Compound monograph
GHK (Prezatide)
GHK is the uncomplexed tripeptide ligand of the GHK-copper complex, identified in 1977 as a growth-modulating tripeptide from human plasma.
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Identity & nomenclature
GHK is the uncomplexed tripeptide ligand of the GHK-copper complex, identified in 1977 as a growth-modulating tripeptide from human plasma.
GHK, GHK-Cu and Pal-GHK are three different substances: an uncomplexed peptide, a copper coordination species, and a covalently lipidated derivative. CAS 49557-75-7 belongs to THIS entry, the free tripeptide. The copper complex is 89030-95-5. That distinction has practical consequences — certificates of analysis in this market have carried the free-tripeptide number on copper-complex product, which describes the wrong substance.
Canonical name: Prezatide.
Declared aliases and development codes: GHK, Glycyl-L-histidyl-L-lysine, Tripeptide-1, NSC-379527.
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Molecular properties
| Molecular formula | C14H24N6O4 |
|---|---|
| Molecular mass | 340.38 Da |
| CAS Registry Number | 49557-75-7 |
| PubChem CID | 73587 |
| UNII | 39TG2H631E |
| One-letter sequence | GHK |
| Three-letter sequence | Gly–His–Lys |
| Terminal groups | Free N-terminus; Free C-terminal carboxyl |
Three residues with a free N-terminal amine and a free C-terminal carboxyl. No modifications. Copper is NOT part of this entry — see nomenclatureNotes.
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Structural characteristics
Its matrix provenance is sourced: proteolysis of SPARC, a matrix-associated protein, yields KGHK, GHK and longer peptides. That provenance is the basis for its secondary matrikine classification. Two cautions belong with it. Most of the angiogenic activity in that work mapped to KGHK rather than to the GHK tripeptide, and was reported as sequence-specific and apparently independent of bound copper — so neither the longer-fragment results nor a copper dependence should be transferred to GHK. Separately, spectroscopic work on Cu(II) coordination reports three nitrogen atoms and one oxygen in a square-planar arrangement, with the major and minor species present varying by pH. Copper binding is therefore established; a single invariant coordination structure is not.
Terminal features: Free N-terminus, Free C-terminal carboxyl.
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Molecular targets & mechanisms
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Analytical considerations
For material specified as uncomplexed GHK, quantitative metal analysis is an identity-relevant measurement rather than a cosmetic one — the peptide ion alone does not establish the absence of copper, and acidic chromatography can change the coordination state before detection. Any experiment described as copper-independent must also account for metals already present in the medium. Neither solution colour nor amino-acid composition establishes the complete identity.
Disagreements and mix-ups
Points where sources disagree about this compound's identity, or where a name or form is easily confused with another, as noted in this record. The discrepancy register quotes the passage for each one.
Often mixed up · Registry identifier
GHK and GHK-Cu: two substances, two CAS numbersAlso noted in GHK-Cu
Often mixed up · Name or substance
GHK, GHK-Cu and Pal-GHKAlso noted in Pal-GHK (Palmitoyl Tripeptide-1)
What the studies reported
Each finding describes one cited study in its stated model. These observations are specific to that study and do not establish effects in other settings.
Cell and tissue studies
SPARC in trypsin-digestion and tandem-mass-spectrometry assays
Lane et al. identified GHK after tryptic cleavage of SPARC by comparing the released peptide with a GHK standard in tandem mass spectrometry.
Reference [2]Bovine aortic endothelial cells in a cord-formation assay
Lane et al. observed little effect of GHK on endothelial cord number in bovine aortic endothelial cultures.
Reference [2]
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Verified bibliography
Cited studies by type
The 3 papers this record cites, counted by the kind of work each reports. A count is the size of this record's selection, not of the research that exists, and says nothing about results, safety, effectiveness or approval.
- In vitro1
- In vivo (subject not stated)1
- Chemical, structural or analytical; no biological model1
- Study type not determined1
A paper can report more than one kind of work. Each count opens those papers in the bibliography. Compare every record on the Evidence Map.
Reference 1
Growth-modulating serum tripeptide is glycyl-histidyl-lysine.Schlesinger DH, Pickart L, Thaler MM
Experientia · 1977-03-15 · Journal Article
currentReference 2
SPARC is a source of copper-binding peptides that stimulate angiogenesis.Lane TF, Iruela-Arispe ML, Johnson RS, Sage EH
The Journal of cell biology · 1994-05 · Journal Article
currentReference 3
N.m.r. and e.p.r. investigation of the interaction of copper(II) and glycyl-L-histidyl-L-lysine, a growth-modulating tripeptide from plasma.Laussac JP, Haran R, Sarkar B
The Biochemical journal · 1983-02-01 · Journal Article
current
Study models of these references
What kind of experiment each cited paper reports, taken from its abstract unless marked. Not a summary of results.
| Reference | Study models |
|---|---|
| Schlesinger DH et al. 1977 | No abstract available; study type not determined |
| Lane TF et al. 1994 | Study models reported: in vitro; in vivo (subject not stated) · from the abstract |
| Laussac JP et al. 1983 | Chemical, structural or analytical study; no biological model reported |
Compare
Record history
Published 2026-09-13.
- : Sequence and structure
- : Sequence and structure
Each entry names the parts of this record that changed on that date. Changes to links between records and to catalogue links are not listed. This history covers the tracked record fields; study findings are not listed here.
Cite this record: Purely Peptides Research Library. GHK (Prezatide). Published 2026-09-13; updated 2026-10-15. https://purelypeptides.org/research/compounds/ghk/
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Methodology & citation verification
Reference identity is checked against official PubMed metadata. Local deterministic receipts bind each normalized title and canonical metadata record to its verification date. Scientific values remain absent when an authoritative source has not been verified.
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