The Citric Acid Cycle
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WINE CHEM 101 Part B by Bob Peak
WINE CHEM 101 Part B By Bob Peak In last year’s catalog and newsletter, we began a discussion of the chemistry of wine and winemaking— Wine Chem 101, Part A—with details about conversion of sugars to alcohol. (That article is still available at thebeveragepeople. com). At the end of the article, I credited wine acids for the “zing” in wine flavor that lifts it above ordinary bever-ages. So, in this issue, I will tackle that part of Wine Chem: Acid. The two major organic acid components of grapes and grape juice are tartaric and malic acids, usually starting at about a 50-50 ratio. Together, they create the low pH conditions that help make wine a stable beverage and provide the pleasant tartness we all associate with it. The combined range of these acids in fresh grape juice will usually fall between 3 and 15 grams per liter (or 0.3 to 1.5%). Although this wide range of acid levels—measured as TA or Titratable Acidity—can be seen around the world, most North Coast grape juice comes in between 0.4 and 0.7% TA, with about 0.65% preferred. There is also a trace of citric acid in grapes, but it is not a significant contributor to TA. Together, these acids are the “fixed” acids of grape juice, joined in some wines by lactic acid from malolactic fermentation. The term “fixed” is used to distinguish from the spoilage acids of wine, the volatile acids. Those acids—mostly acetic acid—are the products of vinegar fermenta-tion and will introduce unpleasant aromas to wine at very low levels. -
Class 11 Biology Chapter- 13 Respiration in Plants
CLASS 11 BIOLOGY CHAPTER- 13 RESPIRATION IN PLANTS CELLULAR RESPIRATION: The process of conversion of the chemical energy of organic substances into a metabolically usable energy within living cells is called cellular respiration. TYPES OF CELLULAR RESPIRATION: (i) Aerobic respiration: The process of respiration which requires molecular oxygen. (ii) Anaerobic respiration: The process of respiration which does not require molecular oxygen and occurs in the cytoplasm. MECHANISM OF RESPIRATION: Following are the steps- 1. GLYCOLYSIS / EMP Pathway: It involves a series of closely integrated reactions in which hexose sugars(usually glucose) are converted into pyruvic acid. It is common in both aerobic and anaerobic reactions. It occurs in the cytoplasm. It does not require oxygen. Gollowing are the steps of GLYCLOLYSIS: (i) Conversion of glucose to Fructose-1,6-diphosphate: First phosphorylation: Glucose is converted to Glucose -6-phosphate in the presence of enzyme hexokinase and Mg++ ions and energy in the form of ATP. Isomerization: Glucose-6-phosphate is converted to Fructose-6-phosphate in the presence of phosphohexoisomerase. Second phosphorylation: Fructose-6-phosphate is converted to Fructose-1,6- diphosphate by the use of energy in the form of ATP. (ii) Formation of pyruvic acid from fructose -1,6-diphosphate: Cleavage: Fructose-1,6-diphosphate splits into 3-phosphoglyceraldehyde and Dihydroxyacetone phosphate in the presence of enzyme aldolase. Phosphorylation and oxidative dehydrogenase: 3-phosphoglyceraldehyde is converted to 1,3-biphosphoglyceric acid. ATP generation(first): 1,3-biphosphoglyceric acid is converted to 3-phosphoglyceric acid in the presence of Mg++ and phosphoglycerokinase . Isomerization: 3-phosphoglyceric acid is converted to 2-phosphoglyceric acid in the presence of Mg++. -
Detection and Formation Scenario of Citric Acid, Pyruvic Acid, and Other Possible Metabolism Precursors in Carbonaceous Meteorites
Detection and formation scenario of citric acid, pyruvic acid, and other possible metabolism precursors in carbonaceous meteorites George Coopera,1, Chris Reeda, Dang Nguyena, Malika Cartera, and Yi Wangb aExobiology Branch, Space Science Division, National Aeronautics and Space Administration-Ames Research Center, Moffett Field, CA 94035; and bDevelopment, Planning, Research, and Analysis/ZymaX Forensics Isotope, 600 South Andreasen Drive, Suite B, Escondido, CA 92029 Edited by David Deamer, University of California, Santa Cruz, CA, and accepted by the Editorial Board July 1, 2011 (received for review April 12, 2011) Carbonaceous meteorites deliver a variety of organic compounds chained three-carbon (3C) pyruvic acid through the eight-carbon to Earth that may have played a role in the origin and/or evolution (8C) 7-oxooctanoic acid and the branched 6C acid, 3-methyl- of biochemical pathways. Some apparently ancient and critical 4-oxopentanoic acid (β-methyl levulinic acid), Fig. 1, Table S1. metabolic processes require several compounds, some of which 2-methyl-4-oxopenanoic acid (α-methyl levulinic acid) is tenta- are relatively labile such as keto acids. Therefore, a prebiotic setting tively identified (i.e., identified by mass spectral interpretation for any such individual process would have required either a only). As a group, these keto acids are relatively unusual in that continuous distant source for the entire suite of intact precursor the ketone carbon is located in a terminal-acetyl group rather molecules and/or an energetic and compact local synthesis, parti- than at the second carbon as in most of the more biologically cularly of the more fragile members. -
The Clinical Significance of the Organic Acids Test
The Clinical Significance of the Organic Acids Test The Organic Acids Test (OAT) provides an accurate metabolic snapshot of what is going on in the body. Besides offering the most complete and accurate evaluation of intestinal yeast and bacteria, it also provides information on important neurotransmitters, nutritional markers, glutathione status, oxalate metabolism, and much more. The test includes 76 urinary metabolite markers that can be very useful for discovering underlying causes of chronic illness. Patients and physicians report that treating yeast and bacterial abnormalities reduces fatigue, increases alertness and energy, improves sleep, normalizes bowel function, and reduces hyperactivity and abdominal pain. The OAT Assists in Evaluating: ■ Krebs Cycle Abnormalities ■ Neurotransmitter Levels ■ Nutritional Deficiencies ■ Antioxidant Deficiencies ■ Yeast and Clostridia Overgrowth ■ Fatty Acid Metabolism ■ Oxalate Levels ■ And More! The OAT Pairs Well with the Following Tests: ■ GPL-TOX: Toxic Non-Metal Chemical Profile ■ IgG Food Allergy + Candida ■ MycoTOX Profile ■ Phospholipase A2 Activity Test Learn how to better integrate the OAT into your practice, along with our other top tests by attending one of our GPL Academy Practitioner Workshops! Visit www.GPLWorkshops.com for workshop dates and locations. The following pages list the 76 metabolite markers of the Organic Acids Test. Included is the name of the metabolic marker, its clinical significance, and usual initial treatment. INTESTINAL MICROBIAL OVERGROWTH Yeast and Fungal Markers Elevated citramalic acid is produced mainly by Saccharomyces species or Propionibacteria Citramalic Acid overgrowth. High-potency, multi-strain probiotics may help rebalance GI flora. A metabolite produced by Aspergillus and possibly other fungal species in the GI tract. 5-Hydroxy-methyl- Prescription or natural antifungals, along with high-potency, multi-strain probiotics, furoic Acid may reduce overgrowth levels. -
Chapter 7. "Coenzymes and Vitamins" Reading Assignment
Chapter 7. "Coenzymes and Vitamins" Reading Assignment: pp. 192-202, 207-208, 212-214 Problem Assignment: 3, 4, & 7 I. Introduction Many complex metabolic reactions cannot be carried out using only the chemical mechanisms available to the side-chains of the 20 standard amino acids. To perform these reactions, enzymes must rely on other chemical species known broadly as cofactors that bind to the active site and assist in the reaction mechanism. An enzyme lacking its cofactor is referred to as an apoenzyme whereas the enzyme with its cofactor is referred to as a holoenzyme. Cofactors are subdivided into essential ions and organic molecules known as coenzymes (Fig. 7.1). Essential ions, commonly metal ions, may participate in substrate binding or directly in the catalytic mechanism. Coenzymes typically act as group transfer agents, carrying electrons and chemical groups such as acyl groups, methyl groups, etc., depending on the coenzyme. Many of the coenzymes are derived from vitamins which are essential for metabolism, growth, and development. We will use this chapter to introduce all of the vitamins and coenzymes. In a few cases--NAD+, FAD, coenzyme A--the mechanisms of action will be covered. For the remainder of the water-soluble vitamins, discussion of function will be delayed until we encounter them in metabolism. We also will discuss the biochemistry of the fat-soluble vitamins here. II. Inorganic cation cofactors Many enzymes require metal cations for activity. Metal-activated enzymes require or are stimulated by cations such as K+, Ca2+, or Mg2+. Often the metal ion is not tightly bound and may even be carried into the active site attached to a substrate, as occurs in the case of kinases whose actual substrate is a magnesium-ATP complex. -
Tricarboxylic Acid (TCA) Cycle Intermediates: Regulators of Immune Responses
life Review Tricarboxylic Acid (TCA) Cycle Intermediates: Regulators of Immune Responses Inseok Choi , Hyewon Son and Jea-Hyun Baek * School of Life Science, Handong Global University, Pohang, Gyeongbuk 37554, Korea; [email protected] (I.C.); [email protected] (H.S.) * Correspondence: [email protected]; Tel.: +82-54-260-1347 Abstract: The tricarboxylic acid cycle (TCA) is a series of chemical reactions used in aerobic organisms to generate energy via the oxidation of acetylcoenzyme A (CoA) derived from carbohydrates, fatty acids and proteins. In the eukaryotic system, the TCA cycle occurs completely in mitochondria, while the intermediates of the TCA cycle are retained inside mitochondria due to their polarity and hydrophilicity. Under cell stress conditions, mitochondria can become disrupted and release their contents, which act as danger signals in the cytosol. Of note, the TCA cycle intermediates may also leak from dysfunctioning mitochondria and regulate cellular processes. Increasing evidence shows that the metabolites of the TCA cycle are substantially involved in the regulation of immune responses. In this review, we aimed to provide a comprehensive systematic overview of the molecular mechanisms of each TCA cycle intermediate that may play key roles in regulating cellular immunity in cell stress and discuss its implication for immune activation and suppression. Keywords: Krebs cycle; tricarboxylic acid cycle; cellular immunity; immunometabolism 1. Introduction The tricarboxylic acid cycle (TCA, also known as the Krebs cycle or the citric acid Citation: Choi, I.; Son, H.; Baek, J.-H. Tricarboxylic Acid (TCA) Cycle cycle) is a series of chemical reactions used in aerobic organisms (pro- and eukaryotes) to Intermediates: Regulators of Immune generate energy via the oxidation of acetyl-coenzyme A (CoA) derived from carbohydrates, Responses. -
Acetyl Coenzyme a (Sodium Salt) 08/19
FOR RESEARCH ONLY! Acetyl Coenzyme A (sodium salt) 08/19 ALTERNATE NAMES: S-[2-[3-[[4-[[[5-(6-aminopurin-9-yl)-4-hydroxy-3-phosphonooxyoxolan-2-yl]methoxy- hydroxyphosphoryl]oxy-hydroxyphosphoryl]oxy-2-hydroxy-3,3- dimethylbutanoyl]amino]propanoylamino]ethyl] ethanethioate, sodium; S-acetate coenzyme A, trisodium salt; Acetyl CoA, trisodium salt; Acetyl-S- CoA, trisodium salt CATALOG #: B2844-1 1 mg B2844-5 5 mg STRUCTURE: MOLECULAR FORMULA: C₂₃H₃₈N₇O₁₇P₃S•3Na MOLECULAR WEIGHT: 878.5 CAS NUMBER: 102029-73-2 APPEARANCE: A crystalline solid PURITY: ≥90% ~10 mg/ml in PBS, pH 7.2 SOLUBILITY: DESCRIPTION: Acetyl-CoA is an essential cofactor and carrier of acyl groups in enzymatic reactions. It is formed either by the oxidative decarboxylation of pyruvate, β-oxidation of fatty acids or oxidative degradation of certain amino acids. It is an intermediate in fatty acid and amino acid metabolism. It is the starting compound for the citric acid cycle. It is a precursor for the neurotransmitter acetylcholine. It is required for acetyltransferases and acyltransferases in the post-translational modification of proteins. STORAGE TEMPERATURE: -20ºC HANDLING: Do not take internally. Wear gloves and mask when handling the product! Avoid contact by all modes of exposure. REFERENCES: 1. Palsson-McDermott, E.M., and O'Neill, L.A. The Warburg effect then and now: From cancer to inflammatory diseases. BioEssays 35(11), 965-973 (2013). 2. Akram, M. Citric acid cycle and role of its intermediates in metabolism. Cell Biochemistry and Biophysics 68(3), 475-478 (2014). 3. Miura, Y. The biological significance of ω-oxidation of fatty acids. -
Acetaldehyde Stimulation of Net Gluconeogenic Carbon Movement from Applied Malic Acid in Tomato Fruit Pericarp Tissue'12
Plant Physiol. (1991) 95, 954-960 Received for publication July 18, 1990 0032-0889/91 /95/0954/07/$01 .00/0 Accepted November 16, 1990 Acetaldehyde Stimulation of Net Gluconeogenic Carbon Movement from Applied Malic Acid in Tomato Fruit Pericarp Tissue'12 Anna Halinska3 and Chaim Frenkel* Department of Horticulture, Rutgers-The State University, New Brunswick, New Jersey 08903 ABSTRACT appears to stimulate a respiratory upsurge in climacteric and Applied acetaldehyde is known to lead to sugar accumulation nonclimacteric fruit including blueberry and strawberry (13) in fruit including tomatoes (Lycopersicon esculentum) (O Paz, HW as well as in potato tubers (24) and an enhanced metabolite Janes, BA Prevost, C Frenkel [1982] J Food Sci 47: 270-274) turnover in ripening fig (9). The action of AA may be inde- presumably due to stimulation of gluconeogenesis. This conjec- pendent of ethylene, because AA was shown on one hand to ture was examined using tomato fruit pencarp discs as a test inhibit ethylene biosynthesis (E Pesis, personal communica- system and applied -[U-14C]malic acid as the source for gluco- tion) and on the other to promote softening and degreening neogenic carbon mobilization. The label from malate was re- in pear even when ethylene biosynthesis and action were covered in respiratory C02, in other organic acids, in ethanol arrested ( 14). insoluble material, and an appreciable amount in the ethanol The finding that AA application is accompanied by an soluble sugar fraction. In Rutgers tomatoes, the label recovery in increase in the total sugars content in tomato (19, 21) raises the sugar fraction and an attendant label reduction in the organic acids fraction intensified with fruit ripening. -
Seeding the Pregenetic Earth: Meteoritic Abundances Of
Accepted for publication in ApJ A Preprint typeset using LTEX style emulateapj v. 5/2/11 SEEDING THE PREGENETIC EARTH: METEORITIC ABUNDANCES OF NUCLEOBASES AND POTENTIAL REACTION PATHWAYS Ben K. D. Pearce1,4 and Ralph E. Pudritz2,3,5 Accepted for publication in ApJ ABSTRACT Carbonaceous chondrites are a class of meteorite known for having a high content of water and organics. In this study, abundances of the nucleobases, i.e., the building blocks of RNA and DNA, found in carbonaceous chondrites are collated from a variety of published data and compared across various meteorite classes. An extensive review of abiotic chemical reactions producing nucleobases is then performed. These reactions are then reduced to a list of 15 individual reaction pathways that could potentially occur within meteorite parent bodies. The nucleobases guanine, adenine and uracil are found in carbonaceous chondrites in the amounts of 1–500 ppb. It is currently unknown which reaction is responsible for their synthesis within the meteorite parent bodies. One class of carbonaceous meteorites dominate the abundances of both amino acids and nucleobases—the so-called CM2 (e.g. Murchison meteorite). CR2 meteorites (e.g. Graves Nunataks) also dominate the abundances of amino acids, but are the least abundant in nucleobases. The abundances of total nucleobases in these two classes are 330 ± 250 ppb and 16 ± 13 ppb respectively. Guanine most often has the greatest abundances in carbonaceous chondrites with respect to the other nucleobases, but is 1–2 orders of magnitude less abundant in CM2 meteorites than glycine (the most abundant amino acid). Our survey of the reaction mechanisms for nucleobase formation suggests that Fischer-Tropsch synthesis (i.e. -
Production of Succinic Acid by E.Coli from Mixtures of Glucose
2005:230 CIV MASTER’S THESIS Production of Succinic Acid by E. coli from Mixtures of Glucose and Fructose ANDREAS LENNARTSSON MASTER OF SCIENCE PROGRAMME Chemical Engineering Luleå University of Technology Department of Chemical Engineering and Geosciences Division of Biochemical and Chemical Engineering 2005:230 CIV • ISSN: 1402 - 1617 • ISRN: LTU - EX - - 05/230 - - SE Abstract Succinic acid, derived from fermentation of renewable feedstocks, has the possibility of replacing petrochemicals as a building block chemical. Another interesting advantage with biobased succinic acid is that the production does not contribute to the accumulation of CO2 to the environment. The produced succinic acid can therefore be considered as a “green” chemical. The bacterium used in this project is a strain of Escherichia coli called AFP184 that has been metabolically engineered to produce succinic acid in large quantities from glucose during anaerobic conditions. The objective with this thesis work was to evaluate whether AFP184 can utilise fructose, both alone and in mixtures with glucose, as a carbon source for the production of succinic acid. Hydrolysis of sucrose yields a mixture of fructose and glucose in equal ratio. Sucrose is a common sugar and the hydrolysate is therefore an interesting feedstock for the production of succinic acid. Fermentations with an initial sugar concentration of 100 g/L were conducted. The sugar ratios used were 100 % fructose, 100 % glucose and a mixture with 50 % fructose and glucose, respectively. The fermentation media used was a lean, low- cost media based on corn steep liquor and a minimal addition of inorganic salts. Fermentations were performed with a 12 L bioreactor and the acid and sugar concentrations were analysed with an HPLC system. -
Oxaloacetate As the Hill Oxidant in Mesophyll Cells of Plants Possessing
Proc. Nat. Acad. Sci. USA Vol. 70, No. 12, Part II, pp. 3730-3734, December 1973 Oxaloacetate as the Hill Oxidant in Mesophyll Cells of Plants Possessing the C4-Dicarboxylic Acid Cycle of Leaf Photosynthesis (CO2 fixation/uncoupler/photochemical reactions/electron transport/02 evolution) MARVIN L. SALIN, WILBUR H. CAMPBELL, AND CLANTON C. BLACK, JR. Department of Biochemistry, University of Georgia, Athens, Ga. 30602 Communicated by Harland G. Wood, August 16, 1973 ABSTRACT Isolated mesophyll cells from leaves of NADP+-dependent malic dehydrogenase (10) is in the meso- plants that use the C4 dicarboxylic acid pathway of CO2 fixation have been used to demonstrate that oxaloacetic phyll cells (9, 11). Therefore, one could reason that in meso- acid reduction to malic acid is coupled to the photo- phyll cells the carboxylation of PEP should be coupled to the chemical evolution of oxygen through the presumed pro- reduction of OAA and the required reduced pyridine nucleo- duction ofNADPH. The major acid-stable product oflight- tide should be produced photosynthetically as follows: dependent CO2 fixation is shown to be malic acid. In the presence of phosphoenolpyruvate and bicarbonate the PEP stoichiometry of CO2 fixation into acid-stable products to HC03- + PEP OAA + Pi [1] 02 evolution is shown to be near 1.0. Thus oxaloacetic acid carboxylase acts directly as the Hill oxidant in mesophyll cell chloro- light plasts. The experiments are taken as a firm demonstration that the dicarboxylic acid cycle of photosynthesis is the NADP++H20 NADPH+ 1/202+H+ [2] C4 mesophyll cell major pathway for the fixation of CO2 in mesophyll cells chloroplasts of plants having this pathway. -
Antibiotics As a Feed Additive Promote Growth of Chickens by Modulating the Gut Microbiome
Antibiotics as a Feed Additive Promote Growth of Chickens by Modulating the Gut Microbiome Xiangkai Li ( [email protected] ) Lanzhou University https://orcid.org/0000-0002-5704-9791 Ying Wu Lanzhou University Liang Peng Lanzhou University Rong Han Lanzhou University pengya Feng Lanzhou University Aman Khan Lanzhou University Pu Liu Lanzhou University Research Keywords: Antibiotic, Gut microbiota, Metabonomic, Lipid and amid acid metabolism, Immune response Posted Date: June 7th, 2021 DOI: https://doi.org/10.21203/rs.3.rs-571302/v1 License: This work is licensed under a Creative Commons Attribution 4.0 International License. Read Full License Page 1/31 Abstract Background: Antibiotics widely used as growth promoters in the agricultural industry, but their mechanisms have not been fully explored. Antibiotics has a connection effect on the gut microbiome which plays a vital role in host metabolism and immune response. Here, we investigated the association of antibiotic and gut microbiome in broiler chicken. Methods: Polymyxin (PMX) and amoxicillin (AMX) were selected as feed additives in broiler chicken, and gut bacterial composition assessed by quantitative real-time PCR and high-throughput sequencing of bacterial 16S rRNA. Metabolome and lipidomic of feces and serum samples were analyzed using liquid chromatograpy-tandem mass spectrometry (LC-MS). We further assessed changes in the microbiota and metabolism which underwent antibiotics treatment. Results: The administration of antibiotic increasing, the average weight of chickens by up to 4.9% and altered number and structure of the intestinal microora compared to the un-treated group. The bacterial component of gut microbiota in antibiotic groups was showed a lower prevalence of Firmicutes and Bacteroidetes phyla and higher prevalence of a high diversity (Proteobacteria).