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 2025-08-14 and is reviewed periodically as new material appears.
Several names circulate for the same molecule, including epitalon, epithalone, epithalamin tetrapeptide, and the sequence code AEDG. A CAS registry number, 307297-39-8, is commonly cited for it, though catalogue entries should be checked against supplier documentation because mislabelled records occur. In its usual form the peptide carries free amino and carboxyl termini and is neither glycosylated nor lipidated. Researchers distinguish the defined tetrapeptide from epithalamin itself, a crude pineal preparation containing many peptides that is not chemically characterised.
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.
Residue composition is the property that most cleanly separates verified material from mislabelled samples. Alanine, glutamate, aspartate and glycine appear in that order from the N-terminus, and the two acidic residues sit in the middle of the chain. Because the peptide is short, it can be produced by solid-phase synthesis and characterised by mass spectrometry without ambiguity. Any reported sample whose measured mass departs substantially from 390 daltons is a different compound or a degraded mixture rather than epitalon.
Epitalon is a synthetic tetrapeptide whose four residues are alanine, glutamate, aspartate and glycine, commonly abbreviated AEDG. Its molecular formula is C14H22N4O9 and its monoisotopic mass is near 390.35 daltons. The peptide carries two acidic side chains, so it is neutral to negatively charged in most aqueous buffers. Published reference summaries usually list it under both spellings, epitalon and epithalon, and treat the two names as the same material.
| Property | Value | Notes |
|---|---|---|
| Amino acid sequence | Ala-Glu-Asp-Gly | Linear tetrapeptide, also written AEDG |
| Molecular mass | About 390.35 g/mol | Value calculated from the sequence |
| Appearance | White to off-white powder | Lyophilised material forms a loose cake |
| Solubility | Freely soluble in water | Also dissolves in isotonic saline |
| Storage | -20 °C, desiccated | Aliquot solutions to avoid freeze–thaw cycling |
== See also == Crystallography DSSP (hydrogen bond estimation algorithm) Nuclear magnetic resonance Protein Structure Evaluation Suite & Server (PROSESS) Protein structure prediction Resolution by Proxy (ResProx) Root-mean-square deviation Structural bioinformatics Structure validation
== Awards and honors == Wilhelm Exner Medal, 1958 Johann Josef Ritter von Precht Medal of TU wien, 1965 Erwin Schrödinger Prize of the Austrian Academy of Sciences, 1970 M.S. Tswett Chromatography Award, 1974 (first year awarded) Commemorative M.S. Tswett Medal of the U.S.S.R. Academy of Sciences, 1978 Honorary degree from the Technische Universität Berlin First-class cross of the Austrian Order for Science and Art A Street in Munich was called after her (Erika-Cremer-Straße in 81829 München)
==== Hungary ==== In 1994, 265 mummified bodies were found in the crypt of a Dominican church in Vác, Hungary from the 1729–1838 period. The discovery proved to be scientifically important, and by 2006 an exhibition was established in the Museum of Natural History in Budapest. Unique to the Hungarian mummies are their elaborately decorated coffins, with no two being exactly alike.
Adequate sleep duration and quality have been linked to lower cardiometabolic risk, with insufficient sleep associated with higher rates of hypertension, obesity, and dysregulated glucose metabolism. Reducing alcohol intake may also be protective, as heavy use can worsen hepatic and metabolic outcomes in people with underlying metabolic risk. Although individual-level changes are effective for many people, adherence varies widely in real-world settings. Public-health bodies—including the International Obesity Taskforce—argue that sustained prevention requires population-level interventions, such as improved access to healthy foods, urban design that supports physical activity, and policies addressing socioeconomic drivers of obesity.
The mould needs air to grow, so cultivation required a container with a large surface area. Initially, glass bottles laid on their sides were used. Most laboratory containers did not provide a large, flat area, and so were an uneconomical use of incubator space. The bedpan was found to be practical, and was the basis for specially-made ceramic containers fabricated by J. Macintyre and Company in Burslem. These containers were rectangular in shape and could be stacked to save space. The MRC agreed to Florey's request for £300 (equivalent to £15,000 in 2025) and £2 each per week (equivalent to £97 in 2025) for two women factory hands. In 1943 Florey asked for their wages to be increased to £2 10s each per week (equivalent to £99 in 2025). Heatley collected the first 174 of an order for 500 vessels on 22 December 1940, and they were seeded with spores three days later. Efforts were made to coax the mould into producing more penicillin. Heatley tried adding various substances to the medium, including sugars, salts, malts, alcohol and even marmite, without success. At the suggestion of Paul Fildes, he tried adding brewing yeast. This did not improve the yield either, but it did cut the incubation time by a third. The team also discovered that if the penicillin-bearing fluid was removed and replaced by fresh fluid, a second batch of penicillin could be prepared, but this practice was discontinued after eighteen months due to the danger of contamination. The mould had to be grown under sterile conditions.
Sources: en.wikipedia.org
== Geography == According to the United States Census Bureau, the city has an area of 2.70 square miles (6.99 km2); 2.67 square miles (6.92 km2) is land and 0.03 square miles (0.08 km2) is water. The Sauk River bisects Cold Spring from the southwest. Cold Spring is in Wakefield Township geographically but is a separate entity.
Osteocalcin, also known as bone gamma-carboxyglutamic acid-containing protein (BGLAP), is a small (49-amino-acid) noncollagenous protein hormone found in bone and dentin, first identified as a calcium-binding protein. Because osteocalcin has gla domains, its synthesis is vitamin K2–dependent. In humans, osteocalcin is encoded by the BGLAP gene. Its receptors include GPRC6A, GPR158, and possibly a third, yet-to-be-identified receptor. There is evidence that GPR37 might be the third osteocalcin receptor.
==== Anti-inflammatory treatments ==== Topical corticosteroids are effective in short-term treatment of seborrhoeic dermatitis and are as effective or more effective than antifungal treatment with azoles. These are sometimes used for a few weeks at a time. There is also evidence for the effectiveness of topical calcineurin inhibitors like tacrolimus and pimecrolimus as well as lithium salt therapy. Calcineurin inhibitors were also effective in reducing the growth of Malassezia, offering two routes by which they may treat seborrhoeic dermatitis. Medications such as calcineurin inhibitors are not often used in individuals with seborrhoeic dermatitis who are immunocompromised because they cause further immune suppression. Oral immunosuppressive treatment, such as with prednisone, has been used in short courses for seborrhoeic dermatitis, as a last resort due to its potential side effects.
== Names == The systematic name of this enzyme class is 17beta-hydroxysteroid:NAD+ 17-oxidoreductase. Other names in common use include 17-ketoreductase and 17beta-HSD. This enzyme participates in androgen and estrogen metabolism.
Sources: en.wikipedia.org
=== Niche uses === The polymer is also used to make Gro-Beast toys, which expand when placed in water, such as the Test Tube Aliens. Similarly, the absorbent properties of one of its copolymers can be utilized as an additive in body-powder. It has been used as a subdermal filler for aesthetic facial surgery It was also used in the synthesis of the first Boger fluid.
In February 2025, the firm announced a historic multi-year renewal of its long-term partnership with the Ultimate Fighting Championship, marking the largest sponsorship deal in the history of both companies. Several UFC champions have partnered with Monster Energy, including Conor McGregor, Justin Gaethje, Cain Velasquez, and Jon "Bones" Jones. In November 2012, the firm announced a long-term partnership with the Professional Bull Riders, and currently sponsors several riders including Jose Vitor Leme, Cody Teel, and Derek Kolbaba. Starting in 2018, they became the title sponsor of the PBR's premiership tour, known as the Unleash the Beast tour.
Sandra Ferry Rockefeller (1935–2024) John Davison "Jay" Rockefeller IV – a former U.S. Senator from West Virginia and a former two-term governor of that state Hope Aldrich Rockefeller Alida Ferry Rockefeller
Sources: en.wikipedia.org
It is a synthetic tetrapeptide. Its sequence was derived from research on peptide fractions of bovine pineal extract, and the intact AEDG sequence has not been demonstrated as an abundant free peptide in human tissue.
AEDG is the one-letter code for the four amino acids alanine, glutamate, aspartate and glycine in that order. The same molecule is written in three-letter form as Ala-Glu-Asp-Gly.
Identity is normally confirmed by mass spectrometry against the calculated mass of roughly 390.35 g/mol. Purity is then estimated by reversed-phase high-performance liquid chromatography with ultraviolet detection.
It is a four-amino-acid peptide built from alanine, glutamate, aspartate and glycine in that order. Its formula is C14H22N4O9, and it is made by chemical synthesis rather than extracted from tissue. The synthetic peptide is a single defined molecule, unlike the pineal extracts it is often compared with.