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Glycerol To Glucose

Gluconeogenesis: Endogenous Glucose Synthesis

Gluconeogenesis: Endogenous Glucose Synthesis

Reactions of Gluconeogenesis: Gluconeogenesis from two moles of pyruvate to two moles of 1,3-bisphosphoglycerate consumes six moles of ATP. This makes the process of gluconeogenesis very costly from an energy standpoint considering that glucose oxidation to two moles of pyruvate yields two moles of ATP. The major hepatic substrates for gluconeogenesis (glycerol, lactate, alanine, and pyruvate) are enclosed in red boxes for highlighting. The reactions that take place in the mitochondria are pyruvate to OAA and OAA to malate. Pyruvate from the cytosol is transported across the inner mitochondrial membrane by the pyruvate transporter. Transport of pyruvate across the plasma membrane is catalyzed by the SLC16A1 protein (also called the monocarboxylic acid transporter 1, MCT1) and transport across the outer mitochondrial membrane involves a voltage-dependent porin transporter. Transport across the inner mitochondrial membrane requires a heterotetrameric transport complex (mitochondrial pyruvate carrier) consisting of the MPC1 gene and MPC2 gene encoded proteins. Following reduction of OAA to malate the malate is transported to the cytosol by the malate transporter (SLC25A11). In the cytosol the malate is oxidized to OAA and the OOA then feeds into the gluconeogenic pathway via conversion to PEP via PEPCK. The PEPCK reaction is another site for consumption of an ATP equivalent (GTP is utilized in the PEPCK reaction). The reversal of the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) reaction requires a supply of NADH. When lactate is the gluconeogenic substrate the NADH is supplied by the lactate dehydrogenase (LDH) reaction (indicated by the dashes lines), and it is supplied by the malate dehydrogenase reaction when pyruvate and alanine are the substrates. Secondly, one mo Continue reading >>

Assessment Of Bio-hydrogen Production From Glycerol And Glucose By Fermentative Bacteria | Dimanta | Energetika

Assessment Of Bio-hydrogen Production From Glycerol And Glucose By Fermentative Bacteria | Dimanta | Energetika

Assessment of bio-hydrogen production from glycerol and glucose by fermentative bacteria I. Dimanta, V. Nikolajeva, A. Gruduls, I. Muinieks, J. Kleperis Microorganisms are capable to produce hydrogen during fermentation of organic substrates and industrial waste products can be used as feedstock for hydrogen producing bacteria. One of the substrates that can be effectively used for microbial hydrogen production is glycerol, which is a by-product from the process of biodiesel production, but glucose is mainly used as a model substrate. Different bacterial isolates were tested for hydrogen gas production rates from glucose and glycerol with test-systems constructed in our laboratory. Test-systems were optimised to allow adequate substrate and bacterial strain hydrogen productivity estimation in the liquid and gaseous phases. It was concluded that several of the isolated bacterial strains are suitable for bio-hydrogen production using glycerol as a substrate. Assessment was developed to establish whether microbial conversion of glycerol is an economically and environmentally viable possibility for bio-hydrogen production. The raw material cost noticeably decreases because of large quantities of available crude glycerol after biodiesel production and the highly reduced nature of carbon in glycerol perse. Continue reading >>

Elucidation Of The Co-metabolism Of Glycerol And Glucose In Escherichia Coli By Genetic Engineering, Transcription Profiling, And 13c Metabolic Flux Analysis

Elucidation Of The Co-metabolism Of Glycerol And Glucose In Escherichia Coli By Genetic Engineering, Transcription Profiling, And 13c Metabolic Flux Analysis

Elucidation of the co-metabolism of glycerol and glucose in Escherichia coli by genetic engineering, transcription profiling, and 13C metabolic flux analysis Glycerol, a byproduct of biodiesel, has become a readily available and inexpensive carbon source for the production of high-value products. However, the main drawback of glycerol utilization is the low consumption rate and shortage of NADPH formation, which may limit the production of NADPH-requiring products. To overcome these problems, we constructed a carbon catabolite repression-negative ptsGglpK* mutant by both blocking a key glucose PTS transporter and enhancing the glycerol conversion. The mutant can recover normal growth by co-utilization of glycerol and glucose after loss of glucose PTS transporter. To reveal the metabolic potential of the ptsGglpK* mutant, this study examined the flux distributions and regulation of the co-metabolism of glycerol and glucose in the mutant. By labeling experiments using [1,3-13C]glycerol and [1-13C]glucose, 13C metabolic flux analysis was employed to decipher the metabolisms of both the wild-type strain and the ptsGglpK* mutant in chemostat cultures. When cells were maintained at a low dilution rate (0.1h1), the two strains showed similar fluxome profiles. When the dilution rate was increased, both strains upgraded their pentose phosphate pathway, glycolysis and anaplerotic reactions, while the ptsGglpK* mutant was able to catabolize much more glycerol than glucose (more than tenfold higher). Compared with the wild-type strain, the mutant repressed its flux through the TCA cycle, resulting in higher acetate overflow. The regulation of fluxomes was consistent with transcriptional profiling of several key genes relevant to the TCA cycle and transhydrogenase, namely gltA, icd Continue reading >>

Diabetes Enhances The Palatability Of Glycerol And Glucose

Diabetes Enhances The Palatability Of Glycerol And Glucose

Volume 29, Issue 3 , September 1982, Pages 561-566 Diabetes enhances the palatability of glycerol and glucose Author links open overlay panel Deborah J.Brief John D.Davis Get rights and content Male rats were provided with flavored solutions (0.3 M glucose, 0.3 M glycerol or 0.6 M glycerol) or water before and after the induction of diabetes by streptozotocin. Normal animals given 0.3 M glucose showed a significant increase in fluid intake but normal animals offered the glycerol solutions did not show an increase in intake compared to animals given water. After the onset of diabetes, exposure to the same flavored solutions resulted in significant increases in fluid intake by animals offered both the glycerol and glucose solutions. The animals offered glucose consumed significantly more than did the animals offered the glycerol solutions. The animals offered 0.6 M glycerol consumed significantly more than did the animals offered 0.3 M glycerol on 8 out of the 10 days of exposure. Therefore, while diabetes does not appear to modify the palatability of glucose it seems to produce an enhanced palatability for glycerol not seen in normal rats. Continue reading >>

Glycerol Production From Glucose And Fructose By 3t3-l1 Cells: A Mechanism Of Adipocyte Defense From Excess Substrate

Glycerol Production From Glucose And Fructose By 3t3-l1 Cells: A Mechanism Of Adipocyte Defense From Excess Substrate

Click through the PLOS taxonomy to find articles in your field. For more information about PLOS Subject Areas, click here . Glycerol Production from Glucose and Fructose by 3T3-L1 Cells: A Mechanism of Adipocyte Defense from Excess Substrate Affiliations Department of Nutrition and Food Science, Faculty of Biology, University of Barcelona, Av.Diagonal 643, 08028, Barcelona, Spain, Institute of Biomedicine, University of Barcelona, Barcelona, Spain, CIBER Obesity and Nutrition, Barcelona, Spain Affiliation Department of Nutrition and Food Science, Faculty of Biology, University of Barcelona, Av.Diagonal 643, 08028, Barcelona, Spain Affiliations Department of Nutrition and Food Science, Faculty of Biology, University of Barcelona, Av.Diagonal 643, 08028, Barcelona, Spain, Institute of Biomedicine, University of Barcelona, Barcelona, Spain, CIBER Obesity and Nutrition, Barcelona, Spain Affiliations Department of Nutrition and Food Science, Faculty of Biology, University of Barcelona, Av.Diagonal 643, 08028, Barcelona, Spain, Institute of Biomedicine, University of Barcelona, Barcelona, Spain, CIBER Obesity and Nutrition, Barcelona, Spain Continue reading >>

Fat To Glycerol To Glucose

Fat To Glycerol To Glucose

Fat to Glycerol to Glucose , 08-26-2009 11:18 PM ! ! ! I have been pursuing a low card woe for 8 months and have maintained the same weight basically since just after the first 2 weeks. Maintain carbs at 20 grams per day. Getting desperate. Got the book The metabolism Miracle by Diane Kress. She says basically that you body will use dietary fat for energy before it will use it's own fat stores. I'm confused. So I have done some reading online. Learning that dietary fat is turned into glycerol and then turned into glucose. So this tells me that dietary fat should be carefully controlled or at the very least you won't lose weight. I know there are some really smart people on this discussion board and I would really appreciate any information you can share. RE: Fat to Glycerol to Glucose , 08-27-2009 10:23 AM I'm confused. So I have done some reading online. Learning that dietary fat is turned into glycerol and then turned into glucose. So this tells me that dietary fat should be carefully controlled or at the very least you won't lose weight. I know there are some really smart people on this discussion board and I would really appreciate any information you can share. Your body's main energy "currency" is glucose. Even if you never ingested a carb, your body makes its own glucose, and if your BG gets much below 70 you'll feel the symptoms of low BG (shaky, weak, etc.) Fats (ingested and stored) are triglycerides. Glycerol is the small backbone connecting 3 fatty acids. Our bodies use the fatty acids for energy by oxidizing them (serially lopping off carbon fragments to form acyl CoA). For every gram of fat, the glycerol is a teeeeeeeeeny part -- kind of like the an artificial sweetener amount of grams if that makes any sense. I would not worry at all about regulating fat Continue reading >>

Gluconeogenesis

Gluconeogenesis

Not to be confused with Glycogenesis or Glyceroneogenesis. Simplified Gluconeogenesis Pathway Gluconeogenesis (GNG) is a metabolic pathway that results in the generation of glucose from certain non-carbohydrate carbon substrates. From breakdown of proteins, these substrates include glucogenic amino acids (although not ketogenic amino acids); from breakdown of lipids (such as triglycerides), they include glycerol (although not fatty acids); and from other steps in metabolism they include pyruvate and lactate. Gluconeogenesis is one of several main mechanisms used by humans and many other animals to maintain blood glucose levels, avoiding low levels (hypoglycemia). Other means include the degradation of glycogen (glycogenolysis)[1] and fatty acid catabolism. Gluconeogenesis is a ubiquitous process, present in plants, animals, fungi, bacteria, and other microorganisms.[2] In vertebrates, gluconeogenesis takes place mainly in the liver and, to a lesser extent, in the cortex of the kidneys. In ruminants, this tends to be a continuous process.[3] In many other animals, the process occurs during periods of fasting, starvation, low-carbohydrate diets, or intense exercise. The process is highly endergonic until it is coupled to the hydrolysis of ATP or GTP, effectively making the process exergonic. For example, the pathway leading from pyruvate to glucose-6-phosphate requires 4 molecules of ATP and 2 molecules of GTP to proceed spontaneously. Gluconeogenesis is often associated with ketosis. Gluconeogenesis is also a target of therapy for type 2 diabetes, such as the antidiabetic drug, metformin, which inhibits glucose formation and stimulates glucose uptake by cells.[4] In ruminants, because dietary carbohydrates tend to be metabolized by rumen organisms, gluconeogenesis occurs Continue reading >>

Glycerol-mediated Repression Of Glucose Metabolism And Glycerol Kinase As The Sole Route Of Glycerol Catabolism In The Haloarchaeon Haloferax Volcanii

Glycerol-mediated Repression Of Glucose Metabolism And Glycerol Kinase As The Sole Route Of Glycerol Catabolism In The Haloarchaeon Haloferax Volcanii

List of strains and plasmids used in this study For growth assays, cells were grown in yeast extract-peptone-Casamino Acids, Gly MM, Gly Glu MM, and Glu MM as indicated below. Cells from 80C glycerol stocks were freshly inoculated onto the appropriate agar-based media on plates. Cells were thrice subcultured and used as inocula for the final analyses of growth under various conditions as described below. Each subculture was inoculated to a final optical density at 600 nm (OD600) of 0.03 to 0.04. For the analyses of growth rates and cell yields, cells were grown in 20 ml of medium in 250-ml baffled Erlenmeyer flasks. For enzyme activity assays, cells were grown in 100 ml of Gly MM, Glu MM, or Gly Glu MM in 1,000-ml flasks. For RNA preparation, cells were grown in 3 ml of medium in 13- by 100-cm2 culture tubes. Cell growth was monitored by an increase in OD600 (where 1 OD600 unit equals approximately 109 CFUml1 for all strains used in this study). All experiments were performed at least in triplicate. DNA isolation and analysis.DNA was separated by electrophoresis using 0.8% (wt/vol) agarose gels in 1 TAE electrophoresis buffer (40 mM Tris acetate, 2 mM EDTA, pH 8.5). Plasmid DNA was isolated from E. coli strains by using the QIAprep spin miniprep kit (Qiagen, Valencia, CA). PCR products were purified by using the MinElute kit (Qiagen) prior to modification by a restriction enzyme (BamHI, HindIII, KpnI, XbaI, HpaI, or NdeI) or T4 DNA polynucleotide kinase. For rapid PCR screening, template DNA was extracted from H. volcanii mutant and parent strains and recombinant E. coli DH5 as described previously ( 28 ). For Southern blotting, H. volcanii genomic DNA was isolated from 5-ml cultures by DNA spooling ( 9 ). PCRs.High-fidelity double-stranded DNA used for the constructio Continue reading >>

Propionic Acid Fermentation Of Glycerol And Glucose By Propionibacterium Acidipropionici And Propionibacterium Freudenreichii Ssp.shermanii

Propionic Acid Fermentation Of Glycerol And Glucose By Propionibacterium Acidipropionici And Propionibacterium Freudenreichii Ssp.shermanii

A comparative study was carried out in anaerobic batch cultures on 20 g/l of either glycerol or glucose using two propionibacteria strains, Propionibacterium acidipropionici and Propionibacterium freudenreichii ssp. shermanii. In all cases, fermentation end-products were the same and consisted of propionic acid as the major product, acetic acid as the main by-product and two minor metabolites, n-propanol and succinic acid. Evidence was provided that greater production of propionic acid by propionibacteria was obtained with glycerol as carbon and energy sources. P. acidipropionici showed higher efficiency in glycerol conversion to propionic acid with a faster substrate consumption (0.64 g l1 h1) and a higher propionic acid production (0.42 g l1 h1 and 0.79 mol/mol). The almost exclusive production of propionic acid from glycerol by this bacterium suggested an homopropionic tendency of this fermentation. Acetic acid final concentration was two times lower on glycerol (2 g/l) than on glucose (4 g/l) for both micro-organisms. P. freudenreichii ssp. shermanii exhibited a glycerol fermentation pattern typical of non-associated glycerol-consumption-product formation. This could indicate a particular metabolism for P. freudenreichii ssp. shermanii oriented towards the production of other specific components. These results tend to show that glycerol could be an excellent alternative to conventional carbon sources such as carbohydrates for propionic acid production. FermentationPropionic AcidSuccinic AcidGlycerol ConversionExclusive Production These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves. Received: 21 May 1999 / Accepted: 1 November 1999 This is a preview of subscripti Continue reading >>

A Method For The Measurement Of Lactate, Glycerol And Fatty Acid Production From 14c-glucose In Primary Cultures Of Rat Epididymal Adipocytes

A Method For The Measurement Of Lactate, Glycerol And Fatty Acid Production From 14c-glucose In Primary Cultures Of Rat Epididymal Adipocytes

A method for the measurement of lactate, glycerol and fatty acid production from C-glucose in primary cultures of rat epididymal adipocytes A. C. Ho-Palma, F. Rotondo, M. D. M. Romero, S. Memmolo, X. Remesar, J. A. Fernndez-Lpez and M. Alemany, Anal. Methods, 2016,8, 7873 If you are not the author of this article and you wish to reproduce material from it in a third party non-RSC publication you must formally request permission using RightsLink. Go to our Instructions for using RightsLink page for details. Authors contributing to RSC publications (journal articles, books or book chapters) do not need to formally request permission to reproduce material contained in this article provided that the correct acknowledgement is given with the reproduced material. Reproduced material should be attributed as follows: Reproduced from Ref. XX with permission from the Centre National de la Recherche Scientifique (CNRS) and The Royal Society of Chemistry. Reproduced from Ref. XX with permission from the PCCP Owner Societies. Reproduced from Ref. XX with permission from the European Society for Photobiology, the European Photochemistry Association, and The Royal Society of Chemistry. For reproduction of material from all other RSC journals and books: Reproduced from Ref. XX with permission from The Royal Society of Chemistry. If the material has been adapted instead of reproduced from the original RSC publication "Reproduced from" can be substituted with "Adapted from". In all cases the Ref. XX is the XXth reference in the list of references. If you are the author of this article you do not need to formally request permission to reproduce figures, diagrams etc. contained in this article in third party publications or in a thesis or dissertation provided that the correct acknowledge Continue reading >>

Glucose Can Be Synthesized From Noncarbohydrate Precursors - Biochemistry - Ncbi Bookshelf

Glucose Can Be Synthesized From Noncarbohydrate Precursors - Biochemistry - Ncbi Bookshelf

Glucose is formed by hydrolysis of glucose 6-phosphate in a reaction catalyzed by glucose 6-phosphatase. We will examine each of these steps in turn. 16.3.2. The Conversion of Pyruvate into Phosphoenolpyruvate Begins with the Formation of Oxaloacetate The first step in gluconeogenesis is the carboxylation of pyruvate to form oxaloacetate at the expense of a molecule of ATP . Then, oxaloacetate is decarboxylated and phosphorylated to yield phosphoenolpyruvate, at the expense of the high phosphoryl-transfer potential of GTP . Both of these reactions take place inside the mitochondria. The first reaction is catalyzed by pyruvate carboxylase and the second by phosphoenolpyruvate carboxykinase. The sum of these reactions is: Pyruvate carboxylase is of special interest because of its structural, catalytic, and allosteric properties. The N-terminal 300 to 350 amino acids form an ATP -grasp domain ( Figure 16.25 ), which is a widely used ATP-activating domain to be discussed in more detail when we investigate nucleotide biosynthesis ( Section 25.1.1 ). The C -terminal 80 amino acids constitute a biotin-binding domain ( Figure 16.26 ) that we will see again in fatty acid synthesis ( Section 22.4.1 ). Biotin is a covalently attached prosthetic group, which serves as a carrier of activated CO2. The carboxylate group of biotin is linked to the -amino group of a specific lysine residue by an amide bond ( Figure 16.27 ). Note that biotin is attached to pyruvate carboxylase by a long, flexible chain. The carboxylation of pyruvate takes place in three stages: Recall that, in aqueous solutions, CO2 exists as HCO3- with the aid of carbonic anhydrase (Section 9.2). The HCO3- is activated to carboxyphosphate. This activated CO2 is subsequently bonded to the N-1 atom of the biotin ring to Continue reading >>

Comparison Of Glucose, Glycerol And Crude Glycerol Fermentation By Escherichia Coli K12

Comparison Of Glucose, Glycerol And Crude Glycerol Fermentation By Escherichia Coli K12

The ability of E. coli to transform crude glycerol, waste of biodiesel production, into ethanol will allow for a zero waste process stream, leading to an increase in the economic viability of biofuels industry. The main aspect of this investigation is to study and compare the use of glucose, glycerol and crude glycerol as a carbon source for anaerobic growth of E. coli in order to produce ethanol and H2. The comparison was carried out in two separate experiments. For glycerol and glucose, the effect of carbon source is investigated by a comparative growth analysis of E. coli in the two substrates under anaerobic conditions. For glycerol and crude glycerol, the effects of initial glycerol concentration, supplement concentration and agitation speed on final ethanol concentration and dry weight were tested. E. coli MG1655 (ATCC 700926) was obtained from Cedar Lane Labs. M9 minimal medium containing 990 ml distilled water, 2 ml of MgSO4, 10 ml of 20% glucose, 6.0 g Na2HPO4, 3.0 g KH2PO4, 0.5 g NaCl and 1.0 g NH4Cl was mixed; 3.6 g of agar was added to 240 ml of this medium, autoclaved and poured into petri dishes. 60 ml of the medium was used to rehydrate the bacteria pellet. The bacteria was then transferred to the prepared plates and grown overnight at 37C. Single colonies were then transplanted onto Luria Bertani agar plates and incubated overnight at 37C. Single colonies selected from these agar plates were used to generate 80% glycerol stock solutions which were then stored at 80C. The innoculum for experiments was prepared in hungate tubes (Bellco Glass, 2047-16125) filled with MOPS minimal media [ 9 ] supplemented with 1% 1.32 mMN2HPO4 and 0.1% 1 mol sodium selenite. The amount of 10% glycerol was added as carbon source and the pH adjusted to 6.3 with 1 M NaOH. Bact Continue reading >>

Glucose-to-glycerol Conversion In Long-lived Yeast Provides Anti-aging Effects

Glucose-to-glycerol Conversion In Long-lived Yeast Provides Anti-aging Effects

Cell biologists have found a more filling substitute for caloric restriction in extending the life span of simple organisms. Researchers show that yeast cells maintained on a glycerol diet live twice as long as normal -- as long as yeast cells on a severe caloric-restriction diet. They are also more resistant to cell damage. Cell biologists have found a more filling substitute for caloric restriction in extending the life span of simple organisms. In a study published May 8 in the open-access journal PLoS Genetics, researchers from the University of Southern California Andrus Gerontology Center show that yeast cells maintained on a glycerol diet live twice as long as normal -- as long as yeast cells on a severe caloric-restriction diet. They are also more resistant to cell damage. Many studies have shown that caloric restriction can extend the life span of a variety of laboratory animals. Caloric restriction is also known to cause major improvements in a number of markers for cardiovascular diseases in humans. This study is the first to propose that "dietary substitution" can replace "dietary restriction" in a living species. "If you add glycerol, or restrict caloric intake, you obtain the same effect," said senior author Valter Longo. "It's as good as calorie restriction, yet cells can take it up and utilize it to generate energy or for the synthesis of cellular components." Longo and colleagues Min Wei and Paola Fabrizio introduced a glycerol diet after discovering that genetically engineered long-lived yeast cells that survive up to 5-fold longer than normal have increased levels of the genes that produce glycerol. In fact, they convert virtually all the glucose and ethanol into glycerol. Notably, these cells have a reduced activity in the TOR1/SCH9 pathway, which i Continue reading >>

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An Error Occurred Setting Your User Cookie

An Error Occurred Setting Your User Cookie This site uses cookies to improve performance. If your browser does not accept cookies, you cannot view this site. There are many reasons why a cookie could not be set correctly. Below are the most common reasons: You have cookies disabled in your browser. You need to reset your browser to accept cookies or to ask you if you want to accept cookies. Your browser asks you whether you want to accept cookies and you declined. To accept cookies from this site, use the Back button and accept the cookie. Your browser does not support cookies. Try a different browser if you suspect this. The date on your computer is in the past. If your computer's clock shows a date before 1 Jan 1970, the browser will automatically forget the cookie. To fix this, set the correct time and date on your computer. You have installed an application that monitors or blocks cookies from being set. You must disable the application while logging in or check with your system administrator. This site uses cookies to improve performance by remembering that you are logged in when you go from page to page. To provide access without cookies would require the site to create a new session for every page you visit, which slows the system down to an unacceptable level. This site stores nothing other than an automatically generated session ID in the cookie; no other information is captured. In general, only the information that you provide, or the choices you make while visiting a web site, can be stored in a cookie. For example, the site cannot determine your email name unless you choose to type it. Allowing a website to create a cookie does not give that or any other site access to the rest of your computer, and only the site that created the cookie can read it. Continue reading >>

Glycerol Diffusion In Skin At Glucose Impact On Tissue

Glycerol Diffusion In Skin At Glucose Impact On Tissue

Glycerol diffusion in skin at glucose impact on tissue Abstract: In this paper we present results of experimental study of glucose impact on skin tissue by testing tissue structure alteration at glycerol diffusivity. The measurements have been performed using Ocean Optics spectrometer USB4000 in transmittance mode. In the in vitro experiments twenty samples of intact rat skin were used. Transmittance of ten samples was measured immediately after obtaining the samples concurrently with administration of 58% aqueous glycerol solution in the spectral range 400-1000 nm. The second group of the rat skin samples (ten samples) was incubated during 24 hours in 40%-glucose solution and during 24 hours in physiological solution. After that transmittance of the ten samples was measured concurrently with administration of the 58%- glycerol solution. Special computer program has been developed for processing of the experimental data and estimation of the glycerol diffusion rate. Degree of optical clearing of intact skin samples and skin samples previously immersed in glucose solution were estimated and compared. As a result we found that the optical clearing of intact skin increases about 3 times faster in comparison with skin immersed in the glucose solution. Continue reading >>

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