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https://www.readbyqxmd.com/read/28546842/opportunities-and-challenges-for-the-sustainable-production-of-structurally-complex-diterpenoids-in-recombinant-microbial-systems
#1
REVIEW
Katarina Kemper, Max Hirte, Markus Reinbold, Monika Fuchs, Thomas Brück
With over 50.000 identified compounds terpenes are the largest and most structurally diverse group of natural products. They are ubiquitous in bacteria, plants, animals and fungi, conducting several biological functions such as cell wall components or defense mechanisms. Industrial applications entail among others pharmaceuticals, food additives, vitamins, fragrances, fuels and fuel additives. Central building blocks of all terpenes are the isoprenoid compounds isopentenyl diphosphate and dimethylallyl diphosphate...
2017: Beilstein Journal of Organic Chemistry
https://www.readbyqxmd.com/read/28543918/gut-microbiota-of-the-pine-weevil-degrades-conifer-diterpenes-and-increases-insect-fitness
#2
Aileen Berasategui, Hassan Salem, Christian Paetz, Maricel Santoro, Jonathan Gershenzon, Martin Kaltenpoth, Axel Schmdit
The pine weevil (Hylobius abietis), a major pest of conifer forests throughout Europe, feeds on the bark and cambium, tissues rich in terpenoid resins that are toxic to many insect herbivores. Here we report the ability of the pine weevil gut microbiota to degrade the diterpene acids of Norway spruce. The diterpene acid levels present in ingested bark were substantially reduced on passage through the pine weevil gut. This reduction was significantly less upon antibiotic treatment, and supplementing the diet with gut suspensions from untreated insects restored the ability to degrade diterpenes...
May 21, 2017: Molecular Ecology
https://www.readbyqxmd.com/read/28543133/defense-syndromes-in-lodgepole-whitebark-pine-ecosystems-relate-to-degree-of-historical-exposure-to-mountain-pine-beetles
#3
Kenneth F Raffa, Charles J Mason, Pieruluigi Bonello, Stephen Cook, Nadir Erbilgin, Ken Keefover-Ring, Jennifer G Klutsch, Caterina Villari, Philip A Townsend
Warming climate is allowing tree-killing bark beetles to expand their ranges and access naïve and semi-naïve conifers. Conifers respond to attack using complex mixtures of chemical defenses that can impede beetle success, but beetles exploit some compounds for host location and communication. Outcomes of changing relationships will depend on concentrations and compositions of multiple host compounds, which are largely unknown. We analyzed constitutive and induced chemistries of Dendroctonus ponderosae's primary historical host, Pinus contorta, and P...
May 24, 2017: Plant, Cell & Environment
https://www.readbyqxmd.com/read/28539719/ultrasound-assisted-extraction-of-ursolic-acid-from-the-flowers-of-ixora-coccinia-linn-rubiaceae-and-antiproliferative-activity-of-ursolic-acid-and-synthesized-derivatives
#4
Silvana Amadeu Ferreira Alves Monteath, Maria Aparecida M Maciel, Raquel Garcia Vega, Heloisa de Mello, Carollina de Araújo Martins, Andressa Esteves-Souza, Cerli Rocha Gattass, Aurea Echevarria
BACKGROUND: Ixora coccinea Linn (Rubiaceae) is an evergreen shrub with bright scarlet colored flowers found in several tropical and subtropical countries. It is used as an ornamental and medicinal plant. Phytochemical studies revealed that its major special metabolites are triterpene acids, such as ursolic and oleanolic acid. OBJECTIVE: To evaluate the isolation of ursolic acid (UA) (1) from methanol extracts of I. coccinea flowers through two methodologies, to prepare four derivatives, and to evaluate the cytotoxic effect against six cancer cell lines...
April 2017: Pharmacognosy Magazine
https://www.readbyqxmd.com/read/28538692/exploring-anti-prion-glyco-based-and-aromatic-scaffolds-a-chemical-strategy-for-the-quality-of-life
#5
REVIEW
María Teresa Blázquez-Sánchez, Ana M de Matos, Amélia P Rauter
Prion diseases are fatal neurodegenerative disorders caused by protein misfolding and aggregation, affecting the brain progressively and consequently the quality of life. Alzheimer's is also a protein misfolding disease, causing dementia in over 40 million people worldwide. There are no therapeutics able to cure these diseases. Cellular prion protein is a high-affinity binding partner of amyloid β (Aβ) oligomers, the most toxic species in Alzheimer's pathology. These findings motivate the development of new chemicals for a better understanding of the events involved...
May 24, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28537253/a-synthetic-biochemistry-platform-for-cell-free-production-of-monoterpenes-from-glucose
#6
Tyler P Korman, Paul H Opgenorth, James U Bowie
Cell-free systems designed to perform complex chemical conversions of biomass to biofuels or commodity chemicals are emerging as promising alternatives to the metabolic engineering of living cells. Here we design a system comprises 27 enzymes for the conversion of glucose into monoterpenes that generates both NAD(P)H and ATP in a modified glucose breakdown module and utilizes both cofactors for building terpenes. Different monoterpenes are produced in our system by changing the terpene synthase enzyme. The system is stable for the production of limonene, pinene and sabinene, and can operate continuously for at least 5 days from a single addition of glucose...
May 24, 2017: Nature Communications
https://www.readbyqxmd.com/read/28535590/emission-of-volatile-organic-compounds-and-production-of-secondary-organic-aerosol-from-stir-frying-spices
#7
Tengyu Liu, Qianyun Liu, Zijun Li, Lei Huo, ManNin Chan, Xue Li, Zhen Zhou, Chak K Chan
Cooking is an important source of volatile organic compounds (VOCs) and a potential source of secondary organic aerosol (SOA) both indoors and outdoors. In this study, VOC emissions from heating corn oil and stir-frying spices (i.e. garlic, ginger, myrcia and zanthoxylum piperitum (Sichuan pepper)) were characterized using an on-line membrane inlet vacuum ultraviolet single-photon ionization time-of-flight mass spectrometer (VUV-SPI-TOFMS). VOC emissions from heating corn oil were dominated by aldehydes, which were enhanced by factors of one order of magnitude when stir-frying spices...
May 19, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28526743/systematic-identification-of-functional-residues-of-artemisia-annua-amorpha-4-11-diene-synthase
#8
Xin Fang, Jian-Xu Li, Jin-Quan Huang, You-Li Xiao, Peng Zhang, Xiao-Ya Chen
Terpene synthases (TPSs) are responsible for the extremely diversified and complex structure of terpenoids. Amorpha-4,11-diene synthase (ADS) has a high (90%) fidelity in generating the sesquiterpene precursor for biosynthesis of artemisinin, an antimalarial drug, however, little is known about how active site residues of ADS involved in the carbocation rearrangement and cyclization reactions. Here, we identify seven residues that are key to most of the catalytic steps in ADS. By structural modeling and amino acid sequence alignments of ADS with two functionally relevant sesquiterpene synthases from Artemisia annua, we performed site-directed mutagenesis and found that a single substitution, T296V, impaired the ring closure activity almost completely, and tetra-substitutions (L374Y/L404V/L405I/G439S) led to an enzyme generating 80% monocyclic bisabolyl-type sesquiterpenes, whereas a double mutant (T399L/T447G) showed compromised activity in regioselective deprotonation to yield 34...
May 19, 2017: Biochemical Journal
https://www.readbyqxmd.com/read/28523824/laser-desorption-ionisation-mass-spectrometry-imaging-of-european-yew-taxus-baccata-on-gold-nanoparticle-enhanced-target
#9
Adrian Arendowski, Tomasz Ruman
INTRODUCTION: European yew (Taxus baccata) is a plant known to man for centuries as it produces many interesting and important metabolites. These chemical compounds were repeatedly analysed by various analytical techniques, but none of the methods used so far allowed the localisation of the chemical compounds within the tissue and also correlation between plant morphology and its biochemistry. OBJECTIVE: Visualisation of the spatial distribution of yew metabolites with nanoparticle-based mass spectrometry imaging...
May 19, 2017: Phytochemical Analysis: PCA
https://www.readbyqxmd.com/read/28514947/enhanced-chlorhexidine-skin-penetration-with-1-8-cineole
#10
A L Casey, T J Karpanen, B R Conway, T Worthington, P Nightingale, R Waters, T S J Elliott
BACKGROUND: Chlorhexidine (CHG) penetrates poorly into skin. The purpose of this study was to compare the depth of CHG skin permeation from solutions containing either 2% (w/v) CHG and 70% (v/v) isopropyl alcohol (IPA) or 2% (w/v) CHG, 70% (v/v) IPA and 2% (v/v) 1,8-cineole. METHODS: An ex-vivo study using Franz diffusion cells was carried out. Full thickness human skin was mounted onto the cells and a CHG solution, with or without 2% (v/v) 1,8-cineole was applied to the skin surface...
May 17, 2017: BMC Infectious Diseases
https://www.readbyqxmd.com/read/28500552/adsorption-of-terpenic-compounds-onto-organo-palygorskite
#11
Sana Ghrab, Mabrouk Eloussaief, Stéphanie Lambert, Samir Bouaziz, Mourad Benzina
Essential oils from aromatic plants are currently mentioned as suitable tools for excellent protection of stored grains from insect pest attacks. The present work aimed to study the processes of the synthesis insecticidal formulation with clay. The active terpenic compounds of essential oil of Eucalyptus globulus (Eg) were fixed in the palygorskite by adsorption process. Two sample types of palygorskites were used: raw and organo-palygorskite. The palygorskite clays were characterized by different physicochemical techniques including X-ray diffraction (XRD), Fourier transform infrared (FTIR) analyses, thermogravimetric analysis (TG), differential thermal analysis (DTA), Brunauer-Emmet-Teller (BET), and scanning electron microscope (SEM)...
May 13, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28497050/the-role-of-biologically-active-ingredients-from-natural-drug-treatments-for-arrhythmias-in-different-mechanisms
#12
REVIEW
Jie Li, Dan Hu, Xiaoli Song, Tao Han, Yonghong Gao, Yanwei Xing
Arrhythmia is a disease that is caused by abnormal electrical activity in the heart rate or rhythm. It is the major cause of cardiovascular morbidity and mortality. Although several antiarrhythmic drugs have been used in clinic for decades, their application is often limited by their adverse effects. As a result, natural drugs, which have fewer side effects, are now being used to treat arrhythmias. We searched for all articles on the role of biologically active ingredients from natural drug treatments for arrhythmias in different mechanisms in PubMed...
2017: BioMed Research International
https://www.readbyqxmd.com/read/28495764/draft-genome-sequence-of-geobacillus-sp-lemmy01-a-thermophilic-bacterium-isolated-from-the-site-of-a-burning-grass-pile
#13
Yuri Pinheiro Alves de Souza, Fábio Faria da Mota, Alexandre Soares Rosado
We report here the 3,586,065-bp draft genome of Geobacillus sp. LEMMY01, which was isolated (axenic culture) from a thermophilic chemolitoautotrophic consortium obtained from the site of a burning grass pile. The genome contains biosynthetic gene clusters coding for secondary metabolites, such as terpene and lantipeptide, confirming the biotechnological potential of this strain.
May 11, 2017: Genome Announcements
https://www.readbyqxmd.com/read/28494107/recommendation-to-test-limonene-hydroperoxides-0-3-and-linalool-hydroperoxides-1-0-in-the-british-baseline-patch-test-series
#14
C Wlodek, C M Penfold, J F Bourke, M M U Chowdhury, S M Cooper, S Ghaffar, C Green, C R Holden, G A Johnston, A A Mughal, C Reckling, R A Sabroe, N M Stone, D Thompson, S M Wilkinson, D A Buckley
BACKGROUND: There is a significant rate of sensitisation worldwide to the oxidised fragrance terpenes limonene and linalool. Patch testing to oxidised terpenes is not routinely carried out; the ideal patch test concentration is unknown. OBJECTIVES: To determine the best test concentrations for limonene and linalool hydroperoxides, added to the British baseline patch test series, to optimise detection of true allergy and minimise irritant reactions. METHODS: During 2013-2014, 4563 consecutive patients in 12 UK centres were tested to hydroperoxides of limonene in petrolatum (pet...
May 11, 2017: British Journal of Dermatology
https://www.readbyqxmd.com/read/28493625/significant-oh-production-under-surface-cleaning-and-air-cleaning-conditions-impact-on-indoor-air-quality
#15
Nicola Carslaw, Louise Fletcher, Dwayne Heard, Trevor Ingham, Hannah Walker
We report measurements of hydroxyl (OH) and hydroperoxy (HO2 ) radicals made by laser-induced fluorescence spectroscopy in a computer classroom (i) in the absence of indoor activities (ii) during desk cleaning with a limonene-containing cleaner (iii) during operation of a commercially available 'air cleaning' device. In the unmanipulated environment, the one-minute averaged OH concentration remained close to or below the limit of detection (6.5 x 10(5) molecule cm(-3) ), whilst that of HO2 was 1.3 x 10(7) molecule cm(-3) ...
May 11, 2017: Indoor Air
https://www.readbyqxmd.com/read/28487717/identification-of-a-novel-5-epieremophilene-synthase-from-salvia-miltiorrhiza-via-transcriptome-mining
#16
Xin Fang, Chen-Yi Li, Yue Yang, Meng-Ying Cui, Xiao-Ya Chen, Lei Yang
Salvia miltiorrhiza, a medicinal plant in China, has been used for thousands of years to treat coronary heart diseases. Although biosynthesis of tanshinones, a group of diterpenoids in S. miltiorrhiza, has been extensively investigated, to date we know little about the formation of monoterpenes and sesquiterpenes in this medicinal plant. Here, we report the characterization of three sesquiterpene synthases, named SmSTPS1, SmSTPS2, and SmSTPS3, which catalyzed the formation of a new compound, (-)-5-epieremophilene...
2017: Frontiers in Plant Science
https://www.readbyqxmd.com/read/28486689/the-phytoclust-tool-for-metabolic-gene-clusters-discovery-in-plant-genomes
#17
Nadine Töpfer, Lisa-Maria Fuchs, Asaph Aharoni
The existence of Metabolic Gene Clusters (MGCs) in plant genomes has recently raised increased interest. Thus far, MGCs were commonly identified for pathways of specialized metabolism, mostly those associated with terpene type products. For efficient identification of novel MGCs, computational approaches are essential. Here, we present PhytoClust; a tool for the detection of candidate MGCs in plant genomes. The algorithm employs a collection of enzyme families related to plant specialized metabolism, translated into hidden Markov models, to mine given genome sequences for physically co-localized metabolic enzymes...
May 9, 2017: Nucleic Acids Research
https://www.readbyqxmd.com/read/28486416/transcriptomics-and-the-mediterranean-diet-a-systematic-review
#18
REVIEW
Luis V Herrera-Marcos, José M Lou-Bonafonte, Carmen Arnal, María A Navarro, Jesús Osada
The Mediterranean diet has been proven to be highly effective in the prevention of cardiovascular diseases and cancer and in decreasing overall mortality. Nowadays, transcriptomics is gaining particular relevance due to the existence of non-coding RNAs capable of regulating many biological processes. The present work describes a systematic review of current evidence supporting the influence of the Mediterranean diet on transcriptomes of different tissues in various experimental models. While information on regulatory RNA is very limited, they seem to contribute to the effect...
May 9, 2017: Nutrients
https://www.readbyqxmd.com/read/28484475/de-novo-sequencing-and-transcriptome-analysis-reveal-key-genes-regulating-steroid-metabolism-in-leaves-roots-adventitious-roots-and-calli-of-periploca-sepium-bunge
#19
Jian Zhang, Xinglin Li, Fuping Lu, Shanying Wang, Yunhe An, Xiaoxing Su, Xiankuan Li, Lin Ma, Guangjian Han
Periploca sepium Bunge is a traditional medicinal plant, whose root bark is important for Chinese herbal medicine. Its major bioactive compounds are C21 steroids and periplocin, a kind of cardiac glycoside, which are derived from the steroid synthesis pathway. However, research on P. sepium genome or transcriptomes and their related genes has been lacking for a long time. In this study we estimated this species nuclear genome size at 170 Mb (using flow cytometry). Then, RNA sequencing of four different tissue samples of P...
2017: Frontiers in Plant Science
https://www.readbyqxmd.com/read/28483880/the-c-domain-of-oleuropein-%C3%AE-glucosidase-assists-in-protein-folding-and-sequesters-the-enzyme-in-nucleus
#20
Konstantinos Koudounas, Margarita Thomopoulou, Christos Michaelidis, Efstathia Zevgiti, Georgios Papakostas, Paraskevi Tserou, Gerasimos Daras, Polydefkis Hatzopoulos
Oleuropein, a terpene-derived glycosylated secoiridoid biosynthesized exclusively by members of the Oleaceae family, is involved in a two-component defense system comprising a β-glucosidase that activates oleuropein into a toxic glutaraldehyde-like structure. Oleuropein and its deglycosylated derivatives have high pharmaceutical interest. In the present study we determined that the in planta heterologous expressed OeGLU, an oleuropein-specific β-glucosidase from olive (Olea europaea) had enzymatic kinetics similar to the olive native enzyme...
May 8, 2017: Plant Physiology
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