Guanine is one of the four main nucleobases found in the nucleic acids DNA and RNA, the others being adenine, cytosine, and thymine. In DNA, guanine is paired with cytosine. The guanine nucleoside is called guanosine.
Nucleotides are organic molecules composed of a nitrogenous base, a pentose sugar and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules within all life-forms on Earth. Nucleotides are obtained in the diet and are also synthesized from common nutrients by the liver.
Pyrimidine is an aromatic, heterocyclic, organic compound similar to pyridine. One of the three diazines, it has nitrogen atoms at positions 1 and 3 in the ring. The other diazines are pyrazine and pyridazine.
Uracil is one of the four nucleobases in the nucleic acid RNA. The others are adenine (A), cytosine (C), and guanine (G). In RNA, uracil binds to adenine via two hydrogen bonds. In DNA, the uracil nucleobase is replaced by thymine (T). Uracil is a demethylated form of thymine.
Xanthine oxidase is a form of xanthine oxidoreductase, a type of enzyme that generates reactive oxygen species. These enzymes catalyze the oxidation of hypoxanthine to xanthine and can further catalyze the oxidation of xanthine to uric acid. These enzymes play an important role in the catabolism of purines in some species, including humans.
Nucleic acid metabolism is a collective term that refers to the variety of chemical reactions by which nucleic acids are either synthesized or degraded. Nucleic acids are polymers made up of a variety of monomers called nucleotides. Nucleotide synthesis is an anabolic mechanism generally involving the chemical reaction of phosphate, pentose sugar, and a nitrogenous base. Degradation of nucleic acids is a catabolic reaction and the resulting parts of the nucleotides or nucleobases can be salvaged to recreate new nucleotides. Both synthesis and degradation reactions require multiple enzymes to facilitate the event. Defects or deficiencies in these enzymes can lead to a variety of diseases.
Barbiturase is a zinc-containing amidohydrolase. Its systemic name is barbiturate amidohydrolase (3-oxo-3-ureidopropanoate-forming). Barbiturase acts as a catalyst in the second step of oxidative pyrimidine degradation, promoting the ring-opening hydrolysis of barbituric acid to ureidomalonic acid. Although grouped into the naturally existing amidohydrolases, it demonstrates more homology with cyanuric acid amidohydrolase. Therefore, it has been proposed that barbiturase, along with cyanuric acid, should be grouped into a new family. KEGG
Xanthine dehydrogenase, also known as XDH, is a protein that, in humans, is encoded by the XDH gene.
In enzymology, a 3-hydroxyacyl-CoA dehydrogenase (EC 1.1.1.35) is an enzyme that catalyzes the chemical reaction
In enzymology, a dihydropyrimidine dehydrogenase (NADP+) (EC 1.3.1.2) is an enzyme that catalyzes the chemical reaction
In enzymology, a dihydrouracil dehydrogenase (NAD+) (EC 1.3.1.1) is an enzyme that catalyzes the chemical reaction
Long-chain alcohol oxidase is one of two enzyme classes that oxidize long-chain or fatty alcohols to aldehydes. It has been found in certain Candida yeast, where it participates in omega oxidation of fatty acids to produce acyl-CoA for energy or industrial use, as well as in other fungi, plants, and bacteria.
In enzymology, a thiamine oxidase (EC 1.1.3.23) is an enzyme that catalyzes the chemical reaction
In enzymology, an aldehyde dehydrogenase (NAD+) (EC 1.2.1.3) is an enzyme that catalyzes the chemical reaction
In enzymology, an aminomuconate-semialdehyde dehydrogenase (EC 1.2.1.32) is an enzyme that catalyzes the chemical reaction
In enzymology, a 1-pyrroline-5-carboxylate dehydrogenase (EC 1.2.1.88) is an enzyme that catalyzes the chemical reaction
Uracil dehydrogenase is an enzyme with systematic name uracil:(acceptor) oxidoreductase. This enzyme catalyses the following chemical reaction
Methylsterol monooxygenase (EC 1.14.13.72, methylsterol hydroxylase, 4-methylsterol oxidase, 4,4-dimethyl-5alpha-cholest-7-en-3beta-ol,hydrogen-donor:oxygen oxidoreductase (hydroxylating)) is an enzyme with systematic name 4,4-dimethyl-5alpha-cholest-7-en-3beta-ol,NAD(P)H:oxygen oxidoreductase (hydroxylating). This enzyme catalyses the following chemical reaction
Pyrimidine oxygenase (EC 1.14.99.46, RutA) is an enzyme with systematic name uracil,FMNH2:oxygen oxidoreductase (uracil hydroxylating, ring-opening). This enzyme catalyses the following chemical reaction
Caffeine dehydrogenase, commonly referred to in scientific literature as caffeine oxidase, is an enzyme with the systematic name caffeine:ubiquinone oxidoreductase. The enzyme is most well known for its ability to directly oxidize caffeine, a type of methylxanthine, to trimethyluric acid. Caffeine dehydrogenase can be found in bacterium Pseudomonas sp. CBB1 and in several species within the genera Alcaligenes, Rhodococcus, and Klebsiella.
