nicotinamide-nucleotide adenylyltransferase | |||||||||
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Identifiers | |||||||||
EC no. | 2.7.7.1 | ||||||||
CAS no. | 9032-70-6 | ||||||||
Databases | |||||||||
IntEnz | IntEnz view | ||||||||
BRENDA | BRENDA entry | ||||||||
ExPASy | NiceZyme view | ||||||||
KEGG | KEGG entry | ||||||||
MetaCyc | metabolic pathway | ||||||||
PRIAM | profile | ||||||||
PDB structures | RCSB PDB PDBe PDBsum | ||||||||
Gene Ontology | AmiGO / QuickGO | ||||||||
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In enzymology, nicotinamide-nucleotide adenylyltransferase (NMNAT) (EC 2.7.7.1) are enzymes that catalyzes the chemical reaction
Thus, the two substrates of this enzyme are ATP and nicotinamide mononucleotide (NMN), whereas its two products are diphosphate and NAD+.
This enzyme participates in nicotinate and nicotinamide metabolism.
Humans have three protein isoforms: NMNAT1 (widespread), NMNAT2 (predominantly in brain), and NMNAT3 (highest in liver, heart, skeletal muscle, and erythrocytes). [1] Mutations in the NMNAT1 gene lead to the LCA9 form of Leber congenital amaurosis. [1] Mutations in NMNAT2 or NMNAT3 genes are not known to cause any human disease. [1] NMNAT2 is critical for neurons: loss of NMNAT2 is associated with neurodegeneration. [1] All NMNAT isoforms reportedly decline with age. [2]
This enzyme belongs to the family of transferases, specifically those transferring phosphorus-containing nucleotide groups (nucleotidyltransferases). The systematic name of this enzyme class is ATP:nicotinamide-nucleotide adenylyltransferase. Other names in common use include NAD+ pyrophosphorylase, adenosine triphosphate-nicotinamide mononucleotide transadenylase, ATP:NMN adenylyltransferase, diphosphopyridine nucleotide pyrophosphorylase, nicotinamide adenine dinucleotide pyrophosphorylase, nicotinamide mononucleotide adenylyltransferase, and NMN adenylyltransferase.
As of late 2007, 11 structures have been solved for this class of enzymes, with PDB accession codes 1EJ2, 1GZU, 1HYB, 1KKU, 1KQN, 1KQO, 1KR2, 1M8F, 1M8G, 1M8J, and 1M8K.
The three protein isoforms have the following cellular localizations [3]
Chronic inflammation due to obesity and other causes reduced NMNAT and NAD+ levels in many tissues. [5]
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.
Isocitrate dehydrogenase (NAD+) (EC 1.1.1.41, isocitric dehydrogenase, beta-ketoglutaric-isocitric carboxylase, isocitric acid dehydrogenase, NAD dependent isocitrate dehydrogenase, NAD isocitrate dehydrogenase, NAD-linked isocitrate dehydrogenase, NAD-specific isocitrate dehydrogenase, NAD isocitric dehydrogenase, isocitrate dehydrogenase (NAD), IDH (ambiguous), nicotinamide adenine dinucleotide isocitrate dehydrogenase) is an enzyme with systematic name isocitrate:NAD+ oxidoreductase (decarboxylating). This enzyme catalyses the following chemical reaction
UTP—glucose-1-phosphate uridylyltransferase also known as glucose-1-phosphate uridylyltransferase is an enzyme involved in carbohydrate metabolism. It synthesizes UDP-glucose from glucose-1-phosphate and UTP; i.e.,
NAD+ kinase (EC 2.7.1.23, NADK) is an enzyme that converts nicotinamide adenine dinucleotide (NAD+) into NADP+ through phosphorylating the NAD+ coenzyme. NADP+ is an essential coenzyme that is reduced to NADPH primarily by the pentose phosphate pathway to provide reducing power in biosynthetic processes such as fatty acid biosynthesis and nucleotide synthesis. The structure of the NADK from the archaean Archaeoglobus fulgidus has been determined.
In enzymology, a rubredoxin-NAD+ reductase (EC 1.18.1.1) is an enzyme that catalyzes the chemical reaction.
In enzymology, a NAD(P)H dehydrogenase (quinone) (EC 1.6.5.2) is an enzyme that catalyzes the chemical reaction
In enzymology, a NAD+ synthase (EC 6.3.1.5) is an enzyme that catalyzes the chemical reaction
In enzymology, a NAD+ diphosphatase (EC 3.6.1.22) is an enzyme that catalyzes the chemical reaction
In enzymology, a nucleotide diphosphatase (EC 3.6.1.9) is an enzyme that catalyzes the chemical reaction
Nicotinamide phosphoribosyltransferase, formerly known as pre-B-cell colony-enhancing factor 1 (PBEF1) or visfatin for its extracellular form (eNAMPT), is an enzyme that in humans is encoded by the NAMPT gene. The intracellular form of this protein (iNAMPT) is the rate-limiting enzyme in the nicotinamide adenine dinucleotide (NAD+) salvage pathway that converts nicotinamide to nicotinamide mononucleotide (NMN) which is responsible for most of the NAD+ formation in mammals. iNAMPT can also catalyze the synthesis of NMN from phosphoribosyl pyrophosphate (PRPP) when ATP is present. eNAMPT has been reported to be a cytokine (PBEF) that activates TLR4, that promotes B cell maturation, and that inhibits neutrophil apoptosis.
In enzymology, a nicotinate-nucleotide diphosphorylase (carboxylating) (EC 2.4.2.19) is an enzyme that catalyzes the chemical reaction
In enzymology, a FMN adenylyltransferase is an enzyme that catalyzes the chemical reaction
In enzymology, a nicotinate-nucleotide adenylyltransferase (EC 2.7.7.18) is an enzyme that catalyzes the chemical reaction
Nicotinamide mononucleotide adenylyltransferase 1 (NMNAT1) is an enzyme that in humans is encoded by the nmnat1 gene. It is a member of the nicotinamide-nucleotide adenylyltransferases (NMNATs) which catalyze nicotinamide adenine dinucleotide (NAD) synthesis.
Nicotinamide mononucleotide adenylyltransferase 2 (NMNAT2) is an enzyme that in humans is encoded by the NMNAT2 gene.
Nicotinamide riboside (NR, SR647) is a pyridine-nucleoside and a form of vitamin B3. It functions as a precursor to nicotinamide adenine dinucleotide, or NAD+, through a two-step and a three-step pathway.
The Nicotinamide Ribonucleoside (NR) Uptake Permease (PnuC) Family is a family of transmembrane transporters that is part of the TOG superfamily. Close PnuC homologues are found in a wide range of Gram-negative and Gram-positive bacteria, archaea and eukaryotes.
Nicotinamide mononucleotide is a nucleotide derived from ribose, nicotinamide, nicotinamide riboside and niacin. In humans, several enzymes use NMN to generate nicotinamide adenine dinucleotide (NADH). In mice, it has been proposed that NMN is absorbed via the small intestine within 10 minutes of oral uptake and converted to nicotinamide adenine dinucleotide (NAD+) through the Slc12a8 transporter. However, this observation has been challenged, and the matter remains unsettled.
Nicotinamide mononucleotide adenylyltransferase 3 (NMNAT3) is an enzyme that in humans is encoded by the NMNAT3 gene.
Sterile alpha and TIR motif containing 1 Is an enzyme that in humans is encoded by the SARM1 gene. It is the most evolutionarily conserved member of the Toll/Interleukin receptor-1 (TIR) family. SARM1's TIR domain has intrinsic NADase enzymatic activity that is highly conserved from archaea, plants, nematode worms, fruit flies, and humans. In mammals, SARM1 is highly expressed in neurons, where it resides in both cell bodies and axons, and can be associated with mitochondria.