If you have been reading about Endogenous peptide and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2026-08-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
Laboratory studies describe GHK-Cu as a source of copper that cells can take up, with reported effects on collagen, elastin, and glycosaminoglycan synthesis in cultured fibroblasts. The peptide also appears in wound-repair research, where it is linked to the activity of matrix metalloproteinases and their inhibitors. These observations come largely from cell and animal models. How directly the complex controls any single pathway in intact human skin remains an open question, and reported effects depend on concentration, vehicle, and exposure time.
Copper takes part in redox chemistry, and the same property that makes it useful in enzymes can generate reactive oxygen species when the ion is loosely bound. GHK chelates copper through imidazole, amino, and amide nitrogen donors, which reduces the amount of free copper in solution. Whether that chelation is protective, neutral, or harmful in a given tissue is not settled. Laboratory assays report both antioxidant and pro-oxidant behavior, depending on the conditions and the readout used.
Published work on GHK-Cu is dominated by in vitro experiments and small animal studies. Human trials tend to be short and small, with endpoints such as skin appearance rather than clinical outcomes. Review articles often summarize the same underlying laboratory findings, which can make the evidence base look broader than it is. Several basic questions remain open: the concentration of the intact complex in human tissue, the route by which it crosses the skin barrier, and whether effects seen in culture produce measurable changes in people.
The sequence now called GHK was first reported in the early 1970s after isolation from human plasma, where it was noted to influence liver cell behavior in laboratory preparations. Later work described a copper-binding form and its activity in fibroblast and wound-model experiments. Review articles frequently group the substance with other copper peptides. Concentrations in blood appear to fall with age in several small surveys, although the reason for this trend is not settled. Whether such a decline carries functional consequences remains an open question.
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 |
|---|---|---|
| Copper binding sites | Imidazole, amino, and amide nitrogens | Form chelate rings with Cu(II) |
| Conditional binding constant | Reported near 10^16 at neutral pH | Value depends on method and medium |
| Visible absorption | Broad band in the blue-violet region | Source of the characteristic color |
| Common analytical methods | LC-MS, HPLC, UV-Vis, ICP-OES | Used for identity and copper content |
| Main degradation routes | Oxidation, photolysis, hydrolysis | Accelerated by light, heat, and pH extremes |
Analytical verification typically combines reversed-phase high-performance liquid chromatography with ultraviolet-visible detection. The copper complex absorbs visible light near 600–630 nm, giving a characteristic blue signal. Mass spectrometry confirms molecular mass and can detect free peptide or mismatched copper stoichiometry. Copper content is often measured independently by inductively coupled plasma mass spectrometry or atomic absorption spectroscopy. Purity, counterion identity, and residual solvents are additional quality-control parameters that methods may address.
Solid GHK-Cu is generally stored as a dry powder under frozen conditions to limit degradation. The peptide bond can hydrolyze, and the copper center can be displaced by strong chelators such as EDTA. Aqueous solutions are less stable than the solid and may lose color or form precipitates over time. Temperature, pH, and oxygen exposure are the main variables that affect shelf life. Neutral to slightly acidic conditions tend to preserve the complex better than strongly alkaline media.
Routine handling calls for minimizing freeze-thaw cycles and preparing solutions shortly before use. Glass or inert plastic containers reduce adsorption and metal leaching. Working stocks are often kept at 2–8 °C for short periods, while long-term reference material stays at −20 °C or below. Light protection is prudent because prolonged exposure may accelerate oxidation of the peptide. Documentation of lot number, concentration, and preparation date supports reproducibility in laboratory work.
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.
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.
===== MeSH D08.811.913.696 – phosphotransferases (EC 2.7) ===== MeSH D08.811.913.696.175 – diphosphotransferases MeSH D08.811.913.696.175.300 – gtp pyrophosphokinase MeSH D08.811.913.696.175.650 – ribose-phosphate pyrophosphokinase MeSH D08.811.913.696.175.825 – thiamin pyrophosphokinase MeSH D08.811.913.696.310 – myosin type iii MeSH D08.811.913.696.445 – nucleotidyltransferases MeSH D08.811.913.696.445.035 – n-acylneuraminate cytidylyltransferase MeSH D08.811.913.696.445.184 – choline-phosphate cytidylyltransferase MeSH D08.811.913.696.445.308 – dna nucleotidyltransferases MeSH D08.811.913.696.445.308.300 – dna-directed dna polymerase MeSH D08.811.913.696.445.308.300.112 – dna polymerase beta MeSH D08.811.913.696.445.308.300.225 – dna polymerase i MeSH D08.811.913.696.445.308.300.230 – dna polymerase ii MeSH D08.811.913.696.445.308.300.235 – dna polymerase iii MeSH D08.811.913.696.445.308.300.750 – RNA-directed dna polymerase MeSH D08.811.913.696.445.308.300.750.375 – hiv-1 reverse transcriptase MeSH D08.811.913.696.445.308.300.750.750 – telomerase MeSH D08.811.913.696.445.308.300.875 – taq polymerase MeSH D08.811.913.696.445.308.325 – dna nucleotidylexotransferase MeSH D08.811.913.696.445.400 – glucose-1-phosphate adenylyltransferase MeSH D08.811.913.696.445.600 – nicotinamide-nucleotide adenylyltransferase MeSH D08.811.913.696.445.625 – 2',5'-oligoadenylate synthetase MeSH D08.811.913.696.445.650 – polynucleotide adenylyltransferase MeSH D08.811.913.696.445.692 – rec a recombinases MeSH D08.811.913.696.445.735 – rna nucleotidyltransferases MeSH D08.811.913.696.445.735.265 – dna, catalytic MeSH D08.811.913.696.445.735.270 – dna-directed rna polymerases MeSH D08.811.913.696.445.735.270.375 – dna primase MeSH D08.811.913.696.445.735.270.750 – rna polymerase i MeSH D08.811.913.696.445.735.270.762 – rna polymerase ii MeSH D08.811.913.696.445.735.270.775 – rna polymerase iii MeSH D08.811.913.696.445.735.270.887 – rna polymerase sigma 54 MeSH D08.811.913.696.445.735.532 – polyribonucleotide nucleotidyltransferase MeSH D08.811.913.696.445.735.630 – q beta replicase MeSH D08.811.913.696.445.735.720 – rna helicases MeSH D08.811.913.696.445.735.720.500 – eukaryotic initiation factor-4a MeSH D08.811.913.696.445.735.780 – rna replicase MeSH D08.811.913.696.445.735.917 – rna, ribosomal, self-splicing MeSH D08.811.913.696.445.800 – sulfate adenylyltransferase MeSH D08.811.913.696.445.825 – transposases MeSH D08.811.913.696.445.825.500 – hiv integrase MeSH D08.811.913.696.445.837 – transposon resolvases MeSH D08.811.913.696.445.850 – UDP-glucose—hexose-1-phosphate uridylyltransferase MeSH D08.811.913.696.445.875 – UTP—glucose-1-phosphate uridylyltransferase MeSH D08.811.913.696.445.900 – UTP—hexose-1-phosphate uridylyltransferase MeSH D08.811.913.696.445.950 – vdj recombinases MeSH D08.811.913.696.620 – phosphotransferases (alcohol group acceptor) MeSH D08.811.913.696.620.010 – adenosine kinase MeSH D08.811.913.696.620.155 – choline kinase MeSH D08.811.913.696.620.175 – deoxycytidine kinase MeSH D08.811.913.696.620.200 – diacylglycerol kinase MeSH D08.811.913.696.620.225 – fructokinases MeSH D08.811.913.696.620.225.850 – phosphofructokinases MeSH D08.811.913.696.620.225.850.500 – phosphofructokinase-1 MeSH D08.811.913.696.620.225.850.500.249 – phosphofructokinase-1, liver type MeSH D08.811.913.696.620.225.850.500.500 – phosphofructokinase-1, muscle type MeSH D08.811.913.696.620.225.850.500.750 – phosphofructokinase-1, type c MeSH D08.811.913.696.620.225.850.750 – phosphofructokinase-2 MeSH D08.811.913.696.620.240 – galactokinase MeSH D08.811.913.696.620.250 – glucokinase MeSH D08.811.913.696.620.275 – glycerol kinase MeSH D08.811.913.696.620.300 – hexokinase MeSH D08.811.913.696.620.475 – kanamycin kinase MeSH D08.811.913.696.620.525 – 1-phosphatidylinositol 3-kinase MeSH D08.811.913.696.620.550 – 1-phosphatidylinositol 4-kinase MeSH D08.811.913.696.620.650 – phosphoenolpyruvate sugar phosphotransferase system MeSH D08.811.913.696.620.680 – polynucleotide 5'-hydroxyl-kinase MeSH D08.811.913.696.620.682 – protein kinases MeSH D08.811.913.696.620.682.650 – phosphorylase kinase MeSH D08.811.913.696.620.682.700 – protein-serine-threonine kinases MeSH D08.811.913.696.620.682.700.062 – activin receptors MeSH D08.811.913.696.620.682.700.062.500 – activin receptors, type i MeSH D08.811.913.696.620.682.700.062.750 – activin receptors, type ii MeSH D08.811.913.696.620.682.700.109 – bone morphogenetic protein receptors MeSH D08.811.913.696.620.682.700.109.500 – bone morphogenetic protein receptors, type i MeSH D08.811.913.696.620.682.700.109.750 – bone morphogenetic protein receptors, type ii MeSH D08.811.913.696.620.682.700.125 – ca(2+)-calmodulin dependent protein kinase MeSH D08.811.913.696.620.682.700.125.500 – myosin-light-chain kinase MeSH D08.811.913.696.620.682.700.140 – casein kinases MeSH D08.811.913.696.620.682.700.140.300 – casein kinase i MeSH D08.811.913.696.620.682.700.140.300.100 – casein kinase ialpha MeSH D08.811.913.696.620.682.700.140.300.200 – casein kinase idelta MeSH D08.811.913.696.620.682.700.140.300.300 – casein kinase iepsilon MeSH D08.811.913.696.620.682.700.140.600 – casein kinase ii MeSH D08.811.913.696.620.682.700.150 – cyclic nucleotide-regulated protein kinases MeSH D08.811.913.696.620.682.700.150.125 – cyclic amp-dependent protein kinases MeSH D08.811.913.696.620.682.700.150.125.500 – beta-adrenergic-receptor kinase MeSH D08.811.913.696.620.682.700.150.150 – cyclic gmp-dependent protein kinases MeSH D08.811.913.696.620.682.700.150.575 – protamine kinase MeSH D08.811.913.696.620.682.700.200 – cyclin-dependent kinases MeSH D08.811.913.696.620.682.700.200.067 – cdc2-cdc28 kinases MeSH D08.811.913.696.620.682.700.200.067.249 – cdc2 protein kinase MeSH D08.811.913.696.620.682.700.200.067.500 – cdc28 protein kinase, s cerevisiae MeSH D08.811.913.696.620.682.700.200.067.875 – cyclin-dependent kinase 5 MeSH D08.811.913.696.620.682.700.200.067.900 – cyclin-dependent kinase 9 MeSH D08.811.913.696.620.682.700.200.323 – cyclin-dependent kinase 2 MeSH D08.811.913.696.620.682.700.200.451 – cyclin-dependent kinase 4 MeSH D08.811.913.696.620.682.700.200.515 – cyclin-dependent kinase 6 MeSH D08.811.913.696.620.682.700.200.580 – maturation-promoting factor MeSH D08.811.913.696.620.682.700.200.580.500 – cdc2 protein kinase MeSH D08.811.913.696.620.682.700.250 – dna-activated protein kinase MeSH D08.811.913.696.620.682.700.300 – eif-2 kinase MeSH D08.811.913.696.620.682.700.429 – glycogen synthase kinases MeSH D08.811.913.696.620.682.700.429.500 – glycogen synthase kinase 3 MeSH D08.811.913.696.620.682.700.494 – i-kappa B kinase MeSH D08.811.913.696.620.682.700.559 – map kinase kinase kinases MeSH D08.811.913.696.620.682.700.559.100 – map kinase kinase kinase 1 MeSH D08.811.913.696.620.682.700.559.200 – map kinase kinase kinase 2 MeSH D08.811.913.696.620.682.700.559.300 – map kinase kinase kinase 3 MeSH D08.811.913.696.620.682.700.559.400 – map kinase kinase kinase 4 MeSH D08.811.913.696.620.682.700.559.500 – map kinase kinase kinase 5 MeSH D08.811.913.696.620.682.700.559.800 – proto-oncogene proteins c-mos MeSH D08.811.913.696.620.682.700.559.842 – raf kinases MeSH D08.811.913.696.620.682.700.559.842.249 – oncogene proteins v-raf MeSH D08.811.913.696.620.682.700.559.842.374 – proto-oncogene proteins b-raf MeSH D08.811.913.696.620.682.700.559.842.500 – proto-oncogene proteins c-raf MeSH D08.811.913.696.620.682.700.565 – mitogen-activated protein kinase kinases MeSH D08.811.913.696.620.682.700.565.100 – map kinase kinase 1 MeSH D08.811.913.696.620.682.700.565.200 – map kinase kinase 2 MeSH D08.811.913.696.620.682.700.565.300 – map kinase kinase 3 MeSH D08.811.913.696.620.682.700.565.400 – map kinase kinase 4 MeSH D08.811.913.696.620.682.700.565.500 – map kinase kinase 5 MeSH D08.811.913.696.620.682.700.565.600 – map kinase kinase 6 MeSH D08.811.913.696.620.682.700.565.700 – map kinase kinase 7 MeSH D08.811.913.696.620.682.700.567 – mitogen-activated protein kinases MeSH D08.811.913.696.620.682.700.567.342 – extracellular signal-regulated map kinases MeSH D08.811.913.696.620.682.700.567.342.500 – mitogen-activated protein kinase 1 MeSH D08.811.913.696.620.682.700.567.342.750 – mitogen-activated protein kinase 3 MeSH D08.811.913.696.620.682.700.567.342.875 – mitogen-activated protein kinase 6 MeSH D08.811.913.696.620.682.700.567.342.937 – mitogen-activated protein kinase 7 MeSH D08.811.913.696.620.682.700.567.513 – jnk mitogen-activated protein kinases MeSH D08.811.913.696.620.682.700.567.513.500 – mitogen-activated protein kinase 8 MeSH D08.811.913.696.620.682.700.567.513.750 – mitogen-activated protein kinase 9 MeSH D08.811.913.696.620.682.700.567.513.800 – mitogen-activated protein kinase 10 MeSH D08.811.913.696.620.682.700.567.878 – p38 mitogen-activated protein kinases MeSH D08.811.913.696.620.682.700.586 – oncogene protein v-akt MeSH D08.811.913.696.620.682.700.606 – phytochrome a MeSH D08.811.913.696.620.682.700.646 – proline-directed protein kinases MeSH D08.811.913.696.620.682.700.646.500 – cyclin-dependent kinases MeSH D08.811.913.696.620.682.700.646.500.500 – cdc2-cdc28 kinases MeSH D08.811.913.696.620.682.700.646.500.500.500 – cyclin-dependent kinase 5 MeSH D08.811.913.696.620.682.700.646.500.750 – cyclin-dependent kinase 2 MeSH D08.811.913.696.620.682.700.646.500.875 – cyclin-dependent kinase 4 MeSH D08.811.913.696.620.682.700.646.500.937 – cyclin-dependent kinase 6 MeSH D08.811.913.696.620.682.700.646.625 – glycogen synthase kinase 3 MeSH D08.811.913.696.620.682.700.646.750 – mitogen-activated protein kinases MeSH D08.811.913.696.620.682.700.646.750.249 – extracellular signal-regulated map kinases MeSH D08.811.913.696.620.682.700.646.750.249.500 – mitogen-activated protein kinase 1 MeSH D08.811.913.696.620.682.700.646.750.249.750 – mitogen-activated protein kinase 3 MeSH D08.811.913.696.620.682.700.646.750.249.875 – mitogen-activated protein kinase 6 MeSH D08.811.913.696.620.682.700.646.750.249.937 – mitogen-activated protein kinase 7 MeSH D08.811.913.696.620.682.700.646.750.374 – jnk mitogen-activated protein kinases MeSH D08.811.913.696.620.682.700.646.750.374.500 – mitogen-activated protein kinase 8 MeSH D08.811.913.696.620.682.700.646.750.374.750 – mitogen-activated protein kinase 9 MeSH D08.811.913.696.620.682.700.646.750.374.800 – mitogen-activated protein kinase 10 MeSH D08.811.913.696.620.682.700.646.750.843 – p38 mitogen-activated protein kinases MeSH D08.811.913.696.620.682.700.725 – protein kinase C MeSH D08.811.913.696.620.682.700.725.100 – protein kinase C-alpha MeSH D08.811.913.696.620.682.700.725.400 – protein kinase C-delta MeSH D08.811.913.696.620.682.700.725.750 – protein kinase C-epsilon MeSH D08.811.913.696.620.682.700.755 – proto-oncogene proteins C-akt MeSH D08.811.913.696.620.682.700.759 – proto-oncogene proteins C-bcr MeSH D08.811.913.696.620.682.700.776 – proto-oncogene proteins C-pim-1 MeSH D08.811.913.696.620.682.700.827 – rhodopsin kinase MeSH D08.811.913.696.620.682.700.862 – ribosomal protein s6 kinases MeSH D08.811.913.696.620.682.700.862.249 – ribosomal protein s6 kinases, 70-kda MeSH D08.811.913.696.620.682.700.862.500 – ribosomal protein s6 kinases, 90-kda MeSH D08.811.913.696.620.682.725 – protein-tyrosine kinase MeSH D08.811.913.696.620.682.725.049 – focal adhesion protein-tyrosine kinases MeSH D08.811.913.696.620.682.725.049.500 – focal adhesion kinase 1 MeSH D08.811.913.696.620.682.725.049.750 – focal adhesion kinase 2 MeSH D08.811.913.696.620.682.725.200 – mitogen-activated protein kinase kinases MeSH D08.811.913.696.620.682.725.200.100 – map kinase kinase 1 MeSH D08.811.913.696.620.682.725.200.200 – map kinase kinase 2 MeSH D08.811.913.696.620.682.725.200.300 – map kinase kinase 3 MeSH D08.811.913.696.620.682.725.200.400 – map kinase kinase 4 MeSH D08.811.913.696.620.682.725.200.500 – map kinase kinase 5 MeSH D08.811.913.696.620.682.725.200.600 – map kinase kinase 6 MeSH D08.811.913.696.620.682.725.200.700 – map kinase kinase 7 MeSH D08.811.913.696.620.682.725.300 – proto-oncogene proteins c-fes MeSH D08.811.913.696.620.682.725.400 – receptor protein-tyrosine kinases MeSH D08.811.913.696.620.682.725.400.020 – fms-like tyrosine kinase 3 MeSH D08.811.913.696.620.682.725.400.024 – receptor, fibroblast growth factor, type 1 MeSH D08.811.913.696.620.682.725.400.037 – receptor, fibroblast growth factor, type 2 MeSH D08.811.913.696.620.682.725.400.043 – receptor, fibroblast growth factor, type 3 MeSH D08.811.913.696.620.682.725.400.046 – receptor, fibroblast growth factor, type 4 MeSH D08.811.913.696.620.682.725.400.050 – proto-oncogene proteins c-kit MeSH D08.811.913.696.620.682.725.400.075 – proto-oncogene proteins c-met MeSH D08.811.913.696.620.682.725.400.087 – proto-oncogene proteins c-ret MeSH D08.811.913.696.620.682.725.400.100 – receptor, epidermal growth factor MeSH D08.811.913.696.620.682.725.400.150 – receptor, erbb-2 MeSH D08.811.913.696.620.682.725.400.175 – receptor, erbb-3 MeSH D08.811.913.696.620.682.725.400.185 – receptor, igf type 1 MeSH D08.811.913.696.620.682.725.400.200 – receptor, insulin MeSH D08.811.913.696.620.682.725.400.500 – receptor, macrophage colony-stimulating factor MeSH D08.811.913.696.620.682.725.400.660 – receptor, trka MeSH D08.811.913.696.620.682.725.400.700 – receptor, trkb MeSH D08.811.913.696.620.682.725.400.800 – receptor, trkc MeSH D08.811.913.696.620.682.725.400.850 – receptors, eph family MeSH D08.811.913.696.620.682.725.400.850.050 – receptor, epha1 MeSH D08.811.913.696.620.682.725.400.850.100 – receptor, epha2 MeSH D08.811.913.696.620.682.725.400.850.150 – receptor, epha3 MeSH D08.811.913.696.620.682.725.400.850.200 – receptor, epha4 MeSH D08.811.913.696.620.682.725.400.850.250 – receptor, epha5 MeSH D08.811.913.696.620.682.725.400.850.300 – receptor, epha6 MeSH D08.811.913.696.620.682.725.400.850.400 – receptor, epha7 MeSH D08.811.913.696.620.682.725.400.850.500 – receptor, epha8 MeSH D08.811.913.696.620.682.725.400.850.600 – receptor, ephb1 MeSH D08.811.913.696.620.682.725.400.850.650 – receptor, ephb2 MeSH D08.811.913.696.620.682.725.400.850.700 – receptor, ephb3 MeSH D08.811.913.696.620.682.725.400.850.750 – receptor, ephb4 MeSH D08.811.913.696.620.682.725.400.850.800 – receptor, ephb5 MeSH D08.811.913.696.620.682.725.400.900 – receptors, platelet-derived growth factor MeSH D08.811.913.696.620.682.725.400.900.500 – receptor, platelet-derived growth factor alpha MeSH D08.811.913.696.620.682.725.400.900.750 – receptor, platelet-derived growth factor beta MeSH D08.811.913.696.620.682.725.400.925 – receptors, tie MeSH D08.811.913.696.620.682.725.400.925.249 – receptor, tie-1 MeSH D08.811.913.696.620.682.725.400.925.500 – receptor, tie-2 MeSH D08.811.913.696.620.682.725.400.950 – receptors, vascular endothelial growth factor MeSH D08.811.913.696.620.682.725.400.950.100 – vascular endothelial growth factor receptor-1 MeSH D08.811.913.696.620.682.725.400.950.200 – vascular endothelial growth factor receptor 2 MeSH D08.811.913.696.620.682.725.400.950.300 – vascular endothelial growth factor receptor-3 MeSH D08.811.913.696.620.682.725.500 – proto-oncogene proteins c-abl MeSH D08.811.913.696.620.682.725.800 – src-family kinases MeSH D08.811.913.696.620.682.725.800.315 – lymphocyte specific protein tyrosine kinase p56(lck) MeSH D08.811.913.696.620.682.725.800.472 – oncogene protein pp60(v-src) MeSH D08.811.913.696.620.682.725.800.551 – proto-oncogene proteins c-fyn MeSH D08.811.913.696.620.682.725.800.590 – proto-oncogene proteins c-hck MeSH D08.811.913.696.620.682.725.800.610 – proto-oncogene proteins c-yes MeSH D08.811.913.696.620.682.725.800.630 – proto-oncogene proteins pp60(c-src) MeSH D08.811.913.696.620.682.725.900 – zap-70 protein-tyrosine kinase MeSH D08.811.913.696.620.685 – pyridoxal kinase MeSH D08.811.913.696.620.695 – pyruvate kinase MeSH D08.811.913.696.620.750 – thymidine kinase MeSH D08.811.913.696.620.800 – uridine kinase MeSH D08.811.913.696.630 – phosphotransferases (carboxyl group acceptor) MeSH D08.811.913.696.630.025 – acetate kinase MeSH D08.811.913.696.630.050 – aspartate kinase MeSH D08.811.913.696.630.050.050 – aspartokinase homoserine dehydrogenase MeSH D08.811.913.696.630.700 – phosphoglycerate kinase MeSH D08.811.913.696.640 – phosphotransferases (nitrogenous group acceptor) MeSH D08.811.913.696.640.025 – arginine kinase MeSH D08.811.913.696.640.150 – creatine kinase MeSH D08.811.913.696.640.150.500 – creatine kinase, bb form MeSH D08.811.913.696.640.150.625 – creatine kinase, mb form MeSH D08.811.913.696.640.150.750 – creatine kinase, mitochondrial form MeSH D08.811.913.696.640.150.875 – creatine kinase, mm form MeSH D08.811.913.696.645 – phosphotransferases (paired acceptors) MeSH D08.811.913.696.645.700 – pyruvate, orthophosphate dikinase MeSH D08.811.913.696.650 – phosphotransferases (phosphate group acceptor) MeSH D08.811.913.696.650.025 – adenylate kinase MeSH D08.811.913.696.650.150 – atp synthetase complexes MeSH D08.811.913.696.650.150.500 – proton-translocating atpases MeSH D08.811.913.696.650.150.500.249 – bacterial proton-translocating atpases MeSH D08.811.913.696.650.150.500.500 – chloroplast proton-translocating atpases MeSH D08.811.913.696.650.150.500.750 – mitochondrial proton-translocating atpases MeSH D08.811.913.696.650.150.500.875 – vacuolar proton-translocating atpases MeSH D08.811.913.696.650.450 – guanylate kinase MeSH D08.811.913.696.650.550 – nucleoside-diphosphate kinase MeSH D08.811.913.696.650.575 – nucleoside-phosphate kinase MeSH D08.811.913.696.900 – transferases (other substituted phosphate groups) MeSH D08.811.913.696.900.074 – CDP-diacylglycerol—inositol 3-phosphatidyltransferase MeSH D08.811.913.696.900.150 – CDP-diacylglycerol—serine O-phosphatidyltransferase MeSH D08.811.913.696.900.200 – diacylglycerol cholinephosphotransferase MeSH D08.811.913.696.900.250 – ethanolaminephosphotransferase
Because of this fact, it has become common practice to establish the quality of NMR ensembles, by comparing it against the unique conformation determined by X-ray diffraction, for the same protein. However, the X-ray diffraction structure may not exist, and, since the proteins in solution are flexible molecules, a protein represented by a single structure may lead to underestimate the intrinsic variation of the atomic positions of a protein. A set of conformations, determined by NMR or X-ray crystallography may be a better representation of the experimental data of a protein than a unique conformation. The utility of a model will be given, at least in part, by the degree of accuracy and precision of the model. An accurate model with relatively poor precision could be useful to study the evolutionary relationships between the structures of a set of proteins, whereas the rational drug design requires both precise and accurate models. A model that is not accurate, regardless of the degree of precision with which it was obtained will not be very useful. Since protein structures are experimental models that can contain errors, it is very important to be able to detect these errors. The process aimed at the detection of errors is known as validation. There are several methods to validate structures, some are statistical like PROCHECK and WHAT IF while others are based on physical principles as CheShift, or a mixture of statistical and physics principles PSVS.
The low energy consumption, low maintenance and small size of LEDs has led to uses as status indicators and displays on a variety of equipment and installations. Large-area LED displays are used as stadium displays, dynamic decorative displays, and dynamic message signs on freeways. Thin, lightweight message displays are used at airports and railway stations, and as destination displays for trains, buses, trams, and ferries.
==== Knight/Dame Grand Cross of the Order of the British Empire (GBE) ==== Civil The Right Honourable Dame Margaret Mary Beckett, , Member of Parliament for Derby South. For Parliamentary, Political and Public Service. Professor Dame Carol Mary Black, , Independent Adviser on Combatting Drugs. For Public Service. Sir William Blackledge Beaumont, , Chair, World Rugby. For services to Rugby Union Football and to Charity. Professor Sir James Rufus McDonald, , President, Royal Academy of Engineering. For services to Engineering, to Education and to Energy. Sir Ridley Scott, Director and Producer. For services to the UK Film Industry.
Sources: en.wikipedia.org
== Confounders and Diagnostic Limitations == Several Systemic and age-related factors can severely limit the accuracy of skin turgor as a standalone diagnostic tool. In patients with hypernatremic dehydration, where sodium levels in the blood are abnormally high, water is pulled from the cells into the extracellular spaces, which keeps the skin feeling doughy rather than producing traditional tenting. Conversely, senior citizens naturally experience a sharp decline in dermal collagen synthesis and elastic fibers as they age. This natural loss of skin elasticity causes healthy, well-hydrated older adults to demonstrate prolonged tenting that can mistakenly be read as dehydration.
== Social disparities in glaucoma care and research == A study conducted in the UK showed that people living in an area of high deprivation were likely to be diagnosed in the later stage of the disease. It also showed that there was a lack of professional ophthalmic services in the area of high deprivation. A study in 2017 shows that there is a huge difference in the volume of glaucoma testing depending on the type of insurance in the US. Researchers reviewed 21,766 persons aged ≥ 40 years old with newly diagnosed open-angle glaucoma (OAG) and found that Medicaid recipients had substantially lower volume of glaucoma testing performed compared to patients with commercial health insurance. Results from a meta-analysis of 33,428 primary open-angle glaucoma (POAG) participants published in 2021 suggest that there are substantial ethnic and racial disparities in clinical trials in the US. Although ethnic and racial minorities have a higher disease burden, the 70.7% of the study participants was White as opposed to 16.8% Black and 3.4% Hispanic/Latino.
== History == The discovery of phosphocreatine was reported by Grace and Philip Eggleton of the University of Cambridge and separately by Cyrus Fiske and Yellapragada Subbarow of the Harvard Medical School in 1927. A few years later David Nachmansohn, working under Meyerhof at the Kaiser Wilhelm Institute in Dahlem, Berlin, contributed to the understanding of the phosphocreatine's role in the cell.
==== List of P-CABs in the markets (First year of approval for clinical use) ==== Revaprazan (2006) Vonoprazan (2014) Tegoprazan (2018) Fexuprazan (2021) Keverprazan (2023/China) Zastaprazan (2024/South Korea)
==== Underaged and pregnant offenders ==== Persons under the age of 18 at the time of their offence and pregnant women cannot be sentenced to death. Previously, offenders under 18 at the time of their offences would be indefinitely detained at the president's pleasure (TPP), with the normal period of detention having been between 10 and 20 years. These inmates would be released after receiving clemency from the President of Singapore, once they were assessed to be suitable for release. In 2010, the law was amended to allow judges to hand down a life imprisonment to offenders convicted of capital offences, but aged below 18 at the time of their crimes. They would be required to serve a minimum of 20 years before they can be reviewed for possible release. As for women who were pregnant at the time of their sentencing, they would automatically be sentenced to life imprisonment upon their conviction of any capital offences, though there have been no such cases as of yet. The first underaged offender to be sentenced to life imprisonment after the abolition of TPP was Myanmar national Zin Mar Nwe, a domestic worker who killed the mother-in-law of her employer in June 2018 at the age of 17. She received a life sentence in July 2023 after the High Court found her guilty of murder, with the trial judge Andre Maniam accepting that Zin was a minor and below 18 years of age when killing the 70-year-old victim and he thus opted to not impose a death sentence in her case.
Sources: en.wikipedia.org
It is not approved as a pharmaceutical in major markets and is used mainly as a cosmetic ingredient and a laboratory reagent. Regulatory status varies by country and by the product category in which it appears. Claims about therapeutic effects should be treated separately from permitted cosmetic labeling.
Reversed-phase high-performance liquid chromatography and mass spectrometry are common for the peptide portion. Copper content is usually determined by inductively coupled plasma techniques or by spectrophotometry. Ultraviolet-visible spectroscopy takes advantage of the visible absorption band of the copper complex.
Light, oxygen, and elevated temperature promote degradation of the peptide, and strongly acidic or alkaline conditions accelerate hydrolysis. The copper complex is generally more resistant to oxidation than the free peptide. Storage in a dry, dark, cold environment limits loss over time.
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.