Coenzyme

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Coenzyme

Many enzymes require a cofactor

Cofactor (biochemistry)

A cofactor is a non-protein chemical compound that is bound to an enzyme and is required for catalysis. They can be considered "helper molecules/ions" that assist in biochemical transformations....
for catalytic activity, accelerating the transformation of a specific substrate to a particular product. The inactive protein, without the cofactor is called an apoenzyme, while the complete enzyme with cofactor is the holoenzyme. The cofactor can be either a coenzyme or a metal ion (usually Mg²⁺, Cu⁺, Mn²⁺ for instance). A coenzyme is a small organic molecule (typically a molecular mass less than 1000 Da) that directly participates in the enzyme reaction.

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Many enzymes require a cofactor

Cofactor (biochemistry)

Prosthetic group

A prosthetic group is a non-protein component of a conjugated protein that is required for the protein's biological activity. The prosthetic group may be organic compound or inorganic ....
. It is important to emphasize that there is no sharp division between loosely and tightly bound coenzymes. Indeed, a typical coenzyme like NAD⁺ can be tightly bound in some enzyme, while it is loosely bound in others. Thiamine diphosphate (ThDP) is tightly bound in transketolase

Transketolase

Transketolase, an enzyme of both the pentose phosphate pathway in animals and the Calvin cycle of photosynthesis, catalyzes two important reactions, which operate in opposite directions in these two pathways....
or pyruvate decarboxylase

Pyruvate decarboxylase

Pyruvate decarboxylase is a homotetrameric enzyme that catalysis the decarboxylation of pyruvic acid to acetaldehyde and carbon dioxide. It is also called 2-oxo-acid carboxylase, alpha-ketoacid carboxylase, and pyruvic decarboxylase....
, while it is less tightly bound in pyruvate dehydrogenase

Pyruvate dehydrogenase

Pyruvate dehydrogenase complex is a complex of three enzymes that transform pyruvate into acetyl-CoA by a process called pyruvate decarboxylation....
. Other coenzymes, flavin adenine dinucleotide (FAD), biotin

Biotin

Biotin, also known as vitamin H or B7, has the chemical formula C10H16N2O3S , is a water-soluble B-complex vitamin which is composed of an ureido ring fused with a tetrahydrothiophene ring....
or lipoamide

Lipoamide

Lipoamide is a trivial name for 6,8-dithiooctanoic amide. It is lipoic acid's functional form where the carboxyl group is attached to protein by an amide linkage to an amino acid....
for instance, are covalently bound. Tightly bound coenzymes are generally regenerated during the same reaction cycle, while loosely bound coenzymes can be regenerated in a subsequent reaction catalyzed by a different enzyme. In the latter case, the coenzyme can also be considered a substrate or cosubstrate.

Some enzymes or enzyme complexes require several cofactors. A good example is the multienzyme complex pyruvate dehydrogenase

Pyruvate dehydrogenase

Pyruvate dehydrogenase complex is a complex of three enzymes that transform pyruvate into acetyl-CoA by a process called pyruvate decarboxylation....
. This enzyme complex at the junction of glycolysis and the citric acid cycle requires five coenzymes and one metal ion : loosely bound thiamine diphosphate (ThDP), covalently bound lipoamide

Lipoamide

Nicotinamide adenine dinucleotide

Coenzyme A

Coenzyme A is a coenzyme, notable for its role in the Fatty acid metabolism#Synthesis and Fatty acid metabolism#.CE.B2-Oxidation of fatty acids, and the oxidation of pyruvic acid in the citric acid cycle....
(CoA) and a metal ion (Mg²⁺).

In the metabolism

Metabolism

Metabolism is the set of chemical reactions that occur in living organisms in order to maintain life. These processes allow organisms to grow and reproduce, maintain their structures, and respond to their environments....
, coenzymes play the role of carriers, in both group-transfer reactions (organaic radicals or phosphates), for example coenzyme A

Coenzyme A

Adenosine triphosphate

This article is about the chemical used by cells as an energy carrier. For other uses, see ATP .Adenosine-5'-triphosphate is a multifunctional nucleotide, and plays an important role in cell biology as a coenzyme that is the "molecule unit of currency" of intracellular energy transfer....
(ATP), and redox reactions, such as coenzyme Q₁₀, flavin adenine dinucleotide (FAD) and nicotinamide adenine dinucleotide

Nicotinamide adenine dinucleotide

Nicotinamide adenine dinucleotide, abbreviated NAD+, is a coenzyme found in all living cell s. The compound is a dinucleotide, since it consists of two nucleotides joined through their phosphate groups: with one nucleotide containing an adenine base, and the other containing nicotinamide....
(NAD⁺). Coenzymes are consumed and recycled continuously in metabolism, with one set of enzymes adding a chemical group to the coenzyme and another set removing it. For example, enzymes such as ATP synthase

ATP synthase

An ATP synthase is a general term for an enzyme that can synthesize adenosine triphosphate from adenosine diphosphate and inorganic phosphate by using some form of energy....
continuously phosphorylate

Phosphorylation

Phosphorylation is the addition of a phosphate group to a protein or other organic molecule. Protein phosphorylation in particular plays a significant role in a wide range of cellular processes....
adenosine diphosphate

Adenosine diphosphate

Adenosine diphosphate, abbreviated ADP, is a nucleotide. It is an ester of pyrophosphoric acid with the nucleoside adenosine. ADP consists of the pyrophosphate Functional group, the pentose sugar ribose, and the nucleobase adenine....
(ADP), converting it into ATP, while enzymes such as kinase

Kinase

In chemistry and biochemistry, a kinase, alternatively known as a phosphotransferase, is a type of enzyme that transfers phosphate groups from High-energy phosphate donor molecules, such as adenosine triphosphate, to specific target molecules ; the process is termed phosphorylation ...
s dephosphorylate the ATP and convert it back to ADP.

Coenzymes molecules are often vitamin

Vitamin

A vitamin is an organic compound required as a nutrient in tiny amounts by an organism. A compound is called a vitamin when it cannot be biosynthesis in sufficient quantities by an organism, and must be obtained from the diet....
s or are made from vitamins. Many coenzymes contain the nucleotide

Nucleotide

Nucleotides are molecules that comprise the structural units of RNA and DNA. Additionally, nucleotides play central roles in metabolism. In that capacity, they serve as sources of chemical energy , participate in cell signaling , and are incorporated into important cofactors of enzymatic reactions ....
adenosine monophosphate

Adenosine monophosphate

Adenosine monophosphate , also known as 5'-adenylic acid, is a nucleotide that is found in RNA. It is an ester of phosphoric acid and the nucleoside adenosine....
(AMP) as part of their structures, such as ATP

Adenosine triphosphate

Coenzyme A

Coenzyme A is a coenzyme, notable for its role in the Fatty acid metabolism#Synthesis and Fatty acid metabolism#.CE.B2-Oxidation of fatty acids, and the oxidation of pyruvic acid in the citric acid cycle....
, FAD and NAD⁺. This common structure may reflect a common evolutionary origin as part of ribozyme

Ribozyme

A ribozyme is an RNA molecule that catalyzes a chemical reaction. Many natural ribozymes catalyze either the hydrolysis of one of their own phosphodiester bonds, or the hydrolysis of bonds in other RNAs, but they have also been found to catalyze the aminotransferase activity of the ribosome....
s in an ancient RNA world. It has been suggested that the AMP part of the molecule can be considered a kind a "handle" by which the enzyme can "grasp" the coenzyme to switch it between different catalytic centers.

Definition

The terms cofactor, coenzyme and prosthetic group represent three different, though sometimes overlapping concepts. The terms cofactor (the more general term) and coenzyme (organic molecule) refer to enzymes and as such to the functional properties of a protein. On the other hand "prosthetic group", emphasizes the nature of the binding (tight or covalent) and thus refers to a structural property. For instance, you would not call the sugar moiety of a glycoprotein, a cofactor, as it has no enzymatic activity. On the other hand, the covalently bound coenzyme FAD is a prosthetic group, while the generally loosely bound coenzyme NAD⁺ is a coenzyme but not a prosthetic group. Different sources give slightly different definitions of coenzymes, cofactors and prosthetic groups. Some consider tightly-bound organic molecules as prosthetic groups and not as coenzymes, while others define all non-protein organic molecules needed for enzyme activity as coenzymes, and classify those that are tightly bound as coenzyme prosthetic groups. Unsurprisingly, these terms are often used loosely.

A 1979 letter in Trends in Biochemical Sciences noted the confusion in the literature and the essentially arbitrary distinction made between prosthetic groups and coenzymes and proposed the following scheme. Here, cofactors were defined as an additional substance apart from protein and substrate that is required for enzyme activity and a prosthetic group as a substance that undergoes its whole catalytic cycle attached to a single enzyme molecule. However, the author could not arrive at a single all-encompassing definition of a "coenzyme" and proposed that this term be dropped from use in the literature.

Coenzymes as metabolic intermediates

Metabolism involves a vast array of chemical reactions, but most fall under a few basic types of reactions that involve the transfer of functional group

Functional group

In organic chemistry, functional groups are specific groups of atoms within molecules that are responsible for the characteristic chemical reactions of those molecules....
s. This common chemistry allows cells to use a small set of metabolic intermediates to carry chemical groups between different reactions. These group-transfer intermediates are the coenzymes.

Each class of group-transfer reaction is carried out by a particular coenzyme, which is the substrate for a set of enzymes that produce it, and a set of enzymes that consume it. An example of this are the dehydrogenase

Dehydrogenase

A dehydrogenase is an enzyme that oxidizes a substrate by transferring one or more hydrides to an acceptor, usually Nicotinamide adenine dinucleotide/NADP or a flavin coenzyme such as FAD or FMN....
s that use nicotinamide adenine dinucleotide

Nicotinamide adenine dinucleotide

Nicotinamide adenine dinucleotide, abbreviated NAD+, is a coenzyme found in all living cell s. The compound is a dinucleotide, since it consists of two nucleotides joined through their phosphate groups: with one nucleotide containing an adenine base, and the other containing nicotinamide....
(NAD⁺) as a cofactor. Here, hundreds of separate types of enzymes remove electrons from their substrates and reduce

Redox

Redox describes all chemical reactions in which atoms have their oxidation number changed.This can be either a simple redox process such as the oxidation of carbon to yield carbon dioxide or the reduction of carbon by hydrogen to yield methane , or it can be a complex process such as the oxidation of sugar in the human body through a ser...
NAD⁺ to NADH. This reduced coenzyme is then a substrate for any of the reductase

Reductase

A reductase is an enzyme which lowers the activation energy for a Redox. ...
s in the cell that need to reduce their substrates.

Coenzymes are therefore continuously recycled as part of metabolism. As an example, the total quantity of ATP in the human body is about 0.1 mole

Mole (unit)

The mole is a Units of measurement of amount of substance: it is an SI base unit, and one of the few units used to measure this physical quantity....
. This ATP is constantly being broken down into ADP, and then converted back into ATP. Thus, at any given time, the total amount of ATP + ADP remains fairly constant. The energy used by human cells requires the hydrolysis

Hydrolysis

Hydrolysis is a chemical reaction during which one or more water are split into hydrogen and hydroxide ions which may go on to participate in further reactions....
of 100 to 150 moles of ATP daily which is around 50 to 75 kg. Typically, a human will use up their body weight of ATP over the course of the day. This means that each ATP molecule is recycled 1000 to 1500 times daily.

Types

Acting as coenzymes in organisms is the major role of vitamin

Vitamin

A vitamin is an organic compound required as a nutrient in tiny amounts by an organism. A compound is called a vitamin when it cannot be biosynthesis in sufficient quantities by an organism, and must be obtained from the diet....
s, although vitamins do have other functions in the body. Many coenzymes also contain a nucleotide

Nucleotide

Coenzyme A

Acyl

An acyl group is a functional group derived by the removal of one or more hydroxyl groups from an oxoacid.. In organic chemistry, the acyl group is usually derived from a carboxylic acid of the form RCarbon Oxygen hydroxyl....
groups. Most coenzymes are found in a huge variety of species, and some are universal to all forms of life. An exception to this wide distribution is a group of unique coenzymes that evolved in methanogen

Methanogen

Methanogens are archaea that produce methane as a metabolic byproduct in anoxic conditions. They are common in wetlands, where they are responsible for marsh gas, and in the guts of animals such as ruminants and humans, where they are responsible for the methane content of flatulence....
s, which are restricted to this group of archaea

Archaea

The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon . Archaea, like bacteria, are prokaryotic....
.

Vitamins and derivatives

Coenzyme	Vitamin	Additional component	Chemical group(s) transferred	Distribution
Thiamine diphosphate	Thiamine Thiamine 'Thiamine', or 'thiamin', sometimes called aneurin, is a water-soluble vitamin of the B complex , whose phosphate derivatives are involved in many cellular processes.... (B₁)	None	2-carbon groups, a cleavage	Bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... , archaea Archaea The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon . Archaea, like bacteria, are prokaryotic.... and eukaryote Eukaryote Animals, plants, fungus, and protists are eukaryotes , organisms whose Cell are organized into complex structures enclosed within Cell membrane.... s \|- \| NAD⁺ Nicotinamide adenine dinucleotide Nicotinamide adenine dinucleotide, abbreviated NAD+, is a coenzyme found in all living cell s. The compound is a dinucleotide, since it consists of two nucleotides joined through their phosphate groups: with one nucleotide containing an adenine base, and the other containing nicotinamide.... and NADP⁺ Nicotinamide adenine dinucleotide phosphate Nicotinamide adenine dinucleotide phosphate is used in anabolic reactions, such as lipid and nucleic acid synthesis, which require NADPH as a reducing agent....	Niacin Niacin Niacin, also known as vitamin B3, is a water-soluble vitamin which prevents the Nutrition disorder pellagra. It is an organic compound with the chemical formula C6H5NO2.... (B₃)	ADP	Electron Electron The electron is a subatomic particle that carries a negative electric charge. It has elementary particle and is believed to be a point particle.... s	Bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... , archaea Archaea The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon . Archaea, like bacteria, are prokaryotic.... and eukaryote Eukaryote Animals, plants, fungus, and protists are eukaryotes , organisms whose Cell are organized into complex structures enclosed within Cell membrane.... s \|- \| Pyridoxal phosphate	Pyridoxine Pyridoxine Pyridoxine is one of the compounds that can be called vitamin B6, along with Pyridoxal and Pyridoxamine. It differs from pyridoxamine by the substituent at the '4' position.... (B₆)	None	amino groups	Bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... , archaea Archaea The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon . Archaea, like bacteria, are prokaryotic.... and eukaryote Eukaryote Animals, plants, fungus, and protists are eukaryotes , organisms whose Cell are organized into complex structures enclosed within Cell membrane.... s \|-	Lipoamide Lipoamide Lipoamide is a trivial name for 6,8-dithiooctanoic amide. It is lipoic acid's functional form where the carboxyl group is attached to protein by an amide linkage to an amino acid....	Lipoic acid Lipoic acid Lipoic acid is an organic compound, one enantiomer of which is an essential cofactor for many enzyme complexes. The molecule consists of a carboxylic acid and a cyclic Disulfide bond....	None	electrons, acyl groups Acyl An acyl group is a functional group derived by the removal of one or more hydroxyl groups from an oxoacid.. In organic chemistry, the acyl group is usually derived from a carboxylic acid of the form RCarbon Oxygen hydroxyl....	Bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... , archaea Archaea The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon . Archaea, like bacteria, are prokaryotic.... and eukaryote Eukaryote Animals, plants, fungus, and protists are eukaryotes , organisms whose Cell are organized into complex structures enclosed within Cell membrane.... s \|-	Cobalamine	Cobalamine (B₁₂)	None	hydrogen Hydrogen Hydrogen is the chemical element with atomic number 1. It is represented by the chemical symbol H. At standard temperature and pressure, hydrogen is a colorless, odorless, nonmetallic, tasteless, highly combustion and explosive Diatomic molecule gas with the molecular formula H2.... , alkyl groups Alkyl An alkyl is a univalent Radical consisting of carbon and hydrogen atoms, arranged in a chain. The Alkyls form homologous series with the general formula CnH2n+1....	Bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... , archaea Archaea The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon . Archaea, like bacteria, are prokaryotic.... and eukaryote Eukaryote Animals, plants, fungus, and protists are eukaryotes , organisms whose Cell are organized into complex structures enclosed within Cell membrane.... s \|- \| Biotin Biotin Biotin, also known as vitamin H or B7, has the chemical formula C10H16N2O3S , is a water-soluble B-complex vitamin which is composed of an ureido ring fused with a tetrahydrothiophene ring....	Biotin Biotin Biotin, also known as vitamin H or B7, has the chemical formula C10H16N2O3S , is a water-soluble B-complex vitamin which is composed of an ureido ring fused with a tetrahydrothiophene ring.... (H)	None	CO₂	Bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... , archaea Archaea The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon . Archaea, like bacteria, are prokaryotic.... and eukaryote Eukaryote Animals, plants, fungus, and protists are eukaryotes , organisms whose Cell are organized into complex structures enclosed within Cell membrane.... s \|- \| Coenzyme A Coenzyme A Coenzyme A is a coenzyme, notable for its role in the Fatty acid metabolism#Synthesis and Fatty acid metabolism#.CE.B2-Oxidation of fatty acids, and the oxidation of pyruvic acid in the citric acid cycle....	Pantothenic acid Pantothenic acid Pantothenic acid, also called vitamin B5 , is a water-soluble vitamin required to sustain life . Pantothenic acid is needed to form coenzyme-A , and is critical in the metabolism and synthesis of carbohydrates, proteins, and fats.... (B₅)	ADP	Acetyl group Acetyl In organic chemistry, acetyl , is a functional group, the acyl of acetic acid, with chemical formula -CarbonOxygenCarbonHydrogen3. It is sometimes abbreviated as Ac .... and other acyl groups Acyl An acyl group is a functional group derived by the removal of one or more hydroxyl groups from an oxoacid.. In organic chemistry, the acyl group is usually derived from a carboxylic acid of the form RCarbon Oxygen hydroxyl....	Bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... , archaea Archaea The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon . Archaea, like bacteria, are prokaryotic.... and eukaryote Eukaryote Animals, plants, fungus, and protists are eukaryotes , organisms whose Cell are organized into complex structures enclosed within Cell membrane.... s \|- \| Tetrahydrofolic acid Tetrahydrofolic acid Tetrahydrofolic acid is a folic acid derivative....	Folic acid Folic acid Folic acid and Folate are forms of the water-soluble B vitamins. Vitamin B9 is essential to numerous bodily functions ranging from nucleotide synthesis to the remethylation of homocysteine.... (B₉)	Glutamate Glutamic acid Glutamic acid is one of the 20 proteinogenic amino acids and its codons are GAA and GAG. It is a non-essential amino acid. The carboxylate anions and salt of glutamic acid are known as glutamates.... residues	Methyl, formyl Aldehyde An aldehyde is an organic compound containing a terminal carbonyl group. This functional group, which consists of a carbon atom bonded to a hydrogen atom and double bond to an oxygen atom , is called the aldehyde group.... , methylene Methylene Methylene is the chemical species, R2C:, named after methane, in which two of the carbon atom's valence electrons form no bonds. The word is applicable to:... and formimino groups	Bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... , archaea Archaea The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon . Archaea, like bacteria, are prokaryotic.... and eukaryote Eukaryote Animals, plants, fungus, and protists are eukaryotes , organisms whose Cell are organized into complex structures enclosed within Cell membrane.... s \|- \|Menaquinone Vitamin K Vitamin K denotes a group of lipophilic, hydrophobic vitamins that are needed for the posttranslational modification of certain proteins, mostly required for blood coagulation....	Vitamin K	None	Carbonyl group Carbonyl In organic chemistry, a carbonyl group is a functional group composed of a carbon atom double bond to an oxygen atom : C=O.The term carbonyl can also refer to carbon monoxide as a ligand in an inorganic or organometallic complex ; in this situation, carbon is triple-bonded to oxygen : C=O.... and electron Electron The electron is a subatomic particle that carries a negative electric charge. It has elementary particle and is believed to be a point particle.... s	Bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... , archaea Archaea The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon . Archaea, like bacteria, are prokaryotic.... and eukaryote Eukaryote Animals, plants, fungus, and protists are eukaryotes , organisms whose Cell are organized into complex structures enclosed within Cell membrane.... s \|- \|Ascorbic acid Ascorbic acid Ascorbic acid is a sugar acid with antioxidant properties. Its appearance is white to light-yellow crystals or powder. It is water-soluble. The L-enantiomer of ascorbic acid is commonly known as vitamin C....	Vitamin C	None	Electron Electron The electron is a subatomic particle that carries a negative electric charge. It has elementary particle and is believed to be a point particle.... s	Bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... , archaea Archaea The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon . Archaea, like bacteria, are prokaryotic.... and eukaryote Eukaryote Animals, plants, fungus, and protists are eukaryotes , organisms whose Cell are organized into complex structures enclosed within Cell membrane.... s \|- \|FAD	Riboflavin Riboflavin Riboflavin , also known as vitamin B2, is an easily absorbed micronutrient with a key role in maintaining health in humans and animals.... (B₂)	None	Electron Electron The electron is a subatomic particle that carries a negative electric charge. It has elementary particle and is believed to be a point particle.... s	Bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... , archaea Archaea The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon . Archaea, like bacteria, are prokaryotic.... and eukaryote Eukaryote Animals, plants, fungus, and protists are eukaryotes , organisms whose Cell are organized into complex structures enclosed within Cell membrane.... s \|- \|Coenzyme F420 Coenzyme F420 Coenzyme F420 or 8-hydroxy-5-deazaflavin is a coenzyme involved in redox reactions in methanogens. It is a flavin derivative. The coenzyme is a substrate for coenzyme F420 hydrogenase, 5,10-methylenetetrahydromethanopterin reductase and methylenetetrahydromethanopterin dehydrogenase....	Riboflavin Riboflavin Riboflavin , also known as vitamin B2, is an easily absorbed micronutrient with a key role in maintaining health in humans and animals.... (B₂)	Amino acids	Electron Electron The electron is a subatomic particle that carries a negative electric charge. It has elementary particle and is believed to be a point particle.... s	Methanogen Methanogen Methanogens are archaea that produce methane as a metabolic byproduct in anoxic conditions. They are common in wetlands, where they are responsible for marsh gas, and in the guts of animals such as ruminants and humans, where they are responsible for the methane content of flatulence.... s and some bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... \|-

Non-vitamins

Coenzyme	Chemical group(s) transferred	Distribution >- \|Adenosine triphosphate Adenosine triphosphate This article is about the chemical used by cells as an energy carrier. For other uses, see ATP .Adenosine-5'-triphosphate is a multifunctional nucleotide, and plays an important role in cell biology as a coenzyme that is the "molecule unit of currency" of intracellular energy transfer....	Phosphate group Phosphate A phosphate, an inorganic chemical, is a Salt of phosphoric acid. Inorganic phosphates are mining to obtain phosphorus for use in agriculture and industry....	Bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... , archaea Archaea The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon . Archaea, like bacteria, are prokaryotic.... and eukaryote Eukaryote Animals, plants, fungus, and protists are eukaryotes , organisms whose Cell are organized into complex structures enclosed within Cell membrane.... s \|- \|S-Adenosyl methionine S-Adenosyl methionine S-Adenosyl methionine is a coenzyme involved in methyl group transfers. SAM was first discovered in Italy by G. L. Cantoni in 1952. It is made from adenosine triphosphate and methionine by methionine adenosyltransferase ....	Methyl group Methyl group In chemistry, a methyl group is a hydrophobic alkyl functional group named after methane . It has the chemical formula -3 and is often abbreviated -Me....	Bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... , archaea Archaea The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon . Archaea, like bacteria, are prokaryotic.... and eukaryote Eukaryote Animals, plants, fungus, and protists are eukaryotes , organisms whose Cell are organized into complex structures enclosed within Cell membrane.... s \|- \|3'-Phosphoadenosine-5'-phosphosulfate 3'-Phosphoadenosine-5'-phosphosulfate 3'-Phosphoadenosine-5'-phosphosulfate is a specific type of adenosine that is phosphorylated at the 3' and 5' positions, with an additional sulfate group on the 5' phosphate....	Sulfate group Sulfate In inorganic chemistry, a sulfate is a salt of sulfuric acid....	Bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... , archaea Archaea The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon . Archaea, like bacteria, are prokaryotic.... and eukaryote Eukaryote Animals, plants, fungus, and protists are eukaryotes , organisms whose Cell are organized into complex structures enclosed within Cell membrane.... s \|- \| Coenzyme Q Coenzyme Q Coenzyme Q10 is a benzoquinone, where Q refers to the quinone chemical group, and 10 refers to the isoprene chemical subunits....	Electron Electron The electron is a subatomic particle that carries a negative electric charge. It has elementary particle and is believed to be a point particle.... s	Bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... , archaea Archaea The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon . Archaea, like bacteria, are prokaryotic.... and eukaryote Eukaryote Animals, plants, fungus, and protists are eukaryotes , organisms whose Cell are organized into complex structures enclosed within Cell membrane.... s \|- \|Tetrahydrobiopterin Tetrahydrobiopterin Tetrahydrobiopterin, sapropterin, or BH4 is a naturally occurring essential Cofactor of the three aromatic amino acid hydroxylases;phenylalanine hydroxylase for conversion of phenylalanine to tyrosine, tyrosine-3-hydroxylase for the conversion of tyrosine to L-dopa, and tryptophan-5-hydroxylase for the conversion of...	Oxygen Oxygen Oxygen no O2 produced; 2) O2 produced, but absorbed in oceans & seabed rock; 3) O2 starts to gas out of the oceans, but is absorbed by land surfaces and formation of ozone layer; 4-5) O2 sinks filled and the gas accumulates]]... atom and electron Electron The electron is a subatomic particle that carries a negative electric charge. It has elementary particle and is believed to be a point particle.... s	Bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... , archaea Archaea The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon . Archaea, like bacteria, are prokaryotic.... and eukaryote Eukaryote Animals, plants, fungus, and protists are eukaryotes , organisms whose Cell are organized into complex structures enclosed within Cell membrane.... s \|- \|Cytidine triphosphate Cytidine triphosphate Cytidine triphosphate is a pyrimidine nucleotide.CTP is a Substrate in the synthesis of RNA.CTP is a high-energy molecule equal to adenosine triphosphate, but its role in the organism is more specific than that of ATP....	Diacylglycerols and lipid head groups	Bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... , archaea Archaea The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon . Archaea, like bacteria, are prokaryotic.... and eukaryote Eukaryote Animals, plants, fungus, and protists are eukaryotes , organisms whose Cell are organized into complex structures enclosed within Cell membrane.... s \|- \|Nucleotide sugar Nucleotide sugar Nucleotide sugars are biochemicals that act as donors of sugar residues in nucleotide sugars metabolism. They are substrates for glycosyltransferases.... s	Monosaccharide Monosaccharide Monosaccharides are the most basic unit of carbohydrates. They are the simplest form of sugar and are usually colorless, water-soluble, crystal solids.... s	Bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... , archaea Archaea The Archaea are a group of single-celled microorganisms. A single individual or species from this domain is called an archaeon . Archaea, like bacteria, are prokaryotic.... and eukaryote Eukaryote Animals, plants, fungus, and protists are eukaryotes , organisms whose Cell are organized into complex structures enclosed within Cell membrane.... s \|- \|Glutathione Glutathione Glutathione is a tripeptide. It contains an unusual peptide linkage between the amino acid of cysteine and the carboxyl group of the glutamate side chain....	Electron Electron The electron is a subatomic particle that carries a negative electric charge. It has elementary particle and is believed to be a point particle.... s	Some bacteria Bacteria The Bacteria are a large group of unicellular microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals.... and most eukaryote Eukaryote Animals, plants, fungus, and protists are eukaryotes , organisms whose Cell are organized into complex structures enclosed within Cell membrane.... s \|- \| Coenzyme M Coenzyme M Coenzyme M is a coenzyme required for methyl-transfer reactions in the metabolism of methanogens. The coenzyme is an anion with the formula HSCH2CH2SO3-....	Methyl group Methyl group In chemistry, a methyl group is a hydrophobic alkyl functional group named after methane . It has the chemical formula -3 and is often abbreviated -Me....	Methanogen Methanogen Methanogens are archaea that produce methane as a metabolic byproduct in anoxic conditions. They are common in wetlands, where they are responsible for marsh gas, and in the guts of animals such as ruminants and humans, where they are responsible for the methane content of flatulence.... s \|- \|Coenzyme B Coenzyme B Coenzyme B is a coenzyme required for redox reactions in methanogens. The full chemical name of coenzyme B is 7-mercaptoheptanoylthreoninephosphate....	Electron Electron The electron is a subatomic particle that carries a negative electric charge. It has elementary particle and is believed to be a point particle.... s	Methanogen Methanogen Methanogens are archaea that produce methane as a metabolic byproduct in anoxic conditions. They are common in wetlands, where they are responsible for marsh gas, and in the guts of animals such as ruminants and humans, where they are responsible for the methane content of flatulence.... s \|- \|Methanofuran Methanofuran Methanofuran describes a family of chemical compounds found in methanogenic archaea. These species feature a 2-aminomethylfuran linked to phenoxy group....	Formyl group Aldehyde An aldehyde is an organic compound containing a terminal carbonyl group. This functional group, which consists of a carbon atom bonded to a hydrogen atom and double bond to an oxygen atom , is called the aldehyde group....	Methanogen Methanogen Methanogens are archaea that produce methane as a metabolic byproduct in anoxic conditions. They are common in wetlands, where they are responsible for marsh gas, and in the guts of animals such as ruminants and humans, where they are responsible for the methane content of flatulence.... s \|- \|Tetrahydromethanopterin Tetrahydromethanopterin Tetrahydromethanopterin, abbreviated H4MPT, is a coenzyme in methanogenesis. It is the carrier of the C1 group as it is reduced to the methyl level, before transferring to the coenzyme M....	Methyl group Methyl group In chemistry, a methyl group is a hydrophobic alkyl functional group named after methane . It has the chemical formula -3 and is often abbreviated -Me....	Methanogen Methanogen Methanogens are archaea that produce methane as a metabolic byproduct in anoxic conditions. They are common in wetlands, where they are responsible for marsh gas, and in the guts of animals such as ruminants and humans, where they are responsible for the methane content of flatulence.... s

Evolution

Coenzymes, such as ATP

Adenosine triphosphate

This article is about the chemical used by cells as an energy carrier. For other uses, see ATP .Adenosine-5'-triphosphate is a multifunctional nucleotide, and plays an important role in cell biology as a coenzyme that is the "molecule unit of currency" of intracellular energy transfer....
and NADH, are present in all known forms of life and form a core part of metabolism

Metabolism

Conservation (genetics)

Conservation may refer to:* Conservation genetics - "an interdisciplinary science that aims to apply genetic methods to the conservation and restoration of biodiversity."...
indicates that these molecules evolved very early in the development of living things. At least some of the current set of coenzymes may therefore have been present in the last universal ancestor

Last universal ancestor

The last universal ancestor is the most recent organism from which all organisms now living on Earth Common descent. Thus it is the most recent common ancestor of all current life on Earth....
, which lived about 4 billion years ago.

Coenzymes may have been present even earlier in the history of life

Timeline of evolution

This timeline of the evolution of life outlines the major events in the development of life on the planet Earth . For a thorough explanatory context, see the history of Earth, and geologic time scale....
on Earth. Interestingly, the nucleotide adenosine

Adenosine

Adenosine is a nucleoside composed of a molecule of adenine attached to a ribose sugar molecule moiety via a ?-N9-glycosidic bond....
is present in coenzymes that catalyse many basic metabolic reactions such as methyl, acyl, and phosphoryl group transfer, as well as redox

Redox

Redox describes all chemical reactions in which atoms have their oxidation number changed.This can be either a simple redox process such as the oxidation of carbon to yield carbon dioxide or the reduction of carbon by hydrogen to yield methane , or it can be a complex process such as the oxidation of sugar in the human body through a ser...
reactions. This ubiquitous chemical scaffold has therefore been proposed to be a remnant of the RNA world

RNA world hypothesis

The RNA world hypothesis proposes that a world filled with life based on ribonucleic acid predated current life based on deoxyribonucleic acid ....
, with early ribozyme

Ribozyme

A ribozyme is an RNA molecule that catalyzes a chemical reaction. Many natural ribozymes catalyze either the hydrolysis of one of their own phosphodiester bonds, or the hydrolysis of bonds in other RNAs, but they have also been found to catalyze the aminotransferase activity of the ribosome....
s evolving to bind a restricted set of nucleotides and related compounds. Adenosine-based coenzymes are thought to have acted as interchangeable adaptors that allowed enzymes and ribozymes to bind new coenzymes through small modifications in existing adenosine-binding domain

Protein domain

A protein domain is a part of protein sequence and tertiary structure that can biological evolution, function, and exist independently of the rest of the protein chain....
s, which had originally evolved to bind a different cofactor. This process of adapting a pre-evolved structure for a novel use is referred to as exaptation
Exaptation

Exaptation, cooption, and preadaptation are related terms referring to shifts in the function of a trait during evolution. For example, a trait can evolve because it served one particular function, but subsequently it may come to serve another....
.

History

The first coenzyme to be discovered was NAD⁺, which was identified by Arthur Harden

Arthur Harden

Arthur Harden was an England biochemist. He shared the Nobel Prize in Chemistry in 1929 with Hans Karl August Simon von Euler-Chelpin for their investigations into the fermentation of sugar and fermentative enzymes....
and William Youndin 1906. They noticed that adding boiled and filtered yeast

Yeast

Yeasts are eukaryote microorganisms classified in the Kingdom fungus, with about 1,500 species currently described; they dominate fungal diversity in the oceans....
extract greatly accelerated alcoholic fermentation in unboiled yeast extracts. They called the unidentified factor responsible for this effect a coferment. Through a long and difficult purification from yeast extracts, this heat-stable factor was identified as a nucleotide

Nucleotide

Hans von Euler-Chelpin

Hans Karl August Simon von Euler-Chelpin was a Germany-born Sweden biochemist. He won the Nobel Prize in Chemistry in 1929 with Arthur Harden for their investigations on the Fermentation of sugar and fermentative enzymes....
. Other coenzymes were identified throughout the early 20th century, with ATP being isolated in 1929 by Karl Lohmann, and coenzyme A being discovered in 1945 by Fritz Albert Lipmann

Fritz Albert Lipmann

Fritz Albert Lipmann was a German-American biochemist and a co-discoverer in 1945 of coenzyme A. For this, together with other research on coenzyme A, he was awarded half the Nobel Prize in Physiology or Medicine in 1953....
.

The functions of coenzymes were at first mysterious, but in 1936, Otto Heinrich Warburg

Otto Heinrich Warburg

Otto Heinrich Warburg , son of physicist Emil Warburg, was a Germany physiologist, medical doctor and Nobel laureate. Warburg was one of the twentieth century's leading Cell biology....
identified the function of NAD⁺ in hydride transfer. This discovery was followed in the early 1940s by the work of Herman Kalckar

Herman Kalckar

Herman Moritz Kalckar was a Danish biochemist who pioneered the study of cellular respiration. He trained as a medical doctor at the University of Copenhagen but later moved to America, becoming a professor of biology at Johns Hopkins University....
, who established the link between the oxidation of sugars and the generation of ATP. This confirmed the central role of ATP in energy transfer that had been proposed by Fritz Albert Lipmann in 1941. Later, in 1949, Morris Friedkin and Albert L. Lehninger

Albert L. Lehninger

Albert Lester Lehninger was an United States biochemist, and is widely regarded as a pioneer in the field of Biological thermodynamics. He made fundamental contributions to the current understanding of metabolism at a molecular level....
proved that the coenzyme NAD⁺ linked metabolic pathways such as the citric acid cycle and the synthesis of ATP.

External links

at City University of New York
City University of New York

Not to be confused with New York University formerly known as the University of the City of New York.For similar uses see University of New York...
at National Institutes of Health
National Institutes of Health

The National Institutes of Health is an agency of the United States Department of Health and Human Services and is the primary agency of the United States government responsible for biomedical and health-related research....

Coenzyme

Definition

Coenzymes as metabolic intermediates

Types

Vitamins and derivatives

Non-vitamins

Evolution

History

See also

Further reading

External links