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  1. Article ; Online: Reconstituting Plant Secondary Metabolism in Saccharomyces cerevisiae for Production of High-Value Benzylisoquinoline Alkaloids.

    Pyne, M E / Narcross, L / Fossati, E / Bourgeois, L / Burton, E / Gold, N D / Martin, V J J

    Methods in enzymology

    2016  Volume 575, Page(s) 195–224

    Abstract: Benzylisoquinoline alkaloids (BIAs) constitute a diverse class of plant secondary metabolites that includes the opiate analgesics morphine and codeine. Collectively, BIAs exhibit a myriad of pharmacological activities, including antimicrobial, ... ...

    Abstract Benzylisoquinoline alkaloids (BIAs) constitute a diverse class of plant secondary metabolites that includes the opiate analgesics morphine and codeine. Collectively, BIAs exhibit a myriad of pharmacological activities, including antimicrobial, antitussive, antispasmodic, and anticancer properties. Despite 2500 known BIA products, only a small proportion are currently produced though traditional crop-based manufacturing, as complex stereochemistry renders chemical synthesis of BIAs largely unfeasible. The advent of synthetic biology and sophisticated microbial engineering coupled with recent advances in the elucidation of plant BIA metabolic networks has provided growing motivation for producing high-value BIAs in microbial hosts. Here, we provide a technical basis for reconstituting BIA biosynthetic pathways in the common yeast Saccharomyces cerevisiae. Methodologies outlined in this chapter include fundamental techniques for expressing and assaying BIA biosynthetic enzymes, bioprospecting large libraries of BIA enzyme variants, and reconstituting and optimizing complete BIA formation pathways in yeast. To expedite construction of superior BIA-producing yeast strains, we emphasize high-throughput techniques. Finally, we identify fundamental challenges impeding deployment of yeast-based BIA production platforms and briefly outline future prospects to overcome such barriers.
    MeSH term(s) Benzylisoquinolines/metabolism ; Biosynthetic Pathways ; Genes, Plant ; Metabolic Engineering/methods ; Plants/enzymology ; Plants/genetics ; Plants/metabolism ; Saccharomyces cerevisiae/genetics ; Saccharomyces cerevisiae/metabolism ; Secondary Metabolism ; Synthetic Biology/methods
    Chemical Substances Benzylisoquinolines
    Language English
    Publishing date 2016
    Publishing country United States
    Document type Journal Article
    ISSN 1557-7988 ; 0076-6879
    ISSN (online) 1557-7988
    ISSN 0076-6879
    DOI 10.1016/bs.mie.2016.02.011
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  2. Article ; Online: Uptake of health monitoring and disease self-management in Australian adults with neurofibromatosis type 1: strategies to improve care.

    Crawford, H A / Barton, B / Wilson, M J / Berman, Y / McKelvey-Martin, V J / Morrison, P J / North, K N

    Clinical genetics

    2016  Volume 89, Issue 3, Page(s) 385–391

    Abstract: Lifelong health monitoring is recommended in neurofibromatosis type 1 (NF1) because of the progressive and unpredictable range of disabling and potentially life-threatening symptoms that arise. In Australia, strategies for NF1 health surveillance are ... ...

    Abstract Lifelong health monitoring is recommended in neurofibromatosis type 1 (NF1) because of the progressive and unpredictable range of disabling and potentially life-threatening symptoms that arise. In Australia, strategies for NF1 health surveillance are less well developed for adults than they are for children, resulting in inequalities between pediatric and adult care. The aims of this study were to determine the uptake of health monitoring and capacity of adults with NF1 to self-manage their health. Australian adults with NF1 (n = 94, 18-40 years) participated in a semi-structured interview. Almost half reported no regular health monitoring. Thematic analysis of interviews identified four main themes as to why: (i) did not know where to seek care, (ii) unaware of the need for regular monitoring, (iii) futility of health monitoring as nothing can be done for NF1, and (iv) feeling healthy, therefore monitoring unnecessary. Overall, there were low levels of patient activation, indicating that adults with NF1 lacked knowledge and confidence to manage their health and health care. Findings are discussed in the context of service provision for adults with NF1 in New South Wales, Australia.
    MeSH term(s) Adolescent ; Adult ; Australia ; Diagnostic Self Evaluation ; Disease Management ; Female ; Humans ; Male ; Neurofibromatosis 1/diagnosis ; Neurofibromatosis 1/therapy ; Self Care ; Surveys and Questionnaires ; Young Adult
    Language English
    Publishing date 2016-03
    Publishing country Denmark
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 221209-2
    ISSN 1399-0004 ; 0009-9163
    ISSN (online) 1399-0004
    ISSN 0009-9163
    DOI 10.1111/cge.12627
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  3. Article: Characterization of a RFamide-positive subset of ganglionic cells in the hydrozoan planular nerve net.

    Martin, V J

    Cell and tissue research

    1992  Volume 269, Issue 3, Page(s) 431–438

    Abstract: The complexity of the hydrozoan planular nervous system was examined. Using a whole-mount technique with indirect immunofluorescence, the spatial pattern of ganglionic cells showing RFamide-like immunoreactivity was visualized. RFamide antiserum bound a ... ...

    Abstract The complexity of the hydrozoan planular nervous system was examined. Using a whole-mount technique with indirect immunofluorescence, the spatial pattern of ganglionic cells showing RFamide-like immunoreactivity was visualized. RFamide antiserum bound a subset of ganglionic cells in the anterior and upper middle regions of the planula and a few ganglionic cells in the upper tail region. Labeled cells consisted of bipolar and multipolar neurons. Stained processes from these cells formed a three-dimensional nerve net that followed the contour of the mesoglea; such fibers were striking in terms of their large numbers, long lengths, and organization into distinct bundles. Labeled fibers were seen to contact other ganglionic cells, sensory cells, epithelio-muscle cells, the mesoglea, and the outside free surface. All stained cell bodies and fibers were found in the ectoderm. Using the same technique the reappearance of RFamide-positive ganglionic cells in epithelial tissue of chimeric grafts of planulae was observed. Interstitial cells capable of forming RFamide-positive ganglionic cells underwent extensive anterior-posterior migrations in the grafts, moved into the epithelial tissue, and differentiated into RFamide-positive ganglionic cells. Stained repopulated ganglionic cells always formed in the same position in the epithelial tissue as was observed in control planulae suggesting that the expression of RFamide-like substances may be position dependent in the planula.
    MeSH term(s) Animals ; Cnidaria/anatomy & histology ; Cnidaria/metabolism ; Epithelial Cells ; Epithelium/chemistry ; Female ; Ganglia/chemistry ; Ganglia/cytology ; Immune Sera ; Immunohistochemistry ; Male ; Neurons/chemistry ; Neuropeptides/analysis ; Neuropeptides/metabolism
    Chemical Substances Immune Sera ; Neuropeptides ; arginylphenylalaninamide (34388-59-5)
    Language English
    Publishing date 1992-09
    Publishing country Germany
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 125067-x
    ISSN 1432-0878 ; 0302-766X
    ISSN (online) 1432-0878
    ISSN 0302-766X
    DOI 10.1007/bf00353898
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  4. Article ; Online: Development of Nerve Cells in Hydrozoan Planulae: III. Some Interstitial Cells Traverse the Ganglionic Pathway in the Endoderm.

    Martin, V J

    The Biological bulletin

    1990  Volume 178, Issue 1, Page(s) 10–20

    Abstract: Hydrozoan planulae of Pennaria tiarella possess migratory stem cells--interstitial cells--that are capable of self renewal and can differentiate into either ganglionic nerve cells or nematocytes. The commitment and differentiation of a subpopulation of ... ...

    Abstract Hydrozoan planulae of Pennaria tiarella possess migratory stem cells--interstitial cells--that are capable of self renewal and can differentiate into either ganglionic nerve cells or nematocytes. The commitment and differentiation of a subpopulation of larval endodermal interstitial cells to the neural pathway were examined using light immunocytochemistry and transmission electron microscopy. Embryos of different ages, from 8 to 96 h, were tested for their ability to bind rabbit antiserum raised to the neuropeptide FMRFamide. A subpopulation of interstitial cells in the anterior endoderm of the planula begins to express a FMRFamide-like antigen between 48 and 72 h postfertilization. Concurrent with this endodermal interstitial cell expression, a subset of ectodermal ganglionic cells with FMRFamide-like immunoreactivity appears in the anterior end of the planula. Ultrastructural examination of the interstitial cell population in the anterior planular endoderm, at 48 h in development, indicates that, based upon morphology, there are at least three subsets of interstitial cells in this region: undifferentiated interstitial cells, interstitial cells traversing the nematocyte differentiation pathway, and interstitial cells traversing the neural differentiation pathway. The endodermal interstitial cells entering the neural pathway form a Golgi complex, electron-dense droplets, dense cored vesicles, and microtubules. Neurite formation does not occur in the endoderm; rather, neurites are only found in association with ectodermal ganglionic cells. Furthermore, planulae lack fully differentiated endodermal neurons. This study demonstrates that, during embryogenesis, some interstitial cells destined for neural differentiation are committed in the endoderm before their emigration to the ectoderm, begin to express cytochemical and morphological features of neural differentiation while in the endoderm, and migrate to the ectoderm as neuroblasts.
    Language English
    Publishing date 1990-02
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1268-3
    ISSN 1939-8697 ; 0006-3185 ; 0148-9488
    ISSN (online) 1939-8697
    ISSN 0006-3185 ; 0148-9488
    DOI 10.2307/1541532
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  5. Article: Genetic investigation of the catabolic pathway for degradation of abietane diterpenoids by Pseudomonas abietaniphila BKME-9.

    Martin, V J / Mohn, W W

    Journal of bacteriology

    2000  Volume 182, Issue 13, Page(s) 3784–3793

    Abstract: We have cloned and sequenced the dit gene cluster encoding enzymes of the catabolic pathway for abietane diterpenoid degradation by Pseudomonas abietaniphila BKME-9. The dit gene cluster is located on a 16.7-kb DNA fragment containing 13 complete open ... ...

    Abstract We have cloned and sequenced the dit gene cluster encoding enzymes of the catabolic pathway for abietane diterpenoid degradation by Pseudomonas abietaniphila BKME-9. The dit gene cluster is located on a 16.7-kb DNA fragment containing 13 complete open reading frames (ORFs) and 1 partial ORF. The genes ditA1A2A3 encode the alpha and beta subunits and the ferredoxin of the dioxygenase which hydroxylates 7-oxodehydroabietic acid to 7-oxo-11,12-dihydroxy-8, 13-abietadien acid. The dioxygenase mutant strain BKME-941 (ditA1::Tn5) did not grow on nonaromatic abietanes, and transformed palustric and abietic acids to 7-oxodehydroabietic acid in cell suspension assays. Thus, nonaromatic abietanes are aromatized prior to further degradation. Catechol 2,3-dioxygenase activity of xylE transcriptional fusion strains showed induction of ditA1 and ditA3 by abietic, dehydroabietic, and 7-oxodehydroabietic acids, which support the growth of strain BKME-9, as well as by isopimaric and 12, 14-dichlorodehydroabietic acids, which are diterpenoids that do not support the growth of strain BKME-9. In addition to the aromatic-ring-hydroxylating dioxygenase genes, the dit cluster includes ditC, encoding an extradiol ring cleavage dioxygenase, and ditR, encoding an IclR-type transcriptional regulator. Although ditR is not strictly required for the growth of strain BKME-9 on abietanes, a ditR::Km(r) mutation in a ditA3::xylE reporter strain demonstrated that it encodes an inducer-dependent transcriptional activator of ditA3. An ORF with sequence similarity to genes encoding permeases (ditE) is linked with genes involved in abietane degradation.
    MeSH term(s) Abietanes ; Bacterial Proteins ; Base Sequence ; DNA, Bacterial ; Dioxygenases ; Diterpenes/metabolism ; Ferredoxins/genetics ; Gene Expression Regulation, Bacterial ; Gene Expression Regulation, Enzymologic ; Genes, Bacterial ; Molecular Sequence Data ; Multigene Family ; Mutagenesis ; Open Reading Frames ; Oxygenases/genetics ; Phenanthrenes/metabolism ; Pseudomonas/enzymology ; Pseudomonas/genetics ; Pseudomonas/metabolism
    Chemical Substances 7-oxo-11,12-dihydroxy-8,13-abietadien acid ; Abietanes ; Bacterial Proteins ; DNA, Bacterial ; Diterpenes ; Ferredoxins ; Phenanthrenes ; Oxygenases (EC 1.13.-) ; Dioxygenases (EC 1.13.11.-) ; DitA protein, Pseudomonas abietaniphila (EC 1.13.11.-) ; 7-oxodehydroabietic acid (I8PNL8FLID)
    Language English
    Publishing date 2000-07
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2968-3
    ISSN 1098-5530 ; 0021-9193
    ISSN (online) 1098-5530
    ISSN 0021-9193
    DOI 10.1128/JB.182.13.3784-3793.2000
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  6. Article: A novel aromatic-ring-hydroxylating dioxygenase from the diterpenoid-degrading bacterium Pseudomonas abietaniphila BKME-9.

    Martin, V J / Mohn, W W

    Journal of bacteriology

    1999  Volume 181, Issue 9, Page(s) 2675–2682

    Abstract: Pseudomonas abietaniphila BKME-9 is able to degrade dehydroabietic acid (DhA) via ring hydroxylation by a novel dioxygenase. The ditA1, ditA2, and ditA3 genes, which encode the alpha and beta subunits of the oxygenase and the ferredoxin of the ... ...

    Abstract Pseudomonas abietaniphila BKME-9 is able to degrade dehydroabietic acid (DhA) via ring hydroxylation by a novel dioxygenase. The ditA1, ditA2, and ditA3 genes, which encode the alpha and beta subunits of the oxygenase and the ferredoxin of the diterpenoid dioxygenase, respectively, were isolated and sequenced. The ferredoxin gene is 9. 2 kb upstream of the oxygenase genes and 872 bp upstream of a putative meta ring cleavage dioxygenase gene, ditC. A Tn5 insertion in the alpha subunit gene, ditA1, resulted in the accumulation by the mutant strain BKME-941 of the pathway intermediate, 7-oxoDhA. Disruption of the ferredoxin gene, ditA3, in wild-type BKME-9 by mutant-allele exchange resulted in a strain (BKME-91) with a phenotype identical to that of the mutant strain BKME-941. Sequence analysis of the putative ferredoxin indicated that it is likely to be a [4Fe-4S]- or [3Fe-4S]-type ferredoxin and not a [2Fe-2S]-type ferredoxin, as found in all previously described ring-hydroxylating dioxygenases. Expression in Escherichia coli of ditA1A2A3, encoding the diterpenoid dioxygenase without its putative reductase component, resulted in a functional enzyme. The diterpenoid dioxygenase attacks 7-oxoDhA, and not DhA, at C-11 and C-12, producing 7-oxo-11, 12-dihydroxy-8,13-abietadien acid, which was identified by 1H nuclear magnetic resonance, UV-visible light, and high-resolution mass spectrometry. The organization of the genes encoding the various components of the diterpenoid dioxygenase, the phylogenetic distinctiveness of both the alpha subunit and the ferredoxin component, and the unusual Fe-S cluster of the ferredoxin all suggest that this enzyme belongs to a new class of aromatic ring-hydroxylating dioxygenases.
    MeSH term(s) Abietanes ; Amino Acid Sequence ; Bacterial Proteins ; Cloning, Molecular ; Dioxygenases ; Diterpenes/metabolism ; Ferredoxins/genetics ; Ferredoxins/metabolism ; Genes, Bacterial ; Hydroxylation ; Isoenzymes/genetics ; Isoenzymes/metabolism ; Molecular Sequence Data ; Mutagenesis, Insertional ; Oxygenases/classification ; Oxygenases/genetics ; Oxygenases/metabolism ; Phenanthrenes/metabolism ; Pseudomonas/enzymology ; Pseudomonas/genetics ; Recombinant Proteins/metabolism ; Sequence Analysis, DNA ; Sequence Homology, Amino Acid
    Chemical Substances 7-oxo-11,12-dihydroxy-8,13-abietadien acid ; 7-oxodihydroabietic acid ; Abietanes ; Bacterial Proteins ; Diterpenes ; Ferredoxins ; Isoenzymes ; Phenanthrenes ; Recombinant Proteins ; Oxygenases (EC 1.13.-) ; Dioxygenases (EC 1.13.11.-) ; DitA protein, Pseudomonas abietaniphila (EC 1.13.11.-)
    Language English
    Publishing date 1999-05
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2968-3
    ISSN 1098-5530 ; 0021-9193
    ISSN (online) 1098-5530
    ISSN 0021-9193
    DOI 10.1128/JB.181.9.2675-2682.1999
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  7. Article: An alternative inverse PCR (IPCR) method to amplify DNA sequences flanking Tn5 transposon insertions.

    Martin, V J / Mohn, W W

    Journal of microbiological methods

    1999  Volume 35, Issue 2, Page(s) 163–166

    Abstract: We have developed an alternative method to amplify DNA sequences flanking Tn5 transposon insertions. This method relies on the identical sequences of inverted terminal repeats, located at the 5' and 3' ends of Tn5, to determine the location and ... ...

    Abstract We have developed an alternative method to amplify DNA sequences flanking Tn5 transposon insertions. This method relies on the identical sequences of inverted terminal repeats, located at the 5' and 3' ends of Tn5, to determine the location and orientation of a transposon insertion within a restriction endonuclease fragment. From this information, PCR primers can be designed to selectively amplify by inverse PCR the DNA flanking one side of the transposon. This method avoids the problem of amplifying or cloning long sequences flanking Tn5. To demonstrate the applicability of this method, we generated Tn5 transposon mutants of Pseudomonas abietaniphila BKME-9 which no longer grew on dehydroabietic acid (DhA). The flanking sequence of one of the mutant (strain BKME-941) which accumulated 7-oxoDhA, was amplified.
    MeSH term(s) Blotting, Southern ; DNA Transposable Elements ; DNA, Bacterial/analysis ; DNA, Bacterial/isolation & purification ; Diterpenes/metabolism ; Diterpenes, Abietane ; Mutagenesis, Insertional ; Polymerase Chain Reaction/methods ; Pseudomonas/genetics ; Pseudomonas/growth & development
    Chemical Substances DNA Transposable Elements ; DNA, Bacterial ; Diterpenes ; Diterpenes, Abietane ; dehydroabietic acid (0S5XP6S3AU)
    Language English
    Publishing date 1999-03
    Publishing country Netherlands
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 604916-3
    ISSN 1872-8359 ; 0167-7012
    ISSN (online) 1872-8359
    ISSN 0167-7012
    DOI 10.1016/s0167-7012(98)00115-8
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  8. Article ; Online: Stages of Larval Development and Stem Cell Population Changes During Metamorphosis of a Hydrozoan Planula.

    Martin, V J / Archer, W E

    The Biological bulletin

    1997  Volume 192, Issue 1, Page(s) 41–52

    Abstract: Scanning electron microscopy and light histology were used to reveal the changes in overall morphology and in stem cell differentiation and distribution that occur as a free-swimming, solid hydrozoan planula larva is transformed into a sessile, hollow ... ...

    Abstract Scanning electron microscopy and light histology were used to reveal the changes in overall morphology and in stem cell differentiation and distribution that occur as a free-swimming, solid hydrozoan planula larva is transformed into a sessile, hollow adult polyp. Eight stages of development are described: young 10-hour planula, mature 48-hour planula, attaching planula, disc, pawn, crown, immature polyp, and primary adult polyp. The larval interstitial stem cell population (interstitial cells, nematocytes, ganglion cells) undergoes dramatic changes during metamorphosis: (1) distribution patterns change, (2) certain larval derivatives disappear, (3) new types of derivatives differentiate, and (4) migration patterns become more complex. This study is the first to examine how a stem cell system develops in an organism that goes from embryo to larva to adult.
    Language English
    Publishing date 1997-02
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1268-3
    ISSN 1939-8697 ; 0006-3185 ; 0148-9488
    ISSN (online) 1939-8697
    ISSN 0006-3185 ; 0148-9488
    DOI 10.2307/1542574
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  9. Article: The in vivo synthesis of plant sesquiterpenes by Escherichia coli.

    Martin, V J / Yoshikuni, Y / Keasling, J D

    Biotechnology and bioengineering

    2001  Volume 75, Issue 5, Page(s) 497–503

    Abstract: Three plant genes encoding (+)-delta-cadinene, 5-epi-aristolochene, and vetispiradiene cyclases were expressed in Escherichia coli to evaluate the potential of this bacterium to synthesize sesquiterpenes in vivo. Various growth temperatures, carbon ... ...

    Abstract Three plant genes encoding (+)-delta-cadinene, 5-epi-aristolochene, and vetispiradiene cyclases were expressed in Escherichia coli to evaluate the potential of this bacterium to synthesize sesquiterpenes in vivo. Various growth temperatures, carbon sources, and host strains were examined to optimize terpene production. The highest levels of sesquiterpene production occurred when the enzymes were expressed in strain DH5alpha from the trc promoter (Ptrc) of the high-copy plasmidpTrc99A in M9 medium supplemented with 0.2% (v/v) glycerol at 30 degrees C for 5-epi-aristolochene and vetispiradiene and 37 degrees C for (+)-delta-cadinene. The highest concentrations of sesquiterpenes observed were 10.3 microg of (+)-delta-cadinene, 0.24 microg of 5-epi-aristolochene (measured as (+)-delta-cadinene equivalents), and 6.4 microg of vetispiradiene (measured as (+)-delta-cadinene equivalents) per liter of culture. These sesquiterpene production levels are >500-fold lower than carotenoid production, both of which are synthesized from endogenous trans-farnesyl diphosphate (FDP) in E. coli. Based on these results, we conclude that the limiting factor for sesquiterpene synthesis in E. coli is the poor expression of the cyclase enzyme and not supply of the FDP precursor.
    MeSH term(s) Alkyl and Aryl Transferases/genetics ; Alkyl and Aryl Transferases/metabolism ; Biotechnology ; Carbon-Carbon Lyases/genetics ; Carbon-Carbon Lyases/metabolism ; Culture Media/metabolism ; Escherichia coli/genetics ; Escherichia coli/metabolism ; Gene Expression ; Genes, Plant/physiology ; Genetic Vectors/genetics ; Hydrogen-Ion Concentration ; Polyisoprenyl Phosphates/metabolism ; Sesquiterpenes/metabolism ; Temperature ; Time Factors ; Transduction, Genetic
    Chemical Substances Culture Media ; Polyisoprenyl Phosphates ; Sesquiterpenes ; farnesyl pyrophosphate (79W6B01D07) ; Alkyl and Aryl Transferases (EC 2.5.-) ; terpene carbocyclase (EC 2.5.1.-) ; Carbon-Carbon Lyases (EC 4.1.-) ; trichodiene synthetase (EC 4.2.3.6)
    Language English
    Publishing date 2001-12-05
    Publishing country United States
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 280318-5
    ISSN 1097-0290 ; 0006-3592
    ISSN (online) 1097-0290
    ISSN 0006-3592
    DOI 10.1002/bit.10037
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  10. Article: Controlling the metabolic flux through the carotenoid pathway using directed mRNA processing and stabilization.

    Smolke, C D / Martin, V J / Keasling, J D

    Metabolic engineering

    2001  Volume 3, Issue 4, Page(s) 313–321

    Abstract: A synthetic operon containing the crtI and crtY genes, encoding the phytoene desaturase and the lycopene cyclase, respectively, was placed under the control of the araBAD promoter. DNA cassettes encoding mRNA secondary structures were placed at the 5' ... ...

    Abstract A synthetic operon containing the crtI and crtY genes, encoding the phytoene desaturase and the lycopene cyclase, respectively, was placed under the control of the araBAD promoter. DNA cassettes encoding mRNA secondary structures were placed at the 5' and 3' ends of the genes and a putative RNase E site was placed between the genes. This construct was transformed into Escherichia coli cells harboring the genes for phytoene production. By varying the mRNA secondary structures, we were able to modulate the flux through the carotenoid pathway, resulting in a 300-fold variation in the production of beta-carotene relative to lycopene. In addition, intermediates in the pathway from phytoene to beta-carotene production that are not observed in cells expressing the recombinant operon were observed when the engineered operons were used, indicating that changes in levels of the enzymes affected the formation of intermediates. These results indicate that it is possible to coordinately regulate the genes encoding the enzymes of a metabolic pathway and balance the production of the intermediates.
    MeSH term(s) Carotenoids/analysis ; Carotenoids/biosynthesis ; Carotenoids/genetics ; Escherichia coli/metabolism ; Plasmids ; RNA, Messenger/metabolism
    Chemical Substances RNA, Messenger ; Carotenoids (36-88-4) ; (all-E) phytoene (87E4NJ6N51)
    Language English
    Publishing date 2001-10-17
    Publishing country Belgium
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 1470383-x
    ISSN 1096-7184 ; 1096-7176
    ISSN (online) 1096-7184
    ISSN 1096-7176
    DOI 10.1006/mben.2001.0194
    Database MEDical Literature Analysis and Retrieval System OnLINE

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