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 (IDH) (EC 1.1.1.42) and (EC 1.1.1.41) is an enzyme that catalyzes the oxidative decarboxylation of isocitrate, producing alpha-ketoglutarate (α-ketoglutarate) and CO2. This is a two-step process, which involves oxidation of isocitrate (a secondary alcohol) to oxalosuccinate (a ketone), followed by the decarboxylation of the carboxyl group beta to the ketone, forming alpha-ketoglutarate. In humans, IDH exists in three isoforms: IDH3 catalyzes the third step of the citric acid cycle while converting NAD+ to NADH in the mitochondria. The isoforms IDH1 and IDH2 catalyze the same reaction outside the context of the citric acid cycle and use NADP+ as a cofactor instead of NAD+. They localize to the cytosol as well as the mitochondrion and peroxisome.
In enzymology, aldose reductase is a cytosolic NADPH-dependent oxidoreductase that catalyzes the reduction of a variety of aldehydes and carbonyls, including monosaccharides. It is primarily known for catalyzing the reduction of glucose to sorbitol, the first step in polyol pathway of glucose metabolism.
In enzymology, a hydroxymethylglutaryl-CoA reductase (NADPH) (EC 1.1.1.34) is an enzyme that catalyzes the chemical reaction
In enzymology, a tetrahydroxynaphthalene reductase (EC 1.1.1.252) is an enzyme that catalyzes the chemical reaction
In enzymology, a 1,5-anhydro-D-fructose reductase (1,5-anhydro-D-mannitol-forming) (EC 1.1.1.292) is an enzyme that catalyzes the chemical reaction
In enzymology, a 3alpha(or 20beta)-hydroxysteroid dehydrogenase (EC 1.1.1.53) is an enzyme that catalyzes the chemical reaction
In enzymology, a 8-oxocoformycin reductase (EC 1.1.1.235) is an enzyme that catalyzes the chemical reaction
In enzymology, a long-chain-fatty-acyl-CoA reductase (EC 1.2.1.50) is an enzyme that catalyzes the chemical reaction
In enzymology, a mycothiol-dependent formaldehyde dehydrogenase (EC 1.1.1.306) is an enzyme that catalyzes the chemical reaction
In enzymology, a rubredoxin—NAD(P)+ reductase (EC 1.18.1.4) is an enzyme that catalyzes the chemical reaction
In enzymology, 6,7-dihydropteridine reductase (EC 1.5.1.34, also Dihydrobiopterin reductase) is an enzyme that catalyzes the chemical reaction
In enzymology, a CoA-disulfide reductase (EC 1.8.1.14) is an enzyme that catalyzes the chemical reaction
In enzymology, an FMN reductase (EC 1.5.1.29) 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
Sulfite reductases (EC 1.8.99.1) are enzymes that participate in sulfur metabolism. They catalyze the reduction of sulfite to hydrogen sulfide and water. Electrons for the reaction are provided by a dissociable molecule of either NADPH, bound flavins, or ferredoxins.
In enzymology, a trypanothione-disulfide reductase (EC 1.8.1.12) is an enzyme that catalyzes the chemical reaction
In enzymology, a 2-isopropylmalate synthase (EC 2.3.3.13) is an enzyme that catalyzes the chemical reaction
Mycothiol is an unusual thiol compound found in the Actinomycetota. It is composed of a cysteine residue with an acetylated amino group linked to glucosamine, which is then linked to inositol. The oxidized, disulfide form of mycothiol (MSSM) is called mycothione, and is reduced to mycothiol by the flavoprotein mycothione reductase. Mycothiol biosynthesis and mycothiol-dependent enzymes such as mycothiol-dependent formaldehyde dehydrogenase and mycothione reductase have been proposed to be good drug targets for the development of treatments for tuberculosis.
L-cysteine:1D-myo-inositol 2-amino-2-deoxy-alpha-D-glucopyranoside ligase is an enzyme with systematic name L-cysteine:1-O-(2-amino-2-deoxy-alpha-D-glucopyranosyl)-1D-myo-inositol ligase (AMP-forming). This enzyme catalyses the following chemical reaction
