin from different pigment sources has been studied. It was reported that all- trans astaxanthin might exist as three stereoisomers, and the composition of all- trans stereoisomers in natural materials differs from that of synthetic products. However, the different biological effects of various all- trans stereoisomers still remain unclear. In the present study, we evaluated the bioactivity of three astaxanthin stereoisomers, ( 3S, 3'S)- trans-, ( 3R,3'R)- trans-and meso-trans-astaxanthin, in regulating cell-mediated immune response using mice lymphocytes and peritoneal exudates cells (PECs) systems. After the treatment with three astaxanthin stereoisomers (20 μmol L-1), the lymphocyte proliferation capacity, neutral red phagocytosis of PECs and natural killer (NK) cell cytotoxic activity were comparatively assessed. The results showed that all three astaxanthin stereoisomers significantly promoted lymphocyte proliferation, phagocytic capacity of PECs, and cytotoxic activity of NK cells. Moreover, the ( 3S,3'S)-trans-astaxanthin exhibited a much higher response than others.

  8. EXTRACTION OF ASTAXANTHIN ESTERS FROM SHRIMP WASTE BY CHEMICAL AND MICROBIAL METHODS

    Directory of Open Access Journals (Sweden)

    A. Khanafari, A. Saberi, M. Azar, Gh. Vosooghi, Sh. Jamili, B. Sabbaghzadeh

    2007-04-01

    Full Text Available The carotenoid pigments specifically astaxanthin has many significant applications in food, pharmaceutical and cosmetic industries. The goal of this research was the extraction of Astaxanthin from a certain Persian Gulf shrimp species waste (Penaeus semisulcatus, purification and identification of the pigment by chemical and microbial methods. Microbial fermentation was obtained by inoculation of two Lactobacillus species Lb. plantarum and Lb. acidophilus in the medium culture containing shrimp waste powder by the intervention of lactose sugar, yeast extract, the composition of Both and the coolage (-20oC. The carotenoids were extracted by an organic solvent system. After purification of astaxanthin with the thin layer chromatography method by spectrophotometer, NMR and IR analysis the presence of astaxanthin esters was recognized in this specific species of Persian Gulf shrimp. Results obtained from this study showed that the coolage at –20 oC not only does not have an amplifying effect on the production of astaxanthin but also slightly reduces this effect. Also the effect of intervention of lactose sugar showed more effectiveness in producing astaxanthin than yeast extract or more than with the presence of both. The results also indicated that there is not much difference in the ability of producing the pigment by comparing both Lb. plantarum and Lb. acidophillus. Also results showed the microbial method of extraction of astaxanthin is more effective than chemical method. The pigment extracted from certain amount of shrimp powder, 23.128 mg/g, was calculated.

  9. Subchronic (13-week) toxicity and prenatal developmental toxicity studies of dietary astaxanthin in rats.

    Science.gov (United States)

    Vega, Katherine; Edwards, James; Beilstein, Paul

    2015-12-01

    Two studies examined the effects of dietary astaxanthin on Hanlbm Wistar (SPF) rats. Male and female rats receiving astaxanthin concentrations up to 1.52% of the feed for 13 weeks showed no evidence of toxicity; no effects were noted in the offspring of female rats exposed to astaxanthin at up to 1.39% of the feed during the period of organogenesis (GD 7-16). Discoloration of the feces and yellow pigmentation of adipose tissue was seen in the 13-week study, an intrinsic property of the substance, and not a sign of toxicity. Differences between the control and astaxanthin groups, some of which reached statistical significance, were generally sporadic (i.e., transient and/or not related to astaxanthin concentration) and not considered of biological or toxicological significance. Blood cholesterol levels, for example, were greater in animals receiving astaxanthin for 13 weeks, but remained within the normal range. The highest dietary concentration of astaxanthin in each of the studies is proposed as a no-observable-adverse-effect level (NOAEL). Specifically, 1.52% for the 13-week study, corresponding to a mean intake of 1033 mg/kg bw/day (range: 880-1240 mg/kg bw/day), and 1.39% for the developmental toxicity study, corresponding to a mean intake of approximately 830 mg/kg bw/day (range: 457-957 mg/kg bw/day). PMID:26493001

  10. Inhibition of inflammation by astaxanthin alleviates cognition deficits in diabetic mice.

    Science.gov (United States)

    Zhou, Xiaoyan; Zhang, Fang; Hu, Xiaotong; Chen, Jing; Wen, Xiangru; Sun, Ying; Liu, Yonghai; Tang, Renxian; Zheng, Kuiyang; Song, Yuanjian

    2015-11-01

    Neurons in the hippocampal and cortical functional regions are more susceptible to damage induced by hyperglycemia, which can result in severe spatial learning and memory impairment. Neuroprotection ameliorates cognitive impairment induced by hyperglycemia in diabetic encephalopathy (DE). Astaxanthin has been widely studied in diabetes mellitus and diabetic complications due to its hypoglycemic, antioxidant and anti-apoptotic effects. However, whether astaxanthin can alleviate cognition deficits induced by DE and its precise mechanisms remain undetermined. In this study, DE was induced by streptozotocin (STZ, 150 mg/kg) in ICR mice. We observed the effect of astaxanthin on cognition and investigated its potential mechanisms in DE mice. Results showed that astaxanthin treatment significantly decreased the latency and enhanced the distance and time spent in the target quadrant in the Morris water maze test. Furthermore, neuronal survival was significantly increased in the hippocampal CA3 region and the frontal cortex following treatment with astaxanthin. Meanwhile, immunoblotting was used to observe the nuclear translocation of nuclear factor-kappaB (NF-κB) p65 and the expression of tumor necrosis factor-α (TNF-α) in the hippocampus and frontal cortex. The results indicated that astaxanthin could inhibit NF-κB nuclear translocation and downregulate TNF-α expression in the hippocampus and frontal cortex. Overall, the present study implied that astaxanthin could improve cognition by protecting neurons against inflammation injury potentially through inhibiting the nuclear translocation of NF-κB and down-regulating TNF-α. PMID:26272354

  11. Studies on the metabolism of astaxanthin in the rainbow trout (Salmo gairdneri)

    Energy Technology Data Exchange (ETDEWEB)

    Al-Khalifah, A.S.

    1986-01-01

    Racemic astaxanthin was fed to rainbow trout (Salmo gairdneri) for 2, 4, and 6 weeks. The fish showed a bright pink coloration of the skin and flesh; the highest amount of astaxanthin was found in the skin of fish fed the test diet for six weeks. Lutein, 3-epilutein, and zeaxanthin were also detected in the flesh and skin; it was concluded that astaxanthin was converted to zeaxanthin in the skin. The mean vitamin A content of the liver was determined; the ratio of vitamin A/sub 1/:vitamin A/sub 2/ was approximately 1:3. Retinol and 3,4-dehydroretinol were extracted from the intestine of rainbow trout low in vitamin A, after force feeding with astaxanthin using a feeding tube. Antibiotic-treated fish had no marked difference in vitamin A content compared with a control group that received no antibiotic. This proves that astaxanthin was converted to vitamin A in fish depleted of vitamin A, that microorganisms were not involved in the conversion, and that conversion occurred in the intestine. An in vitro study using /sup 3/H 3S, 3S'-astaxanthin incubated with duodenal and ileal segments of the intestine provided HLPC and radioisotope data, which showed that rainbow trout were able to bioconvert astaxanthin to vitamin A.

  12. Studies on the metabolism of astaxanthin in the rainbow trout (Salmo gairdneri)

    International Nuclear Information System (INIS)

    Racemic astaxanthin was fed to rainbow trout (Salmo gairdneri) for 2, 4, and 6 weeks. The fish showed a bright pink coloration of the skin and flesh; the highest amount of astaxanthin was found in the skin of fish fed the test diet for six weeks. Lutein, 3-epilutein, and zeaxanthin were also detected in the flesh and skin; it was concluded that astaxanthin was converted to zeaxanthin in the skin. The mean vitamin A content of the liver was determined; the ratio of vitamin A1:vitamin A2 was approximately 1:3. Retinol and 3,4-dehydroretinol were extracted from the intestine of rainbow trout low in vitamin A, after force feeding with astaxanthin using a feeding tube. Antibiotic-treated fish had no marked difference in vitamin A content compared with a control group that received no antibiotic. This proves that astaxanthin was converted to vitamin A in fish depleted of vitamin A, that microorganisms were not involved in the conversion, and that conversion occurred in the intestine. An in vitro study using 3H 3S, 3S'-astaxanthin incubated with duodenal and ileal segments of the intestine provided HLPC and radioisotope data, which showed that rainbow trout were able to bioconvert astaxanthin to vitamin A

  13. Astaxanthin ameliorates aluminum chloride-induced spatial memory impairment and neuronal oxidative stress in mice.

    Science.gov (United States)

    Al-Amin, Md Mamun; Reza, Hasan Mahmud; Saadi, Hasan Mahmud; Mahmud, Waich; Ibrahim, Abdirahman Adam; Alam, Musrura Mefta; Kabir, Nadia; Saifullah, A R M; Tropa, Sarjana Tarannum; Quddus, A H M Ruhul

    2016-04-15

    Aluminum chloride induces neurodegenerative disease in animal model. Evidence suggests that aluminum intake results in the activation of glial cells and generation of reactive oxygen species. By contrast, astaxanthin is an antioxidant having potential neuroprotective activity. In this study, we investigate the effect of astaxanthin on aluminum chloride-exposed behavioral brain function and neuronal oxidative stress (OS). Male Swiss albino mice (4 months old) were divided into 4 groups: (i) control (distilled water), (ii) aluminum chloride, (iii) astaxanthin+aluminum chloride, and (iv) astaxanthin. Two behavioral tests; radial arm maze and open field test were conducted, and OS markers were assayed from the brain and liver tissues following 42 days of treatment. Aluminum exposed group showed a significant reduction in spatial memory performance and anxiety-like behavior. Moreover, aluminum group exhibited a marked deterioration of oxidative markers; lipid peroxidation (MDA), nitric oxide (NO), glutathione (GSH) and advanced oxidation of protein products (AOPP) in the brain. To the contrary, co-administration of astaxanthin and aluminum has shown improved spatial memory, locomotor activity, and OS. These results indicate that astaxanthin improves aluminum-induced impaired memory performances presumably by the reduction of OS in the distinct brain regions. We suggest a future study to determine the underlying mechanism of astaxanthin in improving aluminum-exposed behavioral deficits. PMID:26927754

  14. Astaxanthin from Haematococcus pluvialis Prevents Oxidative Stress on Human Endothelial Cells without Toxicity

    Directory of Open Access Journals (Sweden)

    Philippe Régnier

    2015-05-01

    Full Text Available Astaxanthin, a powerful antioxidant, is a good candidate for the prevention of intracellular oxidative stress. The aim of the study was to compare the antioxidant activity of astaxanthin present in two natural extracts from Haematococcus pluvialis, a microalgae strain, with that of synthetic astaxanthin. Natural extracts were obtained either by solvent or supercritical extraction methods. UV, HPLC-DAD and (HPLC-(atmospheric pressure chemical ionization (APCI+/ion trap-MS characterizations of both natural extracts showed similar compositions of carotenoids, but different percentages in free astaxanthin and its ester derivatives. The Trolox equivalent antioxidant capacity (TEAC assay showed that natural extracts containing esters displayed stronger antioxidant activities than free astaxanthin. Their antioxidant capacities to inhibit intracellular oxidative stress were then evaluated on HUVEC cells. The intracellular antioxidant activity in natural extracts was approximately 90-times higher than synthetic astaxanthin (5 µM. No modification, neither in the morphology nor in the viability, of vascular human cells was observed by in vitro biocompatibility study up to 10 µM astaxanthin concentrations. Therefore, these results revealed the therapeutic potential of the natural extracts in vascular human cell protection against oxidative stress without toxicity, which could be exploited in prevention and/or treatment of cardiovascular diseases.

  15. Astaxanthin production in marine pelagic copepods grazing on two different phytoplankton diets

    Science.gov (United States)

    Van Nieuwerburgh, Lies; Wänstrand, Ingrid; Liu, Jianguo; Snoeijs, Pauli

    2005-02-01

    The red carotenoid astaxanthin is a powerful natural antioxidant of great importance in aquatic food webs where it is abundant in eggs and body tissues of fish and crustaceans. Little is known about the impact of the phytoplankton diet on astaxanthin production in copepods, its major pelagic producers. We followed the transfer of carotenoids from phytoplankton to copepods in a mesocosm experiment on the northern Atlantic coast (Norway) and recorded the astaxanthin production in copepods. Wild copepods grazed on nutrient-manipulated phytoplankton blooms, which differed in community composition and nutrient status (nitrogen or silicate limitation). The copepod pigments consisted mainly of free astaxanthin and mono- and diesters of astaxanthin. We found no significant difference in astaxanthin production per copepod individual or per unit C depending on the phytoplankton community. However, in the mesocosms astaxanthin per unit C decreased compared with natural levels, probably through a lower demand for photoprotection by the copepods in the dense phytoplankton blooms. The total astaxanthin production per litre was higher in the silicate-limited mesocosms through increased copepod density. Pigment ratio comparisons suggested that the copepod diet here consisted more of diatoms than in the nitrogen-limited mesocosms. Silicate-saturated diatoms were less grazed, possibly because they could invest more in defence mechanisms against their predators. Our study suggests that the production of astaxanthin in aquatic systems can be affected by changes in nutrient dynamics mediated by phytoplankton community composition and copepod population growth. This bottom-up force may have implications for antioxidant protection at higher trophic levels in the food web.

  16. Effect of astaxanthin on hepatocellular injury following ischemia/reperfusion

    International Nuclear Information System (INIS)

    This study investigated the effect of astaxanthin (ASX; 3,3-dihydroxybeta, beta-carotene-4,4-dione), a water-dispersible synthetic carotenoid, on liver ischemia-reperfusion (IR) injury. Astaxanthin (5 mg/kg/day) or olive oil was administered to rats via intragastric intubation for 14 consecutive days before the induction of hepatic IR. On the 15th day, blood vessels supplying the median and left lateral hepatic lobes were occluded with an arterial clamp for 60 min, followed by 60 min reperfusion. At the end of the experimental period, blood samples were obtained from the right ventricule to determine plasma alanine aminotransferase (ALT) and xanthine oxidase (XO) activities and animals were sacrificed to obtain samples of nonischemic and postischemic liver tissue. The effects of ASX on IR injury were evaluated by assessing hepatic ultrastructure via transmission electron microscopy and by histopathological scoring. Hepatic conversion of xanthine dehygrogenase (XDH) to XO, total GSH and protein carbonyl levels were also measured as markers of oxidative stress. Expression of NOS2 was determined by immunohistochemistry and Western blot analysis while nitrate/nitrite levels were measured via spectral analysis. Total histopathological scoring of cellular damage was significantly decreased in hepatic IR injury following ASX treatment. Electron microscopy of postischemic tissue demonstrated parenchymal cell damage, swelling of mitochondria, disarrangement of rough endoplasmatic reticulum which was also partially reduced by ASX treatment. Astaxanthine treatment significantly decreased hepatic conversion of XDH to XO and tissue protein carbonyl levels following IR injury. The current results suggest that the mechanisms of action by which ASX reduces IR damage may include antioxidant protection against oxidative injury.

  17. Effects of the Levels of Astaxanthin in the Diet on the Flesh Pigmentation of Rainbow Trout

    OpenAIRE

    ERDEM, Muammer; ERGÜN, Sebahattin

    2000-01-01

    A feeding trial was conducted to study the effects of dietary astaxanthin concentration on muscle pigmentation of rainbow trout ( Oncorhynchus mykiss) with a mean initial weight of 270 g fed diets supplemented with astaxanthin in diet concentrations of 60 (group II) and 90 mg/kg (group III) for 35 days. A control (I) group received a diet without astaxanthin. At the end of the experiment, the trout showed average body weight increases of 250.660g, 261.675 g and 234.410 g, and the flesh rea...

  18. Gastric inflammatory markers and interleukins in patients with functional dyspepsia treated with astaxanthin

    DEFF Research Database (Denmark)

    Andersen, L.P.; Holck, Susanne; Kupcinskas, L.;

    2007-01-01

    The chronic active inflammation caused by Helicobacter pylori is dominated by neutrophils, macrophages, lymphocytes and plasma cells. Several interleukins are involved in the inflammatory process. The aim of this study was to investigate the effect of astaxanthin on gastric inflammation in patien...... humans, and may be due to the minor effect when the host have access to antioxidants in their diet.......-regulation of CD8 in patients with H. pylori treated with astaxanthin. Astaxanthin had an effect on the inflammation and on the density of H. pylori in mice in a study where the diet could be standardized without antioxidants (Bennedsen et al., 1999). These dietary conditions are impossible in studies involving...

  19. Preparation and Characterization of Astaxanthin Nanoparticles by Solvent-Diffusion Technique

    International Nuclear Information System (INIS)

    In this work, astaxanthin nanoparticles were prepared in aqueous media using solvent-diffusion technique. Sodium caseinate, gelatin, Polysorbate 20 and gum Arabic were selected as different food grade surface active molecules for the stabilization of the produced nanoparticles. Results showed that among produced astaxanthin nanoparticles, the Polysorbate 20-stabilized nanoparticles showed the smallest particle size; gum Arabic-stabilized nanoparticles had the smallest polydispersity index and highest physical stability in simulated gastric fluid (SGF); and those stabilized using gelatin had the highest zeta potential. Sodium caseinate stabilized nanoparticles had the highest astaxanthin content in fresh samples as compared to other prepared nano dispersions. (author)

  20. Characterization of Flavan-3-ols and Expression of MYB and Late Pathway Genes Involved in Proanthocyanidin Biosynthesis in Foliage of Vitis bellula

    Directory of Open Access Journals (Sweden)

    Ke-Gang Li

    2013-03-01

    Full Text Available Proanthocyanidins (PAs are fundamental nutritional metabolites in different types of grape products consumed by human beings. Although the biosynthesis of PAs in berry of Vitis vinifera has gained intensive investigations, the understanding of PAs in other Vitis species is limited. In this study, we report PA formation and characterization of gene expression involved in PA biosynthesis in leaves of V. bellula, a wild edible grape species native to south and south-west China. Leaves are collected at five developmental stages defined by sizes ranging from 0.5 to 5 cm in length. Analyses of thin layer chromatography (TLC and high performance liquid chromatography-photodiode array detector (HPLC-PAD show the formation of (+-catechin, (−-epicatechin, (+-gallocatechin and (−-epigallocatechin during the entire development of leaves. Analyses of butanol-HCl boiling cleavage coupled with spectrometry measurement at 550 nm show a temporal trend of extractable PA levels, which is characterized by an increase from 0.5 cm to 1.5 cm long leaves followed by a decrease in late stages. TLC and HPLC-PAD analyses identify cyanidin, delphinidin and pelargonidin produced from the cleavage of PAs in the butanol-HCl boiling, showing that the foliage PAs of V. bellula include three different types of extension units. Four cDNAs, which encode VbANR, VbDFR, VbLAR1 and VbLAR2, respectively, are cloned from young leaves. The expression patterns of VbANR and VbLAR2 but not VbLAR1 and VbDFR follow a similar trend as the accumulation patterns of PAs. Two cDNAs encoding VbMYBPA1 and VbMYB5a, the homologs of which have been demonstrated to regulate the expression of both ANR and LAR in V. vinifera, are also cloned and their expression profiles are similar to those of VbANR and VbLAR2. In contrast, the expression profiles of MYBA1 and 2 homologs involved in anthocyanin biosynthesis are different from those of VbANR and VbLAR2. Our data show that both ANR and LAR branches are

  1. The Ternary Complex of PrnB (the Second Enzyme in the Pyrrolnitrin Biosynthesis Pathway), Tryptophan, and Cyanide Yields New Mechanistic Insights into the Indolamine Dioxygenase Superfamily*

    OpenAIRE

    Zhu, Xiaofeng; van Pée, Karl-Heinz; Naismith, James H.

    2010-01-01

    Pyrrolnitrin (3-chloro-4-(2′-nitro-3′-chlorophenyl)pyrrole) is a broad-spectrum antifungal compound isolated from Pseudomonas pyrrocinia. Four enzymes (PrnA, PrnB, PrnC, and PrnD) are required for pyrrolnitrin biosynthesis from tryptophan. PrnB rearranges the indole ring of 7-Cl-l-tryptophan and eliminates the carboxylate group. PrnB shows robust activity in vivo, but in vitro activity for PrnB under defined conditions remains undetected. The structure of PrnB establishes that the enzyme belo...

  2. Analysis of iridoids content and expression studies of genes encoding early enzymes in the indol terpenoid biosynthesis pathway in Catharanthus roseus

    OpenAIRE

    Natalia Palacios-Rojas; Mark Leech

    2007-01-01

    Terpenoid indole alkaloids (TIA) are of pharmaceutical importance, however the industrial use of these compouds is very limited because its accumulation is very low in plant tissues. TIA are derived f rom the shikimate and terpenoid pathways, which supply secologanin and tryptamine, the indole and iridoid moieties, respectively. Secololganin is a terpenoid which is belived to be synthesised the MEP pathway rather than by the acetate/mevalonic acid pathway. Secologanin is thought to be a limit...

  3. Review of genotoxicity and rat carcinogenicity investigations with astaxanthin.

    Science.gov (United States)

    Edwards, James A; Bellion, Phillip; Beilstein, Paul; Rümbeli, Robert; Schierle, Joseph

    2016-03-01

    Synthetic astaxanthin has been extensively tested for safety. Genotoxicity studies including Ames and in vitro Micronucleus Tests show absence of genotoxic potential. Although a long-term mouse study showed no carcinogenicity potential, the rat carcinogenicity study with dietary dosages of 0 (control), 0 (placebo beadlet), 40, 200 and 1000 mg astaxanthin/kg bw/day showed an increased incidence of benign, hepatocellular adenoma in females only, at 200 mg/kg bw/day and above. There was no clear evidence of toxicity during the in-life phase. Discoloration of feces was observed and a reduction in body weight gain in all groups receiving beadlets, probably reflecting a nutritional influence. Blood sampling confirmed systemic exposure and some minor clinical chemistry differences in females at 200 and 1000 mg/kg bw/day. There was no effect on adjusted liver weight. Histopathological examination showed hepatic changes indicative of slight hepatotoxicity and hepatocyte regeneration in females at 200 and 1000 mg/kg bw/day, in addition to the adenoma. Taking into account this pathological background in the female rat, and a wide variety of other supporting information, it is concluded that the hepatocellular adenoma in female rats was secondary to hepatotoxicity and regeneration, and is most probably a species-specific phenomenon of doubtful human relevance. PMID:26713891

  4. Excited state dynamics of the astaxanthin radical cation

    Science.gov (United States)

    Amarie, Sergiu; Förster, Ute; Gildenhoff, Nina; Dreuw, Andreas; Wachtveitl, Josef

    2010-07-01

    Femtosecond transient absorption spectroscopy in the visible and NIR and ultrafast fluorescence spectroscopy were used to examine the excited state dynamics of astaxanthin and its radical cation. For neutral astaxanthin, two kinetic components corresponding to time constants of 130 fs (decay of the S 2 excited state) and 5.2 ps (nonradiative decay of the S 1 excited state) were sufficient to describe the data. The dynamics of the radical cation proved to be more complex. The main absorption band was shifted to 880 nm (D 0 → D 3 transition), showing a weak additional band at 1320 nm (D 0 → D 1 transition). We found, that D 3 decays to the lower-lying D 2 within 100 fs, followed by a decay to D 1 with a time constant of 0.9 ps. The D 1 state itself exhibited a dual behavior, the majority of the population is transferred to the ground state in 4.9 ps, while a small population decays on a longer timescale of 40 ps. Both transitions from D 1 were found to be fluorescent.

  5. The zinc cluster proteins Upc2 and Ecm22 promote filamentation in Saccharomyces cerevisiae by sterol biosynthesis-dependent and -independent pathways.

    Science.gov (United States)

    Woods, Kelly; Höfken, Thomas

    2016-02-01

    The transition between a unicellular yeast form to multicellular filaments is crucial for budding yeast foraging and the pathogenesis of many fungal pathogens such as Candida albicans. Here, we examine the role of the related transcription factors Ecm22 and Upc2 in Saccharomyces cerevisiae filamentation. Overexpression of either ECM22 or UPC2 leads to increased filamentation, whereas cells lacking both ECM22 and UPC2 do not exhibit filamentous growth. Ecm22 and Upc2 positively control the expression of FHN1, NPR1, PRR2 and sterol biosynthesis genes. These genes all play a positive role in filamentous growth, and their expression is upregulated during filamentation in an Ecm22/Upc2-dependent manner. Furthermore, ergosterol content increases during filamentous growth. UPC2 expression also increases during filamentation and is inhibited by the transcription factors Sut1 and Sut2. The expression of SUT1 and SUT2 in turn is under negative control of the transcription factor Ste12. We suggest that during filamentation Ste12 becomes activated and reduces SUT1/SUT2 expression levels. This would result in increased UPC2 levels and as a consequence to transcriptional activation of FHN1, NPR1, PRR2 and sterol biosynthesis genes. Higher ergosterol levels in combination with the proteins Fhn1, Npr1 and Prr2 would then mediate the transition to filamentous growth. PMID:26448198

  6. Tissue distribution of 14C-astaxanthin in the Atlantic salmon (Salmo salar)

    International Nuclear Information System (INIS)

    Atlantic salmon (Salmo salar) were fed a diet containing 14C-labelled astaxanthin for five subsequent days. Ten days after the last feeding, two fish were sampled and submitted to whole-body autoradiography. A high degree of radioactivity was present in the dorsal cutis, the bile, the intestinal mucosa, the caudal kidney and the developing eggs. An intermediate degree of radiolabelling was found in the muscle and the cranial kidney, while only traces of radioactivity were recorded in the blood, the spleen and the gills. Contrary to the prevailing concensus, the level of astaxanthin and/or metabolites was higher in the myocommata than in the myotome. Furthermore, the substantial radiolabelling in the dorsal cutis strongly suggests that astaxanthin and/or its metabolites show affinity for melanin. Finally, the results give evidence for urinary and biliary excretion of astaxanthin-derived metabolites and for the likelihood of enterohepatic circulation

  7. Sequential Heterotrophy-Dilution-Photoinduction Cultivation of Haematococcus pluvialis for efficient production of astaxanthin.

    Science.gov (United States)

    Wan, Minxi; Zhang, Zhen; Wang, Jun; Huang, Jianke; Fan, Jianhua; Yu, Anquan; Wang, Weiliang; Li, Yuanguang

    2015-12-01

    A novel cultivation strategy called "Sequential Heterotrophy-Dilution-Photoinduction" was successfully applied in the cultivation of Haematococcus pluvialis to produce astaxanthin effectively. Cells were first cultivated heterotrophically to achieve a high cell density, then were diluted to a suitable concentration and switched to a favorable environment for cells acclimation. Finally, the culture was transferred to high light environment for astaxanthin accumulation. By this strategy, the dry cell weight of 26 g/L and biomass productivity of 64.1mg/L/h were obtained in heterotrophy stage which surpassed ever before reported in literatures. Meanwhile, the cells could accumulate considerable astaxanthin up to 4.6% of dry cell weight after 10 days of photoinduction. Furthermore, the application prospects of the strategy were confirmed further by outdoor experiments. Therefore, this novel strategy provided a promising approach for high-efficient production of natural astaxanthin from H. pluvialis to meet the huge demand of this high value product. PMID:26433152

  8. Hyperspectral imaging based on diffused laser light for prediction of astaxanthin coating concentration

    DEFF Research Database (Denmark)

    Ljungqvist, Martin Georg; Nielsen, Otto Højager Attermann; Frosch, Stina;

    2014-01-01

    We present a study on predicting the concentration level of synthetic astaxanthin in fish feed pellet coating using multi- and hyperspectral image analysis. This was done in parallel using two different vision systems. A new instrument for hyperspectral imaging, the SuperK setup, using a super...... the astaxanthin concentration from the spectral image data, the synthetic astaxanthin content in the pellets was measured with the established standard technique; high-pressure liquid chromatography (HPLC). Regression analysis was done using partial least squares regression (PLSR) and the sparse regression method...... concentration. The results show that it is possible to predict the synthetic astaxanthin concentration in the coating well enough for quality control using both multi- and hyperspectral image analysis, while the SuperK setup performs with higher accuracy than the VideometerLab device for this particular problem...

  9. Increase in the astaxanthin synthase gene (crtS) dose by in vivo DNA fragment assembly in Xanthophyllomyces dendrorhous

    OpenAIRE

    Contreras, Gabriela; Barahona, Salvador; Rojas, María Cecilia; Baeza, Marcelo; Cifuentes, Víctor; Alcaíno, Jennifer

    2013-01-01

    Background Xanthophyllomyces dendrorhous is a basidiomycetous yeast that is relevant to biotechnology, as it can synthesize the carotenoid astaxanthin. However, the astaxanthin levels produced by wild-type strains are low. Although different approaches for promoting increased astaxanthin production have been attempted, no commercially competitive results have been obtained thus far. A promising alternative to facilitate the production of carotenoids in this yeast involves the use of genetic m...

  10. Astaxanthin prevents and reverses diet-induced insulin resistance and steatohepatitis in mice: A comparison with vitamin E

    OpenAIRE

    Yinhua Ni; Mayumi Nagashimada; Fen Zhuge; Lili Zhan; Naoto Nagata; Akemi Tsutsui; Yasuni Nakanuma; Shuichi Kaneko; Tsuguhito Ota

    2015-01-01

    Hepatic insulin resistance and nonalcoholic steatohepatitis (NASH) could be caused by excessive hepatic lipid accumulation and peroxidation. Vitamin E has become a standard treatment for NASH. However, astaxanthin, an antioxidant carotenoid, inhibits lipid peroxidation more potently than vitamin E. Here, we compared the effects of astaxanthin and vitamin E in NASH. We first demonstrated that astaxanthin ameliorated hepatic steatosis in both genetically (ob/ob) and high-fat-diet-induced obese ...

  11. Effect of Diets Supplemented with Different Sources of Astaxanthin on the Gonad of the Sea Urchin Anthocidaris crassispina

    OpenAIRE

    Jiang-Hai Wang; Jian-Ping Yuan; Juan Peng

    2012-01-01

    The effect of the microalgae Haematococcus pluvialis and Chorella zofingiensis, and synthetic astaxanthin on the gonad of the sea urchin Anthocidaris crassispina was studied. The basal diet was supplemented with H. pluvialis, C. zofingiensis, or synthetic astaxanthin, at two levels of astaxanthin (approximately 400 mg/kg and 100 mg/kg), to obtain t...

  12. Response Surface Methodology for Ultrasound-Assisted Extraction of Astaxanthin from Haematococcus pluvialis

    OpenAIRE

    Hong-Fu Wu; Chang-Xiu Wang; Hua-Wen Li; Tang-Bin Zou; Qing Jia

    2013-01-01

    Astaxanthin is a novel carotenoid nutraceutical occurring in many crustaceans and red yeasts. It has exhibited various biological activities including prevention or amelioration of cardiovascular disease, gastric ulcer, hypertension, and diabetic nephropathy. In this study, ultrasound-assisted extraction was developed for the effective extraction of astaxanthin from Haematococcus pluvialis. Some parameters such as extraction solvent, liquid-to-solid ratio, extraction temperature, and extracti...

  13. Four Different Methods Comparison for Extraction of Astaxanthin from Green Alga Haematococcus pluvialis

    OpenAIRE

    Shengzhao Dong; Yi Huang; Rui Zhang; Shihui Wang; Yun Liu

    2014-01-01

    Haematococcus pluvialis is one of the potent organisms for production of astaxanthin. Up to now, no efficient method has been achieved due to its thick cell wall hindering solvent extraction of astaxanthin. In this study, four different methods, hydrochloric acid pretreatment followed by acetone extraction (HCl-ACE), hexane/isopropanol (6 : 4, v/v) mixture solvents extraction (HEX-IPA), methanol extraction followed by acetone extraction (MET-ACE, 2-step extraction), and soy-oil extraction, we...

  14. EXTRACTION OF ASTAXANTHIN ESTERS FROM SHRIMP WASTE BY CHEMICAL AND MICROBIAL METHODS

    OpenAIRE

    A. Khanafari, A. Saberi, M. Azar, Gh. Vosooghi, Sh. Jamili, B. Sabbaghzadeh

    2007-01-01

    The carotenoid pigments specifically astaxanthin has many significant applications in food, pharmaceutical and cosmetic industries. The goal of this research was the extraction of Astaxanthin from a certain Persian Gulf shrimp species waste (Penaeus semisulcatus), purification and identification of the pigment by chemical and microbial methods. Microbial fermentation was obtained by inoculation of two Lactobacillus species Lb. plantarum and Lb. acidophilus in the medium culture containing shr...

  15. The effects of astaxanthin in improving age associated declines of Th2 immune responses

    OpenAIRE

    Motoko Morimoto

    2013-01-01

    [Objective] Astaxanthin is one of the natural antioxidant carotenoid mainly derived from crab,salmon and trout. This study aims to determine whether dietary astaxanthincould modulate mucosal immunity in the gut in aged mice. [Method] Aged (18 months old) Balb/c female mice were orally administered with 6mg/kg body weight of astaxanthin or saline for 4 weeks. After 3 weeks, micewere infected with Nippostrongylus brasiliensis(Nb), which is gastroinfectional nematode in rodents. Tissues were ...

  16. Astaxanthin prevents changes in the activities of thioredoxin reductase and paraoxonase in hypercholesterolemic rabbits

    OpenAIRE

    Paula R. Augusti; Quatrin, Andréia; Somacal, Sabrina; Conterato, Greicy MM; Sobieski, Rocheli; Ruviaro, Amanda R; Maurer, Luana H; Duarte, Marta MF; Roehrs, Miguel; Emanuelli, Tatiana

    2012-01-01

    This study explored the effects of the antioxidant astaxanthin on paraoxonase and thioredoxin reductase activities as well as on other oxidative stress parameters and on the lipid profile in hypercholesterolemic rabbits. Rabbits were fed a standard or a hypercholesterolemic diet alone or supplemented with 50, 100 and 500 mg/100 g of astaxanthin for 60 days. Antioxidant enzymes activities, lipid profile and oxidative stress markers were evaluated in the serum. The hypercholesterolemic diet inc...

  17. Anti-inflammatory Effect of Astaxanthin on the Sickness Behavior Induced by Diabetes Mellitus.

    Science.gov (United States)

    Ying, Chang-jiang; Zhang, Fang; Zhou, Xiao-yan; Hu, Xiao-tong; Chen, Jing; Wen, Xiang-ru; Sun, Ying; Zheng, Kui-yang; Tang, Ren-xian; Song, Yuan-jian

    2015-10-01

    Chronic inflammation appears to play a critical role in sickness behavior caused by diabetes mellitus. Astaxanthin has been used in treating diabetes mellitus and diabetic complications because of its neuroprotective and anti-inflammatory actions. However, whether astaxanthin can improve sickness behavior induced by diabetes and its potential mechanisms are still unknown. The aim of this study was to investigate the effects of astaxanthin on diabetes-elicited abnormal behavior in mice and its corresponding mechanisms. An experimental diabetic model was induced by streptozotocin (150 mg/kg) and astaxanthin (25 mg/kg/day) was provided orally for 10 weeks. Body weight and water consumption were measured, and the sickness behavior was evaluated by the open field test (OFT) and closed field test (CFT). The expression of glial fibrillary acidic protein (GFAP) was measured, and the frontal cortical cleaved caspase-3 positive cells, interleukin-6 (IL-6), and interleukin-1β (IL-1β) expression levels were also investigated. Furthermore, cystathionine β-synthase (CBS) in the frontal cortex was detected to determine whether the protective effect of astaxanthin on sickness behavior in diabetic mice is closely related to CBS. As expected, we observed that astaxanthin improved general symptoms and significantly increase horizontal distance and the number of crossings in the OFT and CFT. Furthermore, data showed that astaxanthin could decrease GFAP-positive cells in the brain and down-regulate the cleaved caspase-3, IL-6, and IL-1β, and up-regulate CBS in the frontal cortex. These results suggest that astaxanthin provides neuroprotection against diabetes-induced sickness behavior through inhibiting inflammation, and the protective effects may involve CBS expression in the brain. PMID:25971983

  18. Astaxanthin decreased oxidative stress and inflammation and enhanced immune response in humans

    OpenAIRE

    Line Larry L; Kim Yoo; Chyun Jong; Park Jean; Chew Boon P

    2010-01-01

    Abstract Background Astaxanthin modulates immune response, inhibits cancer cell growth, reduces bacterial load and gastric inflammation, and protects against UVA-induced oxidative stress in in vitro and rodent models. Similar clinical studies in humans are unavailable. Our objective is to study the action of dietary astaxanthin in modulating immune response, oxidative status and inflammation in young healthy adult female human subjects. Methods Participants (averaged 21.5 yr) received 0, 2, o...

  19. Near-Infrared Hyper-spectral Image Analysis of Astaxanthin Concentration in Fish Feed Coating

    DEFF Research Database (Denmark)

    Ljungqvist, Martin Georg; Ersbøll, Bjarne Kjær; Kobayashi, K.;

    2012-01-01

    The aim of this study was to investigate the possibility of predicting concentration levels of synthetic astaxanthin coating of aquaculture feed pellets by hyper-spectral image analysis in the near infra-red (NIR) range and optical filter design. The imaging devices used were a Videometer...... for prediction of the concentration level. The results show that it is possible to predict the level of synthetic astaxanthin coating using either hyper-spectral imaging or three bandpass filters (BPF)....

  20. Astaxanthin: Sources, Extraction, Stability, Biological Activities and Its Commercial Applications—A Review

    OpenAIRE

    Ranga Rao Ambati; Siew-Moi Phang; Sarada Ravi; Ravishankar Gokare Aswathanarayana

    2014-01-01

    There is currently much interest in biological active compounds derived from natural resources, especially compounds that can efficiently act on molecular targets, which are involved in various diseases. Astaxanthin (3,3′-dihydroxy-β, β′-carotene-4,4′-dione) is a xanthophyll carotenoid, contained in Haematococcus pluvialis, Chlorella zofingiensis, Chlorococcum, and Phaffia rhodozyma. It accumulates up to 3.8% on the dry weight basis in H. pluvialis. Our recent published data on astaxanthin ex...

  1. Astaxanthin prevents and reverses diet-induced insulin resistance and steatohepatitis in mice: A comparison with vitamin E.

    Science.gov (United States)

    Ni, Yinhua; Nagashimada, Mayumi; Zhuge, Fen; Zhan, Lili; Nagata, Naoto; Tsutsui, Akemi; Nakanuma, Yasuni; Kaneko, Shuichi; Ota, Tsuguhito

    2015-01-01

    Hepatic insulin resistance and nonalcoholic steatohepatitis (NASH) could be caused by excessive hepatic lipid accumulation and peroxidation. Vitamin E has become a standard treatment for NASH. However, astaxanthin, an antioxidant carotenoid, inhibits lipid peroxidation more potently than vitamin E. Here, we compared the effects of astaxanthin and vitamin E in NASH. We first demonstrated that astaxanthin ameliorated hepatic steatosis in both genetically (ob/ob) and high-fat-diet-induced obese mice. In a lipotoxic model of NASH: mice fed a high-cholesterol and high-fat diet, astaxanthin alleviated excessive hepatic lipid accumulation and peroxidation, increased the proportion of M1-type macrophages/Kupffer cells, and activated stellate cells to improve hepatic inflammation and fibrosis. Moreover, astaxanthin caused an M2-dominant shift in macrophages/Kupffer cells and a subsequent reduction in CD4(+) and CD8(+) T cell recruitment in the liver, which contributed to improved insulin resistance and hepatic inflammation. Importantly, astaxanthin reversed insulin resistance, as well as hepatic inflammation and fibrosis, in pre-existing NASH. Overall, astaxanthin was more effective at both preventing and treating NASH compared with vitamin E in mice. Furthermore, astaxanthin improved hepatic steatosis and tended to ameliorate the progression of NASH in biopsy-proven human subjects. These results suggest that astaxanthin might be a novel and promising treatment for NASH. PMID:26603489

  2. Studies on optimization of nitrogen sources for astaxanthin production by Phaffia rhodozyma

    Institute of Scientific and Technical Information of China (English)

    NI Hui; CHEN Qi-he; RUAN Hui; YANG Yuan-fan; LI Li-jun; WU Guang-bin; HU Yang; HE Guo-qing

    2007-01-01

    Fermentation of Phaffia rhodozyma is a major method for producing astaxanthin, an important pigment with industrial and pharmaceutical application. To improve astaxanthin productivity, single factor and mixture design experiments were used to investigate the effects of nitrogen source on Phaffia rhodozyma cultivation and astaxanthin production. Results of single factor experiments showed nitrogen source could significantly affect P. rhodozyma cultivation with respect to carbon source utilization,yeast growth and astaxanthin accumulation. Further studies of mixture design experiments using (NH4)2SO4, KNO3 and beef extract as nitrogen sources indicated that the proportion of three nitrogen sources was very important to astaxanthin production.Validation experiments showed that the optimal nitrogen source was composed of 0.28 g/L (NH4)2SO4, 0.49 g/L KNO3 and 1.19g/L beef extract. The kinetic characteristics of batch cultivation were investigated in a 5-L pH-stat fermentor. The maximum amount of biomass and highest astaxanthin yield in terms of volume and in terms of biomass were 7.71 mg/L and 1.00 mg/g,respectively.

  3. Effects of Selected Polysorbate and Sucrose Ester Emulsifiers on the Physicochemical Properties of Astaxanthin Nanodispersions

    Directory of Open Access Journals (Sweden)

    Navideh Anarjan

    2013-01-01

    Full Text Available The effects of selected nonionic emulsifiers on the physicochemical characteristics of astaxanthin nanodispersions produced by an emulsification/evaporation technique were studied. The emulsifiers used were polysorbates (Polysorbate 20, Polysorbate 40, Polysorbate 60 and Polysorbate 80 and sucrose esters of fatty acids (sucrose laurate, palmitate, stearate and oleate. The mean particle diameters of the nanodispersions ranged from 70 nm to 150 nm, depending on the emulsifier used. In the prepared nanodispersions, the astaxanthin particle diameter decreased with increasing emulsifier hydrophilicity and decreasing carbon number of the fatty acid in the emulsifier structure. Astaxanthin nanodispersions with the smallest particle diameters were produced with Polysorbate 20 and sucrose laurate among the polysorbates and the sucrose esters, respectively. We also found that the Polysorbate 80- and sucrose oleate-stabilized nanodispersions had the highest astaxanthin losses (i.e., the lowest astaxanthin contents in the final products among the nanodispersions. This work demonstrated the importance of emulsifier type in determining the physicochemical characteristics of astaxanthin nano-dispersions.

  4. Sulforaphane, a cancer chemopreventive agent, induces pathways associated with membrane biosynthesis in response to tissue damage by aflatoxin B{sub 1}

    Energy Technology Data Exchange (ETDEWEB)

    Techapiesancharoenkij, Nirachara [Laboratory of Environmental Toxicology, Chulabhorn Research Institute, Bangkok 10210 (Thailand); Fiala, Jeannette L.A. [Department of Biological Engineering and Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Navasumrit, Panida [Laboratory of Environmental Toxicology, Chulabhorn Research Institute, Bangkok 10210 (Thailand); Croy, Robert G.; Wogan, Gerald N. [Department of Biological Engineering and Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Groopman, John D. [Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205 (United States); Ruchirawat, Mathuros [Laboratory of Environmental Toxicology, Chulabhorn Research Institute, Bangkok 10210 (Thailand); Essigmann, John M., E-mail: jessig@mit.edu [Department of Biological Engineering and Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)

    2015-01-01

    Aflatoxin B{sub 1} (AFB{sub 1}) is one of the major risk factors for liver cancer globally. A recent study showed that sulforaphane (SF), a potent inducer of phase II enzymes that occurs naturally in widely consumed vegetables, effectively induces hepatic glutathione S-transferases (GSTs) and reduces levels of hepatic AFB{sub 1}-DNA adducts in AFB{sub 1}-exposed Sprague Dawley rats. The present study characterized the effects of SF pre-treatment on global gene expression in the livers of similarly treated male rats. Combined treatment with AFB{sub 1} and SF caused reprogramming of a network of genes involved in signal transduction and transcription. Changes in gene regulation were observable 4 h after AFB{sub 1} administration in SF-pretreated animals and may reflect regeneration of cells in the wake of AFB{sub 1}-induced hepatotoxicity. At 24 h after AFB{sub 1} administration, significant induction of genes that play roles in cellular lipid metabolism and acetyl-CoA biosynthesis was detected in SF-pretreated AFB{sub 1}-dosed rats. Induction of this group of genes may indicate a metabolic shift toward glycolysis and fatty acid synthesis to generate and maintain pools of intermediate molecules required for tissue repair, cell growth and compensatory hepatic cell proliferation. Collectively, gene expression data from this study provide insights into molecular mechanisms underlying the protective effects of SF against AFB{sub 1} hepatotoxicity and hepatocarcinogenicity, in addition to the chemopreventive activity of this compound as a GST inducer. - Highlights: • This study revealed sulforaphane (SF)-deregulated gene sets in aflatoxin B{sub 1} (AFB{sub 1})-treated rat livers. • SF redirects biochemical networks toward lipid biosynthesis in AFB{sub 1}-dosed rats. • SF enhanced gene sets that would be expected to favor cell repair and regeneration.

  5. Biosynthesis of monoterpene scent compounds in roses

    OpenAIRE

    Magnard, Jean-Louis; Roccia, Aymeric; Caissard, Jean-Claude; Vergne, Philippe; Sun, Pulu; Hecquet, Romain; Dubois, Annick; Hibrand-Saint Oyant, Laurence; Jullien, Frederic; Nicolè, Florence; Raymond, Olivier; Huguet, Stephanie; Baltenweck-Guyot, Raymonde; Meyer, Sophie; Claudel, Patricia

    2015-01-01

    The scent of roses (Rosa x hybrida) is composed of hundreds of volatile molecules. Monoterpenes represent up to 70% percent of the scent content in some cultivars, such as the Papa Meilland rose. Monoterpene biosynthesis in plants relies on plastid-localized terpene synthases. Combining transcriptomic and genetic approaches, we show that the Nudix hydrolase RhNUDX1, localized in the cytoplasm, is part of a pathway for the biosynthesis of free monoterpene alcohols that contribut...

  6. The de novo and salvage pathways of GDP-mannose biosynthesis are both sufficient for the growth of bloodstream-form Trypanosoma brucei

    OpenAIRE

    Kuettel, Sabine; Wadum, Majken C T; Güther, Maria Lucia S; Mariño, Karina; Riemer, Carolin; Ferguson, Michael A. J.

    2012-01-01

    Summary The sugar nucleotide GDP-mannose is essential for Trypanosoma brucei. Phosphomannose isomerase occupies a key position on the de novo pathway to GDP-mannose from glucose, just before intersection with the salvage pathway from free mannose. We identified the parasite phosphomannose isomerase gene, confirmed that it encodes phosphomannose isomerase activity and localized the endogenous enzyme to the glycosome. We also created a bloodstream-form conditional null mutant of phosphomannose ...

  7. Novel bioassay for the discovery of inhibitors of the 2-C-methyl-D-erythritol 4-phosphate (MEP and terpenoid pathways leading to carotenoid biosynthesis.

    Directory of Open Access Journals (Sweden)

    Natália Corniani

    Full Text Available The 2-C-methyl-D-erythritol 4-phosphate (MEP pathway leads to the synthesis of isopentenyl diphosphate in plastids. It is a major branch point providing precursors for the synthesis of carotenoids, tocopherols, plastoquinone and the phytyl chain of chlorophylls, as well as the hormones abscisic acid and gibberellins. Consequently, disruption of this pathway is harmful to plants. We developed an in vivo bioassay that can measure the carbon flow through the carotenoid pathway. Leaf cuttings are incubated in the presence of a phytoene desaturase inhibitor to induce phytoene accumulation. Any compound reducing the level of phytoene accumulation is likely to interfere with either one of the steps in the MEP pathway or the synthesis of geranylgeranyl diphosphate. This concept was tested with known inhibitors of steps of the MEP pathway. The specificity of this in vivo bioassay was also verified by testing representative herbicides known to target processes outside of the MEP and carotenoid pathways. This assay enables the rapid screen of new inhibitors of enzymes preceding the synthesis of phytoene, though there are some limitations related to the non-specific effect of some inhibitors on this assay.

  8. Scientific Opinion on the safety and efficacy of synthetic astaxanthin as feed additive for salmon and trout, other fish, ornamental fish, crustaceans and ornamental birds

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP

    2014-06-01

    Full Text Available Astaxanthin is a pigmenting carotenoid occurring naturally in plankton, crustaceans and fish. The astaxanthin under assessment is of synthetic origin. The FEEDAP Panel considers synthetic astaxanthin safe for salmonids up to 100 mg/kg complete diet. The conclusion on the safety of astaxanthin for salmonids can be extrapolated to other fish and ornamental fish at the same dose. Dietary concentrations of up to 100 mg astaxanthin/kg feed are safe for crustaceans. The FEEDAP Panel could not conclude on the safety of astaxanthin for ornamental birds. Based on a BMDL10 of 3.4 mg/kg bw per day (calculated for liver hypertrophy in female rat in a carcinogenicity study and applying an uncertainty factor of 100, it is possible to set an ADI of 0.034 mg ATX/kg bw (equivalent to 2.0 mg ATX per 60 kg person per day.  The use of astaxanthin up to the maximum permitted dietary level for salmon and trout is of no concern for the safety of the consumer. As some formulations of astaxanthin may be dusty, and in the absence of data on inhalation toxicity, it is prudent to regard astaxanthin-containing additives as being potentially hazardous by inhalation. In the absence of any information on irritancy to skin or eyes or on skin sensitisation, astaxanthin-containing additives should be regarded as hazardous by exposure to skin or eyes. The FEEDAP Panel considers that the use of synthetic astaxanthin (100 mg astaxanthin/kg fish feed does not pose a significant additional risk to the environment compared with natural astaxanthin. Astaxanthin is efficacious in colouring the flesh of salmonids and the epidermis of crustaceans. Astaxanthin is efficacious in pigmenting the flesh of food-producing fish other than salmonids and the skin of ornamental fish. No conclusion can be made on the efficacy of oral astaxanthin in pigmenting the plumage of ornamental birds.

  9. Astaxanthin, a Carotenoid, Stimulates Immune Responses by Enhancing IFN-γ and IL-2 Secretion in Primary Cultured Lymphocytes in Vitro and ex Vivo

    OpenAIRE

    Kuan-Hung Lin; Kao-Chang Lin; Wan-Jung Lu; Philip-Aloysius Thomas; Thanasekaran Jayakumar; Joen-Rong Sheu

    2015-01-01

    Astaxanthin, a potent antioxidant carotenoid, plays a major role in modulating the immune response. In this study, we examined the immunomodulatory effects of astaxanthin on cytokine production in primary cultured lymphocytes both in vitro and ex vivo. Direct administration of astaxanthin (70–300 nM) did not produce cytotoxicity in lipopolysaccharide (LPS, 100 µg/ mL)- or concanavalin A (Con A, 10 µg/ mL)-activated lymphocytes, whereas astaxanthin alone at 300 nM induced proliferation of sple...

  10. The astaxanthin-induced improvement in lipid metabolism during exercise is mediated by a PGC-1α increase in skeletal muscle

    OpenAIRE

    Liu, Po Hung; Aoi, Wataru; Takami, Maki; Terajima, Hitomi; Tanimura, Yuko; Naito, Yuji; Itoh, Yoshito; Yoshikawa, Toshikazu

    2014-01-01

    Astaxanthin, a xanthophyll carotenoid, accelerates lipid utilization during aerobic exercise, although the underlying mechanism is unclear. The present study investigated the effect of astaxanthin intake on lipid metabolism associated with peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) in mice. Mice were divided into 4 groups: sedentary, sedentary and astaxanthin-treated, exercised, and exercised and astaxanthin-treated. After 2 weeks of treatment, the exercise groups pe...

  11. Fatty acid biosynthesis in actinomycetes

    OpenAIRE

    Gago, Gabriela; Diacovich, Lautaro; Arabolaza, Ana; Tsai, Shiou-Chuan; Gramajo, Hugo

    2011-01-01

    All organisms that produce fatty acids do so via a repeated cycle of reactions. In mammals and other animals, these reactions are catalyzed by a type I fatty acid synthase (FAS), a large multifunctional protein to which the growing chain is covalently attached. In contrast, most bacteria (and plants) contain a type II system in which each reaction is catalyzed by a discrete protein. The pathway of fatty acid biosynthesis in Escherichia coli is well established and has provided a foundation fo...

  12. Taxol biosynthesis and molecular genetics

    OpenAIRE

    Croteau, Rodney; Ketchum, Raymond E.B.; Long, Robert M.; Kaspera, Rüdiger; Wildung, Mark R.

    2006-01-01

    Biosynthesis of the anticancer drug Taxol in Taxus (yew) species involves 19 steps from the universal diterpenoid progenitor geranylgeranyl diphosphate derived by the plastidial methyl erythritol phosphate pathway for isoprenoid precursor supply. Following the committed cyclization to the taxane skeleton, eight cytochrome P450-mediated oxygenations, three CoA-dependent acyl/aroyl transfers, an oxidation at C9, and oxetane (D-ring) formation yield the intermediate baccatin III, to which the fu...

  13. Commercial astaxanthin production derived by green alga Haematococcus pluvialis: A microalgae process model and a techno-economic assessment all through production line.

    NARCIS (Netherlands)

    Panis, Georgios; Rosales Carreon, J.

    2016-01-01

    The freshwater green microalgal strain Haematococcus pluvialis is the richest source for the production of astaxanthin. Astaxanthin is member of the xanthophyll family of carotenoids and constitutes the highest value product derived by microalgae. So far, algal astaxanthin amounts to < 1% of the glo

  14. (-)-Menthol biosynthesis and molecular genetics

    Science.gov (United States)

    Croteau, Rodney B.; Davis, Edward M.; Ringer, Kerry L.; Wildung, Mark R.

    2005-12-01

    (-)-Menthol is the most familiar of the monoterpenes as both a pure natural product and as the principal and characteristic constituent of the essential oil of peppermint ( Mentha x piperita). In this paper, we review the biosynthesis and molecular genetics of (-)-menthol production in peppermint. In Mentha species, essential oil biosynthesis and storage is restricted to the peltate glandular trichomes (oil glands) on the aerial surfaces of the plant. A mechanical method for the isolation of metabolically functional oil glands, has provided a system for precursor feeding studies to elucidate pathway steps, as well as a highly enriched source of the relevant biosynthetic enzymes and of their corresponding transcripts with which cDNA libraries have been constructed to permit cloning and characterization of key structural genes. The biosynthesis of (-)-menthol from primary metabolism requires eight enzymatic steps, and involves the formation and subsequent cyclization of the universal monoterpene precursor geranyl diphosphate to the parent olefin (-)-(4 S)-limonene as the first committed reaction of the sequence. Following hydroxylation at C3, a series of four redox transformations and an isomerization occur in a general “allylic oxidation-conjugate reduction” scheme that installs three chiral centers on the substituted cyclohexanoid ring to yield (-)-(1 R, 3 R, 4 S)-menthol. The properties of each enzyme and gene of menthol biosynthesis are described, as are their probable evolutionary origins in primary metabolism. The organization of menthol biosynthesis is complex in involving four subcellular compartments, and regulation of the pathway appears to reside largely at the level of gene expression. Genetic engineering to up-regulate a flux-limiting step and down-regulate a side route reaction has led to improvement in the composition and yield of peppermint oil.

  15. Manipulation of carbon flux into fatty acid biosynthesis pathway in Dunaliella salina using AccD and ME genes to enhance lipid content and to improve produced biodiesel quality

    Directory of Open Access Journals (Sweden)

    Ahmad Farhad Talebi

    2014-08-01

    Full Text Available Advanced generations of biofuels basically revolve around non-agricultural energy crops. Among those, microalgae owing to its unique characteristics i.e. natural tolerance to waste and saline water, sustainable biomass production and high lipid content (LC, is regarded by many as the ultimate choice for the production of various biofuels such as biodiesel. In the present study, manipulation of carbon flux into fatty acid biosynthesis pathway in Dunaliella salina was achieved using pGH plasmid harboring AccD and ME genes to enhance lipid content and to improve produced biodiesel quality. The stability of transformation was confirmed by PCR after several passages. Southern hybridization of AccD probe with genomic DNA revealed stable integration of the cassette in the specific positions in the chloroplast genome with no read through transcription by indigenous promoters. Comparison of the LC and fatty acid profile of the transformed algal cell line and the control revealed the over-expression of the ME/AccD genes in the transformants leading to 12% increase in total LC and significant improvements in biodiesel properties especially by increasing algal oil oxidation stability. The whole process successfully implemented herein for transforming algal cells by genes involved in lipid production pathway could be helpful for large scale biodiesel production from microalgae.

  16. Putative benefits of microalgal astaxanthin on exercise and human health

    Directory of Open Access Journals (Sweden)

    Marcelo P. Barros

    2011-04-01

    Full Text Available Astaxanthin (ASTA is a pinkish-orange carotenoid produced by microalgae, but also commonly found in shrimp, lobster and salmon, which accumulate ASTA from the aquatic food chain. Numerous studies have addressed the benefits of ASTA for human health, including the inhibition of LDL oxidation, UV-photoprotection and prophylaxis of bacterial stomach ulcers. ASTA is recognized as a powerful scavenger of reactive oxygen species (ROS, especially those involved in lipid peroxidation. Both aerobic and anaerobic exercise are closely related to overproduction of ROS in muscle tissue. Post-exercise inflammatory processes can even exacerbate the oxidative stress imposed by exercise. Thus, ASTA is suggested here as a putative nutritional alternative/coadjutant for antioxidant therapy to afford additional protection to muscle tissues against oxidative damage induced by exercise, as well as for an (overall integrative redox re-balance and general human health.

  17. Lipoteichoic acid induces surfactant protein-A biosynthesis in human alveolar type II epithelial cells through activating the MEK1/2-ERK1/2-NF-κB pathway

    Directory of Open Access Journals (Sweden)

    Liu Feng-Lin

    2012-10-01

    Full Text Available Abstract Background Lipoteichoic acid (LTA, a gram-positive bacterial outer membrane component, can cause septic shock. Our previous studies showed that the gram-negative endotoxin, lipopolysaccharide (LPS, could induce surfactant protein-A (SP-A production in human alveolar epithelial (A549 cells. Objectives In this study, we further evaluated the effect of LTA on SP-A biosynthesis and its possible signal-transducing mechanisms. Methods A549 cells were exposed to LTA. Levels of SP-A, nuclear factor (NF-κB, extracellular signal-regulated kinase 1/2 (ERK1/2, and mitogen-activated/extracellular signal-regulated kinase kinase (MEK1 were determined. Results Exposure of A549 cells to 10, 30, and 50 μg/ml LTA for 24 h did not affect cell viability. Meanwhile, when exposed to 30 μg/ml LTA for 1, 6, and 24 h, the biosynthesis of SP-A mRNA and protein in A549 cells significantly increased. As to the mechanism, LTA enhanced cytosolic and nuclear NF-κB levels in time-dependent manners. Pretreatment with BAY 11–7082, an inhibitor of NF-κB activation, significantly inhibited LTA-induced SP-A mRNA expression. Sequentially, LTA time-dependently augmented phosphorylation of ERK1/2. In addition, levels of phosphorylated MEK1 were augmented following treatment with LTA. Conclusions Therefore, this study showed that LTA can increase SP-A synthesis in human alveolar type II epithelial cells through sequentially activating the MEK1-ERK1/2-NF-κB-dependent pathway.

  18. Glyphosate’s Suppression of Cytochrome P450 Enzymes and Amino Acid Biosynthesis by the Gut Microbiome: Pathways to Modern Diseases

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    Anthony Samsel

    2013-04-01

    Full Text Available Glyphosate, the active ingredient in Roundup®, is the most popular herbicide used worldwide. The industry asserts it is minimally toxic to humans, but here we argue otherwise. Residues are found in the main foods of the Western diet, comprised primarily of sugar, corn, soy and wheat. Glyphosate's inhibition of cytochrome P450 (CYP enzymes is an overlooked component of its toxicity to mammals. CYP enzymes play crucial roles in biology, one of which is to detoxify xenobiotics. Thus, glyphosate enhances the damaging effects of other food borne chemical residues and environmental toxins. Negative impact on the body is insidious and manifests slowly over time as inflammation damages cellular systems throughout the body. Here, we show how interference with CYP enzymes acts synergistically with disruption of the biosynthesis of aromatic amino acids by gut bacteria, as well as impairment in serum sulfate transport. Consequences are most of the diseases and conditions associated with a Western diet, which include gastrointestinal disorders, obesity, diabetes, heart disease, depression, autism, infertility, cancer and Alzheimer’s disease. We explain the documented effects of glyphosate and its ability to induce disease, and we show that glyphosate is the “textbook example” of exogenous semiotic entropy: the disruption of homeostasis by environmental toxins.

  19. Root cap-dependent gravitropic U-turn of maize root requires light-induced auxin biosynthesis via the YUC pathway in the root apex.

    Science.gov (United States)

    Suzuki, Hiromi; Yokawa, Ken; Nakano, Sayuri; Yoshida, Yuriko; Fabrissin, Isabelle; Okamoto, Takashi; Baluška, František; Koshiba, Tomokazu

    2016-08-01

    Gravitropism refers to the growth or movement of plants that is influenced by gravity. Roots exhibit positive gravitropism, and the root cap is thought to be the gravity-sensing site. In some plants, the root cap requires light irradiation for positive gravitropic responses. However, the mechanisms regulating this phenomenon are unknown. We herein report that maize roots exposed to white light continuously for ≥1-2h show increased indole-3-acetic acid (IAA) levels in the root tips, especially in the transition zone (1-3mm from the tip). Treatment with IAA biosynthesis inhibitors yucasin and l-kynurenine prevented any increases in IAA content and root curvature under light conditions. Analyses of the incorporation of a stable isotope label from tryptophan into IAA revealed that some of the IAA in roots was synthesized in the root apex. Furthermore, Zmvt2 and Zmyuc gene transcripts were detected in the root apex. One of the Zmyuc genes (ZM2G141383) was up-regulated by light irradiation in the 0-1mm tip region. Our findings suggest that IAA accumulation in the transition zone is due to light-induced activation of Zmyuc gene expression in the 0-1mm root apex region. Light-induced changes in IAA levels and distributions mediate the maize root gravitropic U-turn. PMID:27307546

  20. Micro-PIXE analysis in invasive ductal carcinoma tissues after treatment of astaxanthin

    International Nuclear Information System (INIS)

    Trace elements play an important role in a number of biological processes. Astaxanthin, a carotoid pigment found in certain marine plant and animals, has shown anti cancer and anti free radical properties. This work intended to understand the effect of Astaxanthin in breast cancer (invasive ductal carcinoma) by using micro-PIXE method. For this aim the concentration of trace elements were compared in healthy, cancerous and cancer treated with astaxanthin in the breast and liver tissues of breast cancer bearing mice, using proton induced X-ray emission. Materials and Methods: Proton induced X-ray emission was used In a study intending to compare the concentration of trace elements in breast and liver tissues of mice bearing tumor, three groups of mice: healthy, cancerous, and cancerous treated by astaxanthin, were considered. Astaxanthin was supplied from Research Institute of women, Alzahra University. Results: Comparing the untreated tumor tissue, treatment with Astaxanthm significantly decreased the amount Fe, P, S, and Ca elements level in tumor tissue of the breast cancer. It is also found that the concentrations of those elements in liver of the untreated mice and the liver of treated mice with astaxanthin were fairly equal. Astaxanthln significantly decrease the accumulation of elements in the site of tumor, and caused the breast cancer cell membrane to lose their desire to collect the elements from healthy tissues. Conclusion: The micro -PIXE technique could calculate elemental concentrations in tissues. Changes in metallic elements may affect microenvironment and cell functions, which might led lead to cell degeneration or death, the results shows that astaxanthin reduces vital element concentration in tumor site, thus it could be used as an anti tumor agent.

  1. Effects of iron electrovalence and species on growth and astaxanthin production of Haematococcus pluvialis

    Science.gov (United States)

    Cai, Minggang; Li, Zhe; Qi, Anxiang

    2009-05-01

    To increase the cell concentration and the accumulation of astaxanthin in the cultivation of Haematococcus pluvialis, effects of different iron electrovalencies (Fe2+-EDTA and Fe3+-EDTA) and species (Fe-EDTA, Fe(OH){x/32x} and FeC6H5O7) addition on cell growth and accumulation of astaxanthin were studied. Results show that different iron electrovalencies have various effects on cell growth and astaxanthin accumulation of H. pluvialis. Compared with Fe3+-EDTA, Fe2+-EDTA stimulate more effectively the formation of astaxanthin. The maximum astaxanthin content (30.70 mg/g biomass cell) was obtained under conditions of 18 μmol/L Fe2+-EDTA, despite the lower cell density (2.3×105 cell/ml) in such condition. Fe3+-EDTA is more effective than Fe2+-EDTA in improving the cell growth. Especially, the maximal steady-state cell density, 2.9×105 cell/ml was obtained at 18 μmol/L Fe3+-EDTA addition. On the other hand, all the various species of iron (EDTA-Fe, Fe(OH){x/32x}, FeC6H5O7) are capable to improve the growth of the algae and astaxanthin production. Among the three iron species, FeC6H5O7 performed the best. Under the condition of a higher concentration (36 μmol/L) of FeC6H5O7, the cell density and astaxanthin production is 2 and 7 times higher than those of iron-limited group, respectively. The present study demonstrates that the effects of the stimulation with different iron species increased in the order of FeC6H5O7, Fe(OH){x/32x} and EDTA-Fe.

  2. Novel bioassay for the discovery of inhibitors of the 2-C-Methyl-D-Erythritol 4-Phosphate (MEP) and terpenoid pathways leading to carotenoid biosynthesis

    Science.gov (United States)

    The 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway leads to the synthesis of isopentenyl-phosphate (IPP) in plastids. It is a major branch point providing precursors for the synthesis of carotenoids, tocopherols, plastoquinone and the phytyl chain of chlorophylls, as well as the hormones abscisi...

  3. Outlining eicosanoid biosynthesis in the crustacean Daphnia

    Directory of Open Access Journals (Sweden)

    Timmermans Martijn JTN

    2008-07-01

    Full Text Available Abstract Background Eicosanoids are biologically active, oxygenated metabolites of three C20 polyunsaturated fatty acids. They act as signalling molecules within the autocrine or paracrine system in both vertebrates and invertebrates mainly functioning as important mediators in reproduction, the immune system and ion transport. The biosynthesis of eicosanoids has been intensively studied in mammals and it is known that they are synthesised from the fatty acid, arachidonic acid, through either the cyclooxygenase (COX pathway; the lipoxygenase (LOX pathway; or the cytochrome P450 epoxygenase pathway. However, little is still known about the synthesis and structure of the pathway in invertebrates. Results Here, we show transcriptomic evidence from Daphnia magna (Crustacea: Branchiopoda together with a bioinformatic analysis of the D. pulex genome providing insight on the role of eicosanoids in these crustaceans as well as outlining a putative pathway of eicosanoid biosynthesis. Daphnia appear only to have one copy of the gene encoding the key enzyme COX, and phylogenetic analysis reveals that the predicted protein sequence of Daphnia COX clusters with other invertebrates. There is no current evidence of an epoxygenase pathway in Daphnia; however, LOX products are most certainly synthesised in daphnids. Conclusion We have outlined the structure of eicosanoid biosynthesis in Daphnia, a key genus in freshwater ecosystems. Improved knowledge of the function and synthesis of eicosanoids in Daphnia and other invertebrates could have important implications for several areas within ecology. This provisional overview of daphnid eicosanoid biosynthesis provides a guide on where to focus future research activities in this area.

  4. Astaxanthin Production by the Red Yeast (Phaffia rhodozyma, Grown on Yeast Extract Addes Coconut Water [PRODUKSI ASTAXANTHIN OLEH KAMIR MERAH (Phaffia Rhodozyma DITUMBUHKAN DALAM AIR KELAPA YANG DITAMBAHKAN EKSTRAK KAMIR

    Directory of Open Access Journals (Sweden)

    V I Meitiniarti

    2003-08-01

    Full Text Available This experiment was conducted to evaluated the effect of yeast extract addition in fresh green coconut water medium during the batch growth and astaxanthin production of Phaffia rhodozyma MUCL 31142. The addition of yeast extract (0,025% and 0,075% could increase the cell growth (37,12 g/l and 49,18 g/l, growth rate (0,061/hour and 0,074/hour, total production of astaxanthin (4,871 mg/l and 9,442 mg/l, specific concentration of astaxanthin (118,99 µg/g biomass, production rate of astaxanthin (0,042/hour and 0,088/hour, astaxanthin yield (0,236 mg/g glucose and 0,342 mg/g glucose, and glocose consumption (19,84 g/l and 26,95 g/l.

  5. Separation of astaxanthin from cells of Phaffia rhodozyma using colloidal gas aphrons in a flotation column.

    Science.gov (United States)

    Dermiki, Maria; Bourquin, Anne Lise; Jauregi, Paula

    2010-01-01

    The aim of this study is to investigate the separation of astaxanthin from the cells of Phaffia rhodozyma using colloidal gas aphrons (CGA), which are surfactant stabilized microbubbles, in a flotation column. It was reported in previous studies that optimum recoveries are achieved at conditions that favor electrostatic interactions. Therefore, in this study, CGA generated from the cationic surfactant hexadecyl trimethyl ammonium bromide (CTAB) were applied to suspensions of cells pretreated with NaOH. The different operation modes (batch or continuous) and the effect of volumetric ratio of CGA to feed, initial concentration of feed, operating height, and flow rate of CGA on the separation of astaxanthin were investigated. The volumetric ratio was found to have a significant effect on the separation of astaxanthin for both batch and continuous experiments. Additionally, the effect of homogenization of the cells on the purity of the recovered fractions was investigated, showing that the homogenization resulted in increased purity. Moreover, different concentrations of surfactant were used for the generation of CGA for the recovery of astaxanthin on batch mode; it was found that recoveries up to 98% could be achieved using CGA generated from a CTAB solution 0.8 mM, which is below the CTAB critical micellar concentration (CMC). These results offer important information for the scale-up of the separation of astaxanthin from the cells of P. rhodozyma using CGA. PMID:19941328

  6. Four different methods comparison for extraction of astaxanthin from green alga Haematococcus pluvialis.

    Science.gov (United States)

    Dong, Shengzhao; Huang, Yi; Zhang, Rui; Wang, Shihui; Liu, Yun

    2014-01-01

    Haematococcus pluvialis is one of the potent organisms for production of astaxanthin. Up to now, no efficient method has been achieved due to its thick cell wall hindering solvent extraction of astaxanthin. In this study, four different methods, hydrochloric acid pretreatment followed by acetone extraction (HCl-ACE), hexane/isopropanol (6:4, v/v) mixture solvents extraction (HEX-IPA), methanol extraction followed by acetone extraction (MET-ACE, 2-step extraction), and soy-oil extraction, were intensively evaluated for extraction of astaxanthin from H. pluvialis. Results showed that HCl-ACE method could obtain the highest oil yield (33.3±1.1%) and astaxanthin content (19.8±1.1%). Quantitative NMR analysis provided the fatty acid chain profiles of total lipid extracts. In all cases, oleyl chains were predominant, and high amounts of polyunsaturated fatty acid chains were observed and the major fatty acid components were oleic acid (13-35%), linoleic acid (37-43%), linolenic acid (20-31%), and total saturated acid (17-28%). DPPH radical scavenging activity of extract obtained by HCl-ACE was 73.2±1.0%, which is the highest amongst the four methods. The reducing power of extract obtained by four extraction methods was also examined. It was concluded that the proposed extraction method of HCl-ACE in this work allowed efficient astaxanthin extractability with high antioxidant properties. PMID:24574909

  7. Four Different Methods Comparison for Extraction of Astaxanthin from Green Alga Haematococcus pluvialis

    Directory of Open Access Journals (Sweden)

    Shengzhao Dong

    2014-01-01

    Full Text Available Haematococcus pluvialis is one of the potent organisms for production of astaxanthin. Up to now, no efficient method has been achieved due to its thick cell wall hindering solvent extraction of astaxanthin. In this study, four different methods, hydrochloric acid pretreatment followed by acetone extraction (HCl-ACE, hexane/isopropanol (6 : 4, v/v mixture solvents extraction (HEX-IPA, methanol extraction followed by acetone extraction (MET-ACE, 2-step extraction, and soy-oil extraction, were intensively evaluated for extraction of astaxanthin from H. pluvialis. Results showed that HCl-ACE method could obtain the highest oil yield (33.3±1.1% and astaxanthin content (19.8±1.1%. Quantitative NMR analysis provided the fatty acid chain profiles of total lipid extracts. In all cases, oleyl chains were predominant, and high amounts of polyunsaturated fatty acid chains were observed and the major fatty acid components were oleic acid (13–35%, linoleic acid (37–43%, linolenic acid (20–31%, and total saturated acid (17–28%. DPPH radical scavenging activity of extract obtained by HCl-ACE was 73.2±1.0%, which is the highest amongst the four methods. The reducing power of extract obtained by four extraction methods was also examined. It was concluded that the proposed extraction method of HCl-ACE in this work allowed efficient astaxanthin extractability with high antioxidant properties.

  8. Extraction of astaxanthin from Euphausia pacific using subcritical 1, 1, 1, 2-tetrafluoroethane

    Science.gov (United States)

    Han, Yuqian; Ma, Qinchuan; Wang, Lan; Xue, Changhu

    2012-12-01

    Euphausia pacific is an important source of natural astaxanthin. Studies were carried out to assess the extractability of astaxanthin from E. pacific using subcritical 1, 1, 1, 2-tetrafluoroethane (R134a). To examine the effects of multiple process variables on the extraction yield, astaxanthin was extracted under various conditions of pressure (30-150 bar), temperature (303-343 K), time (10-50 min), flow rate (2-10 g min-1), moisture content (5.5%-63.61%), and particle size (0.25-0.109 mm). The results showed that the extraction yield increased with temperature, pressure, time and flow rate, but decreased with moisture content and particle size. A maximum yield of 87.74% was obtained under conditions of 100 bar, 333 K, and 30 min with a flow rate of 6 g min-1 and a moisture content of 5.5%. The substantial astaxanthin yield obtained under low-pressure conditions demonstrates that subcritical R134a is a good alternative to CO2 for extraction of astaxanthin from E. pacific.

  9. Arabinogalactan biosynthesis

    DEFF Research Database (Denmark)

    Poulsen, Christian Peter; Dilokpimol, Adiphol; Geshi, Naomi

    2015-01-01

    only to the Golgi cisternae but also to smaller compartments, which may be a part of the unconventional protein secretory pathway in plants. In Poulsen et al.,1 we have demonstrated increased targeting of AtGALT29A to small compartments when Y144 is substituted with another amino acid, and we...... implicated a role for Y144 in the subcellular targeting of AtGALT29A. In this paper, we are presenting another aspect of Y144 substitution in AtGALT29A; namely, Y144A construct demonstrated a 2.5-fold increase while Y144E construct demonstrated a 2-fold decrease in the galactosyltransferase activity of At......), from Arabidopsis thaliana that co-localize with AtGALT31A in the small compartments when expressed transiently in Nicotiana benthamiana. These proteins may play roles in nucleotide sugar metabolism in the small compartments together with arabinogalactan glycosyltransferases....

  10. Astaxanthin Normalizes Epigenetic Modifications of Bovine Somatic Cell Cloned Embryos and Decreases the Generation of Lipid Peroxidation.

    Science.gov (United States)

    Li, R; Wu, H; Zhuo, W W; Mao, Q F; Lan, H; Zhang, Y; Hua, S

    2015-10-01

    Astaxanthin is an extremely common antioxidant scavenging reactive oxygen species (ROS) and blocking lipid peroxidation. This study was conducted to investigate the effects of astaxanthin supplementation on oocyte maturation, and development of bovine somatic cell nuclear transfer (SCNT) embryos. Cumulus-oocyte complexes were cultured in maturation medium with astaxanthin (0, 0.5, 1.0, or 1.5 mg/l), respectively. We found that 0.5 mg/l astaxanthin supplementation significantly increased the proportion of oocyte maturation. Oocytes cultured in 0.5 mg/l astaxanthin supplementation were used to construct SCNT embryos and further cultured with 0, 0.5, 1.0 or 1.5 mg/l astaxanthin. The results showed that the supplementation of 0.5 mg/l astaxanthin significantly improved the proportions of cleavage and blastulation, as well as the total cell number in blastocysts compared with the control group, yet this influence was not concentration dependent. Chromosomal analyses revealed that more blastomeres showed a normal chromosomal complement in 0.5 mg/l astaxanthin treatment group, which was similar to that in IVF embryos. The methylation levels located on the exon 1 of the imprinted gene H19 and IGF2, pluripotent gene OCT4 were normalized, and global DNA methylation, H3K9 and H4K12 acetylation were also improved significantly, which was comparable to that in vitro fertilization (IVF) embryos. Moreover, we also found that astaxanthin supplementation significantly decreased the level of lipid peroxidation. Our findings showed that the supplementation of 0.5 mg/l astaxanthin to oocyte maturation medium and embryo culture medium improved oocyte maturation, SCNT embryo development, increased chromosomal stability and normalized the epigenetic modifications, as well as inhibited overproduction of lipid peroxidation. PMID:26280670

  11. Quantitative analysis of the dynamic signaling pathway involved in the cAMP mediated induction of l-carnitine biosynthesis in E. coli cultures.

    Science.gov (United States)

    Hormiga, José; González-Alcón, Carlos; Sevilla, Angel; Cánovas, Manuel; Torres, Néstor V

    2010-04-01

    L-(-)-carnitine can be synthesized from waste bioprecursors in the form of crotonobetaine. Such biotransformation is carried out in E. coli by the enzymes encoded by operons regulated by the cAMP receptor proteins. Non-phosphorylated sugars, such as glycerol are used as energy and carbon source since glucose inhibits cAMP synthesis. Until now little attention has been paid to the regulatory signaling structure that operates during the transition from a glucose-consuming, non-l-carnitine producing steady state, to a glycerol-consuming l-carnitine producing steady state. In this work we aim to elucidate and quantify the underlying regulatory mechanisms operating in the abolition of the glucose inhibiting effect. For this purpose we make use of the systemic approach by integrating the available information and our own experimentally generated data to construct a mathematical model. The model is built using power-law representation and is used as a platform to make predictive simulations and to assess the consistency of the regulatory structure of the overall process. The model is subsequently checked for quality through stability and a special, dynamic sensitivity analysis. The results show that the model is able to deal with the observed system transient phase. The model is multi-hierarchical, comprising the metabolic, gene expression, signaling and bioreactor levels. It involves variables and parameters of a very different nature that develop in different time scales and orders of magnitude. Some of the most relevant conclusions obtained are: (i) the regulatory interactions among glucose, glycerol and cAMP metabolism are far stronger than those present in the l-carnitine transport, production and degradation processes; (ii) carnitine biosynthesis is very sensitive to the cAMP signaling system since it reacts at very low cAMP receptor concentrations, and (iii) ATP is a critical factor in the transient dynamics. All these model-derived observations have been

  12. Random mutagenesis in Corynebacterium glutamicum ATCC 13032 using an IS6100-based transposon vector identified the last unknown gene in the histidine biosynthesis pathway

    Directory of Open Access Journals (Sweden)

    Gaigalat Lars

    2006-08-01

    Full Text Available Abstract Background Corynebacterium glutamicum, a Gram-positive bacterium of the class Actinobacteria, is an industrially relevant producer of amino acids. Several methods for the targeted genetic manipulation of this organism and rational strain improvement have been developed. An efficient transposon mutagenesis system for the completely sequenced type strain ATCC 13032 would significantly advance functional genome analysis in this bacterium. Results A comprehensive transposon mutant library comprising 10,080 independent clones was constructed by electrotransformation of the restriction-deficient derivative of strain ATCC 13032, C. glutamicum RES167, with an IS6100-containing non-replicative plasmid. Transposon mutants had stable cointegrates between the transposon vector and the chromosome. Altogether 172 transposon integration sites have been determined by sequencing of the chromosomal inserts, revealing that each integration occurred at a different locus. Statistical target site analyses revealed an apparent absence of a target site preference. From the library, auxotrophic mutants were obtained with a frequency of 2.9%. By auxanography analyses nearly two thirds of the auxotrophs were further characterized, including mutants with single, double and alternative nutritional requirements. In most cases the nutritional requirement observed could be correlated to the annotation of the mutated gene involved in the biosynthesis of an amino acid, a nucleotide or a vitamin. One notable exception was a clone mutagenized by transposition into the gene cg0910, which exhibited an auxotrophy for histidine. The protein sequence deduced from cg0910 showed high sequence similarities to inositol-1(or 4-monophosphatases (EC 3.1.3.25. Subsequent genetic deletion of cg0910 delivered the same histidine-auxotrophic phenotype. Genetic complementation of the mutants as well as supplementation by histidinol suggests that cg0910 encodes the hitherto unknown

  13. Bile acid biosynthesis and its regulation

    Directory of Open Access Journals (Sweden)

    Areta Hebanowska

    2010-10-01

    Full Text Available Bile acid biosynthesis is the main pathway of cholesterol catabolism. Bile acids are more soluble than cholesterol so are easier to excrete. As amphipathic molecules they participate in lipid digestion and absorption in the intestine and they help to excrete free cholesterol with bile. They are also ligands for nuclear receptors regulating the expression of genes involved in cholesterol metabolism. Interconversion of cholesterol into bile acids is an important point of its homeostasis. Seventeen enzymes are engaged in this process and many of them are cytochromes P450. Bile acid synthesis initiation may proceed with the “classical” pathway (starting with cholesterol hydroxylation at the C7α position or the “alternative” pathway (starting with cholesterol hydroxylation at the C27 position. Two additional pathways are possible, though their quantitative significance is small (initiated with cholesterol hydroxylations of C24 and C25 positions. Oxysterols produced are not only intermediates of bile acid biosynthesis but also important regulators of metabolism. Bile acid biosynthesis takes place in the liver, but some enzymes are also present in other organs, where they participate in regulation of cholesterol metabolism. Those enzymes are potential targets for new drugs against cholesterol metabolism disturbances. This article is a brief description of the bile acid biosynthesis pathway and participating enzymes.

  14. Biosynthesis of monoterpenoids in higher plants. The biosynthetic pathway leading to the monoterpenoids from amino acids with a carbon-skeleton similar to mevalonic acid

    Energy Technology Data Exchange (ETDEWEB)

    Tange, K. (Hiroshima Univ. (Japan). Faculty of Science)

    1981-09-01

    Radioisotopically labeled L-valine, DL-alanine, sodium acetate, and DL-mevalonic acid were incorporated into linalool by the intact plant of Cinnamomum camphora Sieb. var. linalooliferum Fujita and into geraniol and citronellol by that of Pelargonium roseum Bourbon. The uptake of leucine and valine resulted in the preferential location of the radioactivity on the 3,3-dimethylallyl pyrophosphate-derived moiety of these acyclic monoterpenoids, whereas the uptake of alanine resulted in the preferential location on the isopentenyl pyrophosphate-derived moiety, much as in the cases of mevalonic acid and sodium acetate. A biosynthetic pathway leading to the monoterpenoids from the amino acids is discussed.

  15. Lignification: Flexibility, Biosynthesis and Regulation.

    Science.gov (United States)

    Zhao, Qiao

    2016-08-01

    Lignin is a complex phenolic polymer that is deposited in the secondary cell wall of all vascular plants. The evolution of lignin is considered to be a critical event during vascular plant development, because lignin provides mechanical strength, rigidity, and hydrophobicity to secondary cell walls to allow plants to grow tall and transport water and nutrients over a long distance. In recent years, great research efforts have been made to genetically alter lignin biosynthesis to improve biomass degradability for the production of second-generation biofuels. This global focus on lignin research has significantly advanced our understanding of the lignification process. Based on these advances, here I provide an overview of lignin composition, the biosynthesis pathway and its regulation. PMID:27131502

  16. Analysis of the ergosterol biosynthesis pathway cloning, molecular characterization and phylogeny of lanosterol 14 α-demethylase (ERG11) gene of Moniliophthora perniciosa

    Science.gov (United States)

    de Oliveira Ceita, Geruza; Vilas-Boas, Laurival Antônio; Castilho, Marcelo Santos; Carazzolle, Marcelo Falsarella; Pirovani, Carlos Priminho; Selbach-Schnadelbach, Alessandra; Gramacho, Karina Peres; Ramos, Pablo Ivan Pereira; Barbosa, Luciana Veiga; Pereira, Gonçalo Amarante Guimarães; Góes-Neto, Aristóteles

    2014-01-01

    The phytopathogenic fungus Moniliophthora perniciosa (Stahel) Aime & Philips-Mora, causal agent of witches’ broom disease of cocoa, causes countless damage to cocoa production in Brazil. Molecular studies have attempted to identify genes that play important roles in fungal survival and virulence. In this study, sequences deposited in the M. perniciosa Genome Sequencing Project database were analyzed to identify potential biological targets. For the first time, the ergosterol biosynthetic pathway in M. perniciosa was studied and the lanosterol 14α-demethylase gene (ERG11) that encodes the main enzyme of this pathway and is a target for fungicides was cloned, characterized molecularly and its phylogeny analyzed. ERG11 genomic DNA and cDNA were characterized and sequence analysis of the ERG11 protein identified highly conserved domains typical of this enzyme, such as SRS1, SRS4, EXXR and the heme-binding region (HBR). Comparison of the protein sequences and phylogenetic analysis revealed that the M. perniciosa enzyme was most closely related to that of Coprinopsis cinerea. PMID:25505843

  17. Comparative analysis of astaxanthin and its esters in the mutant E1 of Haematococcus pluvialis and other green algae by HPLC with a C30 column

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A gradient reversed-phase high-performance liquid chromatography (HPLC) method using a C30 col-umn was developed for the simultaneous determination of astaxanthin, astaxanthin monoesters and astaxanthin diesters in the green algae Chlorococcum sp., Chlorella zofingiensis, Haematococcus plu-vialis and the mutant E1, which was obtained from the mutagenesis of H. pluvialis by exposure to UV-irradiation and ethyl methanesulphonate (EMS) with subsequent screening using nicotine. The re-sults showed that the contents of total astaxanthins including free astaxanthin and astaxanthin esters ranged from 1.4 to 30.9 mg/g dry biomass in these green algae. The lower total astaxanthin levels (< 2 mg/g dry biomass) were detected in the green algae Chlorococcum sp. and C. zofingiensis. The higher total astaxanthin levels (>16 mg/g dry biomass) were found in the green alga H. pluvialis and its mutant E1. It is notable that the mutant E1 is found to have considerably higher amounts of total astaxanthin (30.9 mg/g) as compared to the wild strain of H. pluvialis (16.1 mg/g). This indicates that UV-irradiation and EMS compound mutagenesis with subsequent screening using nicotine is an effective method for breeding of a high-producing astaxanthin strain of H. pluvialis. In addition, the green alga C. zofingien-sis had a remarkably higher percentage of astaxanthin diesters (76.3% of total astaxanthins) and a re-markably lower percentage of astaxanthin monoesters (18.0% of total astaxanthins) in comparison with H. pluvialis (35.5% for diesters and 60.9% for monoesters), the mutant E1 (49.1% and 48.1%) and Chlorococcum sp. (18.0% and 58.6%).

  18. Cell-wall disruption and lipid/astaxanthin extraction from microalgae: Chlorella and Haematococcus.

    Science.gov (United States)

    Kim, Dong-Yeon; Vijayan, Durairaj; Praveenkumar, Ramasamy; Han, Jong-In; Lee, Kyubock; Park, Ji-Yeon; Chang, Won-Seok; Lee, Jin-Suk; Oh, You-Kwan

    2016-01-01

    Recently, biofuels and nutraceuticals produced from microalgae have emerged as major interests, resulting in intensive research of the microalgal biorefinery process. In this paper, recent developments in cell-wall disruption and extraction methods are reviewed, focusing on lipid and astaxanthin production from the biotechnologically important microalgae Chlorella and Haematococcus, respectively. As a common, critical bottleneck for recovery of intracellular components such as lipid and astaxanthin from these microalgae, the composition and structure of rigid, thick cell-walls were analyzed. Various chemical, physical, physico-chemical, and biological methods applied for cell-wall breakage and lipid/astaxanthin extraction from Chlorella and Haematococcus are discussed in detail and compared based on efficiency, energy consumption, type and dosage of solvent, biomass concentration and status (wet/dried), toxicity, scalability, and synergistic combinations. This report could serve as a useful guide to the implementation of practical downstream processes for recovery of valuable products from microalgae including Chlorella and Haematococcus. PMID:26342788

  19. Recovery of astaxanthin from discharged wastewater during the production of chitin

    Science.gov (United States)

    Chen, Xiaolin; Yang, Shengfeng; Xing, Ronge; Yu, Huahua; Liu, Song; Li, Pengcheng

    2012-06-01

    In this paper, studies were carried out to extract astaxanthin from discharged wastewater during the production of chitin and to reveal the scavenging effect of the obtained pigment on 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical. Different ratios of dichloromethane/methanol (V/V) were used to extract astaxanthin. When the ratio of dichloromethane/methanol was 2:8 and the ratio between the mixed organic solvent (dichloromethane/methanol, 2:8, V/V) and wastewater was 1:1, the highest yield of pigment was obtained (8.4 mg/50 mL). The concentration of free astaxanthin in the obtained pigment analyzed by HPLC was 30.02%. The obtained pigment possessed strong scavenging ability on DPPH radical and IC50 was 0.84mg/ml.

  20. Effects of Astaxanthin from Litopenaeus Vannamei on Carrageenan-Induced Edema and Pain Behavior in Mice

    Directory of Open Access Journals (Sweden)

    Zulkiflee Kuedo

    2016-03-01

    Full Text Available Carrageenan produces both inflammation and pain when injected in mouse paws via enhancement of reactive oxygen species formation. We have investigated an effect of astaxanthin extracted from Litopenaeus vannamei in carrageenan-induced mice paw edema and pain. The current study demonstrates interesting effects from astaxanthin treatment in mice: an inhibition of paw edema induced in hind paw, an increase in mechanical paw withdrawal threshold and thermal paw withdrawal latency, and a reduction in the amount of myeloperoxidase enzyme and lipid peroxidation products in the paw. Furthermore the effect was comparable to indomethacin, a standard treatment for inflammation symptoms. Due to adverse effects of indomethacin on cardiovascular and gastrointestinal systems, our study suggests promising prospect of astaxanthin extract as an anti-inflammatory alternative against carrageenan-induced paw edema and pain behavior.

  1. Prediction of ROA and ECD Related to Conformational Changes of Astaxanthin Enantiomers.

    Science.gov (United States)

    Zajac, Grzegorz; Kaczor, Agnieszka; Buda, Szymon; Młynarski, Jacek; Frelek, Jadwiga; Dobrowolski, Jan Cz; Baranska, Małgorzata

    2015-09-17

    ECD, ROA, and VCD were used to characterize astaxanthin conformers that differ in their arrangements of the β-ionone ring in respect to the chain. We obtained ECD spectra experimentally, and the ECD, ROA, and VCD spectra of both individual conformers and conformation-averaged mixtures were predicted using quantum-chemical calculations at the CAM-B3LYP level of theory using the PCM solvation model. The chiroptical methods employed (particularly ECD and ROA) were considerably more sensitive to conformational changes of astaxanthin compared to "mono-signed" conventional Raman spectroscopy. Strikingly, conformers that are the same optical isomers (e.g., of 3S,3'S-astxanthin), while geometrically nearly mirror images, exhibited sign-inversed ECD and ROA spectra. The conformational sensitivity of these chiroptical methods makes them a promising tool in the study of carotenoids in the natural environment (for instance, in de novo algal or yeast astaxanthin sources). PMID:26305416

  2. Cytotoxic Induction and Photoacoustic Imaging of Breast Cancer Cells Using Astaxanthin-Reduced Gold Nanoparticles

    Directory of Open Access Journals (Sweden)

    Subramaniyan Bharathiraja

    2016-04-01

    Full Text Available Astaxanthin, a kind of photosynthetic pigment, was employed for gold nanoparticle formation. Nanoparticles were characterized using Ulteraviolet-Visible (UV-Vis spectroscopy, transmission electron microscopy, and X-ray diffraction, and the possible presence of astaxanthin functional groups were analyzed by Fourier transform infrared spectroscopy (FTIR. The cytotoxic effect of synthesized nanoparticles was evaluated against MDA-MB-231 (human breast cancer cells using a tetrazolium-based assay, and synthesized nanoparticles exhibited dose-dependent toxicity. The morphology upon cell death was differentiated through fluorescent microscopy using different stains that predicted apoptosis. The synthesized nanoparticles were applied in ultrasound-coupled photoacoustic imaging to obtain good images of treated cells. Astaxanthin-reduced gold nanoparticle has the potential to act as a promising agent in the field of photo-based diagnosis and therapy.

  3. Effects of Astaxanthin from Litopenaeus Vannamei on Carrageenan-Induced Edema and Pain Behavior in Mice.

    Science.gov (United States)

    Kuedo, Zulkiflee; Sangsuriyawong, Anantita; Klaypradit, Wanwimol; Tipmanee, Varomyalin; Chonpathompikunlert, Pennapa

    2016-01-01

    Carrageenan produces both inflammation and pain when injected in mouse paws via enhancement of reactive oxygen species formation. We have investigated an effect of astaxanthin extracted from Litopenaeus vannamei in carrageenan-induced mice paw edema and pain. The current study demonstrates interesting effects from astaxanthin treatment in mice: an inhibition of paw edema induced in hind paw, an increase in mechanical paw withdrawal threshold and thermal paw withdrawal latency, and a reduction in the amount of myeloperoxidase enzyme and lipid peroxidation products in the paw. Furthermore the effect was comparable to indomethacin, a standard treatment for inflammation symptoms. Due to adverse effects of indomethacin on cardiovascular and gastrointestinal systems, our study suggests promising prospect of astaxanthin extract as an anti-inflammatory alternative against carrageenan-induced paw edema and pain behavior. PMID:27007359

  4. Astaxanthin protecting membrane integrity against photosensitized oxidation through synergism with other carotenoids

    DEFF Research Database (Denmark)

    Du, Hui-Hui; Liang, Ran; Han, Rui-Min;

    2015-01-01

    using optical microscopy and digital image heterogeneity analysis. The lowest initial rate of GUV budding after the lag phase was seen for GUVs with astaxanthin as the least reducing carotenoid, while the lowest final level of entropy appeared for those with lycopene or β-carotene as a more reducing...... carotenoid. The combination of astaxanthin and lycopene gave optimal protection against budding with respect to both a longer lag phase and lower final level of entropy by combining good electron acceptance and good electron donation. Quenching of singlet oxygen by carotenoids close to chlorophyll...... a in the membrane interior in parallel with scavenging of superoxide radicals by astaxanthin anchored in the surface may explain the synergism between carotenoids involving both type I and type II photosensitization by chlorophyll a....

  5. Isolation and optimization of production of Astaxanthin from Antarctic yeast Rhodotorula sp.NJ298

    Institute of Scientific and Technical Information of China (English)

    Liu Junling; Miao Jinlai; Sun Xiuqin; Wang Quanfu; Li Guangyou

    2007-01-01

    Rhodotorula sp. NJ298 which could produce carotenoids was isolated from Antarctic sea ice. The major carotenoid was identified as astaxanthin by Liquid Chromatography/Mass Spectrometry(LC/MS), and its content accounted for 87.62% of total carotenoids (1,786 μg/g). High Performance Liquid Chromatogrephy(HPLC)analysis showed that the purity of the astaxanthin reached about 96.16% through a simple purification. Maximum astaxanthin production(1,908/μg/g)was obtained when the yeast was grown at 10℃ in seawater medium containing 5g/L sodium acetate, 5g/L peptone, 0.5g/L NaCl, 0.01g/L KH2P04;0.01g/L MgS04·7H2O and 0.001 g/L FeS04·7H20 at pH 7.5.

  6. Carbon-dependent control of electron transfer and central carbon pathway genes for methane biosynthesis in the Archaean, Methanosarcina acetivorans strain C2A

    Directory of Open Access Journals (Sweden)

    Gunsalus Robert P

    2010-02-01

    Full Text Available Abstract Background The archaeon, Methanosarcina acetivorans strain C2A forms methane, a potent greenhouse gas, from a variety of one-carbon substrates and acetate. Whereas the biochemical pathways leading to methane formation are well understood, little is known about the expression of the many of the genes that encode proteins needed for carbon flow, electron transfer and/or energy conservation. Quantitative transcript analysis was performed on twenty gene clusters encompassing over one hundred genes in M. acetivorans that encode enzymes/proteins with known or potential roles in substrate conversion to methane. Results The expression of many seemingly "redundant" genes/gene clusters establish substrate dependent control of approximately seventy genes for methane production by the pathways for methanol and acetate utilization. These include genes for soluble-type and membrane-type heterodisulfide reductases (hdr, hydrogenases including genes for a vht-type F420 non-reducing hydrogenase, molybdenum-type (fmd as well as tungsten-type (fwd formylmethanofuran dehydrogenases, genes for rnf and mrp-type electron transfer complexes, for acetate uptake, plus multiple genes for aha- and atp-type ATP synthesis complexes. Analysis of promoters for seven gene clusters reveal UTR leaders of 51-137 nucleotides in length, raising the possibility of both transcriptional and translational levels of control. Conclusions The above findings establish the differential and coordinated expression of two major gene families in M. acetivorans in response to carbon/energy supply. Furthermore, the quantitative mRNA measurements demonstrate the dynamic range for modulating transcript abundance. Since many of these gene clusters in M. acetivorans are also present in other Methanosarcina species including M. mazei, and in M. barkeri, these findings provide a basis for predicting related control in these environmentally significant methanogens.

  7. Specific light uptake rates can enhance astaxanthin productivity in Haematococcus lacustris.

    Science.gov (United States)

    Lee, Ho-Sang; Kim, Z-Hun; Park, Hanwool; Lee, Choul-Gyun

    2016-05-01

    Lumostatic operation was applied for efficient astaxanthin production in autotrophic Haematococcus lacustris cultures using 0.4-L bubble column photobioreactors. The lumostatic operation in this study was performed with three different specific light uptake rates (q e) based on cell concentration, cell projection area, and fresh weight as one-, two- and three-dimensional characteristics values, respectively. The q e value from the cell concentration (q e1D) obtained was 13.5 × 10(-8) μE cell(-1) s(-1), and the maximum astaxanthin concentration was increased to 150 % compared to that of a control with constant light intensity. The other optimum q e values by cell projection area (q e2D) and fresh weight (q e3D) were determined to be 195 μE m(-2) s(-1) and 10.5 μE g(-1) s(-1) for astaxanthin production, respectively. The maximum astaxanthin production from the lumostatic cultures using the parameters controlled by cell projection area (2D) and fresh weight (3D) also increased by 36 and 22 % over that of the controls, respectively. When comparing the optimal q e values among the three different types, the lumostatic cultures using q e based on fresh weight showed the highest astaxanthin productivity (22.8 mg L(-1) day(-1)), which was a higher level than previously reported. The lumostatic operations reported here demonstrated that more efficient and effective astaxanthin production was obtained by H. lacustris than providing a constant light intensity, regardless of which parameter is used to calculate the specific light uptake rate. PMID:26873706

  8. Combined conventional/antioxidant "Astaxanthin" treatment for male infertility: a double blind, randomized trial

    Institute of Scientific and Technical Information of China (English)

    F. H. Comhaire; Y. El Garem; A. Mahmoud; F. Eertmans; F. Schoonjans

    2005-01-01

    Aim: To evaluate the treatment of male infertility with a strong natural antioxidant, in addition to conventional treatment.Methods: Using a double blind, randomized trial design, 30 men with infertility of ≥12 months and female partners with no demonstrable cause of infertility received conventional treatment according to the guidelines of the World Health Organization (WHO), and either a strong antioxidant Astaxanthin 16 mg/day (AstaCarox(R), AstaReal AB,Gustavsberg, Sweden) or placebo for 3 months. The effects of treatment on semen parameters, reactive oxygen species (ROS), zona-free hamster oocyte test, serum hormones including testosterone, luteinizing hormone (LH),follicle stimulating hormone (FSH) and Inhibin B, and spontaneous or intrauterine insemination (IUI)-induced pregnancies were evaluated. Results: ROS and Inhibin B decreased significantly and sperm linear velocity increased in the Astaxanthin group (n = 11), but not in the placebo group (n = 19). The results of the zona-free hamster oocyte test tended to improve in the Astaxanthin group in contrast with the placebo group, though not reaching statistical significance.The total and per cycle pregnancy rates among the placebo cases (10.5 % and 3.6 %) were lower compared with 54.5 % and 23.1% respectively in the Astaxanthin group (P = 0.028; P = 0.036). Conclusion: Although the present study suggests a positive effect of Astaxanthin on sperm parameters and fertility, the results need to be confirmed in a larger trial before recommending Astaxanthin for the complementary treatment of infertile men.

  9. Biosynthesis of diplosporin by Diplodia macrospora: Pt. 3

    International Nuclear Information System (INIS)

    The biosynthesis of diplosporin, a metabolite of Diplodia macrospora, was investigated using 18O2 gas as precursor. A related metabolite, (5R)-diplosporin, was isolated and characterized. A biosynthetic pathway is proposed for diplosporin

  10. Coordinated expression of two key enzyme genes pheA and aroF in phenylalanine biosynthesis pathway%苯丙氨酸生物合成关键酶基因pheA与aroF协同表达

    Institute of Scientific and Technical Information of China (English)

    芦佳; 黄坤央; 赵越; 徐琪寿; 郭军; 黄英武

    2012-01-01

    Objective:To develop a metabolically engineered E..coli strain for the overproduction of L-phenylalanine through optimization of protein expressions of two key genes pheA and aroF involved in L-phenylalanine biosynthesis pathway.Methods:We constructed two recombinant plasmids pZEI2-RBS-AF and pZE12-AF based on designing the DNA sequences of intergenic regulatory region between pheA and aroF.PheA and aroF protein expressions were observed by SDS-PAGE.Engineered E.coli strains were obtained by transforming the above two plasmids into an auxotrophic strain MGA and fermented for L- phenylalanine production.ResuLts: L- phenylalanine yield of the engineered strain MG△pZE12-AF was almost twice as high as that of the engineered strain MG△pZE12 -RBS-AR It was achieved by coordinated tandem expression of pheA and aroR Conclusion: Coordinated expression of L- phenylalanine biosynthesis enzymes can be obtained by adjusting intergenic regulatory sequences between tandem enzyme genes. It provides a new approach to improve the yield of engineered L-phenylalanine producing strain.%目的:优化L-苯丙氨酸生物合成通路上的关键酶基因pheA、aroF的蛋白表达,构建高产L-苯丙氨酸的工程菌株。方法:通过设计酶基因的间隔调控序列,分别构建重组质粒pZE12-RBS—AF和pZE12-AF,SDS—PAGE观察蛋白表达量,转入营养缺陷菌MGA中构建工程菌,并发酵培养。结果:工程菌MG△pZE12-AF苯丙氨酸的产量比工程菌MG△pZE12-RBs—AF高1倍,实现了L-苯丙氨酸生物合成关键酶基因pheA和aroF协同,匹配表达。结论:调整串联酶基因之间的间隔调控序列可实现苯丙氨酸合成酶基因的协同表达,提供了-种新的提高苯丙氨酸工程菌产量的方法。

  11. Histidine biosynthesis, its regulation and biotechnological application in Corynebacterium glutamicum

    OpenAIRE

    Kulis-Horn, Robert K; Persicke, Marcus; Kalinowski, Jörn

    2013-01-01

    l-Histidine biosynthesis is an ancient metabolic pathway present in bacteria, archaea, lower eukaryotes, and plants. For decades l-histidine biosynthesis has been studied mainly in Escherichia coli and Salmonella typhimurium, revealing fundamental regulatory processes in bacteria. Furthermore, in the last 15 years this pathway has been also investigated intensively in the industrial amino acid-producing bacterium Corynebacterium glutamicum, revealing similarities to E. coli and S. typhimurium...

  12. Combinatorial biosynthesis of medicinal plant secondary metabolites

    NARCIS (Netherlands)

    Julsing, Mattijs K.; Koulman, Albert; Woerdenbag, Herman J.; Quax, Wim J.; Kayser, Oliver

    2006-01-01

    Combinatorial biosynthesis is a new tool in the generation of novel natural products and for the production of rare and expensive natural products. The basic concept is combining metabolic pathways in different organisms on a genetic level. As a consequence heterologous organisms provide precursors

  13. The Sorghum Gene for Leaf Color Changes upon Wounding (P Encodes a Flavanone 4-Reductase in the 3-Deoxyanthocyanidin Biosynthesis Pathway

    Directory of Open Access Journals (Sweden)

    Hiroyuki Kawahigashi

    2016-05-01

    Full Text Available Upon wounding or pathogen invasion, leaves of sorghum [Sorghum bicolor (L. Moench] plants with the P gene turn purple, whereas leaves with the recessive allele turn brown or tan. This purple phenotype is determined by the production of two 3-deoxyanthocyanidins, apigeninidin and luteolinidin, which are not produced by the tan-phenotype plants. Using map-based cloning in progeny from a cross between purple Nakei-MS3B (PP and tan Greenleaf (pp cultivars, we isolated this gene, which was located in a 27-kb genomic region around the 58.1 Mb position on chromosome 6. Four candidate genes identified in this region were similar to the maize leucoanthocyanidin reductase gene. None of them was expressed before wounding, and only the Sb06g029550 gene was induced in both cultivars after wounding. The Sb06g029550 protein was detected in Nakei-MS3B, but only slightly in Greenleaf, in which it may be unstable because of a Cys252Tyr substitution. A recombinant Sb06g029550 protein had a specific flavanone 4-reductase activity, and converted flavanones (naringenin or eriodictyol to flavan-4-ols (apiforol or luteoforol in vitro. Our data indicate that the Sb06g029550 gene is involved in the 3-deoxyanthocyanidin synthesis pathway.

  14. The Sorghum Gene for Leaf Color Changes upon Wounding (P) Encodes a Flavanone 4-Reductase in the 3-Deoxyanthocyanidin Biosynthesis Pathway.

    Science.gov (United States)

    Kawahigashi, Hiroyuki; Kasuga, Shigemitsu; Sawada, Yuji; Yonemaru, Jun-Ichi; Ando, Tsuyu; Kanamori, Hiroyuki; Wu, Jianzhong; Mizuno, Hiroshi; Momma, Mitsuru; Fujimoto, Zui; Hirai, Masami Yokota; Matsumoto, Takashi

    2016-01-01

    Upon wounding or pathogen invasion, leaves of sorghum [Sorghum bicolor (L.) Moench] plants with the P gene turn purple, whereas leaves with the recessive allele turn brown or tan. This purple phenotype is determined by the production of two 3-deoxyanthocyanidins, apigeninidin and luteolinidin, which are not produced by the tan-phenotype plants. Using map-based cloning in progeny from a cross between purple Nakei-MS3B (PP) and tan Greenleaf (pp) cultivars, we isolated this gene, which was located in a 27-kb genomic region around the 58.1 Mb position on chromosome 6. Four candidate genes identified in this region were similar to the maize leucoanthocyanidin reductase gene. None of them was expressed before wounding, and only the Sb06g029550 gene was induced in both cultivars after wounding. The Sb06g029550 protein was detected in Nakei-MS3B, but only slightly in Greenleaf, in which it may be unstable because of a Cys252Tyr substitution. A recombinant Sb06g029550 protein had a specific flavanone 4-reductase activity, and converted flavanones (naringenin or eriodictyol) to flavan-4-ols (apiforol or luteoforol) in vitro Our data indicate that the Sb06g029550 gene is involved in the 3-deoxyanthocyanidin synthesis pathway. PMID:26994288

  15. Astaxanthin Production by the Red Yeast (Phaffia rhodozyma), Grown on Yeast Extract Addes Coconut Water [PRODUKSI ASTAXANTHIN OLEH KAMIR MERAH (Phaffia Rhodozyma) DITUMBUHKAN DALAM AIR KELAPA YANG DITAMBAHKAN EKSTRAK KAMIR

    OpenAIRE

    V I Meitiniarti; Ana W Purnomo; K H Timotius

    2003-01-01

    This experiment was conducted to evaluated the effect of yeast extract addition in fresh green coconut water medium during the batch growth and astaxanthin production of Phaffia rhodozyma MUCL 31142. The addition of yeast extract (0,025% and 0,075%) could increase the cell growth (37,12 g/l and 49,18 g/l), growth rate (0,061/hour and 0,074/hour), total production of astaxanthin (4,871 mg/l and 9,442 mg/l), specific concentration of astaxanthin (118,99 µg/g biomass), production rate of asta...

  16. Astaxanthin Alleviates Early Brain Injury Following Subarachnoid Hemorrhage in Rats: Possible Involvement of Akt/Bad Signaling

    Directory of Open Access Journals (Sweden)

    Xiang-Sheng Zhang

    2014-07-01

    Full Text Available Apoptosis has been proven to play a crucial role in early brain injury pathogenesis and to represent a target for the treatment of subarachnoid hemorrhage (SAH. Previously, we demonstrated that astaxanthin (ATX administration markedly reduced neuronal apoptosis in the early period after SAH. However, the underlying molecular mechanisms remain obscure. In the present study, we tried to investigate whether ATX administration is associated with the phosphatidylinositol 3-kinase-Akt (PI3K/Akt pathway, which can play an important role in the signaling of apoptosis. Our results showed that post-SAH treatment with ATX could cause a significant increase of phosphorylated Akt and Bad levels, along with a significant decrease of cleaved caspase-3 levels in the cortex after SAH. In addition to the reduced neuronal apoptosis, treatment with ATX could also significantly reduce secondary brain injury characterized by neurological dysfunction, cerebral edema and blood-brain barrier disruption. In contrast, the PI3K/Akt inhibitor, LY294002, could partially reverse the neuroprotection of ATX in the early period after SAH by downregulating ATX-induced activation of Akt/Bad and upregulating cleaved caspase-3 levels. These results provided the evidence that ATX could attenuate apoptosis in a rat SAH model, potentially, in part, through modulating the Akt/Bad pathway.

  17. Response Surface Methodology for Ultrasound-Assisted Extraction of Astaxanthin from Haematococcus pluvialis

    Directory of Open Access Journals (Sweden)

    Hong-Fu Wu

    2013-05-01

    Full Text Available Astaxanthin is a novel carotenoid nutraceutical occurring in many crustaceans and red yeasts. It has exhibited various biological activities including prevention or amelioration of cardiovascular disease, gastric ulcer, hypertension, and diabetic nephropathy. In this study, ultrasound-assisted extraction was developed for the effective extraction of astaxanthin from Haematococcus pluvialis. Some parameters such as extraction solvent, liquid-to-solid ratio, extraction temperature, and extraction time were optimized by single-factor experiment and response surface methodology. The optimal extraction conditions were 48.0% ethanol in ethyl acetate, the liquid-to-solid ratio was 20:1 (mL/g, and extraction for 16.0 min at 41.1 °C under ultrasound irradiation of 200 W. Under optimal conditions, the yield of astaxanthin was 27.58 ± 0.40 mg/g. The results obtained are beneficial for the full utilization of Haematococcus pluvialis, which also indicated that ultrasound-assisted extraction is a very useful method for extracting astaxanthin from marine life.

  18. Stability of astaxanthin in yogurt used to simulate apricot color, under refrigeration

    Directory of Open Access Journals (Sweden)

    Pedro Cerezal Mezquita

    2014-09-01

    Full Text Available The aim of this study was to incorporate astaxanthin to yogurts with different fat content to match apricot (Prunus armeniaca L. color. The samples containing astaxanthin were stored at 5 ± 3 °C, and color stability and astaxanthin content were determined by colorimetry and high performance liquid chromatography (HPLC, respectively. Yogurt samples were analyzed in triplicate every 24 hours for one week and subsequently every week for 3 more weeks There were no significant differences (p < 0.05 between astaxanthin concentration values at 0 and 28 days for both samples; therefore, it can be said that the fat content in the yogurt had not effect on the stability of pigment. The low dispersion of the data showed uniformity in the three chromaticity coordinates L*, a*, b* throughout the storage period for both types of yogurt. Values of ∆E ≥ 5.0 were not obtained at any time during storage, indicating high stability of the pigment.

  19. PCR-based method for the rapid identification of astaxanthin-accumulating yeasts (Phaffia spp.).

    Science.gov (United States)

    Colabella, Fernando; Libkind, Diego

    2016-01-01

    It has been recently found that the natural distribution, habitat, and genetic diversity of astaxanthin-producing yeasts (i.e. Phaffia rhodozyma, synonym Xanthophyllomyces dendrorhous) is much greater than previously thought. P. rhodozyma is biotechnologically exploited due to its ability to produce the carotenoid pigment astaxanthin and thus, it is used as a natural source of this pigment for aquaculture. P. rhodozyma was also capable of synthesizing the potent UVB sunscreen mycosporine-glutaminol-glucoside (MGG). Therefore, further environmental studies are needed to elucidate its ecological aspects and detect new potential strains for the production of astaxanthin and MGG. However, obtaining new isolates of P. rhodozyma and related species is not always easy due to its low abundance and the presence of other sympatric and pigmented yeasts. In this work we report a successful development of a species-specific primer which has the ability to quickly and accurately detecting isolates representing all known lineages of the genus Phaffia (including novel species of the genus) and excluding closely related taxa. For this purpose, a primer of 20 nucleotides (called PhR) was designed to be used in combination with universal primers ITS3 and NL4 in a multiplex amplification. The proposed method has the sensitivity and specificity required for the precise detection of new isolates, and therefore represents an important tool for the environmental search for novel astaxanthin-producing yeasts. PMID:26922472

  20. Astaxanthin Protecting Membrane Integrity against Photosensitized Oxidation through Synergism with Other Carotenoids.

    Science.gov (United States)

    Du, Hui-Hui; Liang, Ran; Han, Rui-Min; Zhang, Jian-Ping; Skibsted, Leif H

    2015-10-21

    Incorporation of astaxanthin or zeaxanthin in giant unilamellar vesicles (GUVs) of phosphatidylcholine resulted in a longer lag phase than incorporation of β-carotene or lycopene for the onset of budding induced by chlorophyll a photosensitization and quantified by a dimensionless entropy parameter using optical microscopy and digital image heterogeneity analysis. The lowest initial rate of GUV budding after the lag phase was seen for GUVs with astaxanthin as the least reducing carotenoid, while the lowest final level of entropy appeared for those with lycopene or β-carotene as a more reducing carotenoid. The combination of astaxanthin and lycopene gave optimal protection against budding with respect to both a longer lag phase and lower final level of entropy by combining good electron acceptance and good electron donation. Quenching of singlet oxygen by carotenoids close to chlorophyll a in the membrane interior in parallel with scavenging of superoxide radicals by astaxanthin anchored in the surface may explain the synergism between carotenoids involving both type I and type II photosensitization by chlorophyll a. PMID:26429551

  1. 75 FR 5887 - Listing of Color Additives Exempt From Certification; Astaxanthin Dimethyldisuccinate...

    Science.gov (United States)

    2010-02-05

    ... the final rule published in the Federal Register of November 5, 2009 (74 FR 57248) is confirmed as...-436-1264. SUPPLEMENTARY INFORMATION: In the Federal Register of November 5, 2009 (74 FR 57248), FDA... Color Additives Exempt From Certification; Astaxanthin Dimethyldisuccinate; Confirmation of...

  2. A developmental toxicity study of 3S, 3'S-Astaxanthin in New Zealand white rabbits.

    Science.gov (United States)

    Schneider, Steffen; Mellert, Werner; Schulte, Stefan; van Ravenzwaay, Bennard

    2016-04-01

    Astaxanthin, a naturally occurring pigment used to give the characteristic orange-pink colour to salmonid fish reared in aquaculture, is also marketed as a dietary supplement. Synthetic 3S, 3'S-Astaxanthin was tested for potential harmful effects on the in utero development of New Zealand white rabbits in a study according to international regulatory guidelines. There were two control groups, one being a placebo administration and three dose levels corresponding to 100, 200, and 400 mg of 3S, 3'S-Astaxanthin per kg body weight/day. The group sizes varied from 23 to 27 litters, providing approximately 200 fetuses per group for evaluation of developmental toxicity. There were no significant effects on the health of the does, nor on the size and viability of the litters. Malformations, both external and internal, were rare and occurred in all groups, including controls with no indication of a treatment relationship. Variations were much more common, being found in all litters. However, when examined by type and frequency, no pattern emerged indicating a relationship to administration of the test substance. It is concluded that administration of 3S, 3'S-Astaxanthin in a gelatin/carbohydrate powder formulation throughout pregnancy up to 400 mg/kg body weight/day is without harmful effects on reproduction or fetal development. PMID:26854919

  3. Gastric inflammatory markers and interleukins in patients with functional dyspepsia treated with astaxanthin

    DEFF Research Database (Denmark)

    Andersen, L.P.; Holck, Susanne; Kupcinskas, L.;

    2007-01-01

    The chronic active inflammation caused by Helicobacter pylori is dominated by neutrophils, macrophages, lymphocytes and plasma cells. Several interleukins are involved in the inflammatory process. The aim of this study was to investigate the effect of astaxanthin on gastric inflammation in patien...

  4. Gene expression profile analysis in astaxanthin-induced Haematococcus pluvialis using a cDNA microarray.

    Science.gov (United States)

    Eom, Hyunsuk; Lee, Choul-Gyun; Jin, EonSeon

    2006-05-01

    The unicellular green alga Haematococcus pluvialis (Volvocales) is known for the ketocarotenoid astaxanthin (3, 3'-dihydroxy-beta, beta-carotene-4, 4'-dione) accumulation, which is induced under unfavorable culture conditions. In this work, we used cDNA microarray analysis to screen differentially expressed genes in H. pluvialis under astaxanthin-inductive culture conditions, such as combination of cell exposure to high irradiance and nutrient deprivation. Among the 965 genes in the cDNA array, there are 144 genes exhibiting differential expression (twofold changes) under these conditions. A significant decrease in the expression of photosynthesis-related genes was shown in astaxanthin-accumulating cells (red cells). Defense- or stress-related genes and signal transduction genes were also induced in the red cells. A comparison of microarray and real-time PCR analysis showed good correlation between the differentially expressed genes by the two methods. Our results indicate that the cDNA microarray approach, as employed in this work, can be relied upon and used to monitor gene expression profiles in H. pluvialis. In addition, the genes that were differentially expressed during astaxanthin induction are suitable candidates for further study and can be used as tools for dissecting the molecular mechanism of this unique pigment accumulation process in the green alga H. pluvialis. PMID:16320067

  5. Effect of feeding methods on the astaxanthin production by Phaffia rhodozyma in fed-batch process

    Directory of Open Access Journals (Sweden)

    Danilo Gomes Moriel

    2005-05-01

    Full Text Available The effect of feeding methods on the production of astaxanthin by the yeast Phaffia rhodozyma ATCC 24202 was studied, using continuous and pulsed fed-batch processes and low cost materials as substrates (sugar cane juice and urea. In continuous fed-batch processes, a cellular astaxanthin concentration of 383.73 µg/g biomass was obtained. But in pulsed fed-batch processes a reduction in the cellular astaxanthin concentration (303.34 µg/g biomass was observed. Thus the continuous fed-batch processes could be an alternative to industrial production of astaxanthin, allowing an increase in the biomass productivity without losses on astaxanthin production by the yeast.O efeito da alimentação na produção de astaxantina pela levedura Phaffia rhodozyma ATCC 24202 foi estudado, utilizando processos descontínuo alimentado com alimentação contínua e intermitente, e matérias-primas de baixo custo como substratos (caldo de cana de açúcar e uréia. Em processos descontínuo alimentado com alimentação contínua, uma concentração celular de astaxantina de 383,73 µg/g biomassa foi obtida. Entretanto, em processos descontínuo alimentado com alimentação intermitente, uma redução na concentração celular de astaxantina (303,34 µg/g biomassa foi observada. Desta forma, processos descontínuo alimentado com alimentação contínua poderiam ser uma alternativa na produção industrial de astaxantina, permitindo um aumento na produtividade de biomassa sem perdas na produção de astaxantina pela levedura.

  6. BIOSYNTHESIS OF NANOPARTICLES

    Directory of Open Access Journals (Sweden)

    S. Sen

    2011-11-01

    Full Text Available Biosynthesis of nanoparticles is reviewed in detail in this study. Comparison of different synthesis methods, namely physical, chemical and green methods giving emphasis to biological synthesis is documented here. This study also details limitations of the present techniques and envisages the future scope of nanoparticle biosynthesis. Important applications of nanoparticles are also discussed briefly in the present report.

  7. Effect of dietary Astaxanthin sources supplementation on muscle pigmentation and lipid peroxidation in rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Marco Saroglia

    2010-01-01

    Full Text Available Astaxanthin is one of the major carotenoids in aquatic animals including salmonid fishes and is the preferred pigments added to salmon feed. It’s also a powerful antioxidant compared to other carotenoids and that may confer numerous health benefits. The aim of the present experi- ment was to investigate the effect of Astaxanthin deposition on the lipids peroxidation by studying the Malondialdeide (MDA level in muscle of rainbow trout (Oncorhynchus mykiss. The Astaxanthin concentrations in fish fed with a commercial sources as Lucantin®Pink (BASF Ludwigshafen, Ger- many reached values to 5.76±0.18x10-3 mg/g after 50 days feeding, while the MDA concentration de- creased from 1.56x103 to 0.45x103 ng/g. The correlation between MDA and Astaxanthin concentrations decreased linearly and confirmed the antioxidant properties of the pigment by reducing the lipids peroxidation.

  8. LC-MS/APCI identification of glucoside esters and diesters of astaxanthin from the snow alga Chlamydomonas nivalis including their optical stereoisomers.

    Science.gov (United States)

    Řezanka, Tomáš; Nedbalová, Linda; Kolouchová, Irena; Sigler, Karel

    2013-04-01

    HPLC methods (LC-MS/APCI and chiral HPLC) were used for the identification of astaxanthin derivatives from the red snow alga Chlamydomonas nivalis collected in Austrian Alps, Slovak High Tatra Mountains and Bulgarian Pirin. We observed a striking difference in the composition of astaxanthin optical isomers in C. nivalis collected in geographically distinct regions. Furthermore, algae from the Pirin Mountains differed in the dominance of astaxanthin diglucoside diesters, suggesting an alternative strategy to enhance cell viability at low temperatures. PMID:23398889

  9. Determination of astaxanthin stereoisomers and colour attributes in flesh of rainbow trout (Oncorhynchuss mykiss) as a tool to distinguish dietary pigmentation source

    OpenAIRE

    Moretti, Vittorio Maria; Mentasti, Tiziana; Bellagamba, Federica; Luzzana, Umberto; Caprino, Fabio; Turchini, Giovanni; Giani, Ivan; Valfrè, Franco

    2006-01-01

    Abstract The presence of carotenoids in animal reflects their sources along with the food chain. Astaxanthin, the main carotenoid used for salmonid pigmentation, is usually included in the feed as a synthetic product. However, other dietary sources of astaxanthin such as shrimp or krill wastes, algae meal or yeasts are also available on the market. Astaxanthin possesses two identical asymmetric atoms at C-3 and C-3? making possible three optical isomers with all-trans configuration...

  10. Influence of Oxygen and Glucose on Primary Metabolism and Astaxanthin Production by Phaffia rhodozyma in Batch and Fed-Batch Cultures: Kinetic and Stoichiometric Analysis

    OpenAIRE

    Yamane, Y.; Higashida, K.; Nakashimada, Y.; Kakizono, T.; Nishio, N.

    1997-01-01

    The influence of the oxygen and glucose supply on primary metabolism (fermentation, respiration, and anabolism) and astaxanthin production in the yeast Phaffia rhodozyma was investigated. When P. rhodozyma grew under fermentative conditions with limited oxygen or high concentrations of glucose, the astaxanthin production rate decreased remarkably. On the other hand, when the yeast grew under aerobic conditions, the astaxanthin production rate increased with increasing oxygen uptake. A kinetic...

  11. Anti-Oxidative, Anti-Tumor-Promoting, and Anti-Carcinogensis Activities of Nitroastaxanthin and Nitrolutein, the Reaction Products of Astaxanthin and Lutein with Peroxynitrite

    OpenAIRE

    Hideo Etoh; Hideaki Kato; Takashi Maoka; Harukuni Tokuda; Nobutaka Suzuki

    2012-01-01

    Astaxanthin captured peroxynitrite to form nitroastaxanthins. 15-Nitroastaxanthin was a major reaction product of astaxanthin with peroxynitrite. Here, the anti-oxidative, anti-tumor-promoting, and anti-carcinogensis activities of 15-nitroastaxanthin were investigated. In addition to astaxanthin, 15-nitroastaxanthin showed excellent singlet oxygen quenching activity. Furthermore, 15-nitroastaxanthin showed inhibitory effects of in vitro Epstein-Barr virus early antigen ac...

  12. Astaxanthin down-regulates Rad51 expression via inactivation of AKT kinase to enhance mitomycin C-induced cytotoxicity in human non-small cell lung cancer cells.

    Science.gov (United States)

    Ko, Jen-Chung; Chen, Jyh-Cheng; Wang, Tai-Jing; Zheng, Hao-Yu; Chen, Wen-Ching; Chang, Po-Yuan; Lin, Yun-Wei

    2016-04-01

    Astaxanthin has been demonstrated to exhibit a wide range of beneficial effects, including anti-inflammatory and anti-cancer properties. However, the molecular mechanism of astaxanthin-induced cytotoxicity in non-small cell lung cancer (NSCLC) cells has not been identified. Rad51 plays a central role in homologous recombination, and studies show that chemo-resistant carcinomas exhibit high levels of Rad51 expression. In this study, astaxanthin treatment inhibited cell viability and proliferation of two NSCLC cells, A549 and H1703. Astaxanthin treatment (2.5-20μM) decreased Rad51 expression and phospho-AKT(Ser473) protein level in a time and dose-dependent manner. Furthermore, expression of constitutively active AKT (AKT-CA) vector rescued the decreased Rad51 mRNA and protein levels in astaxanthin-treated NSCLC cells. Combined treatment with phosphatidylinositol 3-kinase (PI3K) inhibitors (LY294002 or wortmannin) further decreased the Rad51 expression in astaxanthin-exposed A549 and H1703 cells. Knockdown of Rad51 expression by transfection with si-Rad51 RNA or cotreatment with LY294002 further enhanced the cytotoxicity and cell growth inhibition of astaxanthin. Additionally, mitomycin C (MMC) as an anti-tumor antibiotic is widely used in clinical NSCLC chemotherapy. Combination of MMC and astaxanthin synergistically resulted in cytotoxicity and cell growth inhibition in NSCLC cells, accompanied with reduced phospho-AKT(Ser473) level and Rad51 expression. Overexpression of AKT-CA or Flag-tagged Rad51 reversed the astaxanthin and MMC-induced synergistic cytotoxicity. In contrast, pretreatment with LY294002 further decreased the cell viability in astaxanthin and MMC co-treated cells. In conclusion, astaxanthin enhances MMC-induced cytotoxicity by decreasing Rad51 expression and AKT activation. These findings may provide rationale to combine astaxanthin with MMC for the treatment of NSCLC. PMID:26921637

  13. Effects of homogenization process parameters on physicochemical properties of astaxanthin nanodispersions prepared using a solvent-diffusion technique

    OpenAIRE

    Anarjan, Navideh; Jafarizadeh-Malmiri, Hoda; Nehdi, Imededdine Arbi; Sbihi, Hassen Mohamed; Al-Resayes, Saud Ibrahim; Tan, Chin Ping

    2015-01-01

    Nanodispersion systems allow incorporation of lipophilic bioactives, such as astaxanthin (a fat soluble carotenoid) into aqueous systems, which can improve their solubility, bioavailability, and stability, and widen their uses in water-based pharmaceutical and food products. In this study, response surface methodology was used to investigate the influences of homogenization time (0.5–20 minutes) and speed (1,000–9,000 rpm) in the formation of astaxanthin nanodispersions via the solvent-diffus...

  14. Effects of astaxanthin-rich Haematococcus pluvialis extract on cognitive function: a randomised, double-blind, placebo-controlled study

    OpenAIRE

    Katagiri, Mikiyuki; Satoh, Akira; Tsuji, Shinji; Shirasawa, Takuji

    2012-01-01

    In this study we tried to confirm the effect of an astaxanthin-rich Haematococcus pluvialis extract on cognitive function in 96 subjects by a randomised double-blind placebo-controlled study. Healthy middle-aged and elderly subjects who complained of age-related forgetfulness were recruited. Ninety-six subjects were selected from the initial screen, and ingested a capsule containing astaxanthin-rich Haematococcus pluvialis extract, or a placebo capsule for 12 weeks. Somatometry, haematology, ...

  15. Neuroprotective effect of astaxanthin against rat retinal ganglion cell death under various stresses that induce apoptosis and necrosis

    OpenAIRE

    Yamagishi, Reiko; Aihara, Makoto

    2014-01-01

    Purpose Astaxanthin is a type of carotenoid known to have strong antioxidant effects. The purpose of this study was to investigate whether astaxanthin confers a neuroprotective effect against glutamate stress, oxidative stress, and hypoxia-induced apoptotic or necrotic cell death in primary cultures of rat retinal ganglion cells (RGCs). Methods Purified rat RGCs were exposed to three kinds of stressors induced by 25 μM glutamate for 72 h, B27 medium without an antioxidant for 4 h, and a reduc...

  16. The Effects of Salinity, Phosphate Deprivation and Eosin on Growth and Astaxanthin Production in Unicellular Green Alga, Haematococcus Pluvialis

    OpenAIRE

    M. Mahdiyeh; S. Farrahi-Ashtiani; I. Nahvi

    2002-01-01

    In order to increase ketocarotenoid astaxanthin production by Haematococcus pluvialis, the effects of salinity, phosphate deprivation and eosin on growth and astaxanhin production were examined. The experiments were carried out in the growth chamber at 20oC under sterile conditions. The results showed that under salinity, phosphate deprivation and eosin supply, encystment was induced, and at the same time, astaxanthin formation and dry weight increased. Furthermore, by adding histidine to cul...

  17. Lipid profile and glucose changes after supplementation with astaxanthin: a systematic review and meta-analysis of randomized controlled trials

    OpenAIRE

    Ursoniu, Sorin; Sahebkar, Amirhossein; Serban, Maria-Corina; Banach, Maciej

    2015-01-01

    Introduction Many studies have shown that oral supplementation with astaxanthin may be a novel potential treatment for inflammation and oxidative stress in cardiovascular diseases, but evidence of the effects on lipid profile and glucose is still inconclusive. Therefore, we performed a meta-analysis to evaluate the efficacy of astaxanthin supplementation on plasma lipid and glucose concentrations. Material and methods The search included PubMed, Cochrane Library, Scopus, and EMBASE (up to Nov...

  18. The synthesis of astaxanthin esters,independent of the formation of cysts,highly correlates with the synthesis of fatty acids in Haematococcus pluvialis

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The compositions and contents of astaxanthin esters and fatty acids in four types of Haematococcus pluvialis cells were studied by HPLC and GC-MS. Results showed that the synthesis and accumulation of astaxanthin was independent of the formation of cysts, but was highly correlated with the synthesis and accumulation of fatty acids, though it is an well known phenomenon that the accumulation of astaxanthin is usually accompanied by the formation of cyst. The red cysts contain more than 30% of fatty acids, with 81% of the unsaturated fatty acids. Taken together, besides a resource of astaxanthin, H. pluvialis would be a good resource of valuable fatty acids.

  19. Anti-Oxidative, Anti-Tumor-Promoting, and Anti-Carcinogensis Activities of Nitroastaxanthin and Nitrolutein, the Reaction Products of Astaxanthin and Lutein with Peroxynitrite

    Directory of Open Access Journals (Sweden)

    Hideo Etoh

    2012-06-01

    Full Text Available Astaxanthin captured peroxynitrite to form nitroastaxanthins. 15-Nitroastaxanthin was a major reaction product of astaxanthin with peroxynitrite. Here, the anti-oxidative, anti-tumor-promoting, and anti-carcinogensis activities of 15-nitroastaxanthin were investigated. In addition to astaxanthin, 15-nitroastaxanthin showed excellent singlet oxygen quenching activity. Furthermore, 15-nitroastaxanthin showed inhibitory effects of in vitro Epstein-Barr virus early antigen activation and two-stage carcinogensis on mouse skin papillomas. These activities were slightly higher than those of astaxanthin. Similar results were obtained for the 15-nitrolutein, a major reaction product of lutein with peroxynitrite.

  20. The antioxidant effect of astaxanthin is higher in young mice than aged: a region specific study on brain.

    Science.gov (United States)

    Al-Amin, Md Mamun; Akhter, Samiha; Hasan, Ahmed Tasdid; Alam, Tanzir; Nageeb Hasan, S M; Saifullah, A R M; Shohel, Mohammad

    2015-10-01

    Astaxanthin is a potential antioxidant which shows neuroprotective property. We aimed to investigate the age-dependent and region-specific antioxidant effects of astaxanthin in mice brain. Animals were divided into 4 groups; treatment young (3 months, n = 6) (AY), treatment old (16 months, n = 6) (AO), placebo young (3 months, n = 6) (PY) and placebo old (16 months, n = 6) (PO) groups. Treatment group was given astaxanthin (2 mg/kg/day, body weight), and placebo group was given 100 μl of 0.9% normal saline orally to the healthy Swiss albino mice for 4 weeks. The level of non-enzymatic oxidative markers namely malondialdehyde (MDA); nitric oxide (NO); advanced protein oxidation product (APOP); glutathione (GSH) and the activity of enzymatic antioxidants i.e.; catalase (CAT) and superoxide dismutase (SOD) were determined from the isolated brain regions. Treatment with astaxanthin significantly (p Astaxanthin markedly (p astaxanthin is age-dependent, higher in young in compared to the aged brain. PMID:26116165

  1. Dietary Carotenoids Regulate Astaxanthin Content of Copepods and Modulate Their Susceptibility to UV Light and Copper Toxicity

    Directory of Open Access Journals (Sweden)

    Kevin R. Carman

    2012-04-01

    Full Text Available High irradiation and the presence of xenobiotics favor the formation of reactive oxygen species in marine environments. Organisms have developed antioxidant defenses, including the accumulation of carotenoids that must be obtained from the diet. Astaxanthin is the main carotenoid in marine crustaceans where, among other functions, it scavenges free radicals thus protecting cell compounds against oxidation. Four diets with different carotenoid composition were used to culture the meiobenthic copepod Amphiascoides atopus to assess how its astaxanthin content modulates the response to prooxidant stressors. A. atopus had the highest astaxanthin content when the carotenoid was supplied as astaxanthin esters (i.e., Haematococcus meal. Exposure to short wavelength UV light elicited a 77% to 92% decrease of the astaxanthin content of the copepod depending on the culture diet. The LC50 values of A. atopus exposed to copper were directly related to the initial astaxanthin content. The accumulation of carotenoids may ascribe competitive advantages to certain species in areas subjected to pollution events by attenuating the detrimental effects of metals on survival, and possibly development and fecundity. Conversely, the loss of certain dietary items rich in carotenoids may be responsible for the amplification of the effects of metal exposure in consumers.

  2. Metabolic model for diversity-generating biosynthesis.

    Science.gov (United States)

    Tianero, Ma Diarey; Pierce, Elizabeth; Raghuraman, Shrinivasan; Sardar, Debosmita; McIntosh, John A; Heemstra, John R; Schonrock, Zachary; Covington, Brett C; Maschek, J Alan; Cox, James E; Bachmann, Brian O; Olivera, Baldomero M; Ruffner, Duane E; Schmidt, Eric W

    2016-02-16

    A conventional metabolic pathway leads to a specific product. In stark contrast, there are diversity-generating metabolic pathways that naturally produce different chemicals, sometimes of great diversity. We demonstrate that for one such pathway, tru, each ensuing metabolic step is slower, in parallel with the increasing potential chemical divergence generated as the pathway proceeds. Intermediates are long lived and accumulate progressively, in contrast with conventional metabolic pathways, in which the first step is rate-limiting and metabolic intermediates are short-lived. Understanding these fundamental differences enables several different practical applications, such as combinatorial biosynthesis, some of which we demonstrate here. We propose that these principles may provide a unifying framework underlying diversity-generating metabolism in many different biosynthetic pathways. PMID:26831074

  3. Astaxanthin Attenuates Early Acute Kidney Injury Following Severe Burns in Rats by Ameliorating Oxidative Stress and Mitochondrial-Related Apoptosis

    Directory of Open Access Journals (Sweden)

    Song-Xue Guo

    2015-04-01

    Full Text Available Early acute kidney injury (AKI is a devastating complication in critical burn patients, and it is associated with severe morbidity and mortality. The mechanism of AKI is multifactorial. Astaxanthin (ATX is a natural compound that is widely distributed in marine organisms; it is a strong antioxidant and exhibits other biological effects that have been well studied in various traumatic injuries and diseases. Hence, we attempted to explore the potential protection of ATX against early post burn AKI and its possible mechanisms of action. The classic severe burn rat model was utilized for the histological and biochemical assessments of the therapeutic value and mechanisms of action of ATX. Upon ATX treatment, renal tubular injury and the levels of serum creatinine and neutrophil gelatinase-associated lipocalin were improved. Furthermore, relief of oxidative stress and tubular apoptosis in rat kidneys post burn was also observed. Additionally, ATX administration increased Akt and Bad phosphorylation and further down-regulated the expression of other downstream pro-apoptotic proteins (cytochrome c and caspase-3/9; these effects were reversed by the PI3K inhibitor LY294002. Moreover, the protective effect of ATX presents a dose-dependent enhancement. The data above suggested that ATX protects against early AKI following severe burns in rats, which was attributed to its ability to ameliorate oxidative stress and inhibit apoptosis by modulating the mitochondrial-apoptotic pathway, regarded as the Akt/Bad/Caspases signalling cascade.

  4. Carotenoid Metabolism: Biosynthesis, Regulation,and Beyond

    Institute of Scientific and Technical Information of China (English)

    Shan Lu; Li Li

    2008-01-01

    Carotenoids are Indispensable to plants and play a critical role in human nutrition and health. Significant progress has been made in our understanding of carotenoid metabolism in plants. The biosynthetic pathway has been extensively studied.Nearly all the genes encoding the biosynthetic enzymes have been isolated and characterized from various organisms. In recent years, there is an increasing body of work on the signaling pathways and plastid development, which might provide global control of carotenoid biosynthesis and accumulation. Herein, we will highlight recent progress on the biosynthesis,regulation, and metabolic engineering of carotenoids in plants, as well as the future research towards elucidating the regulatory mechanisms and metabolic network that control carotenoid metabolism.

  5. PLANT VOLATILES. Biosynthesis of monoterpene scent compounds in roses.

    Science.gov (United States)

    Magnard, Jean-Louis; Roccia, Aymeric; Caissard, Jean-Claude; Vergne, Philippe; Sun, Pulu; Hecquet, Romain; Dubois, Annick; Hibrand-Saint Oyant, Laurence; Jullien, Frédéric; Nicolè, Florence; Raymond, Olivier; Huguet, Stéphanie; Baltenweck, Raymonde; Meyer, Sophie; Claudel, Patricia; Jeauffre, Julien; Rohmer, Michel; Foucher, Fabrice; Hugueney, Philippe; Bendahmane, Mohammed; Baudino, Sylvie

    2015-07-01

    The scent of roses (Rosa x hybrida) is composed of hundreds of volatile molecules. Monoterpenes represent up to 70% percent of the scent content in some cultivars, such as the Papa Meilland rose. Monoterpene biosynthesis in plants relies on plastid-localized terpene synthases. Combining transcriptomic and genetic approaches, we show that the Nudix hydrolase RhNUDX1, localized in the cytoplasm, is part of a pathway for the biosynthesis of free monoterpene alcohols that contribute to fragrance in roses. The RhNUDX1 protein shows geranyl diphosphate diphosphohydrolase activity in vitro and supports geraniol biosynthesis in planta. PMID:26138978

  6. The tRNA-Dependent Biosynthesis of Modified Cyclic Dipeptides

    OpenAIRE

    Giessen, Tobias W.; Mohamed A. Marahiel

    2014-01-01

    In recent years it has become apparent that aminoacyl-tRNAs are not only crucial components involved in protein biosynthesis, but are also used as substrates and amino acid donors in a variety of other important cellular processes, ranging from bacterial cell wall biosynthesis and lipid modification to protein turnover and secondary metabolite assembly. In this review, we focus on tRNA-dependent biosynthetic pathways that generate modified cyclic dipeptides (CDPs). The essential peptide bond...

  7. Evolution of the Kdo2-lipid A biosynthesis in bacteria

    OpenAIRE

    Moriyama Hideaki; Pardy Rosevelt L; Opiyo Stephen O; Moriyama Etsuko N

    2010-01-01

    Abstract Background Lipid A is the highly immunoreactive endotoxic center of lipopolysaccharide (LPS). It anchors the LPS into the outer membrane of most Gram-negative bacteria. Lipid A can be recognized by animal cells, triggers defense-related responses, and causes Gram-negative sepsis. The biosynthesis of Kdo2-lipid A, the LPS substructure, involves with nine enzymatic steps. Results In order to elucidate the evolutionary pathway of Kdo2-lipid A biosynthesis, we examined the distribution o...

  8. On the bathochromic shift of the absorption by astaxanthin in crustacyanin: a quantum chemical study

    Science.gov (United States)

    Durbeej, Bo; Eriksson, Leif A.

    2003-06-01

    The structural origin of the bathochromic shift assumed by the electronic absorption spectrum of protein-bound astaxanthin, the carotenoid that upon binding to crustacyanin is responsible for the blue colouration of lobster shell, is investigated by means of quantum chemical methods. The calculations suggest that the bathochromic shift is largely due to one of the astaxanthin C4 keto groups being hydrogen-bonded to a histidine residue of the surrounding protein, and that the effect of this histidine is directly dependent on its protonation state. Out of the different methodologies (CIS, TD-DFT, and ZINDO/S) employed to calculate wavelengths of maximum absorption, the best agreement with experimental data is obtained using the semiempirical ZINDO/S method.

  9. Astaxanthin preparation by lipase-catalyzed hydrolysis of its esters from Haematococcus pluvialis algal extracts.

    Science.gov (United States)

    Zhao, Yingying; Guan, Feifei; Wang, Guili; Miao, Lili; Ding, Jing; Guan, Guohua; Li, Ying; Hui, Bodi

    2011-05-01

    Five of 8 fungal lipases screened were found to effectively hydrolyze astaxanthin esters from Haematococcus pluvialis algal cell extracts. Among these, an alkaline lipase from Penicillium cyclopium, expressed in Pichia pastoris, had the highest enzymolysis efficiency. Tween80 was shown to be an effective emulsifier in this lipase hydrolysis system for the 1st time. A series of experiments were performed to find optimal conditions for hydrolysis (pH, temperature, reaction time, lipase dosage). In the optimal reaction system, Tween80 and H. pluvialis extracts (mass ratio 1:1) were emulsified and added to the above lipase at a dosage of 4.6 U/μg (relative to total carotenoids), in phosphate buffer (0.1 M, pH 7.0), and incubated at 28 °C for 7 h, with agitation at 180 rpm. The free astaxanthin recovery ratio under these conditions was 63.2%. PMID:22417348

  10. Astaxanthin alleviates oxidative stress insults-related derangements in human vascular endothelial cells exposed to glucose fluctuations.

    Science.gov (United States)

    Abdelzaher, Lobna A; Imaizumi, Takahiro; Suzuki, Tokiko; Tomita, Kengo; Takashina, Michinori; Hattori, Yuichi

    2016-04-01

    Glycemic fluctuations may play a critical role in the pathogenesis of diabetic complications, such as cardiovascular disease. We investigated whether the oxycarotenoid astaxanthin can reduce the detrimental effects of fluctuating glucose on vascular endothelial cells. Human umbilical venous endothelial cells were incubated for 3days in media containing 5.5mM glucose, 22mM glucose, or 5.5mM glucose alternating with 22mM glucose in the absence or presence of astaxanthin or N-acetyl-L-cysteine (NAC). Constant high glucose increased reactive oxygen species (ROS) generation, but such an effect was more pronounced in fluctuating glucose. This was associated with up-regulated p22(phox) expression and down-regulated peroxisome proliferator activated receptor-γ coactivator (PGC-1α) expression. Astaxanthin inhibited ROS generation, p22(phox) up-regulation, and PGC-1α down-regulation by the stimuli of glucose fluctuation. Fluctuating glucose, but not constant high glucose, significantly decreased the endothelial nitric oxide synthase (eNOS) phosphorylation level at Ser-1177 without affecting total eNOS expression, which was prevented by astaxanthin as well as by the anti-oxidant NAC. Transferase-mediated dUTP nick end labeling (TUNEL) showed increased cell apoptosis in fluctuating glucose. Glucose fluctuation also resulted in up-regulating gene expression of pro-inflammatory mediators, interleukin-6 and intercellular adhesion molecule-1. These adverse changes were subdued by astaxanthin. The phosphorylation levels of c-Jun N-terminal kinase (JNK) and p38 were significantly increased by glucose fluctuations, and astaxanthin significantly inhibited the increase in JNK and p38 phosphorylation. Taken together, our results suggest that astaxanthin can protect vascular endothelial cells against glucose fluctuation by reducing ROS generation. PMID:26924495

  11. Efficiency of Lignin Biosynthesis: a Quantitative Analysis

    OpenAIRE

    Amthor, Jeffrey S.

    2003-01-01

    Lignin is derived mainly from three alcohol monomers: p‐coumaryl alcohol, coniferyl alcohol and sinapyl alcohol. Biochemical reactions probably responsible for synthesizing these three monomers from sucrose, and then polymerizing the monomers into lignin, were analysed to estimate the amount of sucrose required to produce a unit of lignin. Included in the calculations were amounts of respiration required to provide NADPH (from NADP+) and ATP (from ADP) for lignin biosynthesis. Two pathways in...

  12. Oleic acid biosynthesis in cyanobacteria

    International Nuclear Information System (INIS)

    The biosynthesis of fatty acids in cyanobacteria is very similar to the well characterized system found in green plants. However, the initial desaturation of stearic acid in cyanobacteria appears to represent a significant departure from plant systems in which stearoyl-ACP is the exclusive substrate for desaturation. In Anabaena variabilis, the substrate appears to be monoglucosyldiacylglycerol, a lipid not found in plants. The authors examined five different cyanobacteria to determine if the pathway in A. variabilis was generally present in other cyanobacteria. The cyanobacteria studied were A. variabilis, Chlorogloeopsis sp., Schizothrix calcicola, Anacystis marina, and Anacystis nidulans. Each were grown in liquid culture, harvested, and examined for stearoyl-ACP desaturase activity or incubated with 14CO2. None of the cyanobacteria contained any stearoyl-ACP desaturase activity in whole homogenates or 105,000g supernatants. All were capable of incorporating 14CO2 into monoglucosyldiacylglycerol and results from incubations of 20 min, 1 hr, 1 hr + 10 hr chase were consistent with monoglucosyldiacylglycerol serving as precursor for monogalctosyldiacylglycerol. Thus, initial evidence is consistent with oleic acid biosynthesis occurring by desaturation of stearoyl-monoglucosyldiacylglycerol in all cyanobacteria

  13. Effects of Selected Polysorbate and Sucrose Ester Emulsifiers on the Physicochemical Properties of Astaxanthin Nanodispersions

    OpenAIRE

    Navideh Anarjan; Chin Ping Tan

    2013-01-01

    The effects of selected nonionic emulsifiers on the physicochemical characteristics of astaxanthin nanodispersions produced by an emulsification/evaporation technique were studied. The emulsifiers used were polysorbates (Polysorbate 20, Polysorbate 40, Polysorbate 60 and Polysorbate 80) and sucrose esters of fatty acids (sucrose laurate, palmitate, stearate and oleate). The mean particle diameters of the nanodispersions ranged from 70 nm to 150 nm, depending on the emulsifier used. In the pre...

  14. Mussel processing wastewater: a low-cost substrate for the production of astaxanthin by Xanthophyllomyces dendrorhous

    OpenAIRE

    Amado, Isabel Rodríguez; Vázquez, José Antonio

    2015-01-01

    Background The use of astaxanthin in different industries such as the chemical, pharmaceutical, food, animal feed and cosmetic has been receiving increasing attention in recent years. Natural supplies of the pigment include crustacean by-products, algal, and microbial cultivation, being the yeast Xanthophyllomyces dendrorhous together with the alga Haematococcus pluvialis the most promising microorganisms for this bioproduction. Different vegetable by-products of the food industry have been e...

  15. Anti-inflammatory effects of astaxanthin in the human gingival keratinocyte line NDUSD-1

    OpenAIRE

    Miyachi, Masashiro; Matsuno, Tomonori; Asano, Kazunari; Mataga, Izumi

    2015-01-01

    Oral lichen planus is a chronic inflammatory disease that affects the mucous membrane of the oral cavity and can contribute to the development of other diseases. Inflammation in oral lichen planus is a T-cell-mediated autoimmune disease that acts through cytotoxic CD8+ T cells to trigger apoptosis of keratinocytes. However, the specific cause of oral lichen planus remains unknown and no effective medical treatment has yet been established. Astaxanthin is a carotenoid pigment with capacity for...

  16. First step of glycosylphosphatidylinositol (GPI) biosynthesis cross-talks with ergosterol biosynthesis and Ras signaling in Candida albicans.

    Science.gov (United States)

    Yadav, Bhawna; Bhatnagar, Shilpi; Ahmad, Mohammad Faiz; Jain, Priyanka; Pratyusha, Vavilala A; Kumar, Pravin; Komath, Sneha Sudha

    2014-02-01

    Candida albicans is a leading cause of fungal infections worldwide. It has several glycosylphosphatidylinositol (GPI)-anchored virulence factors. Inhibiting GPI biosynthesis attenuates its virulence. Building on our previous work, we explore the interaction of GPI biosynthesis in C. albicans with ergosterol biosynthesis and hyphal morphogenesis. This study is also the first report of transcriptional co-regulation existing between two subunits of the multisubunit enzyme complex, GPI-N-acetylglucosaminyltransferase (GPI-GnT), involved in the first step of GPI anchor biosynthesis in eukaryotes. Using mutational analysis, we show that the accessory subunits, GPI2 and GPI19, of GPI-GnT exhibit opposite effects on ergosterol biosynthesis and Ras signaling (which determines hyphal morphogenesis). This is because the two subunits negatively regulate one another; GPI19 mutants show up-regulation of GPI2, whereas GPI2 mutants show up-regulation of GPI19. Two different models were examined as follows. First, the two GPI-GnT subunits independently interact with ergosterol biosynthesis and Ras signaling. Second, the two subunits mutually regulate one another and thereby regulate sterol levels and Ras signaling. Analysis of double mutants of these subunits indicates that GPI19 controls ergosterol biosynthesis through ERG11 levels, whereas GPI2 determines the filamentation by cross-talk with Ras1 signaling. Taken together, this suggests that the first step of GPI biosynthesis talks to and regulates two very important pathways in C. albicans. This could have implications for designing new antifungal strategies. PMID:24356967

  17. Metabolomic and network analysis of astaxanthin-producing Haematococcus pluvialis under various stress conditions.

    Science.gov (United States)

    Su, Yingxue; Wang, Jiangxin; Shi, Mengliang; Niu, Xiangfeng; Yu, Xinheng; Gao, Lianju; Zhang, Xiaoqing; Chen, Lei; Zhang, Weiwen

    2014-10-01

    Various combinations of acetate (Ac), Fe(2+) and high light (HL) stress conditions were evaluated to maximize astaxanthin accumulation and biomass production in Haematococcus pluvialis, and then GC-MS and LC-MS based metabolomics were applied to determine molecular mechanisms responsible for enhancing astaxanthin accumulation under the stress conditions. With the optimized analytical protocols, the GC-MS and LC-MS analyses allowed identification of 93 stable and 24 unstable intracellular metabolites from H. pluvialis, respectively. In addition, a metabolic network was constructed based on GC-MS metabolomic datasets using a weighted correlation network analysis (WGCNA) approach. The network analysis uncovered 2, 1 and 1 distinguished metabolic modules highly associated with HL, Fe(2+) & HL, and Ac & Fe(2+) & HL conditions, respectively. Finally, LC-MS analysis found that AKG, Glu and R5P may be metabolites associated with the Fe(2+) & HL condition. The study provided the first metabolomic view of cell growth and astaxanthin accumulation in H. pluvialis. PMID:25164345

  18. Quantitative detection of astaxanthin and cantaxanthin in Atlantic salmon by resonance Raman spectroscopy

    Science.gov (United States)

    Ermakov, Igor V.; Ermakova, Maia R.; Gellermann, Werner

    2006-02-01

    Two major carotenoids species found in salmonids muscle tissues are astaxanthin and cantaxanthin. They are taken up from fish food and are responsible for the attractive red-orange color of salmon filet. Since carotenoids are powerful antioxidants and biomarkers of nutrient consumption, they are thought to indicate fish health and resistance to diseases in fish farm environments. Therefore, a rapid, accurate, quantitative optical technique for measuring carotenoid content in salmon tissues is of economic interest. We demonstrate the possibility of using fast, selective, quantitative detection of astaxanthin and cantaxanthin in salmon muscle tissues, employing resonance Raman spectroscopy. Analyzing strong Raman signals originating from the carbon-carbon double bond stretch vibrations of the carotenoid molecules under blue laser excitation, we are able to characterize quantitatively the concentrations of carotenoids in salmon muscle tissue. To validate the technique, we compared Raman data with absorption measurements of carotenoid extracts in acetone. A close correspondence was observed in absorption spectra for tissue extract in acetone and a pure astaxanthin solution. Raman results show a linear dependence between Raman and absorption data. The proposed technique holds promise as a method of rapid screening of carotenoid levels in fish muscle tissues and may be attractive for the fish farm industry to assess the dietary status of salmon, risk for infective diseases, and product quality control.

  19. Fatty acids attached to all-trans-astaxanthin alter its cis-trans equilibrium, and consequently its stability, upon light-accelerated autoxidation.

    Science.gov (United States)

    de Bruijn, Wouter J C; Weesepoel, Yannick; Vincken, Jean-Paul; Gruppen, Harry

    2016-03-01

    Fatty acid esterification, common in naturally occurring astaxanthin, has been suggested to influence both colour stability and degradation of all-trans-astaxanthin. Therefore, astaxanthin stability was studied as influenced by monoesterification and diesterification with palmitate. Increased esterification decelerated degradation of all-trans-astaxanthin (RP-UHPLC-PDA), whereas, it had no influence on colour loss over time (spectrophotometry). This difference might be explained by the observation that palmitate esterification influenced the cis-trans equilibrium. Free astaxanthin produced larger amounts of 9-cis isomer whereas monopalmitate esterification resulted in increased 13-cis isomerization. The molar ratios of 9-cis:13-cis after 60min were 1:1.7 (free), 1:4.8 (monopalmitate) and 1:2.6 (dipalmitate). The formation of 9-cis astaxanthin, with its higher molar extinction coefficient than that of all-trans-astaxanthin, might compensate for colour loss induced by conjugated double bond cleavage. As such, it was concluded that spectrophotometry is not an accurate measure of the degradation of the all-trans-astaxanthin molecule. PMID:26471660

  20. Influence of high-pressure homogenization, ultrasonication, and supercritical fluid on free astaxanthin extraction from β-glucanase-treated Phaffia rhodozyma cells.

    Science.gov (United States)

    Hasan, Mojeer; Azhar, Mohd; Nangia, Hina; Bhatt, Prakash Chandra; Panda, Bibhu Prasad

    2016-01-01

    In this study astaxanthin production by Phaffia rhodozyma was enhanced by chemical mutation using ethyl methane sulfonate. The mutant produces a higher amount of astaxanthin than the wild yeast strain. In comparison to supercritical fluid technique, high-pressure homogenization is better for extracting astaxanthin from yeast cells. Ultrasonication of dimethyl sulfoxide, hexane, and acetone-treated cells yielded less astaxanthin than β-glucanase enzyme-treated cells. The combination of ultrasonication with β-glucanase enzyme is found to be the most efficient method of extraction among all the tested physical and chemical extraction methods. It gives a maximum yield of 435.71 ± 6.55 µg free astaxanthin per gram of yeast cell mass. PMID:25569162

  1. Terpenoid Indole Alkaloids Biosynthesis and Metabolic Engineering in Catharanthus roseus

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Catharanthus roseus L. (Madagascar periwinkle) biosynthesizes a diverse array of secondary metabolites including anticancer dimeric alkaloids (vinblastine and vincristine) and antihypertensive alkaloids (ajmalicine and serpentine). The multi-step terpenoid indole alkaloids (TIAs) biosynthetic pathway in C. roseus is complex and is under strict molecular regulation. Many enzymes and genes involved in the TIAs biosynthesis have been studied in recent decades. Moreover,some regulatory proteins were found recently to control the production of TIAs in C. roseus. Based on mastering the rough scheme of the pathway and cloning the related genes, metabolic engineering of TIAs biosynthesis has been studied in C.roseus aiming at increasing the desired secondary metabolites in the past few years. The present article summarizes recent advances in isolation and characterization of TIAs biosynthesis genes and transcriptional regulators involved in the second metabolic control in C. roseus. Metabolic engineering applications in TIAs pathway via overexpression of these genes and regulators in C. roseus are also discussed.

  2. Effects of dietary supplementation with astaxanthin and β-carotene on the semen quality of goldfish (Carassius auratus).

    Science.gov (United States)

    Tizkar, B; Kazemi, R; Alipour, A; Seidavi, A; Naseralavi, G; Ponce-Palafox, J T

    2015-10-15

    This study was conducted to investigate the effects of two carotenoids (astaxanthin and β-carotene) on the sperm quality of goldfish Carassius auratus (Linnaeus, 1758). For this purpose, six diets containing concentrations of 50, 100, and 150 mg/kg of synthetic astaxanthin and β-carotene were added to a basic carp diet. One group of fish was also fed with a control diet (no added carotenoids). Osmolality, spermatocrit value, and sperm concentration significantly increased in the treatment supplemented with 150 mg/kg of astaxanthin (296.6 ± 1.1 mOsm/kg; 29.2 ± 0.6%; 17.2 ± 0.4 × 10(9) cells/mL, respectively) and β-carotene (295.2 ± 2.1 mOsm/kg; 32.5 ± 1.6%; 17.9 ± 0.5 × 10(9) cells/mL, respectively). The highest concentration of astaxanthin (10.4 ± 1.4 mg/kg) was recorded in the treatment of A150 (P astaxanthin improves osmolality, motility, fertilization rate, and sperm concentration. PMID:26166170

  3. Conversion of β-carotene into astaxanthin: Two separate enzymes or a bifunctional hydroxylase-ketolase protein?

    Directory of Open Access Journals (Sweden)

    Gudiña Eduardo

    2008-02-01

    Full Text Available Abstract Astaxanthin is a xanthophyll of great interest in animal nutrition and human health. The market prospect in the nutraceutics industries for this health-protective molecule is very promising. Astaxanthin is synthesized by several bacteria, algae and plants from β-carotene by the sequential action of two enzymes: a β-carotene, 3,3'-hydroxylase that introduces an hydroxyl group at the 3 (and 3' positions of each of the two β-ionone rings of β-carotene, and a β-carotene ketolase that introduces keto groups at carbons 4 and 4' of the β-ionone rings. Astaxanthin is also produced by the yeast-like basidiomycete Xanthophyllomyces dendrorhous. A gene crtS involved in the conversion of β-carotene to astaxanthin has been cloned simultaneously by two research groups. Complementation studies of X. dendrorhous mutants and expression analysis in Mucor circinelloides reveals that the CrtS enzyme is a β-carotene hydroxylase of the P-450 monooxygenase family that converts β-carotene to the hydroxylated derivatives β-cryptoxanthin and zeaxanthin, but it does not form astaxanthin or the ketolated intermediates in this fungus. A bifunctional β-carotene hydroxylase-ketolase activity has been proposed for the CrtS protein. The evidence for and against this hypothesis is analyzed in detail in this review.

  4. Astaxanthin, a Carotenoid, Stimulates Immune Responses by Enhancing IFN-γ and IL-2 Secretion in Primary Cultured Lymphocytes in Vitro and ex Vivo.

    Science.gov (United States)

    Lin, Kuan-Hung; Lin, Kao-Chang; Lu, Wan-Jung; Thomas, Philip-Aloysius; Jayakumar, Thanasekaran; Sheu, Joen-Rong

    2016-01-01

    Astaxanthin, a potent antioxidant carotenoid, plays a major role in modulating the immune response. In this study, we examined the immunomodulatory effects of astaxanthin on cytokine production in primary cultured lymphocytes both in vitro and ex vivo. Direct administration of astaxanthin (70-300 nM) did not produce cytotoxicity in lipopolysaccharide (LPS, 100 µg/ mL)- or concanavalin A (Con A, 10 µg/ mL)-activated lymphocytes, whereas astaxanthin alone at 300 nM induced proliferation of splenic lymphocytes (p astaxanthin, alone or with Con A, had no apparent effect on interferon (INF-γ) and interleukin (IL-2) production in primary cultured lymphocytes, it enhanced LPS-induced INF-γ production. In an ex vivo experiment, oral administration of astaxanthin (0.28, 1.4 and 7 mg/kg/day) for 14 days did not cause alterations in the body or spleen weights of mice and also was not toxic to lymphocyte cells derived from the mice. Moreover, treatment with astaxanthin significantly increased LPS-induced lymphocyte proliferation ex vivo but not Con A-stimulated lymphocyte proliferation ex vivo. Enzyme linked immunosorbent assay (ELISA) analysis revealed that administration of astaxanthin significantly enhanced INF-γ production in response to both LPS and Con A stimulation, whereas IL-2 production increased only in response to Con A stimulation. Also, astaxanthin treatment alone significantly increased IL-2 production in lymphocytes derived from mice, but did not significantly change production of INF-γ. These findings suggest that astaxanthin modulates lymphocytic immune responses in vitro, and that it partly exerts its ex vivo immunomodulatory effects by increasing INF-γ and IL-2 production without inducing cytotoxicity. PMID:26729100

  5. Astaxanthin, a Carotenoid, Stimulates Immune Responses by Enhancing IFN-γ and IL-2 Secretion in Primary Cultured Lymphocytes in Vitro and ex Vivo

    Directory of Open Access Journals (Sweden)

    Kuan-Hung Lin

    2015-12-01

    Full Text Available Astaxanthin, a potent antioxidant carotenoid, plays a major role in modulating the immune response. In this study, we examined the immunomodulatory effects of astaxanthin on cytokine production in primary cultured lymphocytes both in vitro and ex vivo. Direct administration of astaxanthin (70–300 nM did not produce cytotoxicity in lipopolysaccharide (LPS, 100 µg/ mL- or concanavalin A (Con A, 10 µg/ mL-activated lymphocytes, whereas astaxanthin alone at 300 nM induced proliferation of splenic lymphocytes (p < 0.05 in vitro. Although astaxanthin, alone or with Con A, had no apparent effect on interferon (INF-γ and interleukin (IL-2 production in primary cultured lymphocytes, it enhanced LPS-induced INF-γ production. In an ex vivo experiment, oral administration of astaxanthin (0.28, 1.4 and 7 mg/kg/day for 14 days did not cause alterations in the body or spleen weights of mice and also was not toxic to lymphocyte cells derived from the mice. Moreover, treatment with astaxanthin significantly increased LPS-induced lymphocyte proliferation ex vivo but not Con A-stimulated lymphocyte proliferation ex vivo. Enzyme linked immunosorbent assay (ELISA analysis revealed that administration of astaxanthin significantly enhanced INF-γ production in response to both LPS and Con A stimulation, whereas IL-2 production increased only in response to Con A stimulation. Also, astaxanthin treatment alone significantly increased IL-2 production in lymphocytes derived from mice, but did not significantly change production of INF-γ. These findings suggest that astaxanthin modulates lymphocytic immune responses in vitro, and that it partly exerts its ex vivo immunomodulatory effects by increasing INF-γ and IL-2 production without inducing cytotoxicity.

  6. Biosynthesis of tylophora alkaloids

    International Nuclear Information System (INIS)

    Using labelled precursors, biosynthesis of the tylophora alkaloids, tylophorine, tylophorinidine and tylophorinide has been investigated in Tylophora asthmatica plants. The radioactive precursors, phenylalanine-2-14C, benzoic acid-1-14C, benzoic acid-ring 14C, acetate-2-14C, ornithine-5-14C, acetate-2-14C, ornithine-5-14C and cinnamic acid-2-14C were administered to the plants individually by wick technique. Tylophorine was isolated in each case and assayed for its radioactivity to find out the incorporation of the label into it. The results indicate that: (1) phenylalanine via cinnamic acid is an important precursor in the biosynthesis of tylophorine (2) orinithine participates in tylophorine biosynthesis via pyrroline and (3) tylophorinidine may be a direct precursor of tylophorine. (M.G.B.)

  7. Astaxanthin hyperproduction by Phaffia rhodozyma (now Xanthophyllomyces dendrorhous) with raw coconut milk as sole source of energy.

    Science.gov (United States)

    Domíguez-Bocanegra, A R; Torres-Muñoz, J A

    2004-12-01

    Natural carbon sources, such as those present in cane sugar molasses and grape juice, promote the synthesis of astaxanthin in different Phaffia rhodozyma yeasts. One of these, coconut milk, has a very rich nutrient composition. The aim of this work was to investigate the utility of coconut milk as sole source of energy for astaxanthin pigment production by P. rhodozyma strains. Currently, coconut pulp is widely used in industrial processes in Mexico for the production of shampoos, candies, food, etc. However, coconut milk is a waste product. We show that coconut milk enhances astaxanthin production. The fermentation yielded 850 microg/g yeast with the NRRL-10921 wild-type strain and 1850 microg/g yeast with the mutated R1 strain. Production was better than reported results employing other natural carbon sources. PMID:15290135

  8. Efficient Extraction of Astaxanthin from Phaffia rhodozyma with Polar and Non-polar Solvents after Acid Washing

    Institute of Scientific and Technical Information of China (English)

    YIN Chunhua; YANG Shuzhen; LIU Xiaolu; YAN Hai

    2013-01-01

    method of extracting astaxanthin from Phaffia rhodozyma with various solvents after acid washing was investigated.The extraction efficiency was distinctly increased after acid washing of P.rhodozyma cells.When the concentration of HCl was 0.4 mol·L-,the highest extraction efficiency of astaxanthin was achieved which was about three times higher than the control.Acetone or benzene as single polar or non-polar solvent was the most effective solvent in our research.With a combination of isopropanol and n-hexane (volume ratio of 2 ∶ 1),the maximal extraction efficiency was achieved,approximately 60% higher than that obtained with a single solvent.The liquid-solid ratio and the extracting time were also optimized.Under the optimum extraction conditions,the extraction yield of astaxanthin exceeded 98%.

  9. Technical Report on the Development of Mutant Paracoccus strain and Optimization of Medium Composition for the Mass Production of Astaxanthin

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jong Il; Lee, Ju Woon; Kim, Jae Hun; Song, Beom Seok

    2010-08-15

    Astaxanthin is used to role of provitamin A, and it is stronger antioxidant activity than vitamin E (100-500 times higher activity) and other carotenoids (10-fold). Furthermore, astaxanthin is also used as a nutraceutical and a medicinal ingredient against degenerative diseases such as cancer, heart disease, and skin related illness. The objective of this study was develop a carotenoid-hyperproducing mutant of Paracoccus N81106 using gamma irradiation and optimized medium composition. A mutant of Paracoccus having higher carotenoid content was isolated, and the production medium was optimized using response surface methodology. These results support that astaxanthin with strong antioxidant activity could be economically produced using the mutant and will be helpful for the related industry

  10. Technical Report on the Development of Mutant Paracoccus strain and Optimization of Medium Composition for the Mass Production of Astaxanthin

    International Nuclear Information System (INIS)

    Astaxanthin is used to role of provitamin A, and it is stronger antioxidant activity than vitamin E (100-500 times higher activity) and other carotenoids (10-fold). Furthermore, astaxanthin is also used as a nutraceutical and a medicinal ingredient against degenerative diseases such as cancer, heart disease, and skin related illness. The objective of this study was develop a carotenoid-hyperproducing mutant of Paracoccus N81106 using gamma irradiation and optimized medium composition. A mutant of Paracoccus having higher carotenoid content was isolated, and the production medium was optimized using response surface methodology. These results support that astaxanthin with strong antioxidant activity could be economically produced using the mutant and will be helpful for the related industry

  11. Towards elucidating carnosic acid biosynthesis in Lamiaceae:functional characterization of the three first steps of the pathway in Salvia fruticosa and Rosmarinus officinalis

    OpenAIRE

    Dragana Božić; Dimitra Papaefthimiou; Kathleen Brückner; De Vos, Ric C. H.; Tsoleridis, Constantinos A.; Dimitra Katsarou; Antigoni Papanikolaou; Irini Pateraki; Chatzopoulou, Fani M.; Eleni Dimitriadou; Stefanos Kostas; David Manzano; Ulschan Scheler; Albert Ferrer; Alain Tissier

    2015-01-01

    Carnosic acid (CA) is a phenolic diterpene with anti-tumour, anti-diabetic, antibacterial and neuroprotective properties that is produced by a number of species from several genera of theLamiaceae family, including Salvia fruticosa (Cretan sage) and Rosmarinus officinalis(Rosemary). To elucidate CA biosynthesis, glandular trichome transcriptome data of S. fruticosawere mined for terpene synthase genes. Two putative diterpene synthase genes, namelySfCPS and&n...

  12. Functional redundancy of CDP-ethanolamine and CDP-choline pathway enzymes in phospholipid biosynthesis: ethanolamine-dependent effects on steady-state membrane phospholipid composition in Saccharomyces cerevisiae.

    OpenAIRE

    McGee, T. P.; Skinner, H B; Bankaitis, V A

    1994-01-01

    It has been established that yeast membrane phospholipid content is responsive to the inositol and choline content of the growth medium. Alterations in the levels of transcription of phospholipid biosynthetic enzymes contribute significantly to this response. We now describe conditions under which ethanolamine can exert significant influence on yeast membrane phospholipid composition. We demonstrate that mutations which block a defined subset of the reactions required for the biosynthesis of ...

  13. Astaxanthin improves behavioral disorder and oxidative stress in prenatal valproic acid-induced mice model of autism.

    Science.gov (United States)

    Al-Amin, Md Mamun; Rahman, Md Mahbubur; Khan, Fazlur Rahman; Zaman, Fahmida; Mahmud Reza, Hasan

    2015-06-01

    Prenatal exposure to valproic acid on gestational day 12.5 may lead to the impaired behavior in the offspring, which is similar to the human autistic symptoms. To the contrary, astaxanthin shows neuroprotective effect by its antioxidant mechanism. We aimed to (i) develop mice model of autism and (ii) investigate the effect of astaxanthin on such model animals. Valproic acid (600 mg/kg) was administered intraperitoneally to the pregnant mice on gestational day 12.5. Prenatal valproic acid-exposed mice were divided into 2 groups on postnatal day 25 and astaxanthin (2mg/kg) was given to the experimental group (VPA_AST, n=10) while saline was given to the control group (VPA, n=10) for 4 weeks. Behavioral test including social interaction, open field and hot-plate were conducted on postnatal day 25 and oxidative stress markers such as lipid peroxidation, advanced protein oxidation product, nitric oxide, glutathione, and activity of superoxide dismutase and catalase were estimated on postnatal day 26 to confirm mice model of autism and on postnatal day 56 to assess the effect of astaxanthin. On postnatal day 25, prenatal valproic acid-exposed mice exhibited (i) delayed eye opening (ii) longer latency to respond painful stimuli, (iii) poor sociability and social novelty and (iv) high level of anxiety. In addition, an increased level of oxidative stress was found by determining different oxidative stress markers. Treatment with astaxanthin significantly (pfeatures. Astaxanthin improves the impaired behavior in animal model of autism presumably by its antioxidant activity. PMID:25732953

  14. The effect of gamma irradiation on astaxanthin synthetase encoding gene in two mutant strains of Phaffia rhodozyma.

    Directory of Open Access Journals (Sweden)

    Naeimeh Najafi

    2013-09-01

    Full Text Available Astaxanthin, an orange-red carotenoid pigment, acts as a protective agent against oxidative damage to cells in vivo. The astaxanthin synthetase gene (crtS size consists of 3995 bp. This gene has been suggested to catalyse β-carotene to astaxanthin in Phaffia rhodozyma. The aim of this research was to find any possible changes in this gene in two mutant strains, Gam1 and Gam2 (with high astaxanthin pigment production, previously created by gamma irradiation.The astaxanthin synthetase gene sequence of Phaffia rhodozyma in the NCBI Gene bank was used to design primer. In Gam1, this gene was amplified using primers Asta F1, Asta R2, Asta F3, Asta R4. In Gam2, primers asta F1, asta R4 were used to amplify the gene. The amplified fragments were 8 sequenced using primers Asta F1, Asta R1, Asta F2, Asta R2, Asta F3, Asta R3 and Asta F4, Asta R4. Astaxanthin synthetase gene from two mutant strains, Gam1 and Gam2 were amplified using PCR. The amplified products were sequenced and aligned using the ClustalW software.The comparison of this gene showed 98% and 99% similarities between the reference sequence and Gam1 and Gam2 mutant strains, respectively, whereas the comparison of this gene in Gam1 and Gam2 mutant strains showed 97% similarity. However, the deduced proteins showed 78% and 83% between the reference protein obtained from the wild type and Gam1 and Gam2, respectively. This similarity was 75% between the mutant strains.

  15. Effects of homogenization process parameters on physicochemical properties of astaxanthin nanodispersions prepared using a solvent-diffusion technique

    Directory of Open Access Journals (Sweden)

    Anarjan N

    2015-02-01

    Full Text Available Navideh Anarjan,1 Hoda Jafarizadeh-Malmiri,2 Imededdine Arbi Nehdi,3 Hassen Mohamed Sbihi,3 Saud Ibrahim Al-Resayes,3 Chin Ping Tan4 1Young Researchers And Elite Club, Tabriz Branch, Islamic Azad University, Tabriz, Iran; 2Department of Chemical Engineering, Faculty of Food Engineering, Sahand University of Technology, Tabriz, Iran; 3King Saud University, College of Science, Chemistry Department, Riyadh, Saudi Arabia; 4Department of Food Technology, Faculty of Food Science and Technology, Universiti Putra Malaysia, Selangor, Malaysia Abstract: Nanodispersion systems allow incorporation of lipophilic bioactives, such as astaxanthin (a fat soluble carotenoid into aqueous systems, which can improve their solubility, bioavailability, and stability, and widen their uses in water-based pharmaceutical and food products. In this study, response surface methodology was used to investigate the influences of homogenization time (0.5–20 minutes and speed (1,000–9,000 rpm in the formation of astaxanthin nanodispersions via the solvent-diffusion process. The product was characterized for particle size and astaxanthin concentration using laser diffraction particle size analysis and high performance liquid chromatography, respectively. Relatively high determination coefficients (ranging from 0.896 to 0.969 were obtained for all suggested polynomial regression models. The overall optimal homogenization conditions were determined by multiple response optimization analysis to be 6,000 rpm for 7 minutes. In vitro cellular uptake of astaxanthin from the suggested individual and multiple optimized astaxanthin nanodispersions was also evaluated. The cellular uptake of astaxanthin was found to be considerably increased (by more than five times as it became incorporated into optimum nanodispersion systems. The lack of a significant difference between predicted and experimental values confirms the suitability of the regression equations connecting the response

  16. Recent advances in combinatorial biosynthesis for drug discovery

    Directory of Open Access Journals (Sweden)

    Sun H

    2015-02-01

    Full Text Available Huihua Sun,1,* Zihe Liu,1,* Huimin Zhao,1,2 Ee Lui Ang1 1Metabolic Engineering Research Laboratory, Institute of Chemical and Engineering Sciences, Agency for Science, Technology and Research, Singapore; 2Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA *These authors contributed equally to this work Abstract: Because of extraordinary structural diversity and broad biological activities, natural products have played a significant role in drug discovery. These therapeutically important secondary metabolites are assembled and modified by dedicated biosynthetic pathways in their host living organisms. Traditionally, chemists have attempted to synthesize natural product analogs that are important sources of new drugs. However, the extraordinary structural complexity of natural products sometimes makes it challenging for traditional chemical synthesis, which usually involves multiple steps, harsh conditions, toxic organic solvents, and byproduct wastes. In contrast, combinatorial biosynthesis exploits substrate promiscuity and employs engineered enzymes and pathways to produce novel “unnatural” natural products, substantially expanding the structural diversity of natural products with potential pharmaceutical value. Thus, combinatorial biosynthesis provides an environmentally friendly way to produce natural product analogs. Efficient expression of the combinatorial biosynthetic pathway in genetically tractable heterologous hosts can increase the titer of the compound, eventually resulting in less expensive drugs. In this review, we will discuss three major strategies for combinatorial biosynthesis: 1 precursor-directed biosynthesis; 2 enzyme-level modification, which includes swapping of the entire domains, modules and subunits, site-specific mutagenesis, and directed evolution; 3 pathway-level recombination. Recent examples of combinatorial biosynthesis employing these

  17. Conversion of β-carotene into astaxanthin : two separate enzymes or a bifunctional hydroxylase-ketolase protein?

    OpenAIRE

    Gudiña Eduardo; Martín Juan F; Barredo José L

    2008-01-01

    Abstract Astaxanthin is a xanthophyll of great interest in animal nutrition and human health. The market prospect in the nutraceutics industries for this health-protective molecule is very promising. Astaxanthin is synthesized by several bacteria, algae and plants from β-carotene by the sequential action of two enzymes: a β-carotene, 3,3'-hydroxylase that introduces an hydroxyl group at the 3 (and 3') positions of each of the two β-ionone rings of β-carotene, and a β-carotene ketolase that in...

  18. Plant Terpenoids: Biosynthesis and Ecological Functions

    Institute of Scientific and Technical Information of China (English)

    Ai-Xia Cheng; Yong-Gen Lou; Ying-Bo Mao; Shan Lu; Ling-Jian Wang; Xiao-Ya Chen

    2007-01-01

    Among plant secondary metabolites terpenoids are a structurally most diverse group; they function as phytoalexins in plant direct defense, or as signals in indirect defense responses which involves herbivores and their natural enemies. In recent years, more and more attention has been paid to the investigation of the ecological role of plant terpenoids. The biosynthesis pathways of monoterpenes, sesquiterpenes, and diterpenes include the synthesis of C5 precursor isopentenyl diphosphate (IPP) and its allylic isomer dimethylallyl diphosphate (DMAPP), the synthesis of the immediate diphosphate precursors, and the formation of the diverse terpenoids. Terpene synthases (TPSs) play a key role in volatile terpene synthesis. By expression of the TPS genes, significant achievements have been made on metabolic engineering to increase terpenoid production. This review mainly summarizes the recent research progress in elucidating the ecological role of terpenoids and characterization of the enzymes involved in the terpenoid biosynthesis. Spatial and temporal regulations of terpenoids metabolism are also discussed.

  19. Acylphloroglucinol Biosynthesis in Strawberry Fruit.

    Science.gov (United States)

    Song, Chuankui; Ring, Ludwig; Hoffmann, Thomas; Huang, Fong-Chin; Slovin, Janet; Schwab, Wilfried

    2015-11-01

    Phenolics have health-promoting properties and are a major group of metabolites in fruit crops. Through reverse genetic analysis of the functions of four ripening-related genes in the octoploid strawberry (Fragaria × ananassa), we discovered four acylphloroglucinol (APG)-glucosides as native Fragaria spp. fruit metabolites whose levels were differently regulated in the transgenic fruits. The biosynthesis of the APG aglycones was investigated by examination of the enzymatic properties of three recombinant Fragaria vesca chalcone synthase (FvCHS) proteins. CHS is involved in anthocyanin biosynthesis during ripening. The F. vesca enzymes readily catalyzed the condensation of two intermediates in branched-chain amino acid metabolism, isovaleryl-Coenzyme A (CoA) and isobutyryl-CoA, with three molecules of malonyl-CoA to form phlorisovalerophenone and phlorisobutyrophenone, respectively, and formed naringenin chalcone when 4-coumaroyl-CoA was used as starter molecule. Isovaleryl-CoA was the preferred starter substrate of FvCHS2-1. Suppression of CHS activity in both transient and stable CHS-silenced fruit resulted in a substantial decrease of APG glucosides and anthocyanins and enhanced levels of volatiles derived from branched-chain amino acids. The proposed APG pathway was confirmed by feeding isotopically labeled amino acids. Thus, Fragaria spp. plants have the capacity to synthesize pharmaceutically important APGs using dual functional CHS/(phloriso)valerophenone synthases that are expressed during fruit ripening. Duplication and adaptive evolution of CHS is the most probable scenario and might be generally applicable to other plants. The results highlight that important promiscuous gene function may be missed when annotation relies solely on in silico analysis. PMID:26169681

  20. Improved aqueous solubility of crystalline astaxanthin (3,3'-dihydroxy-beta, beta-carotene-4,4'-dione) by Captisol (sulfobutyl ether beta-cyclodextrin).

    Science.gov (United States)

    Lockwood, Samuel F; O'Malley, Sean; Mosher, Gerold L

    2003-04-01

    Carotenoids are the most widely distributed natural pigments, with over 600 individual compounds identified and characterized from natural sources. A few are commercially important molecules, having found utility as additions to animal feed in the aquaculture, poultry, and swine feed industries. The majority are lipophilic molecules with near zero inherent aqueous solubility. Many different methods have been developed to make the carotenoids "water dispersible," as true water solubility has not been described. Astaxanthin (3,3'-dihydroxy-beta, beta-carotene-4,4'-dione) is a commercially important oxygenated carotenoid that has gained wide acceptance as a feed additive in the $50 billion salmon and trout aquaculture industry. Recently, interest in the human health applications of astaxanthin has increased, with astaxanthin receiving approval as a dietary supplement in several countries, including the United States. Moving astaxanthin into a pharmaceutical application will require a chemical delivery system that overcomes the problems with parenteral administration of a highly lipophilic, low molecular weight compound. In the current study, the ability of sulfobutyl ether beta-cyclodextrin (sodium), as the Captisol(R) brand, to increase the aqueous water solubility of crystalline astaxanthin was evaluated. Complexation of crystalline astaxanthin with Captisol increased the apparent water solubility of crystalline astaxanthin approximately 71-fold, to a concentration in the 2 microg/mL range. It is unlikely that this increase in solubility will result in a pharmaceutically acceptable chemical delivery system for humans. However, the increased aqueous solubility of crystalline astaxanthin to the range achieved in the current study will likely find utility in the introduction of crystalline astaxanthin into mammalian cell culture systems that have previously been dependent upon liposomes, or toxic organic solvents, for the introduction of carotenoids into aqueous

  1. Recent advances in the elucidation of enzymatic function in natural product biosynthesis [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Tan Gao-Yi

    2015-12-01

    Full Text Available With the successful production of artemisinic acid in yeast, the promising potential of synthetic biology for natural product biosynthesis is now being realized. The recent total biosynthesis of opioids in microbes is considered to be another landmark in this field. The importance and significance of enzymes in natural product biosynthetic pathways have been re-emphasized by these advancements. Therefore, the characterization and elucidation of enzymatic function in natural product biosynthesis are undoubtedly fundamental for the development of new drugs and the heterologous biosynthesis of active natural products. Here, discoveries regarding enzymatic function in natural product biosynthesis over the past year are briefly reviewed.

  2. Recent advances in the elucidation of enzymatic function in natural product biosynthesis [version 2; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Gao-Yi Tan

    2016-02-01

    Full Text Available With the successful production of artemisinic acid in yeast, the promising potential of synthetic biology for natural product biosynthesis is now being realized. The recent total biosynthesis of opioids in microbes is considered to be another landmark in this field. The importance and significance of enzymes in natural product biosynthetic pathways have been re-emphasized by these advancements. Therefore, the characterization and elucidation of enzymatic function in natural product biosynthesis are undoubtedly fundamental for the development of new drugs and the heterologous biosynthesis of active natural products. Here, discoveries regarding enzymatic function in natural product biosynthesis over the past year are briefly reviewed.

  3. Determination of astaxanthin concentration in Rainbow trout (Oncorhynchus mykiss) by multispectral image analysis

    DEFF Research Database (Denmark)

    Frosch, Stina; Dissing, Bjørn Skovlund; Ersbøll, Bjarne Kjær;

    extraction of astaxanthin from the minced sample into a suitable solvent such as acetone or hexane before further analysis. The existing methods have several drawbacks including being destructive and labour consuming. Current state-of-the art vision systems for quality and process control in the fish...... processing industries are typically based on traditional trichromatic (Red Green Blue) imaging. The relative presence of some wavelengths and absence of others is a specific characteristic of many material properties. Consequently, the adaption of multispectral imaging technology can reveal relevant...

  4. Xyloglucan and its biosynthesis

    Directory of Open Access Journals (Sweden)

    Olga A Zabotina

    2012-06-01

    Full Text Available The hemicellulosic polysaccharide xyloglucan (XyG, found in the primary cell walls of most plant tissues, is important for structural organization of the cell wall and regulation of growth and development. Significant recent progress in structural characterization of XyGs from different plant species has shed light on the diversification of XyG during plant evolution. Also, identification of XyG biosynthetic enzymes and examination of their interactions suggests the involvement of a multiprotein complex in XyG biosynthesis. This mini-review presents an updated overview of the diversity of XyG structures in plant taxa and recent findings on XyG biosynthesis.

  5. Insights on the evolution of trehalose biosynthesis

    Directory of Open Access Journals (Sweden)

    Morett Enrique

    2006-12-01

    Full Text Available Abstract Background The compatible solute trehalose is a non-reducing disaccharide, which accumulates upon heat, cold or osmotic stress. It was commonly accepted that trehalose is only present in extremophiles or cryptobiotic organisms. However, in recent years it has been shown that although higher plants do not accumulate trehalose at significant levels they have actively transcribed genes encoding the corresponding biosynthetic enzymes. Results In this study we show that trehalose biosynthesis ability is present in eubacteria, archaea, plants, fungi and animals. In bacteria there are five different biosynthetic routes, whereas in fungi, plants and animals there is only one. We present phylogenetic analyses of the trehalose-6-phosphate synthase (TPS and trehalose-phosphatase (TPP domains and show that there is a close evolutionary relationship between these domains in proteins from diverse organisms. In bacteria TPS and TPP genes are clustered, whereas in eukaryotes these domains are fused in a single protein. Conclusion We have demonstrated that trehalose biosynthesis pathways are widely distributed in nature. Interestingly, several eubacterial species have multiple pathways, while eukaryotes have only the TPS/TPP pathway. Vertebrates lack trehalose biosynthetic capacity but can catabolise it. TPS and TPP domains have evolved mainly in parallel and it is likely that they have experienced several instances of gene duplication and lateral gene transfer.

  6. New insights into regulation of anthocyanin biosynthesis in fruits

    OpenAIRE

    Jaakola, Laura

    2013-01-01

    Anthocyanins are important health-promoting pigments that make a major contribution to the quality of fruits. The biosynthetic pathway leading to anthocyanins is well known and the key regulatory genes controlling the pathway have been isolated in many species. Recently, a considerable amount of new information has been gathered on the developmental and environmental regulation of anthocyanin biosynthesis in fruits, specifically the impact of regulation through light. New discoveries have beg...

  7. Phosphonate Biosynthesis and Catabolism: A Treasure Trove of Unusual Enzymology

    OpenAIRE

    Peck, Spencer C.; van der Donk, Wilfred A.

    2013-01-01

    Natural product biosynthesis has proven a fertile ground for the discovery of novel chemistry. Herein we review the progress made in elucidating the biosynthetic pathways of phosphonate and phosphinate natural products such as the antibacterial compounds dehydrophos and fosfomycin, the herbicidal phosphinothricin-containing peptides, and the antimalarial compound FR-900098. In each case, investigation of the pathway has yielded unusual, and often unprecedented, biochemistry. Likewise, recent ...

  8. ENDOCANNABINOIDS AND EICOSAMOIDS: BIOSYNTHESIS AND INTERACTIONS WITH IMMUNE RESPONSE

    Directory of Open Access Journals (Sweden)

    Yu. K. Karaman

    2014-07-01

    Full Text Available The review is dedicated to modern concepts of arachidonic acid metabolites, i.e., endocannabinoids and eicosanoids, their biosynthetic pathways, cross-talk mechanisms and participation in immune response. New information from literature and own results include data concerning overlapping enzymatic pathways controlling biosynthesis of endocannabinoids and eicosanoids. Impact of synthetic cannabinoid receptor ligands upon production rates of proinflammatory cytokines and eicosanoids is discussed, as like as relationships among immune system reactivity and expression levels of cannabinoid receptors.

  9. Self-assembly and energy transfer in artificial light-harvesting complexes of bacteriochlorophyll c with astaxanthin

    Czech Academy of Sciences Publication Activity Database

    Alster, J.; Polívka, Tomáš; Arellano, J.B.; Hříbek, P.; Vácha, František; Hala, J.; Pšenčík, J.

    2012-01-01

    Roč. 111, 1-2 (2012), s. 193-204. ISSN 0166-8595 R&D Projects: GA ČR GA206/09/0375 Institutional research plan: CEZ:AV0Z50510513 Keywords : light-harvesting * astaxanthin * self-assembly * bacteriochlorophyll aggregates Subject RIV: BO - Biophysics Impact factor: 3.150, year: 2012

  10. Production of astaxanthin from corn fiber as a value-added co-product of fuel ethanol fermentation

    Science.gov (United States)

    Five strains of the yeast Phaffia rhodozyma, NRRL Y-17268, NRRL Y-17270, ATCC 96594 (CBS 6938), ATCC 24202 (UCD 67-210), and ATCC 74219 (UBV-AX2) were tested for astaxanthin production using the major sugars derived from corn fiber, a byproduct from the wet milling of corn kernels that contains prim...

  11. Study on the interaction of β-carotene and astaxanthin with trypsin and pepsin by spectroscopic techniques.

    Science.gov (United States)

    Li, Xiangrong; Li, Peihong

    2016-05-01

    β-Carotene and astaxanthin are two carotenoids with powerful antioxidant properties, but the binding mechanisms of β-carotene/astaxanthin to proteases remain unclear. In this study, the interaction of these two carotenoids with trypsin and pepsin was investigated using steady-state and time-resolved fluorescence measurements, synchronous fluorescence spectroscopy, UV-vis absorption spectroscopy and circular dichroism (CD) spectroscopy. The experimental results indicated that the quenching mechanisms of trypsin/pepsin by the two carotenoids are static processes. The binding constants of trypsin and pepsin with these two carotenoids are in the following order: astaxanthin-trypsin > astaxanthin-pepsin > β-carotene-trypsin > β-carotene-pepsin, respectively. Thermodynamic investigations revealed that the interaction between the two carotenoids and trypsin/pepsin is synergistically driven by enthalpy and entropy, and hydrophobic forces and electrostatic attraction have a significant role in the reactions. In addition, as shown by synchronous fluorescence spectroscopy, UV-vis absorption spectroscopy and CD, the two carotenoids may induce conformational and microenvironmental changes in trypsin/pepsin. The study provides an accurate and full basic data for clarifying the binding mechanisms of the two carotenoids with trypsin/pepsin and is helpful in understanding their effect on protein function and their biological activity in vivo. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26358735

  12. Accumulation of Astaxanthin by a New Haematococcus pluvialis Strain BM1 from the White Sea Coastal Rocks (Russia

    Directory of Open Access Journals (Sweden)

    Konstantin Chekanov

    2014-08-01

    Full Text Available We report on a novel arctic strain BM1 of a carotenogenic chlorophyte from a coastal habitat with harsh environmental conditions (wide variations in solar irradiance, temperature, salinity and nutrient availability identified as Haematococcus pluvialis Flotow. Increased (25‰ salinity exerted no adverse effect on the growth of the green BM1 cells. Under stressful conditions (high light, nitrogen and phosphorus deprivation, green vegetative cells of H. pluvialis BM1 grown in BG11 medium formed non-motile palmelloid cells and, eventually, hematocysts capable of a massive accumulation of the keto-carotenoid astaxanthin with a high nutraceutical and therapeutic potential. Routinely, astaxanthin was accumulated at the level of 4% of the cell dry weight (DW, reaching, under prolonged stress, 5.5% DW. Astaxanthin was predominantly accumulated in the form of mono- and diesters of fatty acids from C16 and C18 families. The palmelloids and hematocysts were characterized by the formation of red-colored cytoplasmic lipid droplets, increasingly large in size and number. The lipid droplets tended to merge and occupied almost the entire volume of the cell at the advanced stages of stress-induced carotenogenesis. The potential application of the new strain for the production of astaxanthin is discussed in comparison with the H. pluvialis strains currently employed in microalgal biotechnology.

  13. Effects of astaxanthin and emodin on the growth, stress resistance and disease resistance of yellow catfish (Pelteobagrus fulvidraco).

    Science.gov (United States)

    Liu, Fei; Shi, Hong-Zhuan; Guo, Qiao-Sheng; Yu, Ye-Bing; Wang, Ai-Ming; Lv, Fu; Shen, Wen-Biao

    2016-04-01

    Yellow catfish (Pelteobagrus fulvidraco) has become a commercially important fish species in China and eastern Asia. High-density aquaculture has led to congestion and excessive stress and contributed to bacterial infection outbreaks that have caused high mortality. We investigated the effects of dietary supplementation with astaxanthin and emodin alone and in combination on the growth and stress resistance of yellow catfish. After 60 days of feeding, each group of fish (control, astaxanthin, emodin, and astaxanthin plus emodin (combination) groups) was exposed to acute crowding stress for 24 h, and a subsample of fish from the four groups was challenged with the bacterial septicemia pathogen Proteus mirabilis after the end of the crowding stress experiment. Compared with the control, the astaxanthin and emodin groups showed increases in serum total protein (TP), hepatic superoxide dismutase (SOD) activity and hepatic heat shock proteins 70 (HSP70) mRNA levels at 12 and 24 h after the initiation of crowding stress. The combination group exhibited increases in alanine aminotransferase (ALT) activity, aspartate aminotransferase (AST) activity, serum TP, hepatic SOD activity and hepatic HSP70 mRNA levels within 24 h after the initiation of crowding stress. However, decreases relative to the control were observed in the serum cortisol and glucose contents in the three treatment groups at 12 and 24 h after the initiation of crowding stress, in ALT and AST activity in the astaxanthin and emodin group at 24 h after the initiation of crowding stress, and in the serum lysozyme activity, serum alkaline phosphatase (ALP) activity, and hepatic catalase (CAT) and malondialdehyde (MDA) activity in the combination group at 24 h after the initiation of crowding stress. Additionally, the cumulative mortality after P. mirabilis infection was lower in all three treatment groups (57.00%-70.33%) than in the control (77.67%). Dietary supplementation with astaxanthin and emodin

  14. Final Report on Regulation of Guaiacyl and Syringyl Monolignol Biosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Vincent L. Chiang

    2006-03-09

    The focus of this research is to understand syringyl monolignol biosynthesis that leads to the formation of syringyl lignin, a type of lignin that can be easily removed during biomass conversion. We have achieved the three originally proposed goals for this project. (1) SAD and CAD genes (enzyme catalytic and kinetic properties) and their functional relevance to CAld5H/AldOMT pathway, (2) spatiotemporal expression patterns of Cald5H, AldOMT, SAD and CAD genes, and (3) functions of CAld5H, AldOMT, and SAD genes in vivo using transgenic aspen. Furthermore, we also found that microRNA might be involved in the upstream regulatory network of lignin biosynthesis and wood formation. The achievements are as below. (1) Based on biochemical and molecular studies, we discovered a novel syringyl-specific alcohol dehydrogenase (SAD) involved in monolignol biosynthesis in angiosperm trees. Through CAld5H/OMT/SAD mediation, syringyl monolignol biosynthesis branches out from guaiacyl pathway at coniferaldehyde; (2) The function of CAld5H gene in this syringyl monolignol biosynthesis pathway also was confirmed in vivo in transgenic Populus; (3) The proposed major monolignol biosynthesis pathways were further supported by the involving biochemical functions of CCR based on a detailed kinetic study; (4) Gene promoter activity analysis also supported the cell-type specific expression of SAD and CAD genes in xylem tissue, consistent with the cell-specific locations of SAD and CAD proteins and with the proposed pathways; (5) We have developed a novel small interfering RNA (siRNA)-mediated stable gene-silencing system in transgenic plants; (6) Using the siRNA and P. trichocarpa transformation/regeneration systems we are currently producing transgenic P. trichocarpa to investigate the interactive functions of CAD and SAD in regulating guaiacyl and syringyl lignin biosynthesis; (7) We have cloned for the first time from a tree species, P. trichocarpa, small regulatory RNAs termed micro

  15. Jasmonate-induced biosynthesis of andrographolide in Andrographis paniculata.

    Science.gov (United States)

    Sharma, Shiv Narayan; Jha, Zenu; Sinha, Rakesh Kumar; Geda, Arvind Kumar

    2015-02-01

    Andrographolide is a prominent secondary metabolite found in Andrographis paniculata that exhibits enormous pharmacological effects. In spite of immense value, the normal biosynthesis of andrographolide results in low amount of the metabolite. To induce the biosynthesis of andrographolide, we attempted elicitor-induced activation of andrographolide biosynthesis in cell cultures of A. paniculata. This was carried out by using methyl jasmonate (MeJA) as an elicitor. Among the various concentrations of MeJA tested at different time periods, 5 µM MeJA yielded 5.25 times more andrographolide content after 24 h of treatment. The accumulation of andrographolide was correlated with the expression level of known regulatory genes (hmgs, hmgr, dxs, dxr, isph and ggps) of mevalonic acid (MVA) and 2-C-methyl-d-erythritol-4-phosphate (MEP) pathways. These results established the involvement of MeJA in andrographolide biosynthesis by inducing the transcription of its biosynthetic pathways genes. The coordination of isph, ggps and hmgs expression highly influenced the andrographolide biosynthesis. PMID:25104168

  16. Biosynthesis and functions of sulfur modifications in tRNA

    Directory of Open Access Journals (Sweden)

    Naoki eShigi

    2014-04-01

    Full Text Available Sulfur is an essential element for a variety of cellular constituents in all living organisms. In tRNA molecules, there are many sulfur-containing nucleosides, such as the derivatives of 2‑thiouridine (s2U, 4-thiouridine (s4U, 2-thiocytidine (s2C, and 2-methylthioadenosine (ms2A. Earlier studies established the functions of these modifications for accurate and efficient translation, including proper recognition of the codons in mRNA or stabilization of tRNA structure. In many cases, the biosynthesis of these sulfur modifications starts with cysteine desulfurases, which catalyze the generation of persulfide (an activated form of sulfur from cysteine. Many sulfur-carrier proteins are responsible for delivering this activated sulfur to each biosynthesis pathway. Finally, specific modification enzymes activate target tRNAs and then incorporate sulfur atoms. Intriguingly, the biosynthesis of 2-thiouridine in all domains of life is functionally and evolutionarily related to the ubiquitin-like post-translational modification system of cellular proteins in eukaryotes. This review summarizes the recent characterization of the biosynthesis of sulfur modifications in tRNA and the novel roles of this modification in cellular functions in various model organisms, with a special emphasis on 2-thiouridine derivatives. Each biosynthesis pathway of sulfur-containing molecules is mutually modulated via sulfur trafficking, and 2-thiouridine and codon usage bias have been proposed to control the translation of specific genes.

  17. Biosynthesis and functions of sulfur modifications in tRNA.

    Science.gov (United States)

    Shigi, Naoki

    2014-01-01

    Sulfur is an essential element for a variety of cellular constituents in all living organisms. In tRNA molecules, there are many sulfur-containing nucleosides, such as the derivatives of 2-thiouridine (s(2)U), 4-thiouridine (s(4)U), 2-thiocytidine (s(2)C), and 2-methylthioadenosine (ms(2)A). Earlier studies established the functions of these modifications for accurate and efficient translation, including proper recognition of the codons in mRNA or stabilization of tRNA structure. In many cases, the biosynthesis of these sulfur modifications starts with cysteine desulfurases, which catalyze the generation of persulfide (an activated form of sulfur) from cysteine. Many sulfur-carrier proteins are responsible for delivering this activated sulfur to each biosynthesis pathway. Finally, specific "modification enzymes" activate target tRNAs and then incorporate sulfur atoms. Intriguingly, the biosynthesis of 2-thiouridine in all domains of life is functionally and evolutionarily related to the ubiquitin-like post-translational modification system of cellular proteins in eukaryotes. This review summarizes the recent characterization of the biosynthesis of sulfur modifications in tRNA and the novel roles of this modification in cellular functions in various model organisms, with a special emphasis on 2-thiouridine derivatives. Each biosynthesis pathway of sulfur-containing molecules is mutually modulated via sulfur trafficking, and 2-thiouridine and codon usage bias have been proposed to control the translation of specific genes. PMID:24765101

  18. Application of derivative ratio spectrophotometry for determination of β-carotene and astaxanthin from Phaffia rhodozyma extract

    Institute of Scientific and Technical Information of China (English)

    NI Hui; HE Guo-qing; RUAN Hui; CHEN Qi-he; CHEN Feng

    2005-01-01

    A derivative ratio spectrophotometric method was used for the simultaneous determination of β-carotene and astaxanthin produced from Phaffia rhodozyma. Absorbencies of a series of the standard carotenoids in the range of 441 nm to 490nm demonstrated that their absorptive spectra accorded with Beer's law and that the additivity when the concentrations of β-carotene and astaxanthin and their mixture were within the range of 0 to 5 μg/ml, 0 to 6 μg/ml, and 0 to 6 μg/ml, respectively.When the wavelength interval (△λ) at 2 nm was selected to calculate the first derivative ratio spectra values, the first derivative amplitudes at 461 nm and 466 nm were suitable for quantitatively determining β-carotene and astaxanthin, respectively. Effect of divisor on derivative ratio spectra could be neglected; any concentration used as divisor in range of 1.0 to 4.0 μg/ml is ideal for calculating the derivative ratio spectra values of the two carotenoids. Calibration graphs were established for β-carotene within 0-6.0 μg/ml and for astaxanthin within 0-5.0 μg/ml with their corresponding regressive equations in: y=-0.0082x-0.0002 and y=0.0146x-0.0006, respectively. R-square values in excess of 0.999 indicated the good linearity of the calibration graphs. Sample recovery rates were found satisfactory (>99%) with relative standard deviations (RSD) of less than 5%. This method was successfully applied to simultaneous determination of β-carotene and astaxanthin in the laboratory-prepared mixtures and the extract from the Phaffia rhodozyma culture.

  19. Biosynthesis of Taxadiene in Saccharomyces cerevisiae : Selection of Geranylgeranyl Diphosphate Synthase Directed by a Computer-Aided Docking Strategy

    OpenAIRE

    Ding, Ming-Zhu; Yan, Hui-fang; Li, Lin-Feng; Zhai, Fang; Shang, Lu-Qing; Yin, Zheng; Yuan, Ying-jin

    2014-01-01

    Identification of efficient key enzymes in biosynthesis pathway and optimization of the fitness between functional modules and chassis are important for improving the production of target compounds. In this study, the taxadiene biosynthesis pathway was firstly constructed in yeast by transforming ts gene and overexpressing erg20 and thmgr. Then, the catalytic capabilities of six different geranylgeranyl diphosphate synthases (GGPPS), the key enzyme in mevalonic acid (MVA) pathway catalyzing f...

  20. Astaxanthin in the calanoid copepod Calanus helgolandicus: dynamics of esterfication and vertical distribution in the German Bight, North Sea.

    OpenAIRE

    Sommer, Frank; Agurto, Cristian; Henriksen, Peter; Kioerboe, Thomas

    2006-01-01

    Zooplankton synthesise astaxanthin, a carotenoid pigment believed to protect against high-energy irradiance, from precursors in their diet. Different patterns of astaxanthin vertical distribution would be expected from the benefits of photoprotection, the costs of visual predation and the availability of food. Despite a highly resolved sampling approach (4 m depth intervals), no clear pattern of vertical distribution or correlation with chlorophyll a concentrations was found for Calanus helgo...

  1. Biotin biosynthesis in Mycobacterium tuberculosis: physiology, biochemistry and molecular intervention.

    Science.gov (United States)

    Salaemae, Wanisa; Azhar, Al; Booker, Grant W; Polyak, Steven W

    2011-09-01

    Biotin is an important micronutrient that serves as an essential enzyme cofactor. Bacteria obtain biotin either through de novo synthesis or by active uptake from exogenous sources. Mycobacteria are unusual amongst bacteria in that their primary source of biotin is through de novo synthesis. Here we review the importance of biotin biosynthesis in the lifecycle of Mycobacteria. Genetic screens designed to identify key metabolic processes have highlighted a role for the biotin biosynthesis in bacilli growth, infection and survival during the latency phase. These studies help to establish the biotin biosynthetic pathway as a potential drug target for new anti-tuberculosis agents. PMID:21976058

  2. Biotin biosynthesis in Mycobacterium tuberculosis: physiology, biochemistry and molecular intervention

    Institute of Scientific and Technical Information of China (English)

    Wanisa Salaemae; Al Azhar; Grant W. Booker; Steven W. Polyak

    2011-01-01

    Biotin is an important micronutrient that serves as an essential enzyme cofactor.Bacteria obtain biotin either through de novo synthesis or by active uptake from exogenous sources.Mycobacteria are unusual amongst bacteria in that their primary source of biotin is through de novo synthesis.Here we review the importance of biotin biosynthesis in the lifecycle of Mycobacteria.Genetic screens designed to identify key metabolic processes have highlighted a role for the biotin biosynthesis in bacilli growth,infection and survival during the latency phase.These studies help to establish the biotin biosynthetic pathway as a potential drug target for new anti-tuberculosis agents.

  3. Topical problems in the biosynthesis of red blood pigment

    Energy Technology Data Exchange (ETDEWEB)

    Franck, B.

    1982-05-01

    Uroporphyrinogen III plays a key role in the biosynthesis of heme, the red pigment of blood. In vivo studies with specifically /sup 14/C- and /sup 3/H-labeled precursors have revealed that the formation of uroporphyrinogen III in the organism follows several primary and subsidiary pathways. Model experiments on the pattern of biosynthesis have led to simple and effective methods of synthesizing uroporphyrin analogs and have shown that their production is strongly favored thermodynamically. The biologically important porphyrins thus available permit a mechanistic explanation of the light-induced dermatoses in porphyria diseases and suggest promising medical applications in diagnosis and therapy.

  4. Topical problems in the biosynthesis of red blood pigment

    International Nuclear Information System (INIS)

    Uroporphyrinogen III plays a key role in the biosynthesis of heme, the red pigment of blood. In vivo studies with specifically 14C- and 3H-labeled precursors have revealed that the formation of uroporphyrinogen III in the organism follows several primary and subsidiary pathways. Model experiments on the pattern of biosynthesis have led to simple and effective methods of synthesizing uroporphyrin analogs and have shwon that their production is strongly favored thermodynamically, The biologically important porphyrins thus available permit a mechanistic explanantion of the light-induced dermatoses in porphyria diseases and suggest promising medical applications in diagnosis and therapy. (orig.)

  5. Terpene Biosynthesis: Modularity Rules

    OpenAIRE

    Oldfield, Eric; Lin, Fu-Yang

    2011-01-01

    Terpenes are the largest class of small molecule natural products on Earth, and the most abundant by mass. Here, we summarize recent developments in elucidating the structure and function of the proteins involved in their biosynthesis. There are 6 main building blocks or modules (α,β,γ,δ,ε and ζ) that make up the structures of these enzymes: the αα and αδ head-to-tail trans-prenyl transferases that produce trans-isoprenoid diphosphates from C5 precursors; the ε head-to-head prenyl transferase...

  6. Biosynthesis and Metabolic Fate of Phenylalanine in Conifers.

    Science.gov (United States)

    Pascual, María B; El-Azaz, Jorge; de la Torre, Fernando N; Cañas, Rafael A; Avila, Concepción; Cánovas, Francisco M

    2016-01-01

    The amino acid phenylalanine (Phe) is a critical metabolic node that plays an essential role in the interconnection between primary and secondary metabolism in plants. Phe is used as a protein building block but it is also as a precursor for numerous plant compounds that are crucial for plant reproduction, growth, development, and defense against different types of stresses. The metabolism of Phe plays a central role in the channeling of carbon from photosynthesis to the biosynthesis of phenylpropanoids. The study of this metabolic pathway is particularly relevant in trees, which divert large amounts of carbon into the biosynthesis of Phe-derived compounds, particularly lignin, an important constituent of wood. The trunks of trees are metabolic sinks that consume a considerable percentage of carbon and energy from photosynthesis, and carbon is finally immobilized in wood. This paper reviews recent advances in the biosynthesis and metabolic utilization of Phe in conifer trees. Two alternative routes have been identified: the ancient phenylpyruvate pathway that is present in microorganisms, and the arogenate pathway that possibly evolved later during plant evolution. Additionally, an efficient nitrogen recycling mechanism is required to maintain sustained growth during xylem formation. The relevance of phenylalanine metabolic pathways in wood formation, the biotic interactions, and ultraviolet protection is discussed. The genetic manipulation and transcriptional regulation of the pathways are also outlined. PMID:27468292

  7. Regulation of Brassinosteroid Biosynthesis and Inactivation

    Institute of Scientific and Technical Information of China (English)

    Baolin Zhao; Jia Li

    2012-01-01

    Brassinosteroids (BRs) are a group of naturally-occurring steroidal phytohormones playing fundamental roles during normal plant growth and development.Using a combination of experimental approaches,including analytical chemistry,genetics,and biochemistry,the major BR biosynthetic pathway has been largely elucidated.The least-understood knowledge in the BR research field is probably the molecular mechanisms controlling the bioactive levels of BRs in response to various developmental and environmental cues.In this review,we focus our discussion on a recently-proposed,8-step predominant BR biosynthetic pathway,several newly-identified transcription factors regulating the expression of key enzymes that catalyze BR biosynthesis,and up-to-date information about the mechanisms that plants use to inactivate unnecessary BRs.

  8. Biosynthesis of archaeal membrane ether lipids.

    Science.gov (United States)

    Jain, Samta; Caforio, Antonella; Driessen, Arnold J M

    2014-01-01

    A vital function of the cell membrane in all living organism is to maintain the membrane permeability barrier and fluidity. The composition of the phospholipid bilayer is distinct in archaea when compared to bacteria and eukarya. In archaea, isoprenoid hydrocarbon side chains are linked via an ether bond to the sn-glycerol-1-phosphate backbone. In bacteria and eukarya on the other hand, fatty acid side chains are linked via an ester bond to the sn-glycerol-3-phosphate backbone. The polar head groups are globally shared in the three domains of life. The unique membrane lipids of archaea have been implicated not only in the survival and adaptation of the organisms to extreme environments but also to form the basis of the membrane composition of the last universal common ancestor (LUCA). In nature, a diverse range of archaeal lipids is found, the most common are the diether (or archaeol) and the tetraether (or caldarchaeol) lipids that form a monolayer. Variations in chain length, cyclization and other modifications lead to diversification of these lipids. The biosynthesis of these lipids is not yet well understood however progress in the last decade has led to a comprehensive understanding of the biosynthesis of archaeol. This review describes the current knowledge of the biosynthetic pathway of archaeal ether lipids; insights on the stability and robustness of archaeal lipid membranes; and evolutionary aspects of the lipid divide and the LUCA. It examines recent advances made in the field of pathway reconstruction in bacteria. PMID:25505460

  9. Purine biosynthesis de novo by lymphocytes in gout

    International Nuclear Information System (INIS)

    A method of measurement in vitro of purine biosynthesis de novo in human circulating blood lymphocytes is proposed. The rate of early reactions of purine biosynthesis de novo was determined by the incorporation of [14C]formate into N-formyl glycinamide ribonucleotide when the subsequent reactions of the metabolic pathway were completely inhibited by the antibiotic azaserine. Synthesis of 14C-labelled N-formyl glycinamide ribonucleotide by lymphocytes was measured in healthy control subjects and patients with primary gout or hyperuricaemia secondary to renal failure, with or without allopurinol therapy. The average synthesis was higher in gouty patients without therapy than in control subjects, but the values contained overlap the normal range. In secondary hyperuricaemia the synthesis was at same value as in control subjects. These results are in agreement with the inconstant acceleration of purine biosynthesis de novo in gouty patients as seen by others with measurement of [14C]glycine incorporation into urinary uric acid. (author)

  10. Genetic regulations of the biosynthesis of microbial surfactants: an overview.

    Science.gov (United States)

    Das, Palashpriya; Mukherjee, Soumen; Sen, Ramkrishna

    2008-01-01

    Microbial biosurfactants are surface active metabolites synthesized by microbes growing on a variety of substrates. In spite of having great potential for commercial, therapeutic and environmental applications, industrial level production has not been realized for their low yields and productivities. One vital factor determining their biosynthesis is the genetic makeup of the producer organisms. Studies on molecular genetics and biochemistry of the synthesis of several biosurfactants have revealed the operons, the enzymes and the metabolic pathways required for their extracellular production. Surfactin, a cyclic lipopeptide biosurfactant is a potent antimicrobial agent and is produced as a result of non-ribosomal biosynthesis catalyzed by a large multienzyme peptide synthetase complex called the surfactin synthetase. Pathways for the synthesis of other lipopeptides such as iturin, lichenysin and arthrofactin are also mediated by similar enzyme complexes. These non-ribosomal peptide synthetases (NRPSs) responsible for lipopeptide biosynthesis display a high degree of structural similarity among themselves even from distant microbial species. Plasmid-encoded- rhlA, B, R and I genes of rhl quorum sensing system are required for production of glycolipid biosurfactants by Pseudomonas species. Molecular genetics of biosynthesis of alasan and emulsan by Acinetobacter species and of the fungal biosurfactants such as mannosylerythritol lipids (MEL) and hydrophobins have been deciphered. However, limited genetic information is available about biosynthesis of other biosurfactants such as viscosin, amphisin and putisolvin produced by some strains of Pseudomonas species. Understanding of the genetic regulatory mechanisms would help to develop metabolically engineered hyper-producing strains with better product characteristics and acquired capability of utilizing cheap agro-industrial wastes as substrates. This article thus provides an overview of the role and importance of

  11. Extraction and purification of high-value metabolites from microalgae: essential lipids, astaxanthin and phycobiliproteins.

    Science.gov (United States)

    Cuellar-Bermudez, Sara P; Aguilar-Hernandez, Iris; Cardenas-Chavez, Diana L; Ornelas-Soto, Nancy; Romero-Ogawa, Miguel A; Parra-Saldivar, Roberto

    2015-03-01

    The marked trend and consumers growing interest in natural and healthy products have forced researches and industry to develop novel products with functional ingredients. Microalgae have been recognized as source of functional ingredients with positive health effects since these microorganisms produce polyunsaturated fatty acids, polysaccharides, natural pigments, essential minerals, vitamins, enzymes and bioactive peptides. For this reason, the manuscript reviews two of the main high-value metabolites which can be obtained from microalgae: pigments and essential lipids. Therefore, the extraction and purification methods for polyunsaturated fatty acids, astaxanthin, phycoerythrin and phycocyanin are described. Also, the effect that environmental growth conditions have in the production of these metabolites is described. This review summarizes the existing methods to extract and purify such metabolites in order to develop a feasible and sustainable algae industry. PMID:25223877

  12. Excited state properties of the astaxanthin radical cation: A quantum chemical study

    Science.gov (United States)

    Dreuw, Andreas; Starcke, Jan Hendrik; Wachtveitl, Josef

    2010-07-01

    Using time-dependent density functional theory, the excited electronic states of the astaxanthin radical cation (AXT rad + ) are investigated. While the optically allowed excited D 1 and D 3 states are typical ππ∗ excited states, the D 2 and D 4 states are nπ∗ states. Special emphasis is put onto the influence of the carbonyl groups onto the excited states. For this objective, the excited states of four hypothetical carotenoids and zeaxanthin have been computed. Addition of a carbonyl group to a conjugated carbon double bond system does essentially not change the vertical excitation energies of the optically allowed ππ∗ states due to two counter-acting effects: the excitation energy should increase due to the -M-effect of the carbonyl group and at the same time decrease owing to the elongation of the conjugated double bond system by the carbonyl group itself.

  13. Crystallisation of alpha-crustacyanin, the lobster carapace astaxanthin-protein: results from EURECA

    Science.gov (United States)

    Zagalsky, P. F.; Wright, C. E.; Parsons, M.

    1995-08-01

    Crystallisation of alpha-crustacyanin, the lobster carapace astaxanthin-protein was attempted under microgravity conditions in EURECA satellite using liquid-liquid diffusion with polyethyleneglycol (PEG) as precipitant; in a second reaction chamber phenol and dioxan were used as additives to prevent composite crystal growth. Crystals of alpha-crustacyanin grown under microgravity from PEG were larger than those grown terrestrially in the same apparatus under otherwise identical conditions. On retrieval, the crystals from PEG were shown to be composite and gave a powder diffraction pattern. The second reaction chamber showed leakage on retrieval and had also been subjected to rapid temperature variation during flight. Crystal fragments were nevertheless recovered but showed a powder diffraction pattern. It is concluded, certainly for liquid-liquid diffusion using PEG alone, that, for crustacyanin, although microgravity conditions resulted in an increase in dimensions of crystals, a measurable improvement in molecular ordering was not achieved.

  14. Bistable aggregate of all-trans-astaxanthin in an aqueous solution

    Science.gov (United States)

    Mori, Yuso; Yamano, Kuniko; Hashimoto, Hideki

    1996-05-01

    The temperature dependence of the optical absorption spectra for astaxanthin aggregate has been studied between 2 and 32°C. Red-shifted absorption bands as compared to the monomer absorption band are found above 21°C in addition to the blue-shifted band of the aggregate. The spectra suggest that the molecular arrangement in the aggregate is a bistable one consisting of head-to-tail and card-packed arrangements. A diagram describing the bistability together with the monomer state is proposed in the space defined by the free energy and the quantity of Σi = 1 N< θ12 + < σθ12 for the ith molecule in the N-molecule aggregate.

  15. Excited state properties of the astaxanthin radical cation: A quantum chemical study

    Energy Technology Data Exchange (ETDEWEB)

    Dreuw, Andreas, E-mail: andreas.dreuw@theochem.uni-frankfurt.de [Institute of Physical and Theoretical Chemistry, Goethe-University Frankfurt, Max von Laue-Str. 7, 60438 Frankfurt am Main (Germany); Starcke, Jan Hendrik; Wachtveitl, Josef [Institute of Physical and Theoretical Chemistry, Goethe-University Frankfurt, Max von Laue-Str. 7, 60438 Frankfurt am Main (Germany)

    2010-07-19

    Using time-dependent density functional theory, the excited electronic states of the astaxanthin radical cation (AXT{sup {center_dot}+}) are investigated. While the optically allowed excited D{sub 1} and D{sub 3} states are typical {pi}{pi}* excited states, the D{sub 2} and D{sub 4} states are n{pi}* states. Special emphasis is put onto the influence of the carbonyl groups onto the excited states. For this objective, the excited states of four hypothetical carotenoids and zeaxanthin have been computed. Addition of a carbonyl group to a conjugated carbon double bond system does essentially not change the vertical excitation energies of the optically allowed {pi}{pi}* states due to two counter-acting effects: the excitation energy should increase due to the -M-effect of the carbonyl group and at the same time decrease owing to the elongation of the conjugated double bond system by the carbonyl group itself.

  16. Excited state properties of the astaxanthin radical cation: A quantum chemical study

    International Nuclear Information System (INIS)

    Using time-dependent density functional theory, the excited electronic states of the astaxanthin radical cation (AXT·+) are investigated. While the optically allowed excited D1 and D3 states are typical ππ* excited states, the D2 and D4 states are nπ* states. Special emphasis is put onto the influence of the carbonyl groups onto the excited states. For this objective, the excited states of four hypothetical carotenoids and zeaxanthin have been computed. Addition of a carbonyl group to a conjugated carbon double bond system does essentially not change the vertical excitation energies of the optically allowed ππ* states due to two counter-acting effects: the excitation energy should increase due to the -M-effect of the carbonyl group and at the same time decrease owing to the elongation of the conjugated double bond system by the carbonyl group itself.

  17. Excited states and electrochromism of radical cation of the carotenoid astaxanthin

    Science.gov (United States)

    Krawczyk, Stanisław

    1998-09-01

    Radical cations of the carotenoid astaxanthin were generated by chemical oxidation with Fe(Cl) 3, and their absorption and electroabsorption (Stark) spectra at temperatures about 150 K were recorded in the spectral range from 5900 to 26000 cm -1 (380 to 1700 nm), covering two absorptive electronic transitions from D 0 (ground) to D 1 and D 2 excited states. The changes in static polarizability are negative and equal -40±10 A 3 for D 0→D 1 and -105±15 A 3 for D 0→D 2, pointing that dominant contribution to polarizabilities results from the coupling of D 1 and D 2 with the ground state. An approximate localization of the next excited state with ground-state parity is estimated based on arguments from perturbation theory.

  18. Extraction and purification of high-value metabolites from microalgae: essential lipids, astaxanthin and phycobiliproteins

    Science.gov (United States)

    Cuellar-Bermudez, Sara P; Aguilar-Hernandez, Iris; Cardenas-Chavez, Diana L; Ornelas-Soto, Nancy; Romero-Ogawa, Miguel A; Parra-Saldivar, Roberto

    2015-01-01

    The marked trend and consumers growing interest in natural and healthy products have forced researches and industry to develop novel products with functional ingredients. Microalgae have been recognized as source of functional ingredients with positive health effects since these microorganisms produce polyunsaturated fatty acids, polysaccharides, natural pigments, essential minerals, vitamins, enzymes and bioactive peptides. For this reason, the manuscript reviews two of the main high-value metabolites which can be obtained from microalgae: pigments and essential lipids. Therefore, the extraction and purification methods for polyunsaturated fatty acids, astaxanthin, phycoerythrin and phycocyanin are described. Also, the effect that environmental growth conditions have in the production of these metabolites is described. This review summarizes the existing methods to extract and purify such metabolites in order to develop a feasible and sustainable algae industry. PMID:25223877

  19. The Metal Cation Chelating Capacity of Astaxanthin. Does This Have Any Influence on Antiradical Activity?

    Directory of Open Access Journals (Sweden)

    Ana Martínez

    2012-01-01

    Full Text Available In this Density Functional Theory study, it became apparent that astaxanthin (ASTA may form metal ion complexes with metal cations such as Ca+2, Cu+2, Pb+2, Zn+2, Cd+2 and Hg+2. The presence of metal cations induces changes in the maximum absorption bands which are red shifted in all cases. Therefore, in the case of compounds where metal ions are interacting with ASTA, they are redder in color. Moreover, the antiradical capacity of some ASTA-metal cationic complexes was studied by assessing their vertical ionization energy and vertical electron affinity, reaching the conclusion that metal complexes are slightly better electron donors and better electron acceptors than ASTA.

  20. Biosynthesis of plant sulfolipids

    International Nuclear Information System (INIS)

    The complete biosynthesis of sulfoquinovosyldiacylglycerol (SQDG) remains undetermined although dark synthesis of SQDG by chloroplasts supplied with AP35S, PAP35S or 35SO4 plus ATP suggests the sulfur moiety arises from either APS or sulfite (1). Sulfate incorporation into sulfolipids in isolated chloroplasts and in intact roots is reported here and compared to lipids labelled by 14C-acetate or 14C-glycerol. Several unknown 35S-labelled chloroform-soluble compounds were isolated from sterile roots. These 35S-labelled compounds differ from those of the chloroplast, identified as elemental sulfur forms. Identification of the unknown root compounds is in progress. Unlike chloroplast, isolated root plastids do not synthesis SQDG from sulfate plus ATP suggesting a requirement for an activated form of sulfate, such as APS or PAPS

  1. Roles of lignin biosynthesis and regulatory genes in plant development.

    Science.gov (United States)

    Yoon, Jinmi; Choi, Heebak; An, Gynheung

    2015-11-01

    Lignin is an important factor affecting agricultural traits, biofuel production, and the pulping industry. Most lignin biosynthesis genes and their regulatory genes are expressed mainly in the vascular bundles of stems and leaves, preferentially in tissues undergoing lignification. Other genes are poorly expressed during normal stages of development, but are strongly induced by abiotic or biotic stresses. Some are expressed in non-lignifying tissues such as the shoot apical meristem. Alterations in lignin levels affect plant development. Suppression of lignin biosynthesis genes causes abnormal phenotypes such as collapsed xylem, bending stems, and growth retardation. The loss of expression by genes that function early in the lignin biosynthesis pathway results in more severe developmental phenotypes when compared with plants that have mutations in later genes. Defective lignin deposition is also associated with phenotypes of seed shattering or brittle culm. MYB and NAC transcriptional factors function as switches, and some homeobox proteins negatively control lignin biosynthesis genes. Ectopic deposition caused by overexpression of lignin biosynthesis genes or master switch genes induces curly leaf formation and dwarfism. PMID:26297385

  2. Astaxanthin from Crayfish (Procambarus clarkii as a Pigmentary Ingredient in the Feed of Laying Hens

    Directory of Open Access Journals (Sweden)

    Garrido-Fernández, J.

    2008-06-01

    Full Text Available Chicken egg yolks generally owe their color to yellow carotenoids. The addition of synthetic red pigments allows changes in color, from the original yellow to red hues which may be more appealing to consumers in certain markets.Our aim has been to test whether ground crayfish shells, which are a rich and natural source of astaxanthin, produce detectable changes in the coloration of egg yolks through the accumulation of this carotenoid. Laying hens were fed with a commercial feed mixed with crayfish powder and the carotenoid profiles of the yolks in the eggs laid during the trial were monitored by HPLC. The analyses showed a progressive increase in the astaxanthin concentration in the egg yolks, reaching similar levels to those obtained for the rest of present carotenoid pigments.La yema de huevo de gallina debe su coloración a la presencia de carotenoides de tonalidad amarilla. La adición de colorantes sintéticos de tonalidades rojas permite modificar e incrementar la coloración de la yema desde el amarillo original a tonos rojos que pueden ser demandados en ciertos mercados según las preferencias del consumidor. El objetivo del trabajo fue probar si un triturado obtenido a partir de caparazones de cangrejo, que es una fuente natural y rica en astaxanteno, produce cambios detectables en la coloración de la yema de huevo por la acumulación de dicho carotenoide. Las gallinas ponedoras se alimentaron con un pienso comercial al que se adicionó triturado de caparazón de cangrejo. Se realizó un seguimiento de los cambios en la composición carotenoide (mediante HPLC de la yema de los huevos puestos durante el periodo de alimentación suplementada. Los análisis mostraron una progresiva incorporación de astaxanteno que alcanzó niveles similares al resto de carotenoides presentes inicialmente en la yema.

  3. Effect of astaxanthin and cholesterol on growth, survival, and pigmentation of adult spiny lobster, Panulirus ornatus (Decapoda, Palinuridae

    Directory of Open Access Journals (Sweden)

    Lai V. Hung

    2010-11-01

    Full Text Available Prior research on the spiny lobster Panulirus ornatus (Fabricius, 1798 determined thatintermediate levels of cholesterol are important in diets, but astaxanthin may not be. Here we examinedhow the growth, survival and coloration of spiny lobster were influenced by the inclusion of bothastaxanthin (50, 60 and 70 mg.kg-1 and cholesterol (0.3, 0.4 and 0.5 % in a two factor experiment.Overall, survival was 84.8% with no significant difference among dietary treatments. Lobsters grew thebest when fed the diet containing the lowest cholesterol and greatest astaxanthin of the levels presented.The results of this study point out the need to examine the effects of dietary component addition acrossa range of inclusion levels simultaneously for multiple nutrients.

  4. Biological variation of lipid constituents and distribution of tocopherols and astaxanthin in farmed Atlantic salmon (Salmo salar)

    DEFF Research Database (Denmark)

    Refsgaard, Hanne; Brockhoff, Per B; Jensen, Benny

    1998-01-01

    The contents of fat, astaxanthin, and tocogherols and the fatty acid composition of a homogeneous group of 145 farmed Atlantic salmon (Salmo salar) were determined. The analytical variation of the data was stastistically-separated from the biological variation. The fat content in the muscle near...... concentrations of alpha-, gamma-, and delta-tocopherols were approximately 32, 2.9, and 0.4 mg/kg of muscle, respectively, and the biological standard deviations were 4.5, 0.4, and 0.07 mg/kg (14, 14, and 20%), respectively. in another group of five salmon the distributions throughout the fillet were determined......, longitudinally as well as transversally. The distribution of fat, astaxanthin, and tocopherols varied throughout the salmon. The fatty acid composition varied little between extracts from different locations of the fillet...

  5. Gradient domestication of Haematococcus pluvialis mutant with 15% CO2 to promote biomass growth and astaxanthin yield.

    Science.gov (United States)

    Cheng, Jun; Li, Ke; Yang, Zongbo; Lu, Hongxiang; Zhou, Junhu; Cen, Kefa

    2016-09-01

    In order to increase biomass yield and reduce culture cost of Haematococcus pluvialis with flue gas from coal-fired power plants, a screened mutant by nuclear irradiation was gradually domesticated with 15% CO2 to promote biomass dry weight and astaxanthin yield. The biomass yield of mutant after 10 generations of 15% CO2 domestication increased to 1.3 times as that with air. With the optimization of nitrogen and phosphorus concentration, the biomass dry weight was further increased by 62%. The astaxanthin yield induced with 15% CO2 and high light of 135 μmol photons m(-2) s(-1) increased to 87.4mg/L, which was 6 times higher than that induced with high light in air. PMID:27259189

  6. Astaxanthin protects against MPP+-induced oxidative stress in PC12 cells via the HO-1/NOX2 axis

    OpenAIRE

    Ye Qinyong; Huang Bixia; Zhang Xiaodong; Zhu Yuangui; Chen Xiaochun

    2012-01-01

    Abstract Background Although the etiology of PD remains unclear, increasing evidence has shown that oxidative stress plays an important role in its pathogenesis and that of other neurodegenerative disorders. NOX2, a cytochrome subunit of NOX, transports electrons across the plasma membrane to generate ROS, leading to physiological and pathological processes. Heme oxygenase-1 (HO-1) can be rapidly induced by oxidative stress and other noxious stimuli in the brain or other tissues. Astaxanthin ...

  7. Astaxanthin Attenuates the Apoptosis of Retinal Ganglion Cells in db/db Mice by Inhibition of Oxidative Stress

    OpenAIRE

    Xiao-Li Kang; Gao Lu; Ling-Yan Dong; Jie Jin

    2013-01-01

    Diabetic retinopathy is a common diabetic eye disease caused by changes in retinal ganglion cells (RGCs). It is an ocular manifestation of systemic disease, which affects up to 80% of all patients who have had diabetes for 10 years or more. The genetically diabetic db / db mouse, as a model of type-2 diabetes, shows diabetic retinopathy induced by apoptosis of RGCs. Astaxanthin is a carotenoid with powerful antioxidant properties that exists naturally in various plants, algae and seafood. Her...

  8. Astaxanthin vs placebo on arterial stiffness, oxidative stress and inflammation in renal transplant patients (Xanthin: a randomised controlled trial

    Directory of Open Access Journals (Sweden)

    Robertson Iain K

    2008-12-01

    Full Text Available Abstract Background There is evidence that renal transplant recipients have accelerated atherosclerosis manifest by increased cardiovascular morbidity and mortality. The high incidence of atherosclerosis is, in part, related to increased arterial stiffness, vascular dysfunction, elevated oxidative stress and inflammation associated with immunosuppressive therapy. The dietary supplement astaxanthin has shown promise as an antioxidant and anti-inflammatory therapeutic agent in cardiovascular disease. The aim of this trial is to investigate the effects of astaxanthin supplementation on arterial stiffness, oxidative stress and inflammation in renal transplant patients. Method and Design This is a randomised, placebo controlled clinical trial. A total of 66 renal transplant recipients will be enrolled and allocated to receive either 12 mg/day of astaxanthin or an identical placebo for one-year. Patients will be stratified into four groups according to the type of immunosuppressant therapy they receive: 1 cyclosporine, 2 sirolimus, 3 tacrolimus or 4 prednisolone+/-azathioprine, mycophenolate mofetil or mycophenolate sodium. Primary outcome measures will be changes in 1 arterial stiffness measured by aortic pulse wave velocity (PWV, 2 oxidative stress assessed by plasma isoprostanes and 3 inflammation by plasma pentraxin 3. Secondary outcomes will include changes in vascular function assessed using the brachial artery reactivity (BAR technique, carotid artery intimal medial thickness (CIMT, augmentation index (AIx, left ventricular afterload and additional measures of oxidative stress and inflammation. Patients will undergo these measures at baseline, six and 12 months. Discussion The results of this study will help determine the efficacy of astaxanthin on vascular structure, oxidative stress and inflammation in renal transplant patients. This may lead to a larger intervention trial assessing cardiovascular morbidity and mortality. Trial Registration

  9. Identification of astaxanthin diglucoside diesters from snow alga Chlamydomonas nivalis by liquid chromatography – atmospheric pressure chemical ionization mass spectrometry

    Czech Academy of Sciences Publication Activity Database

    Řezanka, Tomáš; Nedbalová, Linda; Sigler, Karel; Cepák, Vladislav

    2008-01-01

    Roč. 69, č. 2 (2008), s. 479-490. ISSN 0031-9422 R&D Projects: GA MŠk 1M0571; GA AV ČR(CZ) KJB601110509 Institutional research plan: CEZ:AV0Z50200510; CEZ:AV0Z60050516 Keywords : chlamydomonas nivalis * snow alga * astaxanthin diglucoside diesters Subject RIV: EE - Microbiology, Virology Impact factor: 2.946, year: 2008

  10. Kinetics of reactive oxygen species produced by rainbow trout (Oncorhynchus mykiss) leukocytes and the effect of the antioxidant astaxanthin

    OpenAIRE

    Gómez, L; Cortés, Raúl; Valenzuela, A.; Smith, C. T.

    2014-01-01

    Reactive oxygen species contribute to kill of microorganisms. Their activity is usually measured by their capacity to reduce nitroblue tetrazolium into formazan. The incubation time to allow nitroblue tetrazolium reduction by reactive oxygen species usually ranges from 30 to 60 min. The aim of our study was to determine the kinetics of formazan formation, to determine the shortest incubation time possible, and to find if astaxanthin negatively affects the availability of reactive oxygen speci...

  11. Dietary Carotenoids Regulate Astaxanthin Content of Copepods and Modulate Their Susceptibility to UV Light and Copper Toxicity

    OpenAIRE

    Carman, Kevin R.; Silva, Soraya J.; Maria-José Caramujo; Carla C. C. R. de Carvalho

    2012-01-01

    High irradiation and the presence of xenobiotics favor the formation of reactive oxygen species in marine environments. Organisms have developed antioxidant defenses, including the accumulation of carotenoids that must be obtained from the diet. Astaxanthin is the main carotenoid in marine crustaceans where, among other functions, it scavenges free radicals thus protecting cell compounds against oxidation. Four diets with different carotenoid composition were used to culture the meiobenthic c...

  12. Astaxanthin Supplementation Delays Physical Exhaustion and Prevents Redox Imbalances in Plasma and Soleus Muscles of Wistar Rats

    OpenAIRE

    Tatiana G. Polotow; Cristina V. Vardaris; Andrea R. Mihaliuc; Marina S. Gonçalves; Benedito Pereira; Douglas Ganini; Barros, Marcelo P.

    2014-01-01

    Astaxanthin (ASTA) is a pinkish-orange carotenoid commonly found in marine organisms, especially salmon. ASTA is a powerful antioxidant and suggested to provide benefits for human health, including the inhibition of LDL oxidation, UV-photoprotection, and prophylaxis of bacterial stomach ulcers. Exercise is associated to overproduction of free radicals in muscles and plasma, with pivotal participation of iron ions and glutathione (GSH). Thus, ASTA was studied here as an auxiliary supplement to...

  13. Isolation and Characterization of a Marine Microalga for Biofuel Production with Astaxanthin as a Co-Product

    OpenAIRE

    Zhiyong Liu; Chenfeng Liu; Yuyong Hou; Shulin Chen; Dongguang Xiao; Juankun Zhang; Fangjian Chen

    2013-01-01

    Microalgae have been considered as a promising biomass for biofuel production, but freshwater resource consumption during the scaled-up cultivation are still a challenge. Obtaining robust marine strains capable of producing triacylglycerols and high value-added metabolites are critical for overcoming the limitations of water resources and economical feasibility. In this study, a marine microalga with lipid and astaxanthin accumulation capability was isolated from Bohai Bay, China. The alga wa...

  14. Astaxanthin from Crayfish (Procambarus clarkii) as a Pigmentary Ingredient in the Feed of Laying Hens

    OpenAIRE

    Garrido-Fernández, J.; Cascajo-Almenara, M. V.; Mínguez-Mosquera, M. I.; Negro-Balmaseda, J. J.; Pérez-Gálvez, A.

    2008-01-01

    Chicken egg yolks generally owe their color to yellow carotenoids. The addition of synthetic red pigments allows changes in color, from the original yellow to red hues which may be more appealing to consumers in certain markets.Our aim has been to test whether ground crayfish shells, which are a rich and natural source of astaxanthin, produce detectable changes in the coloration of egg yolks through the accumulation of this carotenoid. Laying hens were fed with a commercial feed mixed with cr...

  15. Overexpression of SbMyb60 impacts phenylpropanoid biosynthesis and alters secondary cell wall composition in sorghum bicolor

    Science.gov (United States)

    The phenylpropanoid biosynthesis pathway that generates lignin subunits represents a significant target to alter the abundance and composition of lignin. The major regulators of phenylpropanoid metabolism are myb transcription factors, which have been shown to modulate secondary cell wall compositi...

  16. Metabolic engineering of chloroplasts for artemisinic acid biosynthesis and impact on plant growth

    Indian Academy of Sciences (India)

    Bhawna Saxena; Mayavan Subramaniyan; Karan Malhotra; Neel Sarovar Bhavesh; Shobha Devi Potlakayala; Shashi Kumar

    2014-03-01

    Chloroplasts offer high-level transgene expression and transgene containment due to maternal inheritance, and are ideal hosts for biopharmaceutical biosynthesis via multigene engineering. To exploit these advantages, we have expressed 12 enzymes in chloroplasts for the biosynthesis of artemisinic acid (precursor of artemisinin, antimalarial drug) in an alternative plant system. Integration of transgenes into the tobacco chloroplast genome via homologous recombination was confirmed by molecular analysis, and biosynthesis of artemisinic acid in plant leaf tissues was detected with the help of 13C NMR and ESI-mass spectrometry. The excess metabolic flux of isopentenyl pyrophosphate generated by an engineered mevalonate pathway was diverted for the biosynthesis of artemisinic acid. However, expression of megatransgenes impacted the growth of the transplastomic plantlets. By combining two exogenous pathways, artemisinic acid was produced in transplastomic plants, which can be improved further using better metabolic engineering strategies for commercially viable yield of desirable isoprenoid products.

  17. Subcellular Localization of Enzymes Involved in Indole Alkaloid Biosynthesis in Catharanthus roseus1

    Science.gov (United States)

    De Luca, Vincenzo; Cutler, Adrian J.

    1987-01-01

    The subcellular localization of enzymes involved in indole alkaloid biosynthesis in leaves of Catharanthus roseus has been investigated. Tryptophan decarboxylase and strictosidine synthase which together produce strictosidine, the first indole alkaloid of this pathway, are both cytoplasmic enzymes. S-Adenosyl-l-methionine: 16-methoxy-2,3-dihydro-3-hydroxytabersonine-N-methyltransferase which catalyses the third to last step in vindoline biosynthesis could be localized in the chloroplasts of Catharanthus leaves and is specifically associated with thylakoids. Acetyl-coenzyme-A-deacetylvindoline-O-acetyltransferase which catalyses the last step in vindoline biosynthesis could also be localized in the cytoplasm. The participation of the chloroplast in this pathway suggests that indole alkaloid intermediates enter and exit this compartment during the biosynthesis of vindoline. PMID:16665811

  18. Astaxanthin and papilioerythrinone in the skin of birds: a chromatic convergence of two metabolic routes with different precursors?

    Science.gov (United States)

    García-de Blas, Esther; Mateo, Rafael; Guzmán Bernardo, Francisco Javier; Rodríguez Martín-Doimeadios, Rosa Carmen; Alonso-Alvarez, Carlos

    2014-05-01

    Carotenoids are organic pigments involved in several important physiological functions and may serve as indicators of individual quality in animals. These pigments are only obtained by animals from the diet, but they can be later transformed into other carotenoids by specific enzymatic reactions. The diet of farm-reared and probably wild red-legged partridges ( Alectoris rufa) is mainly based on cereals that contain high levels of lutein and zeaxanthin. These two carotenoids are also predominant in internal tissues and blood of red-legged partridges. However, in their integuments, astaxanthin and papilioerythrinone (the last one identified in this work) are mainly present in their free form and esterified with fatty acids. According to available literature about carotenoid metabolism in animals, we propose that astaxanthin ( λ max = 478 nm) and papilioerythrinone ( λ max = 452-478 nm) are the result of a chromatic convergence of the transformation of dietary zeaxanthin and lutein, respectively. Moreover, the results obtained in this work provide the first identification by liquid chromatography coupled to accurate mass quadrupole time-of-flight mass spectrometer system of papilioerythrinone ( m/z 581.3989 [M + H]+) in the skin (i.e., not feathers) of a vertebrate. Astaxanthin and papilioerythrinone are very close in terms of chemical structure and coloration, and the combination of these two keto-carotenoids is responsible for the red color of the ornaments in red-legged partridges.

  19. Isolation and Characterization of a Marine Microalga for Biofuel Production with Astaxanthin as a Co-Product

    Directory of Open Access Journals (Sweden)

    Shulin Chen

    2013-05-01

    Full Text Available Microalgae have been considered as a promising biomass for biofuel production, but freshwater resource consumption during the scaled-up cultivation are still a challenge. Obtaining robust marine strains capable of producing triacylglycerols and high value-added metabolites are critical for overcoming the limitations of water resources and economical feasibility. In this study, a marine microalga with lipid and astaxanthin accumulation capability was isolated from Bohai Bay, China. The alga was named as Coelastrum sp. HA-1 based on its morphological and molecular identification. The major characteristics of HA-1 and the effects of nitrogen on its lipid and astaxanthin accumulations were investigated. Results indicated that the highest biomass, lipid and astaxanthin yields achieved were 50.9 g m−2 day−1, 18.0 g m−2 day−1 and 168.9 mg m−2 day−1, respectively, after cultivation for 24 days. The fatty acids of HA-1, identified in their majority as oleic acid (56.6% and palmitic acid (25.9%, are desirable biofuel feedstocks. In addition, this alga can be harvested with simple sedimentation, achieving 98.2% removal efficiency after settling for 24 h. These results suggest that Coelastrum sp. HA-1 has several desirable key features that make it a potential candidate for biofuel production.

  20. Effect of dietary astaxanthin on free radical scavenging capacity and nitrite stress tolerance of postlarvae shrimp, Pleoticus muelleri.

    Science.gov (United States)

    Díaz, Ana Cristina; Velurtas, Susana María; Espino, María Laura; Fenucci, Jorge Lino

    2014-12-24

    The aim of this study was to investigate the effect of astaxanthin feed supplementation and environmental nitrite stress in postlarvae of Pleoticus muelleri (15 ± 0.004 mg initial weight) under culture conditions. Diets containing three levels of astaxanthin, 0 mg kg(-1) of diet (C0), 100 mg kg(-1) of diet (C(100)), and 300 mg kg(-1) of diet (C(300)), were used. Postlarvae fed with each diet were exposed to different concentrations of nitrite (NO(2)Na) (0-200 mg L(-1)). The 96 h median lethal concentration (LC50) values of nitrite N were 76.3, 89.7, and 157 mg L(-1) for shrimps fed to C0, C(100), and C(300). The scavenging properties were evaluated against the stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical by electron resonance spectroscopy (EPR). For all feed treatments, the extracts exhibited strong DPPH scavenging activity; however, shrimp fed with C(100) and C(300) showed the greatest activity to quench DPPH (62 and 59%, respectively) with respect to C0 (43%). It can be concluded that astaxanthin acts as a protector of nitrite stress in P. muelleri. PMID:25427235

  1. Medium optimization to improve astaxanthin production of Xanthophyllomyces dendrorhous mutant W6-8 based on genetic algorithms

    Institute of Scientific and Technical Information of China (English)

    WangWenjun; YuLongjiang; HePu; ZhouPengpeng

    2004-01-01

    Genetic algorithms (GA) based on the principle of mimicing Darwinian evolution and survival of the fittest in a natural environment was used to optimize the medium for astaxanthin production by the mutant strain W6-8 of Xantho-phyllomyces dendrorhous. The 50 concentration levels of 6 medium components were optimized within 50 experiments (full experimental plan: 506 experiments). The results showed that GA could be applied in the medium optimization and better results were obtained. By employing optimized medium components (glucose 39.8 g l-1, yeast extract 4.08 g l-1,(NH4)2SO4 7.36 g l-1, MgSO4 2 g l-1, K2HPO4 2.04 g l-1 and KH2PO4 3.48 g l-1), the highest astaxanthin production was 9.855 mg l-1, approximately 31% higher than that under the initial conditions, and was approximately 15.46% higher than that by orthogonal array but only slightly higher than that by response surface methodology. In the sequent scale-up experiments, the astaxanthin yield was obtained approximately 14.753 mg l-1, employing the optimal medium. The results indicated that GA, as an euiicient method for medium optimization, was superior to other optimal means such as orthogonal array.

  2. Phytoecdysteroids: Diversity, Biosynthesis and Distribution

    Czech Academy of Sciences Publication Activity Database

    Dinan, L.; Harmatha, Juraj; Volodin, V.; Lafont, R.

    Dordrecht : Springer Netherlands , 2009 - (Smagghe, G.), s. 3-45 ISBN 978-1-4020-9111-7 Institutional research plan: CEZ:AV0Z40550506 Keywords : ecdysteroid * phytosterol * structure * biosynthesis Subject RIV: CC - Organic Chemistry

  3. Random sequencing of an induced Taxus cell cDNA library for identification of clones involved in Taxol biosynthesis

    OpenAIRE

    Jennewein, Stefan; Wildung, Mark R.; Chau, MyDoanh; Walker, Kevin; Croteau, Rodney

    2004-01-01

    Biosynthesis of the anticancer drug Taxol involves 19 enzymatic steps from the universal diterpenoid progenitor geranylgeranyl diphosphate derived by the plastidial methylerythritol phosphate pathway for isoprenoid precursor supply. To gain further insight about Taxol biosynthesis relevant to the improved production of this drug and to draw inferences about the organization, regulation, and origins of this complex natural product pathway, random sequencing of a cDNA library derived from Taxus...

  4. Biosynthesis of Anthocyanins and Their Regulation in Colored Grapes

    Directory of Open Access Journals (Sweden)

    Guo-Liang Yan

    2010-12-01

    Full Text Available Anthocyanins, synthesized via the flavonoid pathway, are a class of crucial phenolic compounds which are fundamentally responsible for the red color of grapes and wines. As the most important natural colorants in grapes and their products, anthocyanins are also widely studied for their numerous beneficial effects on human health. In recent years, the biosynthetic pathway of anthocyanins in grapes has been thoroughly investigated. Their intracellular transportation and accumulation have also been further clarified. Additionally, the genetic mechanism regulating their biosynthesis and the phytohormone influences on them are better understood. Furthermore, due to their importance in the quality of wine grapes, the effects of the environmental factors and viticulture practices on anthocyanin accumulation are being investigated increasingly. The present paper summarizes both the basic information and the most recent advances in the study of the anthocyanin biosynthesis in red grapes, emphasizing their gene structure, the transcriptional factors and the diverse exterior regulation factors.

  5. Unraveling the biosynthesis of pilocarpine in Pilocarpus microphyllus.

    Science.gov (United States)

    Sawaya, Alexandra Christine Helena Frankland; Costa, Yanna Dias; Mazzafera, Paulo

    2015-05-01

    Pilocarpine is found exclusively in species of Pilocarpus and the presence of other imidazole alkaloids has been reported in several species of the genus. Pilocarpine has several important pharmaceutical applications. Although several imidazole alkaloids related to pilocarpine have been reported in the previous years, little is still known about its biosynthetic route. At most, histidine has been reported as the precursor of pilocarpine. Based on our own previous reports and in an experiment where pilocarpine and related alkaloids (pilosine, trachyllophiline and anhydropilosine) were supplied to P. microphyllus leaves and the alkaloid profile analyzed by UPLC-MS, we suggest a biosynthesis pathway for pilocarpine. Further experiments using labeled precursors associated with transcriptome data may allow us to understand the whole biosynthesis pathway and its genetic control. PMID:26058143

  6. A sea of biosynthesis: marine natural products meet the molecular age†

    OpenAIRE

    Lane, Amy L.; Moore, Bradley S.

    2010-01-01

    The years 2000 through mid-2010 marked a transformational period in understanding of the biosynthesis of marine natural products. During this decade the field emerged from one largely dominated by chemical approaches to understanding biosynthetic pathways to one incorporating the full force of modern molecular biology and bioinformatics. Fusion of chemical and biological approaches yielded great advances in understanding the genetic and enzymatic basis for marine natural product biosynthesis....

  7. Exopolysaccharides from yeast: insight into optimal conditions for biosynthesis, chemical composition and functional properties – review

    OpenAIRE

    Iwona Gientka; Stanisław Błażejak; Lidia Stasiak-Różańska; Anna Chlebowska-Śmigiel

    2015-01-01

    The yeast exopolysaccharides (EPS) are not a well-established group of metabolites. An industrial scale    of this EPS production is limited mainly by low yield biosynthesis. Until now, enzymes and biosynthesis pathways, as well as the role of regulatory genes, have not been described. Some of yeast EPS show anti- tumor, immunostimulatory and antioxidant activity. Others, absorb heavy metals and can function as bioac- tive components of food. Also, the potential of yeast EPS as...

  8. Conserved enzymes mediate the early reactions of carotenoid biosynthesis in nonphotosynthetic and photosynthetic prokaryotes.

    OpenAIRE

    G. A. Armstrong; Alberti, M; Hearst, J E

    1990-01-01

    Carotenoids comprise one of the most widespread classes of pigments found in nature. The first reactions of C40 carotenoid biosynthesis proceed through common intermediates in all organisms, suggesting the evolutionary conservation of early enzymes from this pathway. We report here the nucleotide sequence of three genes from the carotenoid biosynthesis gene cluster of Erwinia herbicola, a nonphotosynthetic epiphytic bacterium, which encode homologs of the CrtB, CrtE, and CrtI proteins of Rhod...

  9. Potential implications for epigenetic regulation of carotenoid biosynthesis during root and shoot development

    OpenAIRE

    Cazzonelli, Christopher Ian; Yin, Kuide; Pogson, Barry J.

    2009-01-01

    Major regulators of carotenoid biosynthesis have remained rather elusive even though the flux through the branch in the carotenoid pathway can affect plant development in response to environmental stimuli, such as light. Our recent investigations demonstrated that the production of the most abundant carotenoid in plants, lutein, is regulated by carotenoid isomerase (CRTISO) activity at a rate-limiting step of this branch point in carotenoid biosynthesis. CRTISO is required to isomerase cis-ca...

  10. Trypanosoma cruzi Response to Sterol Biosynthesis Inhibitors: Morphophysiological Alterations Leading to Cell Death

    OpenAIRE

    Kessler, Rafael Luis; Soares, Maurilio José; Probst, Christian Macagnan; Krieger, Marco Aurélio

    2013-01-01

    The protozoan parasite Trypanosoma cruzi displays similarities to fungi in terms of its sterol lipid biosynthesis, as ergosterol and other 24-alkylated sterols are its principal endogenous sterols. The sterol pathway is thus a potential drug target for the treatment of Chagas disease. We describe here a comparative study of the growth inhibition, ultrastructural and physiological changes leading to the death of T. cruzi cells following treatment with the sterol biosynthesis inhibitors (SBIs) ...

  11. Serine biosynthesis and transport defects.

    Science.gov (United States)

    El-Hattab, Ayman W

    2016-07-01

    l-serine is a non-essential amino acid that is biosynthesized via the enzymes phosphoglycerate dehydrogenase (PGDH), phosphoserine aminotransferase (PSAT), and phosphoserine phosphatase (PSP). Besides its role in protein synthesis, l-serine is a potent neurotrophic factor and a precursor of a number of essential compounds including phosphatidylserine, sphingomyelin, glycine, and d-serine. Serine biosynthesis defects result from impairments of PGDH, PSAT, or PSP leading to systemic serine deficiency. Serine biosynthesis defects present in a broad phenotypic spectrum that includes, at the severe end, Neu-Laxova syndrome, a lethal multiple congenital anomaly disease, intermediately, infantile serine biosynthesis defects with severe neurological manifestations and growth deficiency, and at the mild end, the childhood disease with intellectual disability. A serine transport defect resulting from deficiency of the ASCT1, the main transporter for serine in the central nervous system, has been recently described in children with neurological manifestations that overlap with those observed in serine biosynthesis defects. l-serine therapy may be beneficial in preventing or ameliorating symptoms in serine biosynthesis and transport defects, if started before neurological damage occurs. Herein, we review serine metabolism and transport, the clinical, biochemical, and molecular aspects of serine biosynthesis and transport defects, the mechanisms of these diseases, and the potential role of serine therapy. PMID:27161889

  12. BIOSYNTHESIS OF STRESS ETHYLENE IN SOYBEAN SEEDLINGS: SIMILARITIES TO ENDOGENOUS ETHYLENE BIOSYNTHESIS

    Science.gov (United States)

    The similarity of stress ethylene biosynthesis in whole plants to endogenous ethylene biosynthesis was investigated using two inhibitors of ethylene biosynthesis, amino-ethoxyvinylglycine (AVG) and cobalt chloride (Co2+); and the intermediates, methionine, S-adenosylmethionine (S...

  13. Monomethylarsonous acid inhibited endogenous cholesterol biosynthesis in human skin fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Lei [Environmental Toxicology Graduate Program, University of California, Riverside, CA 92521-0403 (United States); Xiao, Yongsheng [Department of Chemistry, University of California, Riverside, CA 92521-0403 (United States); Wang, Yinsheng, E-mail: yinsheng.wang@ucr.edu [Environmental Toxicology Graduate Program, University of California, Riverside, CA 92521-0403 (United States); Department of Chemistry, University of California, Riverside, CA 92521-0403 (United States)

    2014-05-15

    Human exposure to arsenic in drinking water is a widespread public health concern, and such exposure is known to be associated with many human diseases. The detailed molecular mechanisms about how arsenic species contribute to the adverse human health effects, however, remain incompletely understood. Monomethylarsonous acid [MMA(III)] is a highly toxic and stable metabolite of inorganic arsenic. To exploit the mechanisms through which MMA(III) exerts its cytotoxic effect, we adopted a quantitative proteomic approach, by coupling stable isotope labeling by amino acids in cell culture (SILAC) with LC-MS/MS analysis, to examine the variation in the entire proteome of GM00637 human skin fibroblasts following acute MMA(III) exposure. Among the ∼ 6500 unique proteins quantified, ∼ 300 displayed significant changes in expression after exposure with 2 μM MMA(III) for 24 h. Subsequent analysis revealed the perturbation of de novo cholesterol biosynthesis, selenoprotein synthesis and Nrf2 pathways evoked by MMA(III) exposure. Particularly, MMA(III) treatment resulted in considerable down-regulation of several enzymes involved in cholesterol biosynthesis. In addition, real-time PCR analysis showed reduced mRNA levels of select genes in this pathway. Furthermore, MMA(III) exposure contributed to a distinct decline in cellular cholesterol content and significant growth inhibition of multiple cell lines, both of which could be restored by supplementation of cholesterol to the culture media. Collectively, the present study demonstrated that the cytotoxicity of MMA(III) may arise, at least in part, from the down-regulation of cholesterol biosynthesis enzymes and the resultant decrease of cellular cholesterol content. - Highlights: • MMA(III)-induced perturbation of the entire proteome of GM00637 cells is studied. • Quantitative proteomic approach revealed alterations of multiple cellular pathways. • MMA(III) inhibits de novo cholesterol biosynthesis. • MMA

  14. Monomethylarsonous acid inhibited endogenous cholesterol biosynthesis in human skin fibroblasts

    International Nuclear Information System (INIS)

    Human exposure to arsenic in drinking water is a widespread public health concern, and such exposure is known to be associated with many human diseases. The detailed molecular mechanisms about how arsenic species contribute to the adverse human health effects, however, remain incompletely understood. Monomethylarsonous acid [MMA(III)] is a highly toxic and stable metabolite of inorganic arsenic. To exploit the mechanisms through which MMA(III) exerts its cytotoxic effect, we adopted a quantitative proteomic approach, by coupling stable isotope labeling by amino acids in cell culture (SILAC) with LC-MS/MS analysis, to examine the variation in the entire proteome of GM00637 human skin fibroblasts following acute MMA(III) exposure. Among the ∼ 6500 unique proteins quantified, ∼ 300 displayed significant changes in expression after exposure with 2 μM MMA(III) for 24 h. Subsequent analysis revealed the perturbation of de novo cholesterol biosynthesis, selenoprotein synthesis and Nrf2 pathways evoked by MMA(III) exposure. Particularly, MMA(III) treatment resulted in considerable down-regulation of several enzymes involved in cholesterol biosynthesis. In addition, real-time PCR analysis showed reduced mRNA levels of select genes in this pathway. Furthermore, MMA(III) exposure contributed to a distinct decline in cellular cholesterol content and significant growth inhibition of multiple cell lines, both of which could be restored by supplementation of cholesterol to the culture media. Collectively, the present study demonstrated that the cytotoxicity of MMA(III) may arise, at least in part, from the down-regulation of cholesterol biosynthesis enzymes and the resultant decrease of cellular cholesterol content. - Highlights: • MMA(III)-induced perturbation of the entire proteome of GM00637 cells is studied. • Quantitative proteomic approach revealed alterations of multiple cellular pathways. • MMA(III) inhibits de novo cholesterol biosynthesis. • MMA

  15. Putative Genes Involved in Saikosaponin Biosynthesis in Bupleurum Species

    OpenAIRE

    Shu-Jiau Chiou; Tsai-Yun Lin; Chung-Yi Chiou

    2013-01-01

    Alternative medicinal agents, such as the herb Bupleurum, are increasingly used in modern medicine to supplement synthetic drugs. First, we present a review of the currently known effects of triterpene saponins-saikosaponins of Bupleurum species. The putative biosynthetic pathway of saikosaponins in Bupleurum species is summarized, followed by discussions on identification and characterization of genes involved in the biosynthesis of saikosaponins. The purpose is to provide a brief review of ...

  16. Improving penicillin biosynthesis in Penicillium chrysogenum by glyoxalase overproduction

    OpenAIRE

    Scheckhuber, Christian Q.; Veenhuis, Marten; van der Klei, Ida J

    2013-01-01

    Genetic engineering of fungal cell factories mainly focuses on manipulating enzymes of the product pathway or primary metabolism. However, despite the use of strong promoters or strains containing the genes of interest in multiple copies, the desired strongly enhanced enzyme levels are often not obtained. Here we present a novel strategy to improve penicillin biosynthesis by Penicillium chrysogenum by reducing reactive and toxic metabolic by-products, 2-oxoaldehydes. This was achieved by over...

  17. Initiation of methylglucose lipopolysaccharide biosynthesis in mycobacteria.

    Directory of Open Access Journals (Sweden)

    Devinder Kaur

    Full Text Available BACKGROUND: Mycobacteria produce two unique families of cytoplasmic polymethylated polysaccharides -- the methylglucose lipopolysaccharides (MGLPs and the methylmannose polysaccharides (MMPs -- the physiological functions of which are still poorly defined. Towards defining the roles of these polysaccharides in mycobacterial physiology, we generated knock-out mutations of genes in their putative biosynthetic pathways. METHODOLOGY/PRINCIPAL FINDINGS: We report here on the characterization of the Rv1208 protein of Mycobacterium tuberculosis and its ortholog in Mycobacterium smegmatis (MSMEG_5084 as the enzymes responsible for the transfer of the first glucose residue of MGLPs. Disruption of MSMEG_5084 in M. smegmatis resulted in a dramatic decrease in MGLP synthesis directly attributable to the almost complete abolition of glucosyl-3-phosphoglycerate synthase activity in this strain. Synthesis of MGLPs in the mutant was restored upon complementation with wild-type copies of the Rv1208 gene from M. tuberculosis or MSMEG_5084 from M. smegmatis. CONCLUSIONS/SIGNIFICANCE: This is the first evidence linking Rv1208 to MGLP biosynthesis. Thus, the first step in the initiation of MGLP biosynthesis in mycobacteria has been defined, and subsequent steps can be inferred.

  18. Essences in Metabolic Engineering of Lignan Biosynthesis

    Directory of Open Access Journals (Sweden)

    Honoo Satake

    2015-05-01

    Full Text Available Lignans are structurally and functionally diverse phytochemicals biosynthesized in diverse plant species and have received wide attentions as leading compounds of novel drugs for tumor treatment and healthy diets to reduce of the risks of lifestyle-related non-communicable diseases. However, the lineage-specific distribution and the low-amount of production in natural plants, some of which are endangered species, hinder the efficient and stable production of beneficial lignans. Accordingly, the development of new procedures for lignan production is of keen interest. Recent marked advances in the molecular and functional characterization of lignan biosynthetic enzymes and endogenous and exogenous factors for lignan biosynthesis have suggested new methods for the metabolic engineering of lignan biosynthesis cascades leading to the efficient, sustainable, and stable lignan production in plants, including plant cell/organ cultures. Optimization of light conditions, utilization of a wide range of elicitor treatments, and construction of transiently gene-transfected or transgenic lignan-biosynthesizing plants are mainly being attempted. This review will present the basic and latest knowledge regarding metabolic engineering of lignans based on their biosynthetic pathways and biological activities, and the perspectives in lignan production via metabolic engineering.

  19. Glycolipid biosynthesis in cyanobacteria

    International Nuclear Information System (INIS)

    The biosynthesis of monogalactosyldiacyl-glycerol (MGDG) was studied in five different cyanobacteria. Previous work has shown Anabaena variabilis to synthesize both MGDG and monoglucosyl-diacylglycerol (MG1cDG) with MG1cDG being the precursor of MGDG. They have examined four other cyanobacteria to determine if a similar relationship exists. The cyanobacteria studied were Anabaena variabilis, Chlorogloeopsis sp., Schizothrix calcicola, Anacystis nidulans, and Anacystis marina. Each were grown in liquid culture and lipids were labeled with 14C]CO2 for 20 min., 1.0 hr, 1.0 hr + 10 hr chase. Glycolipids were analyzed by initial separation of MGDG and MG1cDG by TLC followed by further analysis by HPLC. Complete separation of molecular species was obtained isocratically on an ODS column. All of the cyanobacteria labeled 16-C and 18-C fatty acids except for A. marina which labeled only 14-C and 16-C fatty acids. Desaturation of the fatty acids could be observed in the 1.0 hr and chase experiments. All were capable of labeling both MG1cDG and MGDG with the precursor-product relationship being observed. There does not appear to be a direct relationship between the epimerization of the sugar moiety and fatty acid desaturation

  20. Engineering of Glucosinolate Biosynthesis

    DEFF Research Database (Denmark)

    Møldrup, Morten Emil; Salomonsen, Bo; Halkier, Barbara Ann

    2012-01-01

    -efficient methods for identification and validation of candidate genes are needed. This chapter covers the methodology we are using for gene discovery in glucosinolate engineering, namely, guilt-by-association-based in silico methods and fast proof-of-function screens by transient expression in Nicotiana...... here will be beneficial to elucidate and engineer other plant biosynthetic pathways....