Putrescine is an

organic compound Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-co ...

with the formula (CH₂)₄(NH₂)₂. It is a colorless solid that melts near room temperature. It is classified as a

diamine A diamine is an amine with two amino groups. Diamines are used as monomers to prepare polyamides, polyimides, and polyureas. The term ''diamine'' refers mostly to Primary (chemistry), primary diamines, as those are the most reactive. In terms of ...

. Together with

cadaverine Cadaverine is an organic compound with the formula (CH2)5(NH2)2. Classified as a diamine, it is a colorless liquid with an unpleasant odor. It is present in small quantities in living organisms but is often associated with the putrefaction of Tiss ...

, it is largely responsible for the foul odor of

putrefying Putrefaction is the fifth stage of death, following pallor mortis, livor mortis, algor mortis, and rigor mortis. This process references the breaking down of a body of an animal post-mortem. In broad terms, it can be viewed as the decomposit ...

flesh, but also contributes to other unpleasant odors.

Production

Putrescine is produced on an industrial scale by the

hydrogenation Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to redox, reduce or Saturated ...

succinonitrile Succinonitrile, also butanedinitrile, is a nitrile, with the formula of C2H4(CN)2. It is a colorless waxy solid which melts at 58 °C. Succinonitrile is produced by the addition of hydrogen cyanide to acrylonitrile (hydrocyanation): :CH2=CHCN ...

. Biotechnological production of putrescine from a renewable feedstock has been investigated. A metabolically engineered strain of ''

Escherichia coli ''Escherichia coli'' ( )Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. is a gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus '' Escherichia'' that is commonly fo ...

'' that produces putrescine at high concentrations in glucose mineral salts medium has been described.

Biochemistry

Spermidine synthase Spermidine synthase is an enzyme () that catalyzes the transfer of the propylamine group from ''S''-adenosylmethioninamine to putrescine in the biosynthesis of spermidine. The systematic name is S-adenosyl 3-(methylthio)propylamine:putrescine 3- ...

uses putrescine and ''S''-adenosylmethioninamine (decarboxylated ''S''-adenosyl methionine) to produce

spermidine Spermidine is a polyamine compound () found in ribosomes and living tissues and having various metabolic functions within organisms. Function Spermidine is an Aliphatic compound, aliphatic polyamine. Spermidine synthase (SPDS) catalyzes its form ...

. Spermidine in turn is combined with another ''S''-adenosylmethioninamine and gets converted to

spermine Spermine is a polyamine involved in cellular metabolism that is found in all eukaryotic cells. The precursor for synthesis of spermine is the amino acid ornithine. It is an essential growth factor in some bacteria as well. It is found as a p ...

. Putrescine is synthesized in small quantities by healthy living cells by the action of

ornithine decarboxylase The enzyme ornithine decarboxylase (, ODC) catalyzes the decarboxylation of ornithine (a product of the urea cycle) to form putrescine. This reaction is the committed step in polyamine synthesis. In humans, this protein has 461 amino acids ...

. Putrescine is synthesized biologically via two different pathways, both starting from

arginine Arginine is the amino acid with the formula (H2N)(HN)CN(H)(CH2)3CH(NH2)CO2H. The molecule features a guanidinium, guanidino group appended to a standard amino acid framework. At physiological pH, the carboxylic acid is deprotonated (−CO2−) a ...

. * In one pathway, arginine is converted into

agmatine Agmatine, also known as 4-aminobutyl-guanidine, was discovered in 1910 by Albrecht Kossel. It is a chemical substance which is naturally created from the amino acid arginine. Agmatine has been shown to exert modulatory action at multiple molecu ...

. The conversion is catalyzed by the enzyme arginine decarboxylase (ADC). Agmatine is transformed into N-carbamoylputrescine by agmatine imino hydroxylase (AIH). Finally, N-carbamoylputrescine is hydrolyzed to give putrescine. * In the second pathway, arginine is converted into

ornithine Ornithine is a non-proteinogenic α-amino acid that plays a role in the urea cycle. It is not incorporated into proteins during translation. Ornithine is abnormally accumulated in the body in ornithine transcarbamylase deficiency, a disorder of th ...

and then ornithine is converted into putrescine by

(ODC). Putrescine, via

metabolic intermediate Metabolic intermediates are compounds produced during the conversion of substrates (starting molecules) into final products in biochemical reactions within cells. Although these intermediates are of relatively minor direct importance to cell ...

s including ''N''-acetylputrescine,

γ-aminobutyraldehyde 4-Aminobutanal, also known as γ-aminobutyraldehyde, 4-aminobutyraldehyde, or GABA aldehyde, is a metabolite of putrescine and a biological precursor of γ-aminobutyric acid (GABA). It can be converted into GABA by the actions of diamine oxidas ...

(GABAL), ''N''-acetyl-γ-aminobutyric acid (''N''-acetyl-GABAL), and ''N''-acetyl-γ-aminobutyric acid (''N''-acetyl-GABA),

biotransformation Biotransformation is the biochemical modification of one chemical compound or a mixture of chemical compounds. Biotransformations can be conducted with whole cells, their lysates, or purified enzymes. Increasingly, biotransformations are effected ...

s mediated by

diamine oxidase Diamine oxidase (DAO), also known "amine oxidase, copper-containing, 1" (AOC1), formerly called histaminase, is an enzyme () involved in the metabolism, oxidation, and inactivation of histamine and other polyamines such as putrescine or spermid ...

(DAO),

monoamine oxidase B Monoamine oxidase B (MAO-B) is an enzyme that in humans is encoded by the ''MAOB'' gene. The protein encoded by this gene belongs to the flavin monoamine oxidase family. It is an enzyme located in the outer mitochondrial membrane. It catalyzes ...

(MAO-B),

aminobutyraldehyde dehydrogenase In enzymology, an aminobutyraldehyde dehydrogenase () is an enzyme that catalyzes the chemical reaction :4-aminobutanal + NAD+ + H2O \rightleftharpoons 4-aminobutanoate + NADH + 2 H+ The 3 substrates of this enzyme are 4-aminobutanal, NAD+, an ...

(ABALDH), and other

enzyme An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...

s, can act as a minor biological precursor of

γ-aminobutyric acid GABA (gamma-aminobutyric acid, γ-aminobutyric acid) is the chief inhibitory neurotransmitter in the developmentally mature mammalian central nervous system. Its principal role is reducing neuronal excitability throughout the nervous system. GA ...

(GABA) in the

brain The brain is an organ (biology), organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It consists of nervous tissue and is typically located in the head (cephalization), usually near organs for ...

and elsewhere. In 2021, it was discovered that MAO-B does not mediate

dopamine Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic chemical of the catecholamine and phenethylamine families. It is an amine synthesized ...

catabolism Catabolism () is the set of metabolic pathways that breaks down molecules into smaller units that are either oxidized to release energy or used in other anabolic reactions. Catabolism breaks down large molecules (such as polysaccharides, lipid ...

in the rodent

striatum The striatum (: striata) or corpus striatum is a cluster of interconnected nuclei that make up the largest structure of the subcortical basal ganglia. The striatum is a critical component of the motor and reward systems; receives glutamat ...

but instead participates in striatal GABA synthesis and that synthesized GABA in turn inhibits

dopaminergic Dopaminergic means "related to dopamine" (literally, "working on dopamine"), a common neurotransmitter. Dopaminergic substances or actions increase dopamine-related activity in the brain. Dopaminergic pathways, Dopaminergic brain pathways facil ...

neuron A neuron (American English), neurone (British English), or nerve cell, is an membrane potential#Cell excitability, excitable cell (biology), cell that fires electric signals called action potentials across a neural network (biology), neural net ...

s in this brain area. It has been found that MAO-B, via the putrescine pathway, importantly mediates GABA synthesis in

astrocyte Astrocytes (from Ancient Greek , , "star" and , , "cavity", "cell"), also known collectively as astroglia, are characteristic star-shaped glial cells in the brain and spinal cord. They perform many functions, including biochemical control of en ...

s in various brain areas, including in the

hippocampus The hippocampus (: hippocampi; via Latin from Ancient Greek, Greek , 'seahorse'), also hippocampus proper, is a major component of the brain of humans and many other vertebrates. In the human brain the hippocampus, the dentate gyrus, and the ...

cerebellum The cerebellum (: cerebella or cerebellums; Latin for 'little brain') is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as it or eve ...

, striatum,

cerebral cortex The cerebral cortex, also known as the cerebral mantle, is the outer layer of neural tissue of the cerebrum of the brain in humans and other mammals. It is the largest site of Neuron, neural integration in the central nervous system, and plays ...

, and

substantia nigra pars compacta The pars compacta (SNpc, SNc) is one of two subdivisions of the ''substantia nigra'' of the midbrain (the other being the pars reticulata); it is situated medial to the ''pars reticulata''. It is formed by dopaminergic neurons. It projects to t ...

(SNpc).

Occurrence

Putrescine is found in all

organism An organism is any life, living thing that functions as an individual. Such a definition raises more problems than it solves, not least because the concept of an individual is also difficult. Many criteria, few of them widely accepted, have be ...

s. Putrescine is widely found in plant tissues, often being the most common polyamine present within the organism. Its role in development is well documented, but recent studies have suggested that putrescine also plays a role in stress responses in plants, both to biotic and abiotic stressors. The absence of putrescine in plants is associated with an increase in both parasite and fungal population in plants. Putrescine serves an important role in a multitude of ways, which include: a

cation An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convent ...

substitute, an

osmolyte Osmolytes are low-molecular-weight organic compounds that influence the properties of biological fluids. Osmolytes are a class of organic molecules that play a significant role in regulating osmotic pressure and maintaining cellular homeostasis in ...

, or a transport protein. It also serves as an important regulator in a variety of surface proteins, both on the cell surface and on organelles, such as the mitochondria and chloroplasts. A recorded increase of ATP production has been found in mitochondria and ATP synthesis by chloroplasts with an increase in mitochondrial and chloroplastic putrescine, but putrescine has also been shown to function as a developmental inhibitor in some plants, which can be seen as

dwarfism Dwarfism is a condition of people and animals marked by unusually small size or short stature. In humans, it is sometimes defined as an adult height of less than , regardless of sex; the average adult height among people with dwarfism is . '' ...

and late flowering in ''Arabiadopsis'' plants. Putrescine production in plants can also be promoted by fungi in the soil.

Piriformospora indica ''Serendipita indica'' (synonym ''Piriformospora indica'') is a fungal species of the order Sebacinales. It is an endophytic root-colonising species, discovered from orchid plants in the Thar desert in Rajasthan, India by Prof. Ajit Verma and gro ...

(''P. indica'') is one such fungus, found to promote putrescine production in ''

Arabidopsis ''Arabidopsis'' (rockcress) is a genus in the family Brassicaceae. They are small flowering plants related to cabbage and mustard. This genus is of great interest since it contains thale cress (''Arabidopsis thaliana''), one of the model organ ...

'' and common garden tomato plants. In a 2022 study it was shown that the presence of this fungus had a promotional effect on the growth of the root structure of plants. After

gas chromatography Gas chromatography (GC) is a common type of chromatography used in analytical chemistry for Separation process, separating and analyzing compounds that can be vaporized without Chemical decomposition, decomposition. Typical uses of GC include t ...

testing, putrescine was found in higher amounts in these root structures. Plants that had been inoculated with ''P. indica'' had presented an excess of arginine decarboxylase. This is used in the process of making putrescine in plant cells. One of the downstream effects of putrescine in root cells is the production of

auxin Auxins (plural of auxin ) are a class of plant hormones (or plant-growth regulators) with some morphogen-like characteristics. Auxins play a cardinal role in coordination of many growth and behavioral processes in plant life cycles and are essent ...

. That same study found that putrescine added as a fertilizer showed the same results as if it was inoculated with the fungus, which was also shown in ''Arabidopsis'' and

barley Barley (), a member of the grass family, is a major cereal grain grown in temperate climates globally. It was one of the first cultivated grains; it was domesticated in the Fertile Crescent around 9000 BC, giving it nonshattering spikele ...

. The evolutionary foundations of this connection and putrescine are still unclear. Putrescine is a component of

bad breath Bad breath, also known as halitosis, is a symptom in which a noticeably unpleasant breath odour is present. It can result in anxiety among those affected. It is also associated with depression and symptoms of obsessive compulsive disorder. Th ...

and

bacterial vaginosis Bacterial vaginosis (BV) is an infection of the vagina caused by excessive growth of bacteria. Common symptoms include increased vaginal discharge that often smells like fish. The discharge is usually white or gray in color. Burning with urina ...

. It is also found in

semen Semen, also known as seminal fluid, is a bodily fluid that contains spermatozoon, spermatozoa which is secreted by the male gonads (sexual glands) and other sexual organs of male or hermaphrodite, hermaphroditic animals. In humans and placen ...

and some microalgae, together with

and

Uses

Putrescine reacts with

adipic acid Adipic acid or hexanedioic acid is the organic compound with the formula C6H10O4. It a white crystalline powder at standard temperature and pressure. From an industrial perspective, it is the most important dicarboxylic acid at about 2.5 billion ...

to yield the

polyamide A polyamide is a polymer with repeating units linked by amide bonds. Polyamides occur both naturally and artificially. Examples of naturally occurring polyamides are proteins, such as wool and silk. Artificially made polyamides can be made throug ...

nylon 46 Nylon 46 (nylon 4-6, nylon 4/6 or nylon 4,6, PA46, Polyamide 46) is a high heat resistant polyamide or nylon. Envalior (formerly DSM) is the only commercial supplier of this resin, which markets under the trade name Stanyl. Nylon 46 is an alipha ...

, which is marketed by Envalior (formerly DSM) under the trade name Stanyl. Application of putrescine, along with other polyamines, can be used to extend the shelf life of fruits by delaying the ripening process. Pre-harvest application of putrescine has been shown to increase plant resistance to high temperatures and drought. Both of these effects seem to result from lowered ethylene production following exogenous putrescine exposure. Due to its role in putrification, putrescine has also been proposed as a biochemical marker for determining how long a corpse has been decomposing. Putrescine together with

chitosan Chitosan is a linear polysaccharide composed of randomly distributed β-(1→4)-linked D-glucosamine (deacetylated unit) and ''N''-acetyl-D-glucosamine (acetylated unit). It is made by treating the chitin shells of shrimp and other crusta ...

has been successfully used in

postharvest In agriculture, postharvest handling is the stage of crop production immediately following harvest, including cooling, cleaning, sorting and packing. The instant a crop is removed from the ground, or separated from its parent plant, it begins t ...

physiology as a natural fruit coating. Putrescine with chitosan treated fruits had higher antioxidant capacity and

activities than untreated fruits. Fresh

strawberries The garden strawberry (or simply strawberry; ''Fragaria × ananassa'') is a widely grown hybrid plant cultivated worldwide for its fruit. The genus ''Fragaria'', the strawberries, is in the rose family, Rosaceae. The fruit is appreciated f ...

coated have lower

decay Decay may refer to: Science and technology * Bit decay, in computing * Decay time (fall time), in electronics * Distance decay, in geography * Software decay, in computing Biology * Decomposition of organic matter * Mitochondrial decay, in g ...

percentage, higher tissue firmness, contents of total soluble solids. Nanoparticles of putrescine with chitosan are effective in preserving the nutritional quality and prolonging the post-harvest life of strawberries during storage up to 12 days.

History

Putrescine and

were first described in 1885 by the

Berlin Berlin ( ; ) is the Capital of Germany, capital and largest city of Germany, by both area and List of cities in Germany by population, population. With 3.7 million inhabitants, it has the List of cities in the European Union by population withi ...

physician Ludwig Brieger (1849–1919).

Toxicity

In rats, putrescine has a low acute oral toxicity of 2000 mg/kg body weight, with no-observed-adverse-effect level of 2000 ppm (180 mg/kg body weight/day).

References

External links

Putrescine MS Spectrum
{{Authority control Diamines Foul-smelling chemicals NMDA receptor antagonists 1,4-Butanediyl compounds Substances discovered in the 19th century