Coenzyme in the context of "Vitamin B6"

Adenosine triphosphate (ATP) is a nucleoside triphosphate that provides energy of approximate 30.5kJ/mol to drive and support many processes in living cells, such as muscle contraction, nerve impulse propagation, and chemical synthesis. Found in all known forms of life, it is often referred to as the "molecular unit of currency" for intracellular energy transfer.

When consumed in a metabolic process, ATP converts either to adenosine diphosphate (ADP) or to adenosine monophosphate (AMP). Other processes regenerate ATP. It is also a precursor to DNA and RNA, and is used as a coenzyme. An average adult human processes around 50 kilograms (about 100 moles) daily.

A carbohydrate (/ˌkɑːrboʊˈhaɪdreɪt/) is a sugar (saccharide) or a sugar derivative. For the simplest carbohydrates, the carbon-to-hydrogen-to-oxygen atomic ratio is 1:2:1, i.e. they are often represented by the empirical formula C(H₂O)_n. Together with amino acids, fats, and nucleic acids, the carbohydrates are one of the major families of biomolecules.

Carbohydrates perform numerous roles in living organisms. Polysaccharides serve as an energy store (e.g., starch and glycogen) and as structural components (e.g., cellulose in plants and chitin in arthropods and fungi). The 5-carbon monosaccharide ribose is an important component of coenzymes (e.g., ATP, FAD and NAD) and the backbone of the genetic molecule known as RNA. The related deoxyribose is a component of DNA. Saccharides and their derivatives play key roles in the immune system, fertilization, preventing pathogenesis, blood clotting, and development.

Alexander Robertus Todd, Baron Todd (2 October 1907 – 10 January 1997) was a British biochemist whose research on the structure and synthesis of nucleotides, nucleosides, and nucleotide coenzymes gained him the Nobel Prize for Chemistry in 1957.

In biochemistry, flavin adenine dinucleotide (FAD) is a redox-active coenzyme associated with various proteins, which is involved with several enzymatic reactions in metabolism. A flavoprotein is a protein that contains a flavin group, which may be in the form of FAD or flavin mononucleotide (FMN). Many flavoproteins are known: components of the succinate dehydrogenase complex, α-ketoglutarate dehydrogenase, and a component of the pyruvate dehydrogenase complex.

FAD exists in two common oxidation states, the fully oxidized form (FAD) and the fully reduced, dihydrogenated form, FADH₂. Other oxidation states also exist, including the N-oxide and semiquinone states. FAD, in its fully oxidized form, accepts two electrons and two protons to become FADH₂. The semiquinone (FADH) can be formed by either reduction of FAD or oxidation of FADH₂ by accepting or donating one electron and one proton, respectively. Some proteins, however, generate and maintain a superoxidized form of the flavin cofactor, the flavin-N(5)-oxide.

Coenzyme A (CoA, SHCoA, CoASH) is a coenzyme, notable for its role in the synthesis and oxidation of fatty acids, and the oxidation of pyruvate in the citric acid cycle. All genomes sequenced to date encode enzymes that use coenzyme A as a substrate, and around 4% of cellular enzymes use it (or a thioester) as a substrate. In humans, CoA biosynthesis requires cysteine, pantothenate (vitamin B₅), and adenosine triphosphate (ATP).

In its acetyl form, coenzyme A is a highly versatile molecule, serving metabolic functions in both the anabolic and catabolic pathways. Acetyl-CoA is utilised in the post-translational regulation and allosteric regulation of pyruvate dehydrogenase and carboxylase to maintain and support the partition of pyruvate synthesis and degradation.

A carbohydrate (/ˌkɑːrboʊˈhaɪdreɪt/) is a sugar (saccharide) or a sugar derivative. For the simplest carbohydrates, the carbon-to-hydrogen-to-oxygen atomic ratio is 1:2:1, i.e. they are often represented by the empirical formula (CH₂O)_n. Together with amino acids, fats, and nucleic acids, the carbohydrates are one of the major families of biomolecules.

Carbohydrates perform numerous roles in living organisms. Polysaccharides serve as an energy store (e.g., starch and glycogen) and as structural components (e.g., cellulose in plants and chitin in arthropods and fungi). The 5-carbon monosaccharide ribose is an important component of coenzymes (e.g., ATP, FAD and NAD) and the backbone of the genetic molecule known as RNA. The related deoxyribose is a component of DNA. Saccharides and their derivatives play key roles in the immune system, fertilization, preventing pathogenesis, blood clotting, and development.