copper peptide comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2025-11-17. Numbers and descriptions here follow the published literature rather than marketing material.
Several names circulate for the same material, which complicates literature searches. Cosmetic ingredient lists often use copper tripeptide-1, while older biochemistry papers use glycyl-L-histidyl-lysine or its abbreviation GHK. The copper complex is sometimes written as GHK-Cu(II) to make the oxidation state explicit. Terminology is not fully standardized, so matching a compound across sources requires attention to the exact sequence, the counterion, and the stated copper content. Reviews that compare studies must account for these naming differences before drawing conclusions.
GHK-Cu is the copper(II) complex of the tripeptide glycyl-L-histidyl-L-lysine, a short sequence of three amino acids. The peptide was first isolated from human plasma in 1973 during research on factors that influence tissue repair in liver. Its ability to bind copper ions became a central point of interest because the metal changes the peptide's chemistry and its behaviour in laboratory systems. Today the compound appears in cosmetic formulations, cell-culture studies, and biochemistry literature under several names.
The peptide sequence places a histidine in the middle, and this residue dominates metal binding. Copper(II) coordinates through the imidazole nitrogen of histidine and the terminal amino group, forming a stable chelate ring system. Loss of the copper ion leaves the free tripeptide, which has different solubility and reactivity. This structural detail matters because assays that measure only the peptide backbone can miss whether copper is still bound to it.
Published work on GHK-Cu concentrates largely on cell culture systems rather than whole organisms. Frequently used endpoints include collagen synthesis, expression of matrix metalloproteinases, and migration of fibroblasts. Some reports describe antioxidant behavior, while others stress delivery of copper into cells. These mechanisms are proposed rather than demonstrated, and the relative weight of each pathway is unclear. Human trials are few and generally small, so laboratory findings should not be read as confirmed clinical results.
GHK-Cu is a coordination complex formed between the tripeptide glycyl-L-histidyl-L-lysine and a copper(II) ion. The peptide backbone consists of glycine, histidine, and lysine joined in that order. Copper is held through the imidazole nitrogen of histidine and the alpha-amino group at the N-terminus, which together produce a square-planar arrangement around the metal center. The solid appears blue to violet, a color that originates from d-d electronic transitions within the copper coordination sphere. The complex is indexed under CAS number 89030-95-5.
| Property | Value | Notes |
|---|---|---|
| Peptide sequence | Gly-His-Lys | Three amino acids, histidine in the middle |
| Complex formula | C14H22CuN6O4 | One copper(II) ion per peptide |
| Molar mass (complex) | approx. 402.9 g/mol | Depends on counterion and hydration state |
| Appearance | Blue to blue-violet solid | Colour arises from copper coordination |
| Common synonyms | Copper tripeptide-1, GHK-Cu | Naming varies between disciplines |
Purity assessment typically involves high-performance liquid chromatography for the peptide and atomic spectroscopy for copper content. The ratio of copper to peptide is a key quality parameter; a value near one indicates proper stoichiometry. Impurities can include free peptide, copper salts, and truncated sequences from synthesis. Because the complex is dynamic, sample preparation and mobile-phase conditions can shift the observed species. Reported purity values therefore depend on the analytical method and should be interpreted with that context.
Characterizing GHK-Cu requires methods that distinguish the intact complex from free peptide and unbound copper. UV-visible absorption around 600 nm provides a rapid check for copper coordination, while circular dichroism reports on peptide secondary structure. Mass spectrometry confirms the peptide mass and can detect copper adducts under carefully controlled conditions. Electron paramagnetic resonance is particularly informative for Cu(II) because it reveals the ligand field symmetry. No single technique fully defines the complex, so laboratories combine orthogonal methods.
Stability of GHK-Cu in solution depends on pH, temperature, buffer composition, and oxygen exposure. The copper center can undergo reduction or dissociation, especially in the presence of strong metal chelators such as EDTA. Aqueous solutions are often prepared fresh or stored frozen to limit degradation. Lyophilized solid is more stable than liquid formulations, but it can absorb moisture and should be kept dry. Light exposure may also affect copper complexes, though the effect is often modest.
Analytical verification commonly relies on high-performance liquid chromatography for purity assessment and mass spectrometry for identity confirmation. Spectroscopic methods such as UV-visible absorption and electron paramagnetic resonance can probe the metal centre itself, since the d9 configuration of copper(II) produces characteristic signals. Elemental analysis or plasma-based techniques quantify copper content. Because each method reports a different aspect of the same sample, purity figures are most meaningful when the technique and its detection wavelength are stated alongside the value.
Stability of the complex in solution depends on pH, temperature, and the presence of competing ligands. It is generally described as more resistant to breakdown than the metal-free chain, since coordination reduces susceptibility to enzymatic attack. Oxidation and hydrolysis can nevertheless proceed over time in aqueous media. Storage guidance in laboratory settings commonly involves refrigeration, protection from light, and avoidance of strongly alkaline conditions. Published data on long-term behaviour vary considerably and depend on the specific matrix.
Handling practices for the solid material emphasise low temperature and dryness. The lyophilised or powdered form is typically kept at refrigerator or freezer temperatures together with a desiccant. Working solutions are often prepared fresh, because repeated freeze-thaw cycles and extended storage may alter the complex. Glass or inert plastic containers are preferred over materials that could leach metal ions into the preparation. Such practices follow general peptide conventions rather than substance-specific regulations.
=== Diet === In the wild, the croaking gourami is mostly insectivorous, feeding on insects and insect larvae. However, other food types, such as zooplankton, crustaceans, shrimp meat and plant matter, are eaten as well. In aquaria, a varied diet is recommended: standard flake foods along with regular supplements of freeze-dried bloodworms, tubifex worms, brine shrimp, and some algae-based flakes will provide the fish with proper nutrition. Occasional feedings of live brine shrimp offer the aquarist an opportunity to observe the natural hunting behaviour of this species.
The Shroud of Turin (Italian: Sindone di Torino), also known as the Holy Shroud (Italian: Sacra Sindone), is a length of linen cloth that bears a faint image of the front and back of a naked man. Because details of the image are consistent with traditional depictions of Jesus of Nazareth after his death by crucifixion, the shroud has been venerated by Christians for centuries, especially by members of the Catholic Church, as Jesus's shroud upon which his image was miraculously imprinted. The human image on the shroud can be discerned more clearly in a black-and-white photographic negative than in its natural sepia colour, an effect discovered in 1898 by Secondo Pia, who produced the first photographs of the shroud. This negative image is associated with a popular Catholic devotion to the Holy Face of Jesus. The documented history of the shroud dates back to 1354, when it began to be exhibited in the new collegiate church of Lirey, a village in north-central France. The shroud was denounced as a forgery by the bishop of Troyes, Pierre d'Arcis, in 1389. It was acquired by the House of Savoy in 1453 and later deposited in a chapel in Chambéry, where it was damaged by fire in 1532. In 1578, the Savoys moved the shroud to their new capital in Turin, where it has remained ever since. In 1694, it was moved to the altar in the Chapel of the Holy Shroud, which was designed for that purpose by the architect Guarino Guarini and which is connected to both the royal palace and the Turin Cathedral. It remained there until 1993, when it was moved to the cathedral.
=== Genome === Chinese scientists published a draft genome of Ginkgo biloba in 2016. The tree has a large genome of 10.6 billion DNA nucleobase "letters" (the human genome has three billion) and about 41,840 predicted genes which enable a considerable number of antibacterial and chemical defense mechanisms. 76.58% of the assembled sequence turned out to be repetitive sequences. In 2020, a study in China of ginkgo trees up to 667 years old showed little effects of aging, finding that the trees continued to grow with age and displayed no genetic evidence of senescence, and continued to make phytochemicals indefinitely.
These frequent long treatments are often done at home while sleeping, but home dialysis is a flexible modality and schedules can be changed day to day, week to week. In general, studies show that both increased treatment length and frequency are clinically beneficial. Hemo-dialysis was one of the most common procedures performed in U.S. hospitals in 2011, occurring in 909,000 stays (a rate of 29 stays per 10,000 population).
== See also == Philippine resistance against Japan Philippine Constabulary (PC) Military history of the Philippines List of American guerrillas in the Philippines Thomas Flynn (Columban priest) Communist rebellion in the Philippines
Sources: en.wikipedia.org
== Properties == The fungus Aspergillus fumigatus is capable of incorporating tellurocysteine (and telluromethionine) into proteins when grown in appropriate media. When incorporated into glutathione transferase, tellurocysteine efficiently inhibits aminoacylation and increases the efficiency of glutathione peroxidase.
=== Decriminalization and personal use === In 1976, the Netherlands' policy of tolerance of limited cannabis sale and personal use came into practice. The Dutch government amended the country's Opium Act to consider cannabis as a "soft drug" and permitted gedoogbeleid (Dutch: "tolerance policy"). Trafficking and possession of cannabis remained illegal; cannabis laws were not enforced for sale of small quantities for on-site use in coffeeshops. The INCB criticism of the Dutch system has been ongoing. One annual report called it "an activity that might be described as indirect incitement. This is not in accordance with the spirit or the letter of the international drug control treaties." In 2001, Portugal decriminalized purchase and possession for personal use of all psychoactive drugs. It maintained its treaty obligations by changing the form of prohibition from criminal law to administrative law, replacing criminal penalties with fines, reporting requirements, and treatment referrals; drugs still had to be obtained from illegal sources, as selling remained a criminal act. Initially taking a negative view, the INCB in 2005 accepted the policy as legitimate, finding that "the practice of exempting small quantities of drugs from criminal prosecution is consistent with the international drug control treaties". Some two dozen countries have taken similar approaches to decriminalizing cannabis and other drugs for personal consumption.
== Awards and honors == Agnes Fay Morgan Research Award, Iota Sigma Pi, 2019 Marshall University College of Science Distinguished Alumni Award, 2019 Eli Lilly Young Investigator Award in Analytical Chemistry, 2018 US HUPO Robert J. Cotter New Investigator Award, 2018 NSF CAREER Award, 2015 Arthur C. Neish Young Investigator Award, 2014 NSF Graduate Research Fellowship, 2002-2005
In 1933, the French pharmaceutical company Laboratoires Rhône-Poulenc began to search for new antihistamines. In 1947, it synthesized promethazine, a phenothiazine derivative, which was found to have more pronounced sedative and antihistaminic effects than earlier drugs. A year later, the French surgeon Pierre Huguenard used promethazine together with pethidine as part of a cocktail to induce relaxation and indifference in surgical patients. Another surgeon, Henri Laborit, believed the compound stabilized the central nervous system by causing "artificial hibernation" and described this state as "sedation without narcosis". He suggested to Rhône-Poulenc that they develop a compound with better-stabilizing properties. In December 1950, the chemist Paul Charpentier produced a series of compounds that included RP4560 or chlorpromazine. Chlorpromazine was distributed for testing to physicians between April and August 1951. Laborit trialled the medicine at the Val-de-Grâce military hospital in Paris, using it as an anaesthetic booster in intravenous doses of 50 to 100 mg in surgery patients and confirming it as the best drug to date in calming and reducing shock, with patients reporting improved well being afterward. He also noted its hypothermic effect and suggested it may induce artificial hibernation. Laborit thought this would allow the body to better tolerate major surgery by reducing shock, a novel idea at the time. Following on, Laborit considered whether chlorpromazine may have a role in managing patients with severe burns, Raynaud's phenomenon, or psychiatric disorders.
== Deaths == 18 January – Sir David Cox, English statistician (b. 1924) 15 March – Eugene Parker, American solar and plasma physicist (b. 1927) 20 March – Wen Shengchang, Chinese oceanographer and member of the Chinese Academy of Sciences (b. 1921) 23 March – Arthur Riggs, American geneticist (b. 1939) 27 March – Martin Pope, American physical scientist (b. 1918) 27 March – James Vaupel, American demographer and aging researcher (b. 1945) 29 March – Paul Benioff, American physicist of quantum computing (b. 1930) 30 March – Kenneth Walters, British mathematician and rheologist (b. 1934) 1 April – Gerhard J. Woeginger, Austrian mathematician. 5 April – Sidney Altman, Canadian-American molecular biologist, Nobel Prize laureate (1989). 5 April – Bjarni Tryggvason, Icelandic-born Canadian astronaut (STS-85). 5 April – Eelco Visser, Dutch computer scientist. 5 April – Leslie Young, New Zealand economist. 1 May – Ray Freeman, British chemist. 1 May – Dominique Lecourt, French philosopher. 2 May – Joseph Raz, Israeli philosopher. 4 May – Amanda Claridge, Canadian archaeologist. 7 May – Sir Paul Mellars, British archaeologist. 8 May – Harry Dornbrand, American aerospace engineer. 8 May – Zhuang Qiaosheng, Chinese geneticist and wheat breeder, member of the Chinese Academy of Sciences. 9 May – John H. Coates, Australian mathematician. 14 May – Bernard Bigot, French physicist and civil servant, director general of ITER (b. 1950) 9 June – Gordon M. Shepherd, American neuroscientist. 26 July – James Lovelock, English environmentalist (Gaia hypothesis) and futurist (b.
Sources: en.wikipedia.org
=== Chemical labeling === Chemical labeling or the use of chemical tags utilizes the interaction between a small molecule and a specific genetic amino acid sequence. Chemical labeling is sometimes used as an alternative for GFP. Synthetic proteins that function as fluorescent probes are smaller than GFP's, and therefore can function as probes in a wider variety of situations. Moreover, they offer a wider range of colors and photochemical properties. With recent advancements in chemical labeling, Chemical tags are preferred over fluorescent proteins due to the architectural and size limitations of the fluorescent protein's characteristic β-barrel. Alterations of fluorescent proteins would lead to loss of fluorescent properties.
Within the empire, 65% of the territory and 62% of the population belonged to Prussia. The Treaty of Versailles at the end of World War I stripped the former German Empire of 12 to 13 percent of its land area and population, the majority of it from Prussia. Only Alsace–Lorraine, which had never attained full statehood, was wholly lost to Germany. The new Weimar Republic remained federal in nature, with a total of 17 states. Seven small states in east-central Germany consolidated into Thuringia in 1920, Coburg chose to merge into Bavaria (also in 1920), and Prussia absorbed Pyrmont and Waldeck (1921 and 1929). During the Weimar period, there were a number of unsuccessful proposals to make radical changes to Germany's state structure, seven short-lived unrecognized states, four of them self-declared soviet republics during the German revolution of 1918–1919, plus two separatist republics in the Rhineland in 1923/24. After the Nazi Party seized power in January 1933, the states were gradually abolished and reduced to provinces under the Nazi regime via the Gleichschaltung process, as the states administratively were largely superseded by the Nazi Gau system. Three changes are of particular note: on 1 January 1934, Mecklenburg-Schwerin was united with neighbouring Mecklenburg-Strelitz; and, by the Greater Hamburg Act (Groß-Hamburg-Gesetz) of 1937, the territory of the city-state was extended, while Lübeck lost its independence and became part of the Prussian province of Schleswig-Holstein.
The difference in the COP of the blood and tissue tends to favor the reentry of fluid from the extravascular space, into the circulatory system. This tendency is opposed by the venous hydrostatic pressure, which tends to favor the exit of fluid from small vessels, into the interstitial space. The low protein theory for the pathogenesis of kwashiorkor held that a deficiency of serum proteins, caused by inadequate protein intake, disrupted this balance, and thus impaired the return flow of fluid from the interstitium into the capillary and venous structures. It has been taught that this is what accounts for the accumulation of extravascular fluid in kwashiorkor, and the subsequent pedal edema and abdominal distension. The low protein theory, which relies heavily upon Starling's theory for the movement of fluid in biological systems, provided a compelling rationale for the pathogenesis of edema in kwashiorkor. What it does not explain, however, is the entire array of disturbances that define the kwashiorkor syndrome. These include irritability, anorexia, skin desquamation, skin depigmentation, hair discoloration, reduced mitochondrial respiration, impaired lipid export from the liver without an accompanying reduction of lipoprotein synthesis, 'oxidative stress', glutathione depletions, transsulfuration disturbances, diffuse DNA hypomethylation, immune dysfunction, decreased transmethylation activity, and sulfated glycosaminoglycan deficiencies.
The GABAA receptor agonist gaboxadol (THIP; LU-2-030), a synthetic derivative of the neurotransmitter γ-aminobutyric acid (GABA) and an analogue of the alkaloid muscimol, underwent formal clinical development for the treatment of insomnia and reached phase 3 clinical trials for this indication in the 1990s and 2000s. It was found to effectively improve sleep onset and duration in people with insomnia. In addition, and unlike other hypnotics like benzodiazepines, gaboxadol improved slow wave sleep, preserved sleep architecture, and did not suppress REM sleep. Moreover, in contrast to benzodiazepines, tolerance did not appear to develop to gaboxadol's hypnotic effects. The development of gaboxadol was discontinued in 2007. This was due to high rates of psychiatric and hallucinogenic effects in drug users at supratherapeutic doses, failure of a 3-month efficacy trial, and other cited reasons. Moreover, there was tension concerning hypnotics in the pharmaceutical industry at the time owing to bizarre reports of zolpidem (Ambien)-induced delirium that emerged in the media in 2006, which may have made the developer of gaboxadol more concerned about potential liability issues. According to journalist Hamilton Morris, the discontinuation of gaboxadol's late-stage development may have deprived people with insomnia access to an effective, safe, and non-addictive treatment. There has been some further study of gaboxadol as a hypnotic by David Nutt and colleagues following the discontinuation of its development.
=== Inhibitor of mitochondrial permeability transition pore === It has also been shown that the compound inhibits mitochondrial permeability transition pore (MPTP) by inhibiting the activity of the pore regulator, cyclophilin D (CyP-D). CyP-D is a peptidyl-prolyl cis-trans isomerase or protein that causes a proline residue in a peptide to switch from its trans isomer to its cis isomer. Studies have been done using the Calcium retention capacity (CRC) assay on mouse liver mitochondria in order to measure antamanide's effect on the permeability transition pore. The data from this experiment showed that antamanide inhibits pore opening like the known inhibitors CsA and Ubiquinone 0. It has been found that altering the 6 and 9 positions in the cyclic peptide ring disables the inhibitory effect on the pore by the drug. A study has also been to determine whether the antamanide also inhibits the apoptosis (programmed cell death) of human cervical carcinoma cells caused by the permeability transition pore. The results showed an inhibitory response. Studying for inhibitors of MPTP is important because MPTP induction is connected to many diseases, such as muscular dystrophies (a disease that weakens the musculoskeletal system), hepatotoxicity (chemical caused liver damage), and ischemic injury of the kidneys (injury causing restriction of blood supply to the kidneys).
Sources: en.wikipedia.org
The peptide is glycyl-L-histidyl-L-lysine, a three-amino-acid sequence commonly abbreviated GHK. It binds a single copper(II) ion under typical laboratory conditions. The free peptide and the copper complex are separate chemical species with different properties.
The sequence was identified in human plasma in 1973. Early work examined its presence in blood and its proposed role in tissue repair. The copper-binding property was characterized afterward and became the focus of much later research.
The tripeptide has been measured in human plasma and other biological fluids. Whether it circulates mainly as the copper complex or as the free peptide remains an open question. Natural concentrations are low and difficult to measure reliably.
It is the copper complex of the tripeptide glycyl-L-histidyl-lysine. The metal ion is held by the histidine imidazole group and the peptide N-terminus. Most research on it concerns skin and wound models.