Reaction Process: PathBank:SMP0002108
2-O-alpha-Mannosyl-D-glycerate Degradation related metabolites
find 8 related metabolites which is associated with chemical reaction(pathway) 2-O-alpha-Mannosyl-D-glycerate Degradation
Adenosine triphosphate + Glyceric acid ⟶ 2-Phospho-D-glyceric acid + Adenosine diphosphate + Hydrogen Ion
Adenosine triphosphate
Adenosine triphosphate, also known as atp or atriphos, is a member of the class of compounds known as purine ribonucleoside triphosphates. Purine ribonucleoside triphosphates are purine ribobucleotides with a triphosphate group linked to the ribose moiety. Adenosine triphosphate is slightly soluble (in water) and an extremely strong acidic compound (based on its pKa). Adenosine triphosphate can be found in a number of food items such as lichee, alpine sweetvetch, pecan nut, and black mulberry, which makes adenosine triphosphate a potential biomarker for the consumption of these food products. Adenosine triphosphate can be found primarily in blood, cellular cytoplasm, cerebrospinal fluid (CSF), and saliva, as well as throughout most human tissues. Adenosine triphosphate exists in all living species, ranging from bacteria to humans. In humans, adenosine triphosphate is involved in several metabolic pathways, some of which include phosphatidylethanolamine biosynthesis PE(16:0/18:4(6Z,9Z,12Z,15Z)), carteolol action pathway, phosphatidylethanolamine biosynthesis PE(20:3(5Z,8Z,11Z)/15:0), and carfentanil action pathway. Adenosine triphosphate is also involved in several metabolic disorders, some of which include lysosomal acid lipase deficiency (wolman disease), phosphoenolpyruvate carboxykinase deficiency 1 (PEPCK1), propionic acidemia, and the oncogenic action of d-2-hydroxyglutarate in hydroxygluaricaciduria. Moreover, adenosine triphosphate is found to be associated with rachialgia, neuroinfection, stroke, and subarachnoid hemorrhage. Adenosine triphosphate is a non-carcinogenic (not listed by IARC) potentially toxic compound. Adenosine triphosphate is a drug which is used for nutritional supplementation, also for treating dietary shortage or imbalanc. Adenosine triphosphate (ATP) is a complex organic chemical that participates in many processes. Found in all forms of life, ATP is often referred to as the "molecular unit of currency" of intracellular energy transfer. When consumed in metabolic processes, it converts to either the di- or monophosphates, respectively ADP and AMP. Other processes regenerate ATP such that the human body recycles its own body weight equivalent in ATP each day. It is also a precursor to DNA and RNA . ATP is able to store and transport chemical energy within cells. ATP also plays an important role in the synthesis of nucleic acids. ATP can be produced by various cellular processes, most typically in mitochondria by oxidative phosphorylation under the catalytic influence of ATP synthase. The total quantity of ATP in the human body is about 0.1 mole. The energy used by human cells requires the hydrolysis of 200 to 300 moles of ATP daily. This means that each ATP molecule is recycled 2000 to 3000 times during a single day. ATP cannot be stored, hence its consumption must closely follow its synthesis (DrugBank). Metabolism of organophosphates occurs principally by oxidation, by hydrolysis via esterases and by reaction with glutathione. Demethylation and glucuronidation may also occur. Oxidation of organophosphorus pesticides may result in moderately toxic products. In general, phosphorothioates are not directly toxic but require oxidative metabolism to the proximal toxin. The glutathione transferase reactions produce products that are, in most cases, of low toxicity. Paraoxonase (PON1) is a key enzyme in the metabolism of organophosphates. PON1 can inactivate some organophosphates through hydrolysis. PON1 hydrolyzes the active metabolites in several organophosphates insecticides as well as, nerve agents such as soman, sarin, and VX. The presence of PON1 polymorphisms causes there to be different enzyme levels and catalytic efficiency of this esterase, which in turn suggests that different individuals may be more susceptible to the toxic effect of organophosphate exposure (T3DB). ATP is an adenosine 5-phosphate in which the 5-phosphate is a triphosphate group. It is involved in the transportation of chemical energy during metabolic pathways. It has a role as a nutraceutical, a micronutrient, a fundamental metabolite and a cofactor. It is an adenosine 5-phosphate and a purine ribonucleoside 5-triphosphate. It is a conjugate acid of an ATP(3-). An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter. Adenosine triphosphate is a metabolite found in or produced by Escherichia coli (strain K12, MG1655). Adenosine-5-triphosphate is a natural product found in Chlamydomonas reinhardtii, Arabidopsis thaliana, and other organisms with data available. Adenosine Triphosphate is an adenine nucleotide comprised of three phosphate groups esterified to the sugar moiety, found in all living cells. Adenosine triphosphate is involved in energy production for metabolic processes and RNA synthesis. In addition, this substance acts as a neurotransmitter. In cancer studies, adenosine triphosphate is synthesized to examine its use to decrease weight loss and improve muscle strength. Adenosine triphosphate (ATP) is a nucleotide consisting of a purine base (adenine) attached to the first carbon atom of ribose (a pentose sugar). Three phosphate groups are esterified at the fifth carbon atom of the ribose. ATP is incorporated into nucleic acids by polymerases in the processes of DNA replication and transcription. ATP contributes to cellular energy charge and participates in overall energy balance, maintaining cellular homeostasis. ATP can act as an extracellular signaling molecule via interactions with specific purinergic receptors to mediate a wide variety of processes as diverse as neurotransmission, inflammation, apoptosis, and bone remodelling. Extracellular ATP and its metabolite adenosine have also been shown to exert a variety of effects on nearly every cell type in human skin, and ATP seems to play a direct role in triggering skin inflammatory, regenerative, and fibrotic responses to mechanical injury, an indirect role in melanocyte proliferation and apoptosis, and a complex role in Langerhans cell-directed adaptive immunity. During exercise, intracellular homeostasis depends on the matching of adenosine triphosphate (ATP) supply and ATP demand. Metabolites play a useful role in communicating the extent of ATP demand to the metabolic supply pathways. Effects as different as proliferation or differentiation, chemotaxis, release of cytokines or lysosomal constituents, and generation of reactive oxygen or nitrogen species are elicited upon stimulation of blood cells with extracellular ATP. The increased concentration of adenosine triphosphate (ATP) in erythrocytes from patients with chronic renal failure (CRF) has been observed in many studies but the mechanism leading to these abnormalities still is controversial. (A3367, A3368, A3369, A3370, A3371). Adenosine triphosphate is a metabolite found in or produced by Saccharomyces cerevisiae. An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter. Adenosine triphosphate (ATP) is a nucleotide consisting of a purine base (adenine) attached to the first carbon atom of ribose (a pentose sugar). Three phosphate groups are esterified at the fifth carbon atom of the ribose. ATP is incorporated into nucleic acids by polymerases in the processes of DNA replication and transcription. ATP contributes to cellular energy charge and participates in overall energy balance, maintaining cellular homeostasis. ATP can act as an extracellular signaling molecule via interactions with specific purinergic receptors to mediate a wide variety of processes as diverse as neurotransmission, inflammation, apoptosis, and bone remodelling. Extracellular ATP and its metabolite adenosine have also been shown to exert a variety of effects on nearly every cell type in human skin, and ATP seems to play a direct role in triggering skin inflammatory, regenerative, and fibrotic responses to mechanical injury, an indirect role in melanocyte proliferation and apoptosis, and a complex role in Langerhans cell-directed adaptive immunity. During exercise, intracellular homeostasis depends on the matching of adenosine triphosphate (ATP) supply and ATP demand. Metabolites play a useful role in communicating the extent of ATP demand to the metabolic supply pathways. Effects as different as proliferation or differentiation, chemotaxis, release of cytokines or lysosomal constituents, and generation of reactive oxygen or nitrogen species are elicited upon stimulation of blood cells with extracellular ATP. The increased concentration of adenosine triphosphate (ATP) in erythrocytes from patients with chronic renal failure (CRF) has been observed in many studies but the mechanism leading to these abnormalities still is controversial. (PMID: 15490415, 15129319, 14707763, 14696970, 11157473). 5′-ATP. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=56-65-5 (retrieved 2024-07-01) (CAS RN: 56-65-5). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0).
Adenosine diphosphate
Adenosine diphosphate (ADP), also known as adenosine pyrophosphate (APP), is an important organic compound in metabolism and is essential to the flow of energy in living cells. ADP consists of three important structural components: a sugar backbone attached to adenine and two phosphate groups bonded to the 5 carbon atom of ribose. The diphosphate group of ADP is attached to the 5’ carbon of the sugar backbone, while the adenine attaches to the 1’ carbon. ADP belongs to the class of organic compounds known as purine ribonucleoside diphosphates. These are purine ribobucleotides with diphosphate group linked to the ribose moiety. It is an ester of pyrophosphoric acid with the nucleotide adenine. Adenosine diphosphate is a nucleotide. ADP exists in all living species, ranging from bacteria to humans. In humans, ADP is involved in d4-gdi signaling pathway. ADP is the product of ATP dephosphorylation by ATPases. ADP is converted back to ATP by ATP synthases. ADP consists of the pyrophosphate group, the pentose sugar ribose, and the nucleobase adenine. Adenosine diphosphate, abbreviated ADP, is a nucleotide. It is an ester of pyrophosphoric acid with the nucleotide adenine. ADP consists of the pyrophosphate group, the pentose sugar ribose, and the nucleobase adenine. 5′-ADP. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=58-64-0 (retrieved 2024-07-01) (CAS RN: 58-64-0). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). Adenosine 5'-diphosphate (Adenosine diphosphate) is a nucleoside diphosphate. Adenosine 5'-diphosphate is the product of ATP dephosphorylation by ATPases. Adenosine 5'-diphosphate induces human platelet aggregation and inhibits stimulated adenylate cyclase by an action at P2T-purinoceptors. Adenosine 5'-diphosphate (Adenosine diphosphate) is a nucleoside diphosphate. Adenosine 5'-diphosphate is the product of ATP dephosphorylation by ATPases. Adenosine 5'-diphosphate induces human platelet aggregation and inhibits stimulated adenylate cyclase by an action at P2T-purinoceptors.
Glycerate
Glyceric acid is a colourless syrupy acid, obtained from oxidation of glycerol. It is a compound that is secreted excessively in the urine by patients suffering from D-glyceric aciduria, an inborn error of metabolism, and D-glycerate anemia. Deficiency of human glycerate kinase leads to D-glycerate acidemia/D-glyceric aciduria. Symptoms of the disease include progressive neurological impairment, hypotonia, seizures, failure to thrive, and metabolic acidosis. At sufficiently high levels, glyceric acid can act as an acidogen and a metabotoxin. An acidogen is an acidic compound that induces acidosis, which has multiple adverse effects on many organ systems. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Glyceric acid is an organic acid. Abnormally high levels of organic acids in the blood (organic acidemia), urine (organic aciduria), the brain, and other tissues lead to general metabolic acidosis. Acidosis typically occurs when arterial pH falls below 7.35. In infants with acidosis, the initial symptoms include poor feeding, vomiting, loss of appetite, weak muscle tone (hypotonia), and lack of energy (lethargy). These can progress to heart abnormalities, seizures, coma, and possibly death. These are also the characteristic symptoms of untreated glyceric aciduria. Many affected children with organic acidemias experience intellectual disability or delayed development. In adults, acidosis or acidemia is characterized by headaches, confusion, feeling tired, tremors, sleepiness, and seizures. Elevated values may also be due to microbial sources such as yeast (Aspergillus, Penicillium, probably Candida) or due to dietary sources containing glycerol (glycerine). Glyceric acid is isolated from various plants (e.g. brassicas, pulses, and Vicia faba). A colorless syrupy acid, obtained from oxidation of glycerol. It is a compound that is secreted excessively in the urine by patients suffering from D-glyceric aciduria and D-glycerate anemia. Deficiency of human glycerate kinase leads to D-glycerate acidemia/D-glyceric aciduria. Symptoms of the disease include progressive neurological impairment, hypotonia, seizures, failure to thrive and metabolic acidosis.; Glyceric acid is a natural three-carbon sugar acid. Salts and esters of glyceric acid are known as glycerates. Glyceric acid is found in many foods, some of which are peanut, common grape, garden tomato (variety), and french plantain. Glyceric acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=473-81-4 (retrieved 2024-06-29) (CAS RN: 473-81-4). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0).
2-Phospho-D-glyceric acid
2-Phosphoglyceric acid (2PG), or 2-phosphoglycerate, is a glyceric acid which serves as the substrate in the ninth step of glycolysis. It is catalyzed by enolase into phosphoenolpyruvate (PEP), the penultimate step in the conversion of glucose to pyruvate.; 2-Phosphoglyceric acid (2PGA) is a glyceric acid which serves as the substrate in the ninth step of glycolysis. It is catalyzed by enolase into phosphoenolpyruvate (PEP), the penultimate step in the conversion of glucose to pyruvate. Enolase catalyzes the beta-elimination reaction in a stepwise manner wherein OH- is eliminated from C3 of a discrete carbanion (enolate) intermediate. This intermediate is created by removal of the proton from C2 of 2PGA by a base in the active site. (PMID: 8994873, Wikipedia). 2-Phosphoglycerate is found in rice. 2-Phospho-D-glycerate or 2PG is an intermediate in gluconeogenesis. It is a glyceric acid which serves as the substrate in the ninth step of glycolysis. 2PG is converted by enolase into phosphoenolpyruvate (PEP), the penultimate step in the conversion of glucose to pyruvate. More specifically, 2PG can be generated from Glycerate-3-phosphate via phosphoglycerate mutase or from phosphoenolpyrvate via alpha enolase. KEIO_ID P029
Water
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 .
2-O-(6-Phospho-alpha-mannosyl)-D-glycerate
2-O-(6-Phospho-alpha-mannosyl)-D-glycerate is an alpha-D-mannosylglycerate (MG) that is an intermediate in 2-O-alpha-mannosyl-D-glycerate degradation. It can be generated from 2-O-alpha-mannosyl-D-glycerate via the enzyme 2-O-alpha-mannosyl-D-glycerate transporting phosphotransferase system (mngA). 2-O-Alpha-mannosyl-D-glycerate is a natural extremolyte identified in microorganisms growing under extremely high temperatures up to 100 oC, and had been shown to protect proteins against various stress conditions such as heat, freezing, thawing, and drying. MG that is naturally occurring hyperthermophilic osmolytes, could be potential drug candidates or lead compounds against alpha,beta aggregation associated with Alzheimers disease(PMID: 18304694). In most organisms MG is produced from guanosine pyrophosphate mannose (GDP-alpha-D-mannose) via mannosyl-3-phosphoglycerate in two steps, catalyzed by the enzymes mannosyl-3-phosphoglycerate synthase and mannosyl-3-phosphoglycerate phosphatase. [HMDB] 2-O-(6-Phospho-alpha-mannosyl)-D-glycerate is an alpha-D-mannosylglycerate (MG) that is an intermediate in 2-O-alpha-mannosyl-D-glycerate degradation. It can be generated from 2-O-alpha-mannosyl-D-glycerate via the enzyme 2-O-alpha-mannosyl-D-glycerate transporting phosphotransferase system (mngA). 2-O-Alpha-mannosyl-D-glycerate is a natural extremolyte identified in microorganisms growing under extremely high temperatures up to 100 oC, and had been shown to protect proteins against various stress conditions such as heat, freezing, thawing, and drying. MG that is naturally occurring hyperthermophilic osmolytes, could be potential drug candidates or lead compounds against alpha,beta aggregation associated with Alzheimers disease(PMID: 18304694). In most organisms MG is produced from guanosine pyrophosphate mannose (GDP-alpha-D-mannose) via mannosyl-3-phosphoglycerate in two steps, catalyzed by the enzymes mannosyl-3-phosphoglycerate synthase and mannosyl-3-phosphoglycerate phosphatase.
Mannose 6-phosphate
Mannose 6-phosphate, also known as alpha-D-mannose-6-p or man-6-p, belongs to the class of organic compounds known as hexose phosphates. These are carbohydrate derivatives containing a hexose substituted by one or more phosphate groups. Mannose 6-phosphate exists in all eukaryotes, ranging from yeast to humans. Within humans, mannose 6-phosphate participates in a number of enzymatic reactions. In particular, mannose 6-phosphate can be converted into fructose 6-phosphate through its interaction with the enzyme mannose-6-phosphate isomerase. In addition, mannose 6-phosphate can be biosynthesized from D-mannose through the action of the enzyme hexokinase-1. Mannose 6-phosphate is a potent competitive inhibitor of pinocytosis of human platelet beta-glucuronidase and it is a necessary component of the recognition marker on the enzyme for pinocytosis by human fibroblasts as well (PMID 908752). In humans, mannose 6-phosphate is involved in fructose intolerance, hereditary. Mannose-6-phosphate is a potent competitive inhibitor of pinocytosis of human platelet beta-glucuronidase and it is a necessary component of the recognition marker on the enzyme for pinocytosis by human fibroblasts as well (PMID 908752). [HMDB] Acquisition and generation of the data is financially supported in part by CREST/JST. KEIO_ID M008
Hydrogen Ion
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])