Use of control analysis to study the regulation of plant lipid biosynthesis

2002 ◽  
Vol 30 (6) ◽  
pp. 1043-1046 ◽  
Author(s):  
U. S. Ramli ◽  
D. S. Baker ◽  
P. A. Quant ◽  
J. L. Harwood
Keyword(s):  
Biosynthetic Pathway ◽  
Fatty Acid Biosynthesis ◽  
Elaeis Guineensis ◽  
Lipid Biosynthesis ◽  
Control Analysis ◽  
Experimental Conditions ◽  
Plant Lipid ◽  
Oil Crops ◽  
First Time ◽  
Single Enzyme

Control analysis is a powerful method to quantify the regulation of metabolic pathways. We have applied it to lipid biosynthesis for the first time by using model tissue culture systems from the important oil crops, olive (Olea europaea L.) and oil palm (Elaeis guineensis Jacq.). By the use of top-down control analysis, fatty acid biosynthesis has been shown to exert more control than lipid assembly under different experimental conditions. However, both parts of the lipid biosynthetic pathway are important, so that attempts to alter oil yield by manipulating the activity of a single enzyme step are very unlikely to produce significant increases.

scholarly journals Control analysis of lipid biosynthesis in tissue cultures from oil crops shows that flux control is shared between fatty acid synthesis and lipid assembly

2002 ◽  
Vol 364 (2) ◽  
pp. 393-401 ◽  
Author(s):  
Umi S. RAMLI ◽  
Darren S. BAKER ◽  
Patti A. QUANT ◽  
John L. HARWOOD
Keyword(s):  
Fatty Acid ◽  
Fatty Acid Synthesis ◽  
Oil Palm ◽  
Biosynthetic Pathway ◽  
Acid Synthesis ◽  
Lipid Biosynthesis ◽  
Control Analysis ◽  
Tissue Cultures ◽  
Flux Control ◽  
Oil Crops

Top-Down (Metabolic) Control Analysis (TDCA) was used to examine, quantitatively, lipid biosynthesis in tissue cultures from two commercially important oil crops, olive (Olea europaea L.) and oil palm (Elaeis guineensis Jacq.). A conceptually simplified system was defined comprising two blocks of reactions: fatty acid synthesis (Block A) and lipid assembly (Block B), which produced and consumed, respectively, a common and unique system intermediate, cytosolic acyl-CoA. We manipulated the steady-state levels of the system intermediate by adding exogenous oleic acid and, using two independent assays, measured the effect of the addition on the system fluxes (JA and JB). These were the rate of incorporation of radioactivity: (i) through Block A from [1-14C]acetate into fatty acids and (ii) via Block B from [U-14C]glycerol into complex lipids respectively. The data showed that fatty acid formation (Block A) exerted higher control than lipid assembly (Block B) in both tissues with the following group flux control coefficients (C):(i) Oil palm: ∗CJTLBlkB = 0.64±0.05 and ∗CJTLBlkB = 0.36±0.05(ii) Olive: ∗CJTLBlkB =0.57±0.10 and ∗CJTLBlkB = 0.43±0.10where ∗C indicates the group flux control coefficient over the lipid biosynthesis flux (JTL) and the subscripts BlkA and BlkB refer to defined blocks of the system, Block A and Block B. Nevertheless, because both parts of the lipid biosynthetic pathway exert significant flux control, we suggest strongly that manipulation of single enzyme steps will not affect product yield appreciably. The present study represents the first use of TDCA to examine the overall lipid biosynthetic pathway in any tissue, and its findings are of immediate academic and economic relevance to the yield and nutritional quality of oil crops.

scholarly journals The effect of salinity on enterocytozoon hepatopenaei infection in Penaeus vannamei under experimental conditions

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
L. F. Aranguren Caro ◽  
F. Alghamdi ◽  
K. De Belder ◽  
J. Lin ◽  
H. N. Mai ◽  
...  
Keyword(s):  
Penaeus Monodon ◽  
Oral Route ◽  
Western Hemisphere ◽  
Penaeus Vannamei ◽  
Asian Countries ◽  
Experimental Conditions ◽  
Reliable Source ◽  
Specific Pathogen ◽  
Enterocytozoon Hepatopenaei ◽  
First Time

Abstract Background Enterocytozoon hepatopenaei (EHP) is an enteric pathogen that affects Penaeus vannamei and Penaeus monodon shrimp in many SE Asian countries. In the western hemisphere, EHP was reported for the first time in 2016 in farmed P. vannamei in Venezuela. Anecdotal evidence suggests that EHP is more prevalent in grow-out ponds where the salinity is high (> 15 parts per thousand (ppt)) compared to grow-out ponds with low salinities (< 5 ppt). Considering that P. vannamei is an euryhaline species, we were interested in knowing if EHP can propagate in P. vannamei in low salinities. Results In this study, we described an experimental infection using fecal strings as a source inoculum. Specific Pathogen Free (SPF) P. vannamei were maintained at three different salinities (2 ppt, 15 ppt, and 30 ppt) while continuously challenged using feces from known EHP-infected P. vannamei over a period of 3 weeks. The fecal strings, used as a source of EHP inocula in the challenges, was sufficient to elicit an infection in shrimp maintained at the three salinities. The infectivity of EHP in shrimp reared at 2 ppt, 15 ppt, and 30 ppt salinities was confirmed by PCR and histopathology. The prevalence and the severity of the EHP infection was higher at 30 ppt than at 2 ppt and 15 ppt. Conclusion The data suggests that fecal strings are a reliable source of EHP inoculum to conduct experimental challenges via the fecal-oral route. An EHP infection can occur at a salinity as low as 2 ppt, however, the prevalence and the severity of the EHP infection is higher at a salinity of 30 ppt.

scholarly journals Comparative investigation of lasing and amplification performance in cryogenic Yb:YLF systems

2021 ◽  
Vol 127 (3) ◽  
Author(s):  
Umit Demirbas ◽  
Martin Kellert ◽  
Jelto Thesinga ◽  
Yi Hua ◽  
Simon Reuter ◽  
...  
Keyword(s):  
Continuous Wave ◽  
Estimation Method ◽  
Laser Cavity ◽  
Comparative Investigation ◽  
Limiting Factor ◽  
Experimental Conditions ◽  
Temperature Estimation ◽  
Transverse Temperature ◽  
First Time

AbstractWe present detailed experimental results with cryogenic Yb:YLF gain media in rod-geometry. We have comparatively investigated continuous-wave (cw) lasing and regenerative amplification performance under different experimental conditions. In the cw lasing experiments effect of crystal doping, cw laser cavity geometry and pump wavelength on lasing performance were explored. Regenerative amplification behavior was analyzed and the role of depolarization losses on performance was investigated. A recently developed temperature estimation method was also employed for the first time in estimating average crystal temperature under lasing conditions. It is shown that the thermal lens induced by transverse temperature gradients is the main limiting factor and strategies for future improvements are discussed. To the best of our knowledge, the achieved results in this study (375 W in cw, and 90 W in regenerative amplification) are the highest average powers ever obtained from this system via employing the broadband E//a axis.

scholarly journals Comprehensive Metabolomics Study of Traditionally Important Rumex Species Found in Western Himalayan Region

2018 ◽  
Vol 13 (2) ◽  
pp. 1934578X1801300
Author(s):  
Ritika Sharma ◽  
Rupali Jandrotia ◽  
Bikram Singh ◽  
Upendra Sharma ◽  
Dinesh Kumar
Keyword(s):  
Raw Materials ◽  
Chemical Diversity ◽  
Control Analysis ◽  
Limit Of Quantification ◽  
Western Himalayan Region ◽  
Biological Potential ◽  
Metabolomics Study ◽  
Comprehensive Metabolomics ◽  
First Time ◽  
Concurrent Estimation

Rumex species are traditionally known to cure constipation, pain, inflammation, ulcer and tumor. The biological potential of Rumex nepalens is lies in chemical diversity of its constituents. In the present study, UPLC-DAD-MS method was developed for the concurrent estimation of polyphenols in Rumex species ( R. nepalensis, R. hastatus and R. dentatus) and validated for linearity (r2 > 0.999), limit of quantification and detection, inter and intraday precession, stabilities and recovery. The developed method has also been employed for metabolomic analysis of Rumex species. Qualitative and quantitative variation of polyphenols was observed among the aerial and root parts of Rumex species with highest content of polyphenol detected in aerial part of R. nepalensis. The quantitative data based matrix and HCA plot represents the variation of metabolites among the samples. R. nepalensis being widely used in traditional practices, was incorporated in detail. A total of seven molecules were isolated and characterized among which three compounds viz. 3- O- methyl epicatechin, quercetin-3- O- β-D-glucuronide and β-sitosterol-3- O- β-D-glucoside were isolated for first time from this plant. Eighteen metabolites were profiled in R. nepalensis using UPLC-MS/MS technique. Current comprehensive metabolomics approach will surely help in understanding the chemical diversity, discriminations and quality control analysis of raw materials and furnished products of Rumex.

scholarly journals Biosynthesis of anandamide and N-palmitoylethanolamine by sequential actions of phospholipase A2 and lysophospholipase D

2004 ◽  
Vol 380 (3) ◽  
pp. 749-756 ◽  
Author(s):  
Yong-Xin SUN ◽  
Kazuhito TSUBOI ◽  
Yasuo OKAMOTO ◽  
Takeharu TONAI ◽  
Makoto MURAKAMI ◽  
...  
Keyword(s):  
Biosynthetic Pathway ◽  
Brain Homogenate ◽  
Wide Distribution ◽  
Rat Tissues ◽  
Lysophospholipase D ◽  
Pla2 Enzyme ◽  
First Time ◽  
Hydrolysis Of ◽  
The Brain

Anandamide (an endocannabinoid) and other bioactive long-chain NAEs (N-acylethanolamines) are formed by direct release from N-acyl-PE (N-acyl-phosphatidylethanolamine) by a PLD (phospholipase D). However, the possible presence of a two-step pathway from N-acyl-PE has also been suggested previously, which comprises (1) the hydrolysis of N-acyl-PE to N-acyl-lysoPE by PLA1/PLA2 enzyme(s) and (2) the release of NAEs from N-acyllysoPE by lysoPLD (lysophospholipase D) enzyme(s). In the present study we report for the first time the characterization of enzymes responsible for this pathway. The PLA1/PLA2 activity for N-palmitoyl-PE was found in various rat tissues, with the highest activity in the stomach. This stomach enzyme was identified as group IB sPLA2 (secretory PLA2), and its product was determined as N-acyl-1-acyl-lysoPE. Recombinant group IB, IIA and V of sPLA2s were also active with N-palmitoyl-PE, whereas group X sPLA2 and cytosolic PLA2α were inactive. In addition, we found wide distribution of lysoPLD activity generating N-palmitoylethanolamine from N-palmitoyl-lysoPE in rat tissues, with higher activities in the brain and testis. Based on several lines of enzymological evidence, the lysoPLD enzyme could be distinct from the known N-acyl-PE-hydrolysing PLD. sPLA2-IB dose dependently enhanced the production of N-palmitoylethanolamine from N-palmitoyl-PE in the brain homogenate showing the lysoPLD activity. N-Arachidonoyl-PE and N-arachidonoyl-lysoPE as anandamide precursors were also good substrates of sPLA2-IB and the lysoPLD respectively. These results suggest that the sequential actions of PLA2 and lysoPLD may constitute another biosynthetic pathway for NAEs, including anandamide.

scholarly journals Extrusion Processing of Amaranth and Quinoa into Gluten-Free Snack Foods for Celiac and Gluten-Free Diets

2017 ◽  
Vol 6 (5) ◽  
pp. 107
Author(s):  
Caitlin Gearhart ◽  
Kurt A. Rosentrater
Keyword(s):  
Scale Up ◽  
Food Products ◽  
Poor Quality ◽  
Expansion Ratio ◽  
Gluten Free ◽  
Experimental Conditions ◽  
Snack Foods ◽  
Extrusion Processing ◽  
Nutritional Benefits ◽  
First Time

Because of the growth of gluten intolerance and Celiac disease, there is growing interest in development of gluten-free foods. Beyond just being gluten-free, such foods can also have other positive nutritional benefits to human health. Extrusion processing is commonly used to produce a wide variety of human food products. Gluten-free grains can be a processing challenge, however, due to lack of proper binding, which can lead to poor quality food products. This research explores how extrusion parameters impacted the quality of amaranth- and quinoa-based extrudates. The specific objectives of this project included extruding each of the grains, then measuring extrudate properties, such as color, unit density, expansion ratio, and durability. Both the quinoa and amaranth were extruded as raw grain, as well as ground to 2mm and 1mm particle sizes. Other experimental conditions included moisture contents of 20% and 40% (d.b.), and extruder screw speeds of 50 rpm and 100 rpm. All treatments were successfully extruded, and all extrudates had high quality attributes, making this the first time either quinoa or amaranth was extruded without any binding ingredients. This study provides information useful for commercial scale-up.

Microarray analysis of the transcriptome of the subfornical organ in the rat: regulation by fluid and food deprivation

2008 ◽  
Vol 295 (6) ◽  
pp. R1914-R1920 ◽  
Author(s):  
Charles Hindmarch ◽  
Mark Fry ◽  
Song T. Yao ◽  
Pauline M. Smith ◽  
David Murphy ◽  
...  
Keyword(s):  
Gene Expression ◽  
Statistical Analysis ◽  
Food Deprivation ◽  
Subfornical Organ ◽  
Microarray Technology ◽  
Type B ◽  
Bdnf Expression ◽  
Experimental Conditions ◽  
Calcium Sensing ◽  
First Time

We have employed microarray technology using Affymetrix 230 2.0 genome chips to initially catalog the transcriptome of the subfornical organ (SFO) under control conditions and to also evaluate the changes (common and differential) in gene expression induced by the challenges of fluid and food deprivation. We have identified a total of 17,293 genes tagged as present in one of our three experimental conditions, transcripts, which were then used as the basis for further filtering and statistical analysis. In total, the expression of 46 genes was changed in the SFO following dehydration compared with control animals (22 upregulated and 24 downregulated), with the largest change being the greater than fivefold increase in brain-derived neurotrophic factor (BDNF) expression, while significant changes in the expression of the calcium-sensing (upregulated) and apelin (downregulated) receptors were also reported. In contrast, food deprivation caused greater than twofold changes in a total of 687 transcripts (222 upregulated and 465 downregulated), including significant reductions in vasopressin, oxytocin, promelanin concentrating hormone, cocaine amphetamine-related transcript (CART), and the endothelin type B receptor, as well as increases in the expression of the GABAB receptor. Of these regulated transcripts, we identified 37 that are commonly regulated by fasting and dehydration, nine that were uniquely regulated by dehydration, and 650 that are uniquely regulated by fasting. We also found five transcripts that were differentially regulated by fasting and dehydration including BDNF and CART. In these studies we have for the first time described the transcriptome of the rat SFO and have in addition identified genes, the expression of which is significantly modified by either water or food deprivation.

scholarly journals Investigation of the hepatoprotective properties of “Phytovenol” capsules on the model of medicamentous hepatitis in rats

2014 ◽  
Vol 27 (4) ◽  
pp. 240-242
Author(s):  
Oleg Gerush ◽  
Olena Lenytska ◽  
Larysa Yakovleva ◽  
Liudmyla Gladkova ◽  
Igor Gerush
Keyword(s):  
Pharmacological Activity ◽  
Medical Practice ◽  
Liver Diseases ◽  
Scientific Paper ◽  
Hepatoprotective Effect ◽  
Experimental Conditions ◽  
Medical Preparation ◽  
Quality Of Treatment ◽  
First Time

Abstract This scientific paper is an investigation of the pharmacological activity of the new medical preparation “Phytovenol” (capsules in the dose of 150 mg/kg) on the pattern of hepatitis in rats induced by paracetamol administration. The authors of the article, for the first time under experimental conditions, detected a hepatoprotective effect that was brought about by “Phytovenol” capsule administration. This is realized due to the antioxidant, antitoxic and anticytolytic activity of the examined medicine. The study found that its efficacy is not lower than the classical hepatoprotector - “Silibor” tablets. The results obtained suggest that it is possible to extend the range of available hepatoprotectors and improve the quality of treatment for liver diseases, by introducing “Phytovenol” capsules into medical practice.

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