This is a working overview of glycyl-histidyl-lysine, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2025-07-20. Anything still debated is marked as such rather than presented as settled.
The peptide portion consists of three amino acids: glycine, histidine and lysine. Copper(II) coordinates through the imidazole nitrogen of histidine, the alpha-amino group of glycine and a deprotonated amide nitrogen of the backbone, producing a roughly square-planar geometry. This arrangement gives the complex its characteristic blue-to-violet colour and helps it resist dissociation in water. Reported stability constants are high, although values differ between studies because of differences in ionic strength and measurement method.
The International Nomenclature of Cosmetic Ingredients lists the substance as copper tripeptide-1, the name that appears on most topical product labels. Related designations include copper peptide and GHK-Cu, and the hyphenated form is common in research literature. In cosmetics the material is regulated as an ingredient rather than as a drug, so products may reach the market without evidence of the effects claimed for them. Whether those effects are clinically meaningful is an open question, since most supportive data come from laboratory work and small trials.
GHK-Cu is the copper complex of the tripeptide glycyl-L-histidyl-L-lysine, a short sequence found naturally in human plasma, saliva and urine. Loren Pickart reported the isolation of the free peptide in 1973 while studying factors that influenced the growth of aged liver cells in culture. The peptide was later shown to bind copper(II) with high affinity, and the metal-bound form became the focus of most subsequent research. Its concentration in circulation declines markedly with age, a pattern that is well documented, though the physiological consequences of that decline remain debated.
GHK-Cu is a coordination complex formed between the tripeptide glycyl-L-histidyl-lysine and a copper(II) ion. The peptide sequence is conventionally written as Gly-His-Lys, abbreviated GHK. Copper binds through the imidazole nitrogen of histidine, the alpha-amino group, and a deprotonated amide nitrogen, producing a square-planar geometry. The complex carries a net positive charge near physiological pH and is intensely blue in aqueous solution. The metal-free peptide is often written simply as GHK, while the copper-bound form is written GHK-Cu.
The compound was first isolated from human plasma by the biochemist Loren Pickart in 1973. Early work identified it as a factor that altered the behavior of cultured liver cells, and later studies linked it to connective tissue and wound-related processes. Reported plasma concentrations fall markedly between roughly age twenty and age sixty, a pattern that generated interest in copper peptide biology. Whether that decline has functional consequences remains an open question, because differences observed across age groups do not by themselves establish causation. Research interest later expanded into cosmetic and tissue-culture settings.
Mechanistic accounts focus on how the complex delivers copper and how the released peptide interacts with the extracellular matrix. Copper is an essential cofactor for lysyl oxidase and other enzymes involved in collagen and elastin cross-linking, and GHK is one of several peptides able to carry the metal. Reported effects include altered gene expression in fibroblasts and changes in matrix metalloproteinase activity, although many of these findings come from cell culture rather than whole organisms. The relative contribution of the peptide backbone, the copper ion, and downstream copper metabolism is not fully resolved.
| Property | Value | Notes |
|---|---|---|
| INCI name | Copper tripeptide-1 | Standard designation on cosmetic ingredient labels |
| Peptide sequence | Gly-His-Lys | Three-residue ligand; binding occurs at the histidine side chain |
| Metal-to-peptide ratio | 1 to 1 | One copper(II) ion per peptide unit |
| Appearance | Blue to violet powder | Colour arises from copper-to-peptide electronic transitions |
| Water solubility | Freely soluble | Commonly formulated in aqueous or water-alcohol systems |
The tripeptide was first isolated from a human plasma filtrate in 1973 during studies of tissue repair factors. Later work detected the free peptide and its copper complex in saliva, urine, and wound fluid, suggesting a natural role in tissue remodeling. Plasma concentrations reported in early literature decline with age, a pattern often cited in discussions of skin aging. Whether these endogenous levels are directly functional or largely incidental remains an open question. The peptide sequence is conserved across mammalian species.
Material described in research and cosmetic supply chains is typically a synthetic peptide supplied as a lyophilized powder. Purity is commonly reported through chromatographic separation, often at 95 percent or higher, while copper content is confirmed by separate elemental analysis. Batch variation in color and solubility can reflect residual counter-ions, moisture, or partial oxidation of the peptide. Because the complex is not a single regulatory entity, specifications differ between suppliers and are not standardized internationally.
GHK-Cu is a coordination complex formed between the tripeptide glycyl-L-histidyl-L-lysine and a copper(II) ion. The peptide binds copper through its histidine imidazole nitrogen, its terminal amino group, and a deprotonated amide nitrogen, creating a stable chelate ring. The resulting complex carries a distinctive blue to blue-violet color, which arises from copper d-d electronic transitions. In the solid state it is usually handled as a powder, while in solution the complex can dissociate and re-form depending on pH and competing ligands. The name copper tripeptide-1 is widely used in ingredient listings.
GHK-Cu is a coordination complex formed between the tripeptide glycyl-L-histidyl-L-lysine and a copper(II) ion. The peptide sequence is often abbreviated Gly-His-Lys, and the copper is bound through the histidine imidazole nitrogen and adjacent peptide nitrogens. The complex is frequently described as a 1:1 peptide-to-copper species. It occurs naturally in human plasma, saliva, and urine at low concentrations. Its endogenous levels have been reported to decline with age, although the precise physiological role of that change remains an open question.
Research interest in GHK-Cu centers on its ability to deliver copper and to influence cellular processes in laboratory models. In cell culture and animal studies, the complex has been linked to collagen synthesis, antioxidant enzyme activity, and expression of genes associated with tissue remodeling. These effects are not equivalent to proven clinical outcomes. The mechanisms proposed include copper transfer to cuproenzymes, modulation of growth factor signaling, and interactions with extracellular matrix components. How much of the observed activity depends on intact GHK-Cu versus free copper or free peptide is not fully resolved.
The compound entered scientific literature in the 1970s, when plasma factors with copper-binding activity were isolated and characterized. Later work expanded into wound healing, skin biology, and cosmetic formulation, where copper tripeptide-1 became a recognized ingredient name. Most published studies remain preclinical or small-scale, and findings are often reported in specialized dermatology or peptide journals. Regulatory treatment varies: some jurisdictions allow it as a cosmetic ingredient, while research-grade material is sold for laboratory use. Questions about optimal delivery, target tissues, and long-term effects continue to be investigated rather than settled.
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.
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.
== Economic significance == In 2024, South Africa's logistics sector contributed R518.4 billion towards the country's GDP, a year-over-year increase of 4.3%. South Africa's logistics sector is expected to grow at a CAGR of 9.1% from 2026 to 2033. In 2025, the country accounted for 2.3% of the global logistics market. In 2026, South Africa's logistics sector was growing the fastest out of all countries in the Middle East & Africa region. Examples from Wesgro of the South African logistics sector's impact on the country's economy as a whole are in the table below.
=== Illegal drug trafficking === Drug trafficking sales have gone up in Colombia since the 1970s due to the conflict. Many Mexican drug cartels have been spotted operating in the area, including the Sinaloa Cartel, Gulf Cartel, Beltrán Leyva Cartel, CJNG, and Los Zetas. The Medellín Cartel and Cali Cartel were the first drug trafficking organizations in Colombia and had alliances with the Guadalajara Cartel, Los Valencia Organization, and Amezcua Cartel.
The giant puffball, Calvatia gigantea, reaches 1 foot (0.30 m) or more in diameter, and is difficult to mistake for any other fungus. It has been estimated that, when mature, a large specimen of this fungus will produce around 7 × 1012 spores, which is more than any other known organism. Some puffball mushrooms may also be stalked, such as those found in the genus Tulostoma. There are also a number of false puffballs that look similar to the true ones.
Sources: en.wikipedia.org
Despite never having attended college – or any formal schooling beyond high school – Rathbun had authored more than 80 scientific publications, described over 674 new species of crustacean, and developed a system for crustacean-related records at the Smithsonian Museum. 1917: Dutch biologist and phytopathologist Johanna Westerdijk became the first female university professor in the Netherlands. She was appointed an extraordinary professor of phytopathology at the University of Utrecht. 1918: German physicist and mathematician Emmy Noether created Noether's theorem explaining the connection between symmetry and conservation laws. 1919: Dutch biologist and geneticist Jantina Tammes became the university professor in the Netherlands. She was appointed an extraordinary professor of variability and heredity at the University of Groningen. She became the first person in the Netherlands to occupy a chair in genetic. Moreover, she became the second female professor in the country, and the first one at the University of Groningen. She held this position until 1937, when she resigned at the age of sixty-six. 1919: Chilean engineer Justicia Espada Acuña graduates from Universidad de Chile, becoming the first woman with degree in civil engineering in South America 1919: Kathleen Maisey Curtis became the first New Zealand woman to earn a Doctorate of Science degree (DSc), completing her thesis on Synchytrium endobioticum (potato wart disease) at the Imperial College of Science and Technology.
==== Viral ==== Mice pretreated for 4 weeks with diets that raised their intestinal SCFAs levels had reduced viral levels and pulmonary inflammation during the course of respiratory syncytial virus infection; these reductions did not occur in Ffar2 gene knockout mice or mice pretreated with antibiotics to reduce their intestines' SCFAs levels. Thus, SCFA activated FFAR2 appeared to reduce the severity of this viruses infection in mice. Different results were found in a study examining influenza A virus's ability to enter and thereby infect human A549 lung cancer cells and mouse 264RAW .7 macrophages. Reduction of FFAR2 using gene knockdown methods reduced the virus's ability to enter into both cell types. Treating A549 cells with FFAR2 agonists, either 4-CMTB or compound 58, also inhibited the virus's entry into these cells. Analysis of this inhibition revealed that Influenza A virus entered these cells by binding to their surface membrane sialic acid receptors; this binding triggered endocytosis, i.e., internalization, of these cells' sialic acid receptors along with their attached viruses. A portion of the sialic acid receptor-bound virus also binds to and activates FFAR 2; this activation increased the endocytosis triggered by the virus's binding to the sialic acid receptors. 4-CMTB and Compound 58 acted to block the ability of the sialic acid-bound virus to enhance endocytosis.
These diseases can be difficult to diagnose due to the close relation of the musculoskeletal system to other internal systems. The musculoskeletal system refers to the system having its muscles attached to an internal skeletal system and is necessary for humans to move to a more favorable position. Complex issues and injuries involving the musculoskeletal system are usually handled by a physiatrist (specialist in physical medicine and rehabilitation) or an orthopaedic surgeon.
Guzmán later examined Peck's herbarium specimen, and in his comprehensive 1983 monograph on Psilocybe, concluded that Peck had misidentified it with the species now known as Panaeolina foenisecii. P. semilanceata is much less common in South America, where it has been recorded in Chile. It is also known in Australia (where it may be an introduced species) and New Zealand, where it grows in high-altitude grasslands. In 2000, it was reported from Golaghat, in the Indian state of Assam. In 2017, it was reported from Charsadda, in the Pakistani province of Khyber Pakhtunkhwa.
Sources: en.wikipedia.org
It is a complex of a three-amino-acid peptide, glycine, histidine and lysine, bound to a single copper(II) ion. The metal is held mainly by the histidine side chain and the peptide backbone. Most commercial material is supplied as an acetate salt rather than as the free complex.
The free peptide was reported in 1973 by Loren Pickart, who isolated it from human plasma. Its copper-binding behaviour was characterised over the following years. The metal-bound form has been the subject of most later research.
Yes. Copper tripeptide-1 is the name used in cosmetic ingredient labelling, while GHK-Cu is the shorthand found in the scientific literature. Both refer to the same peptide-copper complex, and the two terms are interchangeable in most technical documents.
It is the copper(II) complex of the tripeptide glycyl-L-histidyl-lysine, a sequence of three amino acids. The copper ion is held by the histidine imidazole, the terminal amino group, and an amide nitrogen. The bound form is distinct from the free peptide in charge, color, and stability.