Serotonin or 5-hydroxytryptamine (5-HT) is a monoamine neurotransmitter. Its biological function is complex and multifaceted, modulating mood, cognition, reward, learning, memory, and numerous physiological processes such as vomiting and vasoconstriction.
Tryptophan is an α-amino acid that is used in the biosynthesis of proteins. Tryptophan contains an α-amino group, an α-carboxylic acid group, and a side chain indole, making it a non-polar aromatic amino acid. It is essential in humans, meaning that the body cannot synthesize it and it must be obtained from the diet. Tryptophan is also a precursor to the neurotransmitter serotonin, the hormone melatonin, and vitamin B3. It is encoded by the codon UGG.
Monoamine neurotransmitters are neurotransmitters and neuromodulators that contain one amino group connected to an aromatic ring by a two-carbon chain (such as -CH2-CH2-). Examples are dopamine, norepinephrine and serotonin.
Tryptophan synthase or tryptophan synthetase is an enzyme that catalyses the final two steps in the biosynthesis of tryptophan. It is commonly found in Eubacteria, Archaebacteria, Protista, Fungi, and Plantae. However, it is absent from Animalia. It is typically found as an α2β2 tetramer. The α subunits catalyze the reversible formation of indole and glyceraldehyde-3-phosphate (G3P) from indole-3-glycerol phosphate (IGP). The β subunits catalyze the irreversible condensation of indole and serine to form tryptophan in a pyridoxal phosphate (PLP) dependent reaction. Each α active site is connected to a β active site by a 25 angstrom long hydrophobic channel contained within the enzyme. This facilitates the diffusion of indole formed at α active sites directly to β active sites in a process known as substrate channeling. The active sites of tryptophan synthase are allosterically coupled.
Tryptamine is a monoamine alkaloid. It contains an indole ring structure, and is structurally similar to the amino acid tryptophan, from which the name derives. Tryptamine is found in trace amounts in the brains of mammals and is hypothesized to play a role as a neuromodulator or neurotransmitter. Similar to other trace amines, tryptamine binds to human trace amine-associated receptor 1 (TAAR1) as an agonist.
A biogenic amine is a biogenic substance with one or more amine groups. They are basic nitrogenous compounds formed mainly by decarboxylation of amino acids or by amination and transamination of aldehydes and ketones. Biogenic amines are organic bases with low molecular weight and are synthesized by microbial, vegetable and animal metabolisms. In food and beverages they are formed by the enzymes of raw material or are generated by microbial decarboxylation of amino acids.
Aromatic L-amino acid decarboxylase, also known as DOPA decarboxylase (DDC), tryptophan decarboxylase, and 5-hydroxytryptophan decarboxylase, is a lyase enzyme.
Shikimic acid, more commonly known as its anionic form shikimate, is a cyclohexene, a cyclitol and a cyclohexanecarboxylic acid. It is an important biochemical metabolite in plants and microorganisms. Its name comes from the Japanese flower shikimi, from which it was first isolated in 1885 by Johan Fredrik Eykman. The elucidation of its structure was made nearly 50 years later.
Chorismic acid, more commonly known as its anionic form chorismate, is an important biochemical intermediate in plants and microorganisms. It is a precursor for:
Indole alkaloids are a class of alkaloids containing a structural moiety of indole; many indole alkaloids also include isoprene groups and are thus called terpene indole or secologanin tryptamine alkaloids. Containing more than 4100 known different compounds, it is one of the largest classes of alkaloids. Many of them possess significant physiological activity and some of them are used in medicine. The amino acid tryptophan is the biochemical precursor of indole alkaloids.
Tryptophan hydroxylase (TPH) is an enzyme (EC 1.14.16.4) involved in the synthesis of the neurotransmitter serotonin. Tyrosine hydroxylase, phenylalanine hydroxylase, and tryptophan hydroxylase together constitute the family of biopterin-dependent aromatic amino acid hydroxylases. TPH catalyzes the following chemical reaction
Aralkylamine N-acetyltransferase (AANAT), also known as arylalkylamine N-acetyltransferase or serotonin N-acetyltransferase (SNAT), is an enzyme that is involved in the day/night rhythmic production of melatonin, by modification of serotonin. It is in humans encoded by the ~2.5 kb AANAT gene containing four exons, located on chromosome 17q25. The gene is translated into a 23 kDa large enzyme. It is well conserved through evolution and the human form of the protein is 80% identical to sheep and rat AANAT. It is an acetyl-CoA-dependent enzyme of the GCN5-related family of N-acetyltransferases (GNATs). It may contribute to multifactorial genetic diseases such as altered behavior in sleep/wake cycle and research is on-going with the aim of developing drugs that regulate AANAT function.
An aromatic amino acid (AAA) is an amino acid that includes an aromatic ring. Among the 20 standard amino acids, the following are aromatic: phenylalanine, tryptophan and tyrosine. However, in addition to being aromatic, tyrosine can be classified as a polar amino acid. In addition, while histidine contains an aromatic ring, its basic properties cause it to be predominantly classified as a polar amino acid; however, the compound is still aromatic.
Camptothecin (CPT) is a topoisomerase poison. It was discovered in 1966 by M. E. Wall and M. C. Wani in systematic screening of natural products for anticancer drugs. It was isolated from the bark and stem of Camptotheca acuminata, a tree native to China used as a cancer treatment in Traditional Chinese Medicine. It has been used clinically more recently in China for the treatment of gastrointestinal tumors.CPT showed remarkable anticancer activity in preliminary clinical trials especially against breast, ovarian, colon, lung, and stomach cancers However, it has low solubility and adverse effects have been reported when used therapeutically, so synthetic and medicinal chemists have developed numerous syntheses of camptothecin and various derivatives to increase the benefits of the chemical, with good results. Four CPT analogues have been approved and are used in cancer chemotherapy today, topotecan, irinotecan, belotecan, and trastuzumab deruxtecan. Camptothecin has also been found in other plants including Chonemorpha fragrans. In addition to being a anti-tumor agent, Camptothecin has also shown anti-HIV activity because it interrupts self-association of the viral-infectivity factor found in many retroviruses including HIV
In enzymology, an indole 2,3-dioxygenase (EC 1.13.11.17) is an enzyme that catalyzes the chemical reaction
In enzymology, a phosphoribosylanthranilate isomerase [ PRAI ] is an enzyme that catalyzes the third step of the synthesis of the amino acid tryptophan.
Tryptophan hydroxylase 1 (TPH1) is an isoenzyme of tryptophan hydroxylase which in humans is encoded by the TPH1 gene.
Hypertryptophanemia, is a rare autosomal recessive metabolic disorder that results in a massive buildup of the amino acid tryptophan in the blood, with associated symptoms and tryptophanuria.
Indole is an aromatic heterocyclic organic compound with formula C8H7N. It has a bicyclic structure, consisting of a six-membered benzene ring fused to a five-membered pyrrole ring. Indole is widely distributed in the natural environment and can be produced by a variety of bacteria. As an intercellular signal molecule, indole regulates various aspects of bacterial physiology, including spore formation, plasmid stability, resistance to drugs, biofilm formation, and virulence. The amino acid tryptophan is an indole derivative and the precursor of the neurotransmitter serotonin.
Substituted tryptamines, or serotonin analogues, are organic compounds which may be thought of as being derived from tryptamine itself. The molecular structures of all tryptamines contain an indole ring, joined to an amino (NH2) group via an ethyl (−CH2–CH2−) sidechain. In substituted tryptamines, the indole ring, sidechain, and/or amino group are modified by substituting another group for one of the hydrogen (H) atoms.
