Reaction Process: PathBank:SMP0019095

De Novo Triacylglycerol Biosynthesis TG(20:0/18:1(9Z)/18:1(11Z)) related metabolites

find 12 related metabolites which is associated with chemical reaction(pathway) De Novo Triacylglycerol Biosynthesis TG(20:0/18:1(9Z)/18:1(11Z))

LPA(20:0/0:0) + Oleoyl-CoA ⟶ Coenzyme A + PA(20:0/18:1(9Z))

Coenzyme A

{[(2R,3S,4R,5R)-5-(6-amino-9H-purin-9-yl)-4-hydroxy-2-({[hydroxy({hydroxy[(3R)-3-hydroxy-2,2-dimethyl-3-({2-[(2-sulfanylethyl)carbamoyl]ethyl}carbamoyl)propoxy]phosphoryl}oxy)phosphoryl]oxy}methyl)oxolan-3-yl]oxy}phosphonic acid

C21H36N7O16P3S (767.1152)


Coenzyme A (CoA, CoASH, or HSCoA) is a coenzyme notable for its role in the synthesis and oxidization of fatty acids and the oxidation of pyruvate in the citric acid cycle. It is adapted from beta-mercaptoethylamine, panthothenate, and adenosine triphosphate. It is also a parent compound for other transformation products, including but not limited to, phenylglyoxylyl-CoA, tetracosanoyl-CoA, and 6-hydroxyhex-3-enoyl-CoA. Coenzyme A is synthesized in a five-step process from pantothenate and cysteine. In the first step pantothenate (vitamin B5) is phosphorylated to 4-phosphopantothenate by the enzyme pantothenate kinase (PanK, CoaA, CoaX). In the second step, a cysteine is added to 4-phosphopantothenate by the enzyme phosphopantothenoylcysteine synthetase (PPC-DC, CoaB) to form 4-phospho-N-pantothenoylcysteine (PPC). In the third step, PPC is decarboxylated to 4-phosphopantetheine by phosphopantothenoylcysteine decarboxylase (CoaC). In the fourth step, 4-phosphopantetheine is adenylylated to form dephospho-CoA by the enzyme phosphopantetheine adenylyl transferase (CoaD). Finally, dephospho-CoA is phosphorylated using ATP to coenzyme A by the enzyme dephosphocoenzyme A kinase (CoaE). Since coenzyme A is, in chemical terms, a thiol, it can react with carboxylic acids to form thioesters, thus functioning as an acyl group carrier. CoA assists in transferring fatty acids from the cytoplasm to the mitochondria. A molecule of coenzyme A carrying an acetyl group is also referred to as acetyl-CoA. When it is not attached to an acyl group, it is usually referred to as CoASH or HSCoA. Coenzyme A is also the source of the phosphopantetheine group that is added as a prosthetic group to proteins such as acyl carrier proteins and formyltetrahydrofolate dehydrogenase. Acetyl-CoA is an important molecule itself. It is the precursor to HMG CoA which is a vital component in cholesterol and ketone synthesis. Furthermore, it contributes an acetyl group to choline to produce acetylcholine in a reaction catalysed by choline acetyltransferase. Its main task is conveying the carbon atoms within the acetyl group to the citric acid cycle to be oxidized for energy production (Wikipedia). Coenzyme A (CoA, CoASH, or HSCoA) is a coenzyme, notable for its role in the synthesis and oxidization of fatty acids, and the oxidation of pyruvate in the citric acid cycle. It is adapted from beta-mercaptoethylamine, panthothenate and adenosine triphosphate. Acetyl-CoA is an important molecule itself. It is the precursor to HMG CoA, which is a vital component in cholesterol and ketone synthesis. Furthermore, it contributes an acetyl group to choline to produce acetylcholine, in a reaction catalysed by choline acetyltransferase. Its main task is conveying the carbon atoms within the acetyl group to the citric acid cycle to be oxidized for energy production. -- Wikipedia [HMDB]. Coenzyme A is found in many foods, some of which are grape, cowpea, pili nut, and summer savory. Coenzyme A (CoASH) is a ubiquitous and essential cofactor, which is an acyl group carrier and carbonyl-activating group for the citric acid cycle and fatty acid metabolism. Coenzyme A plays a central role in the oxidation of pyruvate in the citric acid cycle and the metabolism of carboxylic acids, including short- and long-chain fatty acids[1]. Coenzyme A (CoASH) is a ubiquitous and essential cofactor, which is an acyl group carrier and carbonyl-activating group for the citric acid cycle and fatty acid metabolism. Coenzyme A plays a central role in the oxidation of pyruvate in the citric acid cycle and the metabolism of carboxylic acids, including short- and long-chain fatty acids[1]. Coenzyme A, a ubiquitous essential cofactor, is an acyl group carrier and carbonyl-activating group for the citric acid cycle and fatty acid metabolism. Coenzyme A plays a central role in the metabolism of carboxylic acids, including short- and long-chain fatty acids. Coenzyme A. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=85-61-0 (retrieved 2024-10-17) (CAS RN: 85-61-0). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0).

   

Glycerol 3-phosphate

alpha-Glycerophosphoric acid, 1,2,3-propanetriol-1-(18)O,3-(dihydrogen phosphate)-labeled

C3H9O6P (172.0137)


Glycerol 3-phosphate, also known as glycerophosphoric acid or alpha-glycerophosphorate, is a member of the class of compounds known as glycerophosphates. Glycerophosphates are compounds containing a glycerol linked to a phosphate group. Glycerol 3-phosphate is soluble (in water) and a moderately acidic compound (based on its pKa). Glycerol 3-phosphate can be found in a number of food items such as sacred lotus, common oregano, mixed nuts, and yautia, which makes glycerol 3-phosphate a potential biomarker for the consumption of these food products. Glycerol 3-phosphate can be found primarily in blood, feces, saliva, and urine, as well as in human prostate tissue. Glycerol 3-phosphate exists in all living species, ranging from bacteria to humans. In humans, glycerol 3-phosphate is involved in several metabolic pathways, some of which include cardiolipin biosynthesis cl(i-12:0/i-21:0/a-21:0/i-21:0), cardiolipin biosynthesis cl(i-12:0/a-25:0/i-13:0/i-12:0), cardiolipin biosynthesis cl(i-13:0/i-21:0/i-21:0/a-25:0), and cardiolipin biosynthesis cl(i-13:0/a-25:0/i-18:0/a-13:0). Glycerol 3-phosphate is also involved in several metabolic disorders, some of which include de novo triacylglycerol biosynthesis tg(i-24:0/19:0/16:0), de novo triacylglycerol biosynthesis TG(16:0/22:4(7Z,10Z,13Z,16Z)/16:1(9Z)), de novo triacylglycerol biosynthesis TG(18:0/18:3(9Z,12Z,15Z)/14:1(9Z)), and de novo triacylglycerol biosynthesis TG(18:3(6Z,9Z,12Z)/22:5(4Z,7Z,10Z,13Z,16Z)/20:2(11Z,14Z)). Glycerol 3-phosphate is a chemical intermediate in the glycolysis metabolic pathway. It is commonly confused with the similarly named glycerate 3-phosphate or glyceraldehyde 3-phosphate. Glycerol 3-phosphate is produced from glycerol, the triose sugar backbone of triglycerides and glycerophospholipids, by the enzyme glycerol kinase. Glycerol 3-phospate may then be converted by dehydrogenation to dihydroxyacetone phosphate (DHAP) by the enzyme glycerol-3-phosphate dehydrogenase. DHAP can then be rearranged into glyceraldehyde 3-phosphate (GA3P) by triose phosphate isomerase (TIM), and feed into glycolysis. The glycerol 3-phosphate shuttle is used to rapidly regenerate NAD+ in the brain and skeletal muscle cells of mammals (wikipedia). Acquisition and generation of the data is financially supported in part by CREST/JST. KEIO_ID G072

   

Dihydroxyacetone phosphate

1,3-Dihydroxy-2-propanone monodihydrogen phosphoric acid

C3H7O6P (169.998)


An important intermediate in lipid biosynthesis and in glycolysis.; Dihydroxyacetone phosphate (DHAP) is a biochemical compound involved in many reactions, from the Calvin cycle in plants to the ether-lipid biosynthesis process in Leishmania mexicana. Its major biochemical role is in the glycolysis metabolic pathway. DHAP may be referred to as glycerone phosphate in older texts.; Dihydroxyacetone phosphate lies in the glycolysis metabolic pathway, and is one of the two products of breakdown of fructose 1,6-phosphate, along with glyceraldehyde 3-phosphate. It is rapidly and reversibly isomerised to glyceraldehyde 3-phosphate.; In the Calvin cycle, DHAP is one of the products of the sixfold reduction of 1,3-bisphosphoglycerate by NADPH. It is also used in the synthesis of sedoheptulose 1,7-bisphosphate and fructose 1,6-bisphosphate which are both used to reform ribulose 5-phosphate, the key carbohydrate of the Calvin cycle. Dihydroxyacetone phosphate is found in many foods, some of which are sesame, mexican groundcherry, parsley, and common wheat. [Spectral] Glycerone phosphate (exact mass = 169.99802) and beta-D-Fructose 1,6-bisphosphate (exact mass = 339.99605) and NADP+ (exact mass = 743.07545) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. Dihydroxyacetone phosphate is an important intermediate in lipid biosynthesis and in glycolysis. Dihydroxyacetone phosphate is found to be associated with transaldolase deficiency, which is an inborn error of metabolism. Dihydroxyacetone phosphate has been identified in the human placenta (PMID: 32033212). KEIO_ID D014

   

Nadide

beta-Nicotinamide adenine dinucleotide hydrate

[C21H28N7O14P2]+ (664.1169)


[Spectral] NAD+ (exact mass = 663.10912) and 3,4-Dihydroxy-L-phenylalanine (exact mass = 197.06881) and Cytidine (exact mass = 243.08552) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. [Spectral] NAD+ (exact mass = 663.10912) and NADP+ (exact mass = 743.07545) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. COVID info from COVID-19 Disease Map Corona-virus Coronavirus SARS-CoV-2 COVID-19 SARS-CoV COVID19 SARS2 SARS

   

1,4-Dihydronicotinamide adenine dinucleotide

Dihydronicotinamide-adenine dinucleotide

C21H29N7O14P2 (665.1248)


Nicotinamide adenine dinucleotide (NAD) is a coenzyme central to metabolism. Found in all living cells, NAD is called a dinucleotide because it consists of two nucleotides joined through their phosphate groups. One nucleotide contains an adenine nucleobase and the other nicotinamide. NAD exists in two forms: an oxidized and reduced form, abbreviated as NAD+ and NADH (H for hydrogen) respectively. NADH is the reduced form of NAD+, and NAD+ is the oxidized form of NADH. NAD (or nicotinamide adenine dinucleotide) is used extensively in glycolysis and the citric acid cycle of cellular respiration. The reducing potential stored in NADH can be either converted into ATP through the electron transport chain or used for anabolic metabolism. ATP "energy" is necessary for an organism to live. Green plants obtain ATP through photosynthesis, while other organisms obtain it via cellular respiration. NAD is a coenzyme composed of ribosylnicotinamide 5-diphosphate coupled to adenosine 5-phosphate by a pyrophosphate linkage. It is found widely in nature and is involved in numerous enzymatic reactions in which it serves as an electron carrier by being alternately oxidized (NAD+) and reduced (NADH). NADP is formed through the addition of a phosphate group to the 2 position of the adenosyl nucleotide through an ester linkage. NADH is the reduced form of NAD+, and NAD+ is the oxidized form of NADH, A coenzyme composed of ribosylnicotinamide 5-diphosphate coupled to adenosine 5-phosphate by pyrophosphate linkage. It is found widely in nature and is involved in numerous enzymatic reactions in which it serves as an electron carrier by being alternately oxidized (NAD+) and reduced (NADH). It forms NADP with the addition of a phosphate group to the 2 position of the adenosyl nucleotide through an ester linkage.(Dorland, 27th ed) [HMDB]. NADH is found in many foods, some of which are dill, ohelo berry, fox grape, and black-eyed pea. Acquisition and generation of the data is financially supported in part by CREST/JST. COVID info from COVID-19 Disease Map Corona-virus Coronavirus SARS-CoV-2 COVID-19 SARS-CoV COVID19 SARS2 SARS

   

Water

oxidane

H2O (18.0106)


Water is a chemical substance that is essential to all known forms of life. It appears colorless to the naked eye in small quantities, though it is actually slightly blue in color. It covers 71\\% of Earths surface. Current estimates suggest that there are 1.4 billion cubic kilometers (330 million m3) of it available on Earth, and it exists in many forms. It appears mostly in the oceans (saltwater) and polar ice caps, but it is also present as clouds, rain water, rivers, freshwater aquifers, lakes, and sea ice. Water in these bodies perpetually moves through a cycle of evaporation, precipitation, and runoff to the sea. Clean water is essential to human life. In many parts of the world, it is in short supply. From a biological standpoint, water has many distinct properties that are critical for the proliferation of life that set it apart from other substances. It carries out this role by allowing organic compounds to react in ways that ultimately allow replication. All known forms of life depend on water. Water is vital both as a solvent in which many of the bodys solutes dissolve and as an essential part of many metabolic processes within the body. Metabolism is the sum total of anabolism and catabolism. In anabolism, water is removed from molecules (through energy requiring enzymatic chemical reactions) in order to grow larger molecules (e.g. starches, triglycerides and proteins for storage of fuels and information). In catabolism, water is used to break bonds in order to generate smaller molecules (e.g. glucose, fatty acids and amino acids to be used for fuels for energy use or other purposes). Water is thus essential and central to these metabolic processes. Water is also central to photosynthesis and respiration. Photosynthetic cells use the suns energy to split off waters hydrogen from oxygen. Hydrogen is combined with CO2 (absorbed from air or water) to form glucose and release oxygen. All living cells use such fuels and oxidize the hydrogen and carbon to capture the suns energy and reform water and CO2 in the process (cellular respiration). Water is also central to acid-base neutrality and enzyme function. An acid, a hydrogen ion (H+, that is, a proton) donor, can be neutralized by a base, a proton acceptor such as hydroxide ion (OH-) to form water. Water is considered to be neutral, with a pH (the negative log of the hydrogen ion concentration) of 7. Acids have pH values less than 7 while bases have values greater than 7. Stomach acid (HCl) is useful to digestion. However, its corrosive effect on the esophagus during reflux can temporarily be neutralized by ingestion of a base such as aluminum hydroxide to produce the neutral molecules water and the salt aluminum chloride. Human biochemistry that involves enzymes usually performs optimally around a biologically neutral pH of 7.4. (Wikipedia). Water, also known as purified water or dihydrogen oxide, is a member of the class of compounds known as homogeneous other non-metal compounds. Homogeneous other non-metal compounds are inorganic non-metallic compounds in which the largest atom belongs to the class of other nonmetals. Water can be found in a number of food items such as caraway, oxheart cabbage, alaska wild rhubarb, and japanese walnut, which makes water a potential biomarker for the consumption of these food products. Water can be found primarily in most biofluids, including ascites Fluid, blood, cerebrospinal fluid (CSF), and lymph, as well as throughout all human tissues. Water exists in all living species, ranging from bacteria to humans. In humans, water is involved in several metabolic pathways, some of which include cardiolipin biosynthesis CL(20:4(5Z,8Z,11Z,14Z)/18:0/20:4(5Z,8Z,11Z,14Z)/18:2(9Z,12Z)), cardiolipin biosynthesis cl(i-13:0/i-15:0/i-20:0/i-24:0), cardiolipin biosynthesis CL(18:0/18:0/20:4(5Z,8Z,11Z,14Z)/22:5(7Z,10Z,13Z,16Z,19Z)), and cardiolipin biosynthesis cl(a-13:0/i-18:0/i-13:0/i-19:0). Water is also involved in several metabolic disorders, some of which include de novo triacylglycerol biosynthesis tg(i-21:0/i-13:0/21:0), de novo triacylglycerol biosynthesis tg(22:0/20:0/i-20:0), de novo triacylglycerol biosynthesis tg(a-21:0/i-20:0/i-14:0), and de novo triacylglycerol biosynthesis tg(i-21:0/a-17:0/i-12:0). Water is a drug which is used for diluting or dissolving drugs for intravenous, intramuscular or subcutaneous injection, according to instructions of the manufacturer of the drug to be administered [fda label]. Water plays an important role in the world economy. Approximately 70\\% of the freshwater used by humans goes to agriculture. Fishing in salt and fresh water bodies is a major source of food for many parts of the world. Much of long-distance trade of commodities (such as oil and natural gas) and manufactured products is transported by boats through seas, rivers, lakes, and canals. Large quantities of water, ice, and steam are used for cooling and heating, in industry and homes. Water is an excellent solvent for a wide variety of chemical substances; as such it is widely used in industrial processes, and in cooking and washing. Water is also central to many sports and other forms of entertainment, such as swimming, pleasure boating, boat racing, surfing, sport fishing, and diving .

   

cis-Vaccenoyl CoA

{[(2R,3R,5R)-5-(6-amino-9H-purin-9-yl)-4-hydroxy-2-({[hydroxy({hydroxy[(3R)-3-hydroxy-2,2-dimethyl-3-{[2-({2-[(11E)-octadec-11-enoylsulfanyl]ethyl}carbamoyl)ethyl]carbamoyl}propoxy]phosphoryl}oxy)phosphoryl]oxy}methyl)oxolan-3-yl]oxy}phosphonic acid

C39H68N7O17P3S (1031.3605)


Vaccenoyl CoA is a coenzyme A derivative of vaccenic acid. There are both cis (or R) and trans (or S) forms of Vaccenoyl CoA. Vaccenoyl CoA derivatives were found to be active substrates in vitro in the acylation of glycerol 3-phosphate. It is involved in the biosynthesis and oxidation of fatty acids as well as in ceramide formation. [HMDB] Vaccenoyl CoA is a coenzyme A derivative of vaccenic acid. There are both cis (or R) and trans (or S) forms of Vaccenoyl CoA. Vaccenoyl CoA derivatives were found to be active substrates in vitro in the acylation of glycerol 3-phosphate. It is involved in the biosynthesis and oxidation of fatty acids as well as in ceramide formation.

   

Hydrogen Ion

Hydrogen cation

H+ (1.0078)


Hydrogen ion, also known as proton or h+, is a member of the class of compounds known as other non-metal hydrides. Other non-metal hydrides are inorganic compounds in which the heaviest atom bonded to a hydrogen atom is belongs to the class of other non-metals. Hydrogen ion can be found in a number of food items such as lowbush blueberry, groundcherry, parsley, and tarragon, which makes hydrogen ion a potential biomarker for the consumption of these food products. Hydrogen ion exists in all living organisms, ranging from bacteria to humans. In humans, hydrogen ion is involved in several metabolic pathways, some of which include cardiolipin biosynthesis cl(i-13:0/a-25:0/a-21:0/i-15:0), cardiolipin biosynthesis cl(a-13:0/a-17:0/i-13:0/a-25:0), cardiolipin biosynthesis cl(i-12:0/i-13:0/a-17:0/a-15:0), and cardiolipin biosynthesis CL(16:1(9Z)/22:5(4Z,7Z,10Z,13Z,16Z)/18:1(11Z)/22:5(7Z,10Z,13Z,16Z,19Z)). Hydrogen ion is also involved in several metabolic disorders, some of which include de novo triacylglycerol biosynthesis TG(20:3(8Z,11Z,14Z)/22:6(4Z,7Z,10Z,13Z,16Z,19Z)/22:5(7Z,10Z,13Z,16Z,19Z)), de novo triacylglycerol biosynthesis TG(18:2(9Z,12Z)/20:0/20:4(5Z,8Z,11Z,14Z)), de novo triacylglycerol biosynthesis TG(18:4(6Z,9Z,12Z,15Z)/18:3(9Z,12Z,15Z)/18:4(6Z,9Z,12Z,15Z)), and de novo triacylglycerol biosynthesis TG(24:0/20:5(5Z,8Z,11Z,14Z,17Z)/24:0). A hydrogen ion is created when a hydrogen atom loses or gains an electron. A positively charged hydrogen ion (or proton) can readily combine with other particles and therefore is only seen isolated when it is in a gaseous state or a nearly particle-free space. Due to its extremely high charge density of approximately 2×1010 times that of a sodium ion, the bare hydrogen ion cannot exist freely in solution as it readily hydrates, i.e., bonds quickly. The hydrogen ion is recommended by IUPAC as a general term for all ions of hydrogen and its isotopes. Depending on the charge of the ion, two different classes can be distinguished: positively charged ions and negatively charged ions . Hydrogen ion is recommended by IUPAC as a general term for all ions of hydrogen and its isotopes. Depending on the charge of the ion, two different classes can be distinguished: positively charged ions and negatively charged ions. Under aqueous conditions found in biochemistry, hydrogen ions exist as the hydrated form hydronium, H3O+, but these are often still referred to as hydrogen ions or even protons by biochemists. [Wikipedia])

   

DG(20:0/18:1(9Z)/0:0)

(2S)-3-hydroxy-2-[(9Z)-octadec-9-enoyloxy]propyl icosanoate

C41H78O5 (650.5849)


DG(20:0/18:1(9Z)/0:0) is a diglyceride, or a diacylglycerol (DAG). It is a glyceride consisting of two fatty acid chains covalently bonded to a glycerol molecule through ester linkages. Diacylglycerols can have many different combinations of fatty acids attached at both the C-1 and C-2 positions. DG(20:0/18:1(9Z)/0:0), in particular, consists of one chain of arachidic acid at the C-1 position and one chain of oleic acid at the C-2 position. The arachidic acid moiety is derived from peanut oil, while the oleic acid moiety is derived from vegetable oils, especially olive and canola oil. Mono- and diacylglycerols are common food additives used to blend together certain ingredients, such as oil and water, which would not otherwise blend well. Dacylglycerols are often found in bakery products, beverages, ice cream, chewing gum, shortening, whipped toppings, margarine, and confections. Synthesis of diacylglycerol begins with glycerol-3-phosphate, which is derived primarily from dihydroxyacetone phosphate, a product of glycolysis (usually in the cytoplasm of liver or adipose tissue cells). Glycerol-3-phosphate is first acylated with acyl-coenzyme A (acyl-CoA) to form lysophosphatidic acid, which is then acylated with another molecule of acyl-CoA to yield phosphatidic acid. Phosphatidic acid is then de-phosphorylated to form diacylglycerol.Diacylglycerols are precursors to triacylglycerols (triglyceride), which are formed by the addition of a third fatty acid to the diacylglycerol under the catalysis of diglyceride acyltransferase. Since diacylglycerols are synthesized via phosphatidic acid, they will usually contain a saturated fatty acid at the C-1 position on the glycerol moiety and an unsaturated fatty acid at the C-2 position. DG(20:0/18:1(9Z)/0:0) belongs to the family of Diacylglycerols. These are glycerolipids lipids containing a common glycerol backbone to which at least one fatty acyl group is esterified. DG(20:0/18:1(9Z)/0:0) is also a substrate of diacylglycerol kinase. It is involved in the phospholipid metabolic pathway.

   

TG(20:0/18:1(9Z)/18:1(11Z))

(2S)-3-[(11Z)-octadec-11-enoyloxy]-2-[(9Z)-octadec-9-enoyloxy]propyl icosanoate

C59H110O6 (914.8302)


TG(20:0/18:1(9Z)/18:1(11Z)) is a monoarachidic acid triglyceride. Triglycerides (TGs or TAGs) are also known as triacylglycerols or triacylglycerides, meaning that they are glycerides in which the glycerol is esterified with three fatty acid groups (i.e. fatty acid trimesters of glycerol). TGs may be divided into three general types with respect to their acyl substituents. They are simple or monoacid if they contain only one type of fatty acid, diacid if they contain two types of fatty acids and triacid if three different acyl groups. Chain lengths of the fatty acids in naturally occurring triglycerides can be of varying lengths and saturations but 16, 18 and 20 carbons are the most common. TG(20:0/18:1(9Z)/18:1(11Z)), in particular, consists of one chain of arachidic acid at the C-1 position, one chain of oleic acid at the C-2 position and one chain of vaccenic acid at the C-3 position. TGs are the main constituent of vegetable oil and animal fats. TGs are major components of very low density lipoprotein (VLDL) and chylomicrons, play an important role in metabolism as energy sources and transporters of dietary fat. They contain more than twice the energy (9 kcal/g) of carbohydrates and proteins. In the intestine, triglycerides are split into glycerol and fatty acids (this process is called lipolysis) with the help of lipases and bile secretions, which can then move into blood vessels. The triglycerides are rebuilt in the blood from their fragments and become constituents of lipoproteins, which deliver the fatty acids to and from fat cells among other functions. Various tissues can release the free fatty acids and take them up as a source of energy. Fat cells can synthesize and store triglycerides. When the body requires fatty acids as an energy source, the hormone glucagon signals the breakdown of the triglycerides by hormone-sensitive lipase to release free fatty acids. As the brain cannot utilize fatty acids as an energy source, the glycerol component of triglycerides can be converted into glucose for brain fuel when it is broken down. (www.cyberlipid.org, www.wikipedia.org)
TAGs can serve as fatty acid stores in all cells, but primarily in adipocytes of adipose tissue. The major building block for the synthesis of triacylglycerides, in non-adipose tissue, is glycerol. Adipocytes lack glycerol kinase and so must use another route to TAG synthesis. Specifically, dihydroxyacetone phosphate (DHAP), which is produced during glycolysis, is the precursor for TAG synthesis in adipose tissue. DHAP can also serve as a TAG precursor in non-adipose tissues, but does so to a much lesser extent than glycerol. The use of DHAP for the TAG backbone depends on whether the synthesis of the TAGs occurs in the mitochondria and ER or the ER and the peroxisomes. The ER/mitochondria pathway requires the action of glycerol-3-phosphate dehydrogenase to convert DHAP to glycerol-3-phosphate. Glycerol-3-phosphate acyltransferase then esterifies a fatty acid to glycerol-3-phosphate thereby generating lysophosphatidic acid. The ER/peroxisome reaction pathway uses the peroxisomal enzyme DHAP acyltransferase to acylate DHAP to acyl-DHAP which is then reduced by acyl-DHAP reductase. The fatty acids that are incorporated into TAGs are activated to acyl-CoAs through the action of acyl-CoA synthetases. Two molecules of acyl-CoA are esterified to glycerol-3-phosphate to yield 1,2-diacylglycerol phosphate (also known as phosphatidic acid). The phosphate is then removed by phosphatidic acid phosphatase (PAP1), to generate 1,2-diacylglycerol. This diacylglycerol serves as the substrate for addition of the third fatty acid to make TAG. Intestinal monoacylglycerols, derived from dietary fats, can also serve as substrates for the synthesis of 1,2-diacylglycerols.

   

PA(20:0/18:1(9Z))

[(2R)-3-(icosanoyloxy)-2-[(9Z)-octadec-9-enoyloxy]propoxy]phosphonic acid

C41H79O8P (730.5512)


PA(20:0/18:1(9Z)) is a phosphatidic acid. It is a glycerophospholipid in which a phosphate moiety occupies a glycerol substitution site. As is the case with diacylglycerols, phosphatidic acids can have many different combinations of fatty acids of varying lengths and saturation attached at the C-1 and C-2 positions. Fatty acids containing 16, 18 and 20 carbons are the most common. PA(20:0/18:1(9Z)), in particular, consists of one chain of arachidic acid at the C-1 position and one chain of oleic acid at the C-2 position. Phosphatidic acids are quite rare but are extremely important as intermediates in the biosynthesis of triacylglycerols and phospholipids.

   

Phosphate Ion

Phosphate Ion

O4P-3 (94.9534)