The Differential Expression of Mevalonate Pathway Genes in the Gut of the Bark Beetle Dendroctonus rhizophagus (Curculionidae: Scolytinae) Is Unrelated to the de Novo Synthesis of Terpenoid Pheromones

Bark beetles commonly produce de novo terpenoid pheromones using precursors synthesized through the mevalonate pathway. This process is regulated by Juvenile Hormone III (JH III). In this work, the expression levels of mevalonate pathway genes were quantified after phloem feeding—to induce the endogenous synthesis of JH III—and after the topical application of a JH III solution. The mevalonate pathway genes from D. rhizophagus were cloned, molecularly characterized, and their expression levels were quantified. Also, the terpenoid compounds produced in the gut were identified and quantified by Gas Chromatography Mass Spectrometry (GC-MS). The feeding treatment produced an evident upregulation, mainly in acetoacetyl-CoA thiolase (AACT), 3-hydroxy-3-methylglutaryl-CoA synthase (HMGS), 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR), phosphomevalonate kinase (PMK), and isopentenyl diphosphate isomerase (IPPI) genes, and males reached higher expression levels compared to females. In contrast, the JH III treatment did not present a clear pattern of upregulation in any sex or time. Notably, the genes responsible for the synthesis of frontalin and ipsdienol precursors (geranyl diphosphate synthase/farnesyl diphosphate synthase (GPPS/FPPS) and geranylgeranyl diphosphate synthase (GGPPS)) were not clearly upregulated, nor were these compounds further identified. Furthermore, trans-verbenol and myrtenol were the most abundant compounds in the gut, which are derived from an α-pinene transformation rather than de novo synthesis. Hence, the expression of mevalonate pathway genes in D. rhizophagus gut is not directed to the production of terpenoid pheromones, regardless of their frequent occurrence in the genus Dendroctonus.

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Improved cis-Abienol production through increasing precursor supply in Escherichia coli

Scientific Reports ◽

10.1038/s41598-020-73934-z ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Tao Cheng ◽

Guang Zhao ◽

Mo Xian ◽

Congxia Xie

Keyword(s):

De Novo ◽

Mevalonate Pathway ◽

High Cell Density ◽

Abies Balsamea ◽

Cell Factory ◽

Geranylgeranyl Diphosphate Synthase ◽

Geranyl Diphosphate ◽

E Coli ◽

Geranyl Diphosphate Synthase ◽

Coa Reductase

Abstract cis-Abienol, a natural diterpene-diol isolated from balsam fir (Abies balsamea), can be employed as precursors for the semi-synthesis of amber compounds, which are sustainable replacement for ambergris and widely used in the fragmented industry. This study combinatorially co-expressed geranyl diphosphate synthase, geranylgeranyl diphosphate synthase, Labda-13-en-8-ol diphosphate synthase and diterpene synthase, with the best combination achieving ~ 0.3 mg/L of cis-abienol. An additional enhancement of cis-abienol production (up to 8.6 mg/L) was achieved by introducing an exogenous mevalonate pathway which was divided into the upper pathway containing acetyl-CoA acetyltransferase/HMG-CoA reductase and HMG-CoA synthase and the lower pathway containing mevalonate kinase, phosphomevalonate kinase, pyrophosphate mevalonate decarboxylase and isopentenyl pyrophosphate isomerase. The genetically modified strain carrying chromosomal copy of low genes of the mevalonate with the trc promoter accumulated cis-abienol up to 9.2 mg/L in shake flask. Finally, cis-abienol titers of ~ 220 mg/L could be achieved directly from glucose using this de novo cis-abienol-producing E. coli in high-cell-density fermentation. This study demonstrates a microbial process to apply the E. coli cell factory in the biosynthesis of cis-abienol.

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De Novo Synthesis of 4,5-Dimethoxycatechol and 2,5-Dimethoxyhydroquinone by the Brown Rot FungusGloeophyllum trabeum

Applied and Environmental Microbiology ◽

10.1128/aem.65.2.674-679.1999 ◽

1999 ◽

Vol 65 (2) ◽

pp. 674-679 ◽

Cited By ~ 98

Author(s):

Andrzej Paszczynski ◽

Ronald Crawford ◽

David Funk ◽

Barry Goodell

Keyword(s):

Mass Spectrometry ◽

Methylene Chloride ◽

De Novo ◽

Brown Rot ◽

Gas Chromatography Mass Spectrometry ◽

Gloeophyllum Trabeum ◽

De Novo Synthesis ◽

Brown Rot Fungus ◽

Synthetic Standard ◽

Brown Rot Decay

ABSTRACT The new dimethoxycatechol 4,5-dimethoxy-1,2-benzenediol (DMC) and the new dimethoxyhydroquinone 2,5-dimethoxy-1,4-benzenediol (DMH) were isolated from stationary cultures of the brown rot fungusGloeophyllum trabeum growing on a glucose mineral medium protected from light. The structure was elucidated by gas chromatography-mass spectrometry through comparison to a synthetic standard. Further confirmation was obtained by forming a dimethoxyoxazole derivative by condensation of DMC with methylene chloride and through examination of methylated derivatives. DMC and DMH may serve as ferric chelators, oxygen-reducing agents, and redox-cycling molecules, which would include functioning as electron transport carriers to Fenton’s reactions. Thus, they appear to be important components of the brown rot decay system of the fungus.

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Comparison of Transcriptomic Profiles of MiaPaCa-2 Pancreatic Cancer Cells Treated with Different Statins

Molecules ◽

10.3390/molecules26123528 ◽

2021 ◽

Vol 26 (12) ◽

pp. 3528

Author(s):

Silvie Rimpelová ◽

Michal Kolář ◽

Hynek Strnad ◽

Tomáš Ruml ◽

Libor Vítek ◽

...

Keyword(s):

Cancer Cells ◽

Molecular Mechanisms ◽

De Novo ◽

Mevalonate Pathway ◽

Posttranslational Regulation ◽

Cycle Arrest ◽

Pancreatic Cancer Cells ◽

Expression Of Genes ◽

Beneficial Impact ◽

Coa Reductase

Statins have been widely used for the treatment of hypercholesterolemia due to their ability to inhibit HMG-CoA reductase, the rate-limiting enzyme of de novo cholesterol synthesis, via the so-called mevalonate pathway. However, their inhibitory action also causes depletion of downstream intermediates of the pathway, resulting in the pleiotropic effects of statins, including the beneficial impact in the treatment of cancer. In our study, we compared the effect of all eight existing statins on the expression of genes, the products of which are implicated in cancer inhibition and suggested the molecular mechanisms of their action in epigenetic and posttranslational regulation, and in cell-cycle arrest, death, migration, or invasion of the cancer cells.

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Inhibition of Dephosphorylation of Dolichyl Diphosphate Alters the Synthesis of Dolichol and Hinders Protein N-Glycosylation and Morphological Transitions in Candida albicans

International Journal of Molecular Sciences ◽

10.3390/ijms20205067 ◽

2019 ◽

Vol 20 (20) ◽

pp. 5067 ◽

Cited By ~ 1

Author(s):

Anna Janik ◽

Monika Niewiadomska ◽

Urszula Perlińska-Lenart ◽

Jacek Lenart ◽

Damian Kołakowski ◽

...

Keyword(s):

Candida Albicans ◽

Biofilm Formation ◽

De Novo ◽

Mevalonate Pathway ◽

Yeast Species ◽

Protein Glycosylation ◽

De Novo Synthesis ◽

Dolichyl Phosphate ◽

Morphological Transitions

The essential role of dolichyl phosphate (DolP) as a carbohydrate carrier during protein N-glycosylation is well established. The cellular pool of DolP is derived from de novo synthesis in the dolichol branch of the mevalonate pathway and from recycling of DolPP after each cycle of N-glycosylation, when the oligosaccharide is transferred from the lipid carrier to the protein and DolPP is released and then dephosphorylated. In Saccharomyces cerevisiae, the dephosphorylation of DolPP is known to be catalyzed by the Cwh8p protein. To establish the role of the Cwh8p orthologue in another distantly related yeast species, Candida albicans, we studied its mutant devoid of the CaCWH8 gene. A double Cacwh8∆/Cacwh8∆ strain was constructed by the URA-blaster method. As in S. cerevisiae, the mutant was impaired in DolPP recycling. This defect, however, was accompanied by an elevation of cis-prenyltransferase activity and higher de novo production of dolichols. Despite these compensatory changes, protein glycosylation, cell wall integrity, filamentous growth, and biofilm formation were impaired in the mutant. These results suggest that the defects are not due to the lack of DolP for the protein N-glycosylation but rather that the activity of oligosacharyltransferase could be inhibited by the excess DolPP accumulating in the mutant.

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BIOSYNTHESIS OF CONIFEROPHAGOUS BARK BEETLE PHEROMONES AND CONIFER ISOPRENOIDS: EVOLUTIONARY PERSPECTIVE AND SYNTHESIS

The Canadian Entomologist ◽

10.4039/ent132697-6 ◽

2000 ◽

Vol 132 (6) ◽

pp. 697-753 ◽

Cited By ~ 85

Author(s):

Steven J. Seybold ◽

Jörg Bohlmann ◽

Kenneth F. Raffa

Keyword(s):

Bark Beetles ◽

De Novo ◽

Scientific Paper ◽

Pheromone Biosynthesis ◽

Aggregation Pheromones ◽

Transcriptional Level ◽

Geranyl Diphosphate ◽

Biochemical Systems ◽

Vertebrate Model ◽

Monoterpene Biosynthesis

AbstractIn this overview we compare the significance and evolutionary history of two interacting biological systems, the conifer-feeding bark beetles (Coleoptera: Scolytidae) and their host conifers (Gymnospermae: Coniferales and Taxales). Isoprenoid natural products play key roles in the aggregation of the bark beetles and in the defence of the conifers. Our approach is to couple the most recent advances in the biochemical and molecular literature on these systems with ecological and behavioral data to compare monoterpenoid pheromone biosynthesis in scolytids with monoterpene biosynthesis in conifers. This synthesis reveals and evaluates the evolutionary redundancy occurring in the biochemical systems of the insect and host. Although host monoterpenes may be utilized directly or as derivatives in aggregation by scolytids, oxygenated monoterpenes that are behaviorally active for scolytids have been rarely identified from their coniferous hosts. De novo monoterpenoid biosynthesis in the Scolytidae, a process that is likely to be rare among metazoans, is substantially different from monoterpene biosynthesis in the conifers. The pathways appear to be shared only at the late-stage reactions that follow the formation of isopentenyl diphosphate. Little is known of the regulation of monoterpene biosynthesis in conifers, but scolytids positively regulate monoterpenoid biosynthesis using a sesquiterpenoid hormone, juvenile hormone, which does not occur in conifers. Little is known of the subcellular site of synthesis of monoterpenoids in scolytids, but conifer monoterpene biosynthesis is compartmentalized in the plastids, which do not occur in scolytid cells. In addition to bark beetles and conifers, the vertebrate model presents one of the few systems in which isoprenoid synthesis has been studied enough to provide a meaningful comparison. Possible unique features of monoterpenoid pheromone biosynthesis in scolytids relative to isoprenoid biosynthesis in vertebrates include the following: (1) a monoterpenoid end product; (2) a hypothetically scolytid-specific prenyl transferase (= geranyl diphosphate synthase) that catalyzes the condensation of two five-carbon (C5) units, but does not catalyze additional condensation reactions with the C5 monomelic unit; (3) a scolytid-specific monoterpene (myrcene) synthase; and (4) a scolytid-specific, transcriptional-level sesquiterpenoid isoprenoid regulatory mechanism. Features 2 and 3 may be shared with conifers. This review also updates the 1985 landmark scientific paper by John Borden by listing the references and species of coniferophagous Scolytidae for which aggregation pheromones have been identified since 1985.

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JUVENILE HORMONE REGULATES DE NOVO ISOPRENOID AGGREGATION PHEROMONE BIOSYNTHESIS IN PINE BARK BEETLES, Ips SPP., THROUGH TRANSCRIPTIONAL CONTROL OF HMG-CoA REDUCTASE

Journal of Chemical Ecology ◽

10.1007/s10886-004-7945-z ◽

2004 ◽

Vol 30 (12) ◽

pp. 2459-2494 ◽

Cited By ~ 34

Author(s):

JULIE A. TILLMAN ◽

FANG LU ◽

LANE M. GODDARD ◽

ZOE R. DONALDSON ◽

SILVER C. DWINELL ◽

...

Keyword(s):

Juvenile Hormone ◽

Aggregation Pheromone ◽

Bark Beetles ◽

Transcriptional Control ◽

De Novo ◽

Pine Bark ◽

Pheromone Biosynthesis ◽

Hmg Coa Reductase ◽

Pine Bark Beetles ◽

Coa Reductase

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Characterization of Monocyte-Associated Factor V

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649565 ◽

1993 ◽

Vol 70 (02) ◽

pp. 273-280 ◽

Cited By ~ 5

Author(s):

Janos Kappelmayer ◽

Satya P Kunapuli ◽

Edward G Wyshock ◽

Robert W Colman

Keyword(s):

Monoclonal Antibody ◽

Light Chain ◽

Peripheral Blood ◽

De Novo ◽

Factor V ◽

Blood Monocytes ◽

De Novo Synthesis ◽

Hep G2 ◽

Hep G2 Cells ◽

Peripheral Blood Monocytes

SummaryWe demonstrate that in addition to possessing binding sites for intact factor V (FV), unstimulated peripheral blood monocytes also express activated factor V (FVa) on their surfaces. FVa was identified on the monocyte surface by monoclonal antibody B38 recognizing FVa light chain and by human oligoclonal antibodies H1 (to FVa light chain) and H2 (to FVa heavy chain) using immunofluorescence microscopy and flow cytometry. On Western blots, partially cleaved FV could be identified as a 220 kDa band in lysates of monocytes. In addition to surface expression of FVa, monocytes also contain intracellular FV as detected only after permeabilization by Triton X-100 by monoclonal antibody B10 directed specifically to the Cl domain not present in FVa. We sought to determine whether the presence of FV in peripheral blood monocytes is a result of de novo synthesis.Using in situ hybridization, no FV mRNA could be detected in monocytes, while in parallel control studies, factor V mRNA was detectable in Hep G2 cells and CD18 mRNA in monocytes. In addition, using reverse transcriptase and the polymerase chain reaction, no FV mRNA was detected in mononuclear cells or in U937 cells, but mRNA for factor V was present in Hep G2 cells using the same techniques. These data suggest that FV is present in human monocytes, presumably acquired by binding of plasma FV, and that the presence of this critical coagulation factor is not due to de novo synthesis.

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Platelets Stimulate Thromboplastin Synthesis in Human Endothelial Cells

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657323 ◽

1983 ◽

Vol 49 (02) ◽

pp. 069-072 ◽

Cited By ~ 20

Author(s):

U L H Johnsen ◽

T Lyberg ◽

K S Galdal ◽

H Prydz

Keyword(s):

Endothelial Cells ◽

De Novo ◽

Umbilical Vein ◽

Time Dependent ◽

De Novo Synthesis ◽

Human Endothelial Cells ◽

Tumor Promotor ◽

Coagulation Assay ◽

Platelet Aggregates ◽

Umbilical Vein Endothelial Cells

SummaryHuman umbilical vein endothelial cells in culture synthesize thromboplastin upon stimulation with phytohaemagglutinin (PHA) or the tumor promotor 12-O-tetradecanoyl-phorbol-13-acetate (TPA). The thromboplastin activity is further strongly enhanced in a time dependent reaction by the presence of gel-filtered platelets or platelet aggregates. This effect was demonstrable at platelet concentrations lower than those normally found in plasma, it may thus be of pathophysiological relevance. The thromboplastin activity increased with increasing number of platelets added. Cycloheximide inhibited the increase, suggesting that de novo synthesis of the protein component of thromboplastin, apoprotein III, is necessary.When care was taken to remove monocytes no thromboplastin activity and no apoprotein HI antigen could be demonstrated in suspensions of gel-filtered platelets, platelets aggregated with thrombin or homogenized platelets when studied with a coagulation assay and an antibody neutralization technique.

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