The short version of Tetrapeptide fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2025-12-31 and is reviewed periodically as new material appears.
The compound is described in the literature as a derivative of epithalamin, a preparation obtained from bovine pineal tissue. Work on this peptide family was carried out mainly by a research group in Saint Petersburg beginning in the 1980s, and the substance was later registered for clinical use in Russia under the name Epitalon. Outside that region it is generally treated as a research chemical rather than an approved medicine. Statements about its biological activity rest on a relatively small number of studies, and independent replication remains limited.
In its supplied form epitalon is a white to off-white powder, usually lyophilized and often hygroscopic. It dissolves readily in water and in aqueous buffers, and it is commonly handled as the acetate or trifluoroacetate salt to improve stability during purification and drying. The amide backbone is labile in aqueous media, so solutions are less durable than the dry solid. Handling notes in the chemical literature therefore emphasize keeping the powder dry, cool and shielded from light until it is dissolved.
Storage recommendations center on limiting moisture, heat, and light. The dry powder is generally kept at minus 20 degrees Celsius, and some suppliers recommend minus 80 degrees for long-term archival. Once dissolved, solutions are usually aliquoted and frozen to avoid repeated freeze-thaw cycles, which can promote aggregation or degradation. Aqueous stability depends on pH and concentration, and buffered saline is often preferred over plain water for biological work. Stability data specific to epitalon remain limited, so general peptide-handling practices are applied by analogy rather than from product-specific validation.
Epitalon is a synthetic tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, abbreviated AEDG. Its molecular formula is C14H22N4O9 and its calculated monoisotopic mass is approximately 390.35 daltons. The compound does not occur naturally as a free peptide; it is produced by solid-phase peptide synthesis. Because it contains two acidic residues and no basic residues, the neutral form carries a net negative charge at physiological pH. This charge profile influences how the peptide behaves in solution and during chromatographic analysis.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic tetrapeptide | Four residues, linear chain |
| Residue sequence | Ala-Glu-Asp-Gly | Single-letter form AEDG |
| Calculated mass | 390.3 daltons | Value for the free, uncharged form |
| Appearance | White to off-white powder | Usually supplied lyophilized |
| Solubility | Freely soluble in water | Often handled as a salt form |
The compound is generally presented as a synthetic fragment of epithalamin, a pineal gland extract investigated in the former Soviet Union from the 1970s onward. Vladimir Khavinson and colleagues in Saint Petersburg developed short peptides modelled on such extracts, and epitalon became the most widely cited of those sequences. Most primary reports appeared in Russian-language journals or in proceedings with limited international circulation. Independent replication in laboratories outside that network remains sparse, and much repeated secondary material traces back to a small number of originating groups.
Laboratory work has examined effects on telomerase activity in cultured cells, on melatonin rhythms in animals, and on markers of oxidative stress. Some experiments report measurable changes while others show none, and the reported findings rest largely on small studies. The absence of large independent trials means the generality of these results is unresolved rather than settled. Review articles occasionally apply the label geroprotector, a term that reflects a research hypothesis about ageing rather than an established clinical finding.
Material supplied for laboratory use is normally a lyophilised white to off-white powder that dissolves readily in water and in isotonic saline. Lyophilised cakes are hygroscopic and should be equilibrated to room temperature before opening to limit condensation on the solid. Solutions are typically prepared at milligram-per-millilitre concentrations and divided into single-use aliquots, because repeated freeze–thaw cycles degrade short peptides. Aqueous solutions are far less stable than the dry powder, and identity is usually verified by mass spectrometry alongside purity estimation from reversed-phase high-performance liquid chromatography.
Epitalon is a synthetic linear tetrapeptide with the sequence alanine–glutamate–aspartate–glycine, abbreviated AEDG. Its molecular formula is C14H22N4O9 and the calculated mass is approximately 390.35 g/mol. The compound is made by solid-phase peptide synthesis rather than extracted from tissue, although early work described it as a short fragment of a peptide fraction obtained from bovine pineal extract. In the research literature the spelling epitalon and the variant epithalone both appear, while AEDG is the standard code used in peptide nomenclature.
（TG:@pojiaai）Epitalon is a synthetic linear tetrapeptide with the sequence alanine-glutamate-aspartate-glycine, abbreviated AEDG. It emerged from work on epithalamin, a peptide fraction prepared from bovine pineal tissue, and was designed as a short, chemically defined analogue of that extract. Early publications came mainly from Russian laboratories studying pineal peptides and aging-related endpoints. The compound appears in the literature under several spellings, including epithalon and epithalone, which complicates systematic searching. Its small size makes solid-phase assembly and routine analytical characterization straightforward.
Chemically, the molecule consists of four amino acid residues joined by three peptide bonds, with a free N-terminal amino group and a free C-terminal carboxyl group. Its molecular formula is C14H22N4O9, and its monoisotopic mass is approximately 390 daltons. The acidic glutamate and aspartate side chains give the peptide a net negative charge near neutral pH, a property that shapes its chromatographic behaviour and solubility profile. No disulfide bridges or other post-translational modifications are present, so the primary sequence alone defines the structure.
1908: George W. McCoy's discovery that rodents were a reservoir of bubonic plague. 1911: George W. McCoy, Charles W. Chapin, William B. Wherry, and B. H. Lamb described the previously unknown tularemia. 1924: Roscoe R. Spencer and Ralph R. Parker developed a vaccine against Rocky Mountain spotted fever. 1930: Sanford M. Rosenthal developed a treatment for mercury poisoning used widely before the development of dimercaptoethanol. 1943: Wilton R. Earle pioneered the cell culture process and published a paper describing the production of malignancy in vitro, Katherine K. Sanford developed the first clone from an isolated cancer cell, and Virginia J. Evans devised a medium that supported growth of cells in vitro. 1940s–1950s: Bernard Horecker and colleagues described the pentose phosphate pathway. 1950s: Julius Axelrod discovered a new class of enzymes, cytochrome P450 monooxygenases, a fundamental of drug metabolism. 1950: Earl Stadtman discovered phosphotransacetylose, elucidating the role of acetyl CoA in fatty acid metabolism. 1960s: Discovered the first human slow virus disease, kuru, which is a degenerative, fatal infection of the central nervous system. This discovery of a new mechanism for infectious diseases revolutionized thinking in microbiology and neurology. 1960s: Defined the mechanisms that regulate noradrenaline, one of the most important neurotransmitters in the brain. 1960s: Developed the first licensed rubella vaccine and the first test for rubella antibodies for large scale testing.
== History == B&O Supprettes (the name is derived from the generic term 'belladonna/opium suppository') is an "unapproved" drug according to the Food and Drug Administration (FDA) – that is, the drug existed before the Food, Drug and Cosmetic Act of 1938. Accordingly, the compound has never undergone specific medical trials, and its efficacy has never been required to be demonstrated. The FDA has put pressure on the manufacturers of this drug for this reason. The original manufacturer of the Supprettes, Eli Lilly and Company, has long since lost any patent to the drug. Amerifit, which manufactured generic Supprettes prior to 2008, was cautioned by the FDA due to the unapproved nature of the drug combination. Since 2008, Paddock Laboratories has manufactured a generic version of the Supprettes after working with the FDA on marketing issues related to the unapproved nature of the drug.
Curare is an alkaloid poison extracted from native South American plants in the Chondrondendron genus. They were initially used by indigenous groups as a paralyzing agent for hunting. European scientists later discovered that tubocurarine was the major constituent responsible for the paralyzing effect by acting on the neuromuscular junction. Anasthesiologists Harold Griffith and Enid Johnson first documented the successful use of curare, in a clinical trial to facilitate muscle relaxation in a healthy patient undergoing appendicectomy in 1942. Before the use of curare, anesthesiologist required large doses of anesthetic such as chloroform to achieve similar paralyzing effects, hence increased the risk of life-threatening effects in elderly patients who had cardiac complications. Ever since, neuromuscular agents have been commonly used in practice during anesthetic procedures. The clinical trial conducted by Griffith and Johnson also paved the way for discovery of many more neuromuscular drugs for surgical use.
March 26 COVID-19 pandemic Maine reports its first case of the Lineage P.1 variant, which was originally detected in Brazil. Wisconsin confirms their first cases of the Lineage P.1 and 501.V2 variants of SARS-CoV-2. Arizona reports its first case of the 501.V2 variant, which was originally detected in South Africa. New Jersey amends its alcohol and cannabis laws to allow police to notify parents or guardians after a first-time offense by a minor, following strong opposition to the prohibition on first-time notifications implemented when New Jersey legalized cannabis the previous month. The U.S. Food and Drug Administration (FDA) approves Abecma to treat multiple myeloma. Abecma is the first cell-based gene therapy approved by the FDA for the treatment of multiple myeloma. March 29 In Minnesota, opening statements begin at the trial of former police officer Derek Chauvin, who is accused of murdering 46-year-old black man George Floyd by kneeling on his neck. The Arkansas Senate passed, HB1570, a bill that prohibited normally functioning and physically healthy minors from puberty blockers, cross-sex hormones, and genital and non-genital invasive surgical alterations. A judge orders three men charged with plotting to kidnap Michigan Governor Gretchen Whitmer to stand trial, after a three-day preliminary hearing. Threat of terrorism charges are also dismissed against two of the defendants. Killing of Adam Toledo – A 13-year-old Latino boy, Adam Toledo, is shot and killed by an officer of the Chicago Police Department.
== Autoproteolytic activity == The use of high-resolution ion-mobility mass spectrometry (IMS-MS) on HPLC-purified alpha-synuclein in vitro has shown alpha-synuclein to be autoproteolytic (self-proteolytic), generating a variety of small molecular weight fragments upon incubation. The 14.46 kDa protein was found to generate numerous smaller fragments, including 12.16 kDa (amino acids 14–133) and 10.44 kDa (40–140) fragments formed through C- and N-terminal truncation and a 7.27 kDa C-terminal fragment (72–140). The 7.27 kDa fragment, which contains the majority of the NAC region, aggregated considerably faster than full-length alpha-synuclein. It is possible that these autoproteolytic products play a role as intermediates or cofactors in the aggregation of alpha-synuclein in vivo.
Sources: en.wikipedia.org
They rendezvous with local Interpol agent Gail Runciter and proceed to the safehouse, where an elderly Zola, in a wheelchair and requiring an oxygen mask, seemingly overpowers Kate Neville's telepathy with his evil visions of destruction. Runciter lures Fury away from the group and shocks him with a device before revealing herself to be Viper in disguise. She then kisses Fury with poisoned lipstick, leaving him unconscious, enabling Hydra to retake Zola. Fury learns he has 48 hours to live unless he can recover a sample of Viper's DNA from which to develop an antidote. Hydra threatens to attack Manhattan with the virus, barring payment of US $1 billion, and as proof of their threat, the real Gail Runciter is found, dying from the virus. After Fury and his team brief the President of the United States, Pierce determines from a chip from a laptop sold in the Aleutian Islands that the Hydra base might be there. Fury has his people split into two teams, one led by de Fontaine heading to Manhattan to find the refrigerated truck they believe will be needed to deploy the virus, and the other with Fury leading Pierce and Neville to the Aleutian Islands. Upon arriving in the Aleutian Islands and confirming that a Hydra transmission has come from there, Fury's plane is shot down by heat-seeking missiles. In Manhattan, de Fontaine's team figures out that the refrigerator truck is disguised as a garbage truck, while Fury and his team, having bailed out of the airplane in time, infiltrate the Hydra base.
=== Sheep === Cysteine is required by sheep to produce wool. It is an essential amino acid that is taken in from their feed. As a consequence, during drought conditions, sheep produce less wool; however, transgenic sheep that can make their own cysteine have been developed.
=== Ecuador intervention === On March 6, 2026, the Operation was expanded militarily in Ecuador when the United States participated in bombing Comandos de la Frontera, during the Ecuadorian conflict (2024–present).
=== Reagents === The diketopiperazine obtains from glycylserine is a reagent for the preparation of C-alkylated derivatives of glycine. This approach is useful for the production of unnatural amino acids with stereochemical control. The diketopiperazine skeleton protects both the N and O termini of the glycine. For this application, the diketopiperazine is O-alkylated with concomitant N-deprotonation to give what is called the Schöllkopf reagent.
Sources: en.wikipedia.org
=== Anxiety disorders === Panic disorder with or without agoraphobia. Clonazepam has also been found effective in treating other anxiety disorders, such as social phobia, but this is an off-label use. The effectiveness of clonazepam in the short-term treatment of panic disorder has been demonstrated in controlled clinical trials. Some long-term trials have suggested a benefit of clonazepam for up to three years without the development of tolerance.
== Bibliography == Greensmith, M. (1998). Practical Dehydration. Woodhead Publishing, Ltd. Genskow, L.R.; Beimesch, W.E.; Hecht, J.P.; Kemp, I.C.; Langrish, T.; Schwartzbach, C.; Smith, (F).L. (2007). Chemical Engineers' Handbook. Mc Graw Hill Professional. pp. Chapter 12 (Evaporative Cooling and Solids Drying). A.S., Mujumdar (1998). Handbook of Industrial Drying. Boca Ratón: CRC Press.
== Education platforms == While bioinformatics is taught as an in-person master's degree at many universities, there are many other methods and technologies available to learn and obtain certification in the subject. The computational nature of bioinformatics lends it to computer-aided and online learning. Software platforms designed to teach bioinformatics concepts and methods include Rosalind and online courses offered through the Swiss Institute of Bioinformatics Training Portal. The Canadian Bioinformatics Workshops provides videos and slides from training workshops on their website under a Creative Commons license. The 4273π project or 4273pi project also offers open source educational materials for free. The course runs on low cost Raspberry Pi computers and has been used to teach adults and school pupils. 4273 is actively developed by a consortium of academics and research staff who have run research level bioinformatics using Raspberry Pi computers and the 4273π operating system. MOOC platforms also provide online certifications in bioinformatics and related disciplines, including Coursera's Bioinformatics Specialization at the University of California, San Diego, Genomic Data Science Specialization at Johns Hopkins University, and EdX's Data Analysis for Life Sciences XSeries at Harvard University.
== Particle physics == Quarks and gluons have color charge, which is always conserved like electric charge, and there is a continuity equation for such color charge currents (explicit expressions for currents are given at gluon field strength tensor). There are many other quantities in particle physics which are often or always conserved: baryon number (proportional to the number of quarks minus the number of antiquarks), electron number, mu number, tau number, isospin, and others. Each of these has a corresponding continuity equation, possibly including source / sink terms.
Throughout the year, and leading into the vote count, Heppell was widely considered to be the favourite for the Ron Evans Medal, awarded to the rising star of each season. He won the medal, polling 44 of a possible 45 votes and became the first Essendon player to win the award. Heppell described winning the award as "a dream come true". He continued his ascent as an emerging star by finishing third in the clubs best and fairest award count, Essendon's best and fairest award; his second consecutive top-three placing. Having played his first two seasons largely off half-back, Heppell moved into a ball-winning role in the midfield in 2013, averaging 24 disposals for the season. He polled three Brownlow Medal votes for his 36-possession and two-goal effort against Melbourne in round 2 and was in the best players for the comeback win over Carlton in round 11. Heppell continued his upward climb throughout the 2014 season, winning his maiden Crichton Medal, receiving his first selection in the All-Australian team, and polled 14 votes in the 2014 Brownlow Medal.
Sources: en.wikipedia.org
The peptide contains four residues in the order alanine, glutamate, aspartate and glycine, abbreviated AEDG. The chain is linear and held together by three peptide bonds. Its calculated mass for the uncharged free form is about 390.3 daltons.
Epithalamin refers to a crude preparation derived from bovine pineal tissue, which contains many components. Epitalon is a single synthetic tetrapeptide identified from that material and produced by chemical synthesis. The two names are sometimes confused because early reports treated the synthetic peptide as an active fragment of the extract.
It has been registered for clinical use in Russia, where it is associated with a small family of short peptides. In most other jurisdictions it is not an approved medicine and is traded as a research chemical. Regulatory status varies by country and changes over time.
Epitalon is a synthetic tetrapeptide built from four amino acids: alanine, glutamate, aspartate, and glycine. It is not extracted from a natural source but made in the laboratory by chemical synthesis. Its short length makes it relatively straightforward to produce at high purity.