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NAD biosynthesis I from aspartate related metabolites
find 6 related metabolites which is associated with chemical reaction(pathway) NAD biosynthesis I from aspartate
L-Aspartic acid ⟶ Iminoaspartic acid
L-Aspartic acid
Aspartic acid (Asp), also known as L-aspartic acid or as aspartate, the name of its anion, is an alpha-amino acid. These are amino acids in which the amino group is attached to the carbon atom immediately adjacent to the carboxylate group (alpha carbon). Amino acids are organic compounds that contain amino (–NH2) and carboxyl (–COOH) functional groups, along with a side chain (R group) specific to each amino acid. L-aspartic acid is one of 20 proteinogenic amino acids, i.e., the amino acids used in the biosynthesis of proteins. Aspartic acid is found in all organisms ranging from bacteria to plants to animals. It is classified as an acidic, charged (at physiological pH), aliphatic amino acid. In humans, aspartic acid is a nonessential amino acid derived from glutamic acid by enzymes using vitamin B6. However, in the human body, aspartate is most frequently synthesized through the transamination of oxaloacetate. A non-essential amino acid is an amino acid that can be synthesized from central metabolic pathway intermediates in humans and is not required in the diet. As its name indicates, aspartic acid is the carboxylic acid analog of asparagine. The D-isomer of aspartic acid (D-aspartic acid) is one of two D-amino acids commonly found in mammals. Aspartic acid was first discovered in 1827 by Auguste-Arthur Plisson and Étienne Ossian Henry by hydrolysis of asparagine, which had been isolated from asparagus juice in 1806. Aspartate has many biochemical roles. It is a neurotransmitter, a metabolite in the urea cycle and it participates in gluconeogenesis. It carries reducing equivalents in the malate-aspartate shuttle, which utilizes the ready interconversion of aspartate and oxaloacetate, which is the oxidized (dehydrogenated) derivative of malic acid. Aspartate donates one nitrogen atom in the biosynthesis of inosine, the precursor to the purine bases which are key to DNA biosynthesis. In addition, aspartic acid acts as a hydrogen acceptor in a chain of ATP synthase. Aspartic acid is a major excitatory neurotransmitter, which is sometimes found to be increased in epileptic and stroke patients. It is decreased in depressed patients and in patients with brain atrophy. As a neurotransmitter, aspartic acid may provide resistance to fatigue and thus lead to endurance, although the evidence to support this idea is not strong (Wikipedia). Aspartic acid supplements are being evaluated. Five grams can raise blood levels. Magnesium and zinc may be natural inhibitors of some of the actions of aspartic acid. Aspartic acid, when chemically coupled with the amino acid D-phenylalanine, is a part of a natural sweetener, aspartame. This sweetener is an advance in artificial sweeteners, and is probably safe in normal doses to all except phenylketonurics. Aspartic acid may be a significant immunostimulant of the thymus and can protect against some of the damaging effects of radiation. Aspartic acid is found in higher abundance in: oysters, luncheon meats, sausage meat, wild game, sprouting seeds, oat flakes, avocado, asparagus, young sugarcane, and molasses from sugar beets. [Spectral] L-Aspartate (exact mass = 133.03751) and Taurine (exact mass = 125.01466) and L-Asparagine (exact mass = 132.05349) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. [Spectral] L-Aspartate (exact mass = 133.03751) and L-Threonine (exact mass = 119.05824) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. L-Aspartic acid is is an amino acid, shown to be a suitable proagent for colon-specific agent deliverly. L-Aspartic acid is is an amino acid, shown to be a suitable proagent for colon-specific agent deliverly.
Quinolinic acid
Quinolinic acid, also known as quinolinate, belongs to the class of organic compounds known as pyridinecarboxylic acids. Pyridinecarboxylic acids are compounds containing a pyridine ring bearing a carboxylic acid group. It is also classified as a pyridine-2,3-dicarboxylic acid, which is a dicarboxylic acid with a pyridine backbone. Quinolinic acid is a colorless solid. In plants, it is the biosynthetic precursor to nicotine. Quinolinic acid is found in all organisms, from microbes to plants to animals. Quinolinic acid can be biosynthesized via aspartic acid in plants. Oxidation of aspartate by the enzyme aspartate oxidase gives iminosuccinate, containing the two carboxylic acid groups that are found in quinolinic acid. Condensation of iminosuccinate with glyceraldehyde-3-phosphate, mediated by quinolinate synthase, affords quinolinic acid Quinolinic acid is also a downstream product of the kynurenine pathway, which metabolizes the amino acid tryptophan ((PMID: 22678511). The kynurenine/tryptophan degradation pathway is important for its production of the coenzyme nicotinamide adenine dinucleotide (NAD+) and produces several neuroactive intermediates including quinolinic acid, kynurenine (KYN), kynurenic acid (KYNA), 3-hydroxykynurenine (3-HK), and 3-hydroxyanthranilic acid (3-HANA). In animals quinolinic acid acts as an NMDA receptor agonist and has a possible role in neurodegenerative disorders (PMID: 22678511). It also acts as a neurotoxin, gliotoxin, proinflammatory mediator, and pro-oxidant molecule (PMID: 22248144). Quinolinic acid can act as an endogenous brain excitotoxin when released by activated macrophages (PMID: 15013955). Within the brain, quinolinic acid is only produced by activated microglia and macrophages. Quinolinic acid is unable to pass through the blood-brain barrier (BBB) and must be produced within the brain by microglial cells or macrophages that have passed the BBB (PMID: 22248144). While quinolinic acid cannot pass through the BBB, kynurenic acid, tryptophan and 3-hydroxykynurenine can and can subsequently act as precursors to the production of quinolinic acid in the brain (PMID: 22248144). Quinolinic acid has potent neurotoxic effects. Studies have demonstrated that quinolinic acid may be involved in many psychiatric disorders and neurodegenerative diseases in the brain including ALS, Alzheimer’s disease, brain ischemia, Parkinson’s disease, Huntington’s disease and AIDS-dementia. Elevated CSF levels of quinolinic acid are correlated with the severity of neuropsychological deficits in patients who have AIDS. Indeed, levels of quinolinic acid in the CSF of AIDS patients suffering from AIDS-dementia can be up to twenty times higher than normal (PMID: 10936623). Quinolinic acid levels are increased in the brains of children infected with a range of bacterial infections of the central nervous system (CNS), of poliovirus patients, and of Lyme disease with CNS involvement patients. In addition, raised quinolinic acid levels have been found in traumatic CNS injury patients, patients suffering from cognitive decline with ageing, hyperammonaemia patients, hypoglycaemia patients, and systemic lupus erythematosus patients. Quinolinic acid has also been detected, but not quantified in, several different foods, such as Ceylon cinnamons, pitanga, Oregon yampahs, red bell peppers, and durians. This could make quinolinic acid a potential biomarker for the consumption of these foods. Quinolinic acid, also known as pyridine-2,3-dicarboxylate or 2,3-pyridinedicarboxylic acid, is a member of the class of compounds known as pyridinecarboxylic acids. Pyridinecarboxylic acids are compounds containing a pyridine ring bearing a carboxylic acid group. Quinolinic acid is slightly soluble (in water) and an extremely strong acidic compound (based on its pKa). Quinolinic acid can be found in a number of food items such as coconut, pistachio, chinese chives, and common bean, which makes quinolinic acid a potential biomarker for the consumption of these food products. Quinolinic acid can be found primarily in blood, cerebrospinal fluid (CSF), and urine, as well as throughout most human tissues. Quinolinic acid exists in all living species, ranging from bacteria to humans. In humans, quinolinic acid is involved in a couple of metabolic pathways, which include nicotinate and nicotinamide metabolism and tryptophan metabolism. Moreover, quinolinic acid is found to be associated with malaria, anemia, cNS tumors, and aIDS. Quinolinic acid has a potent neurotoxic effect. Studies have demonstrated that quinolinic acid may be involved in many psychiatric disorders, neurodegenerative processes in the brain, as well as other disorders. Within the brain, quinolinic acid is only produced by activated microglia and macrophages . Quinolinic acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=89-00-9 (retrieved 2024-07-09) (CAS RN: 89-00-9). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). Quinolinic acid is an endogenous N-methyl-D-aspartate (NMDA) receptor agonist synthesized from L-tryptophan via the kynurenine pathway and thereby has the potential of mediating N-methyl-D-aspartate neuronal damage and dysfunction[1][2]. Quinolinic acid is an endogenous N-methyl-D-aspartate (NMDA) receptor agonist synthesized from L-tryptophan via the kynurenine pathway and thereby has the potential of mediating N-methyl-D-aspartate neuronal damage and dysfunction[1][2].
Nicotinic acid mononucleotide
Nicotinic acid mononucleotide, also known as nicotinate ribonucleotide, belongs to the class of organic compounds known as nicotinic acid nucleotides. These are pyridine nucleotides in which the pyridine base is nicotinic acid or a derivative thereof. Nicotinic acid mononucleotide is an extremely weak basic (essentially neutral) compound (based on its pKa). Nicotinic acid mononucleotide an intermediate in the cofactor biosynthesis and the nicotinate and nicotinamide metabolism pathways. It is a substrate for nicotinamide riboside kinase, ectonucleotide pyrophosphatase/phosphodiesterase, nicotinamide mononucleotide adenylyltransferase, 5-nucleotidase, nicotinate-nucleotide pyrophosphorylase, and 5(3)-deoxyribonucleotidase. Nicotinic acid mononucleotide is an intermediate in the metabolism of Nicotinate and nicotinamide. It is a substrate for Ectonucleotide pyrophosphatase/phosphodiesterase 2, Ectonucleotide pyrophosphatase/phosphodiesterase 1, Nicotinamide mononucleotide adenylyltransferase 3, Cytosolic 5-nucleotidase IA, Cytosolic 5-nucleotidase IB, Nicotinate-nucleotide pyrophosphorylase, 5(3)-deoxyribonucleotidase (cytosolic type), Cytosolic purine 5-nucleotidase, Nicotinamide mononucleotide adenylyltransferase 2, Ectonucleotide pyrophosphatase/phosphodiesterase 3, 5-nucleotidase, 5(3)-deoxyribonucleotidase (mitochondrial) and Nicotinamide mononucleotide adenylyltransferase 1. [HMDB] NaMN is the most common mononucleotide intermediate (a hub) in NAD biogenesis. For example, in E. coli all three pyridine precursors are converted into NaMN (Table 1 and Figure 3(a)). Qa produced by the de novo Asp–DHAP pathway (genes nadB and nadA) is converted into NaMN by QAPRT (gene nadC). Salvage of both forms of niacin proceeds via NAPRT (gene pncB) either directly upon or after deamidation by NMDSE (gene pncA). Overall, more than 90\% of approximately 680 analyzed bacterial genomes contain at least one of the pathways leading to the formation of NaMN. Most of them (∼480 genomes) have the entire set of nadBAC genes for NaMN de novo synthesis from Asp that are often clustered on the chromosome and/or are co-regulated by the same transcription factors (see Section 7.08.3.1.2). Among the examples provided in Table 1, F. tularensis (Figure 4(c)) has all three genes of this de novo pathway forming a single operon-like cluster and supporting the growth of this organism in the absence of any pyridine precursors in the medium. More than half the genomes with the Asp–DHAP pathway also contain a deamidating niacin salvage pathway (genes pncAB) as do many representatives of the α-, β-, and γ-Proteobacteria, Actinobacteria, and Bacillus/Clostridium group. As already emphasized, the genomic reconstruction approach provides an assessment of the metabolic potential of an organism, which may or may not be realized under given conditions. For example, E. coli and B. subtilis can utilize both de novo and PncAB Nm salvage pathways under the same growth conditions, whereas in M. tuberculosis (having the same gene pattern) the latter pathway was considered nonfunctional, so that the entire NAD pool is generated by the de novo NadABC route. However, a recent study demonstrated the functional activity of the Nm salvage pathway in vivo, under hypoxic conditions in infected macrophages.221 This study also implicated the two downstream enzymes of NAD synthesis (NAMNAT and NADSYN) as attractive chemotherapeutic targets to treat acute and latent forms of tuberculosis. In approximately 100 species, including many Cyanobacteria (e.g., Synechococcus spp.), Bacteroidetes (e.g., Chlorobium spp.) and Proteobacteria (e.g., Caulobacter crescentus, Zymomonas mobilis, Desulfovibrio spp., and Shewanella spp. representing α-, β-, δ-, and γ-groups, respectively) the Asp–DHAP pathway is the only route to NAD biogenesis. Among them, nearly all Helicobacter spp. (except H. hepaticus), contain only the two genes nadA and nadC but lack the first gene of the pathway (nadB), which is a likely subject of nonorthologous gene replacement. One case of NadB (ASPOX) replacement by the ASPDH enzyme in T. maritima (and methanogenic archaea) was discussed in Section 7.08.2.1. However, no orthologues of the established ASPDH could be identified in Helicobacter spp. as well as in approximately 15 other diverse bacterial species that have the nadAC but lack the nadB gene (e.g., all analyzed Corynebacterium spp. except for C. diphtheriae). Therefore, the identity of the ASPOX or ASPDH enzyme in these species is still unknown, representing one of the few remaining cases of ‘locally missing genes’220 in the NAD subsystem. All other bacterial species contain either both the nadA and nadB genes (plus nadC) or none. In a limited number of bacteria (∼20 species), mostly in the two distant groups of Xanthomonadales (within γ-Proteobacteria) and Flavobacteriales (within Bacteroidetes), the Asp–DHAP pathway of Qa synthesis is replaced by the Kyn pathway. As described in Section 7.08.2.1.2, four out of five enzymes (TRDOX, KYNOX, KYNSE, and HADOX) in the bacterial version of this pathway are close homologues of the respective eukaryotic enzymes, whereas the KYNFA gene is a subject of multiple nonorthologous replacements. Although the identity of one alternative form of KYNFA (gene kynB) was established in a group of bacteria that have a partial Kyn pathway for Trp degradation to anthranilate (e.g., in P. aeruginosa or B. cereus57), none of the known KYNFA homologues are present in Xanthomonadales or Flavobacteriales. In a few species (e.g., Salinispora spp.) a complete gene set of the Kyn pathway genes co-occurs with a complete Asp–DHAP pathway. Further experiments would be required to establish to what extent and under what conditions these two pathways contribute to Qa formation. As discussed, the QAPRT enzyme is shared by both de novo pathways, and a respective gene, nadC is always found in the genomes containing one or the other pathway. Similarly, gene nadC always co-occurs with Qa de novo biosynthetic genes with one notable exception of two groups of Streptococci, S. pneumonaie and S. pyogenes. Although all other members of the Lactobacillales group also lack the Qa de novo biosynthetic machinery and rely entirely on niacin salvage, only these two human pathogens contain a nadC gene. The functional significance of this ‘out of context’ gene is unknown, but it is tempting to speculate that it may be involved in a yet-unknown pathway of Qa salvage from the human host. Among approximately 150 bacterial species that lack de novo biosynthesis genes and rely on deamidating salvage of niacin (via NAPRT), the majority (∼100) are from the group of Firmicutes. Such a functional variant (illustrated for Staphylococcus aureus in Figure 4(b)) is characteristic of many bacterial pathogens, both Gram-positive and Gram-negative (e.g., Brucella, Bordetella, and Campylobacter spp. from α-, β-, and δ-Proteobacteria, Borrelia, and Treponema spp. from Spirochaetes). Most of the genomes in this group contain both pncA and pncB genes that are often clustered on the chromosome and/or are co-regulated (see Section 7.08.3.1.2). In some cases (e.g., within Mollicutes and Spirochaetales), only the pncB, but not the pncA gene, can be reliably identified, suggesting that either of these species can utilize only the deamidated form of niacin (Na) or that some of them contain an alternative (yet-unknown) NMASE. Although the nondeamidating conversion of Nm into NMN (via NMPRT) appears to be present in approximately 50 bacterial species (mostly in β- and γ-Proteobacteria), it is hardly ever the only route of NAD biogenesis in these organisms. The only possible exception is observed in Mycoplasma genitalium and M. pneumoniae that contain the nadV gene as the only component of pyridine mononucleotide biosynthetic machinery. In some species (e.g., in Synechocystes spp.), the NMPRT–NMNAT route is committed primarily to the recycling of endogenous Nm. On the other hand, in F. tularensis (Figure 4(c)), NMPRT (gene nadV) together with NMNAT (of the nadM family) constitute the functional nondeamidating Nm salvage pathway as it supports the growth of the nadE′-mutant on Nm but not on Na (L. Sorci et al., unpublished). A similar nondeamidating Nm salvage pathway implemented by NMPRT and NMNAT (of the nadR family) is present in some (but not all) species of Pasteurellaceae in addition to (but never instead of) the RNm salvage pathway (see below), as initially demonstrated for H. ducreyi.128 A two-step conversion of NaMN into NAD via a NaAD intermediate (Route I in Figure 2) is present in the overwhelming majority of bacteria. The signature enzyme of Route I, NAMNAT of the NadD family is present in nearly all approximately 650 bacterial species that are expected to generate NaMN via de novo or salvage pathways (as illustrated by Figures 3(a) and 3(b)). All these species, without a single exception, also contain NADSYN (encoded by either a short or a long form of the nadE gene), which is required for this route. The species that lack the NadD/NadE signature represent several relatively rare functional variants, including: 1. Route I of NAD synthesis (NaMN → NaAD → NAD) variant via a bifunctional NAMNAT/NMNAT enzyme of the NadM family is common for archaea (see Section 7.08.3.2), but it appears to be present in only a handful of bacteria, such as Acinetobacter, Deinococcus, and Thermus groups. Another unusual feature of the latter two groups is the absence of the classical NADKIN, a likely subject of a nonorthologous replacement that remains to be elucidated. 2. Route II of NAD synthesis (NaMN → NMN → NAD). This route is implemented by a combination of the NMNAT of either the NadM family (as in F. tularensis) or the NadR family (as in M. succinoproducens and A. succinogenes) with NMNSYN of the NadE′ family. The case of F. tularensis described in Section 7.08.2.4 is illustrated in Figure 3(b). The rest of the NAD biosynthetic machinery in both species from the Pasteurellaceae group, beyond the shared Route II, is remarkably different from that in F. tularensis. Instead of de novo biosynthesis, they harbor a Na salvage pathway via NAPRT encoded by a pncB gene that is present in a chromosomal cluster with nadE′. Neither of these two genes are present in other Pasteurellaceae that lack the pyridine carboxylate amidation machinery (see below). 3. Salvage of RNm (RNm → NMN → NAD). A genomic signature of this pathway, a combination of the PnuC-like transporter and a bifunctional NMNAT/RNMKIN of the NadR family, is present in many Enterobacteriaceae and in several other diverse species (e.g., in M. tuberculosis). However, in H. influenzae (Figure 3(d)) and related members of Pasteurellaceae, it is the only route of NAD biogenesis. As shown in Table 1, H. influenzae as well as many other members of this group have lost nearly all components of the rich NAD biosynthetic machinery that are present in their close phylogenetic neighbors (such as E. coli and many other Enterobacteriaceae). This pathway is an ultimate route for utilization of the so called V-factors (NADP, NAD, NMN, or RNm) that are required to support growth of H. influenzae. It was established that all other V-factors are degraded to RNm by a combination of periplasmic- and membrane-associated hydrolytic enzymes.222 Although PnuC was initially considered an NMN transporter,223 its recent detailed analysis in both H. influenzae and Salmonella confirmed that its actual physiological function is in the uptake of RNm coupled with the phosphorylation of RNM to NMN by RNMKIN.17,148,224 As already mentioned, H. ducreyi and several other V-factor-independent members of the Pasteurellaceae group (H. somnus, Actinobacillus pleuropneumoniae, and Actinomycetemcomitans) harbor the NMNAT enzyme (NadV) that allows them to grow in the presence of Nm (but not Na) in the medium (Section 7.08.2.2). 4. Uptake of the intact NAD. Several groups of phylogenetically distant intracellular endosymbionts with extremely truncated genomes contain only a single enzyme, NADKIN, from the entire subsystem. Among them are all analyzed species of the Wolbachia, Rickettsia, and Blochmannia groups. These species are expected to uptake and utilize the intact NAD from their host while retaining the ability to convert it into NADP. Among all analyzed bacteria, only the group of Chlamydia does not have NADKIN and depends on the salvage of both NAD and NADP via a unique uptake system.157 A comprehensive genomic reconstruction of the metabolic potential (gene annotations and asserted pathways) across approximately 680 diverse bacterial genomes sets the stage for the accurate cross-genome projection and prediction of regulatory mechanisms that control the realization of this potential in a variety of species and growth conditions. In the next section, we summarize the recent accomplishments in the genomic reconstruction of NAD-related regulons in bacteria. Nicotinic acid mononucleotide. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=321-02-8 (retrieved 2024-06-29) (CAS RN: 321-02-8). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0).
Nicotinic acid adenine dinucleotide
Nicotinic acid adenine dinucleotide, also known as deamido-NAD or NAAD, belongs to the class of organic compounds known as (5->5)-dinucleotides. These are dinucleotides where the two bases are connected via a (5->5)-phosphodiester linkage. NAAD is possibly soluble (in water) and a strong basic compound (based on its pKa). NAAD exists in all living species, ranging from bacteria to humans. L-Glutamine and NAAD can be converted into L-glutamic acid and NAD; which is catalyzed by the enzyme glutamine-dependent nad(+) synthetase. In humans, NAAD is involved in the nicotinate and nicotinamide metabolism pathway. NAAD is also involved in the metabolic disorder called succinic semialdehyde dehydrogenase deficiency. Outside of the human body, NAAD has been detected, but not quantified in, several different foods, such as japanese walnuts, cauliflowers, sparkleberries, komatsuna, and macadamia nut (m. tetraphylla). This could make NAAD a potential biomarker for the consumption of these foods. NAAD is the product of the degradation of Nicotinic acid adenine dinucleotide phosphate (NAADP) by a Ca2+-sensitive phosphatase. NAADP is a Ca2+-mobilizing second messenger which is synthesized, in response to extracellular stimuli, via the base-exchange reaction by an ADP-ribosyl cyclase (ARC) family members (such as CD38). NAADP binds to and opens Ca2+ channels on intracellular organelles, thereby increasing the intracellular Ca2+ concentration which, in turn, modulates a variety of cellular processes. Structurally, NAADP it is a dinucleotide that only differs from the house-keeping enzyme cofactor, NADP, by a hydroxyl group (replacing the nicotinamide amino group) and yet this minor modification converts it into the most potent Ca2+-mobilizing second messenger yet described. NAADP may also be broken down to 2-phosphoadenosine diphosphoribose (ADPRP) by CD38 or reduced to NAADPH. Deamido-nad(+), also known as deamidonicotinamide adenine dinucleoetide, is a member of the class of compounds known as (5->5)-dinucleotides (5->5)-dinucleotides are dinucleotides where the two bases are connected via a (5->5)-phosphodiester linkage. Deamido-nad(+) is slightly soluble (in water) and a moderately acidic compound (based on its pKa). Deamido-nad(+) can be found in a number of food items such as garden tomato, sea-buckthornberry, pitanga, and japanese walnut, which makes deamido-nad(+) a potential biomarker for the consumption of these food products. Deamido-nad(+) exists in all living species, ranging from bacteria to humans. In humans, deamido-nad(+) is involved in few metabolic pathways, which include glutamate metabolism, homocarnosinosis, and nicotinate and nicotinamide metabolism. Deamido-nad(+) is also involved in few metabolic disorders, which include 2-hydroxyglutric aciduria (D and L form), 4-hydroxybutyric aciduria/succinic semialdehyde dehydrogenase deficiency, hyperinsulinism-hyperammonemia syndrome, and succinic semialdehyde dehydrogenase deficiency.
Iminoaspartic acid
D018377 - Neurotransmitter Agents > D018846 - Excitatory Amino Acids Iminoaspartic acid is a substrate for D-aspartate oxidase. [HMDB] Iminoaspartic acid is a substrate for D-aspartate oxidase.
Nicotinamide adenine dinucleotide
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 converted to 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 by cellular respiration. (wikipedia). Nicotinamide adenine dinucleotide is a 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). (Dorland, 27th ed) [HMDB] 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 (Wikipedia). 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) (Dorland, 27th ed). COVID info from COVID-19 Disease Map Corona-virus Coronavirus SARS-CoV-2 COVID-19 SARS-CoV COVID19 SARS2 SARS NAD+ is a coenzyme composed of ribosylnicotinamide 5'-diphosphate coupled to adenosine 5'-phosphate by pyrophosphate linkage. NAD+ is a coenzyme composed of ribosylnicotinamide 5'-diphosphate coupled to adenosine 5'-phosphate by pyrophosphate linkage.
