Testagen Technical Overview
Testagen carries the molecular formula C₁₇H₂₉N₅O₉ and a molecular weight of 447.44 g/mol, and is indexed in PubChem as CID 123863700 under the title H-Lys-Glu-Asp-Gly-OH. Its four residues place it among the shortest peptides in the bioregulator literature, which is part of why it is used as a model compound in transport and binding work.
The Khavinson short peptide family was assembled from amino acid analysis of tissue-derived peptide complexes, with each sequence named after the tissue extract it was patterned on. Testagen corresponds to the anterior pituitary series and is studied alongside its structural neighbors Epitalon (Ala-Glu-Asp-Gly) and Pinealon (Glu-Asp-Arg), which differ from it by one residue.
Research interest in the sequence spans several laboratory disciplines. It appears in molecular modeling of amino acid and peptide transporters, in fluorescence work on peptide binding to labeled oligonucleotides, in cell culture studies of differentiation gene expression, and in surface chemistry as a candidate adsorption layer on metal substrates.
Compound Specifications
| Property |
Value |
| Compound Name |
Testagen |
| Compound Class |
Synthetic tetrapeptide (short peptide bioregulator) |
| Peptide Sequence (Three-Letter) |
H-Lys-Glu-Asp-Gly-OH |
| Peptide Sequence (One-Letter) |
KEDG |
| Sequence Length |
4 residues |
| CAS Number |
1026993-38-3 |
| PubChem CID |
123863700 |
| Molecular Formula |
C₁₇H₂₉N₅O₉ |
| Molecular Weight |
447.44 g/mol |
| Monoisotopic Mass |
447.1965 Da |
| InChIKey |
HKEYFJLTNCUNAD-DCAQKATOSA-N |
| Canonical SMILES |
C(CCN)CC(C(=O)NC(CCC(=O)O)C(=O)NC(CC(=O)O)C(=O)NCC(=O)O)N |
| Isomeric SMILES |
C(CCN)CC@@HN |
| IUPAC Name |
(4S)-5-[[(2S)-3-carboxy-1-(carboxymethylamino)-1-oxopropan-2-yl]amino]-4-[[(2S)-2,6-diaminohexanoyl]amino]-5-oxopentanoic acid |
| Synonyms |
KEDG, KEDG peptide, H-Lys-Glu-Asp-Gly-OH, Lys-Glu-Asp-Gly tetrapeptide |
| Source |
Synthetic, solid-phase peptide synthesis |
| Purity |
≥99% (HPLC) |
| Appearance |
Lyophilized white powder |
| Solubility |
Soluble in water |
| Storage |
-20°C, protect from light |
| Vial Size |
20mg |
Storage and Handling
- Store the lyophilized compound at -20°C in the sealed vial, protected from light and moisture.
- After reconstitution, store at 2°C to 8°C and use promptly. Avoid repeated freeze-thaw cycles.
- Maintain aseptic handling throughout reconstitution and aliquoting to preserve compound integrity.
- Allow the vial to reach room temperature before opening so condensation does not settle on the powder.
Lyophilized Format
This compound ships in lyophilized (freeze-dried) form. Freeze-drying supports long-term storage stability and preserves compound integrity. No fillers are added.
Research Use Disclaimer
Testagen is supplied for research use only. It is not a drug, food, cosmetic, or dietary supplement and has not been evaluated by the FDA. By purchasing, the buyer confirms the compound will be used solely for in vitro research.
Frequently Asked Questions
What Is Testagen?
Testagen is a synthetic tetrapeptide with the sequence Lys-Glu-Asp-Gly, one of the short peptide bioregulators described in the Khavinson literature. It is supplied as a research compound and is indexed in PubChem as CID 123863700.
What Is the Molecular Weight of Testagen?
Testagen has a molecular weight of 447.44 g/mol and a molecular formula of C₁₇H₂₉N₅O₉. Its monoisotopic mass of 447.1965 Da is the value used for LC-MS identity confirmation.
How Is Testagen Stored?
Testagen is stored at -20°C as a lyophilized powder in its sealed vial, protected from light. Once reconstituted, laboratories hold it at 2°C to 8°C and avoid repeated freeze-thaw cycles.
How Is the Purity of Testagen Verified?
Purity is confirmed by HPLC at ≥99%, with identity checked by mass spectrometry against the compound’s monoisotopic mass. Each lot of Testagen ships with a third-party certificate of analysis reporting both results.
What Research Areas Is Testagen Studied In?
Testagen appears in laboratory research on peptide transport across cell membranes, sequence-selective binding to DNA and deoxyribooligonucleotides, differentiation gene expression in cultured cells, and adsorption behavior at metal surfaces.
Testagen Research Areas
Fluorescence microscopy work using fluorescein-labeled short peptides recorded signal in the cytoplasm, nucleus, and nucleolus of the HeLa cell line after incubation with Testagen, Epitalon, and Pinealon, indicating that tetrapeptides of this size cross both the cell membrane and the nuclear envelope [1]. The same study measured Stern-Volmer fluorescence quenching constants for each peptide against labeled single- and double-stranded deoxyribooligonucleotides, and reported that Testagen bound preferentially to CAG-containing sequences [1].
Molecular modeling has since examined how peptides of this class reach the intracellular compartment. Docking of 26 ultrashort peptides against the ligand-binding sites of the LAT1, LAT2, and PEPT1 transporters returned higher binding scores for KEDG than for the bulk of di- and tripeptides screened, placing it among the sequences most compatible with these transport routes [2].
Reviews of the wider short peptide literature group KEDG with sequences reported to act on differentiation gene expression in cultured cells, and describe a shared mechanism in which short peptides interact with histones and DNA to alter the availability of specific genes for transcription [3].
Beyond cell systems, the sequence has been characterized in surface chemistry. An electrochemical and computational study of Testagen on copper in sodium chloride solution recorded roughly 86% corrosion inhibition efficiency, fitted the data to a Freundlich adsorption isotherm, and used DFT and Monte Carlo simulation to attribute the adsorption layer to a mix of electrostatic, van der Waals, and covalent interactions [4].
The oldest thread in the literature comes from animal model work carried out before the cell-level mechanism was described.
Tissue Morphology In Avian Model Studies
A series of studies in surgically hypophysectomized birds applied Lys-Glu-Asp-Gly and Ala-Glu-Asp-Gly and compared tissue outcomes against control model groups. Investigators measured thyroid-stimulating hormone and thyroid hormone concentrations and examined thyroid follicular structure by histology, reporting differences between peptide-exposed and control groups in both neonatally operated chickens [5] and mature and older birds [6]. A later paper from the same group applied the same comparison to thymus morphology and reported that the Lys-Glu-Asp-Gly group showed greater recovery of thymic structure than the Ala-Glu-Asp-Gly group [7].
| Research Area |
In Vitro Application |
| Peptide transport modeling |
Docking of KEDG against the LAT1, LAT2, and PEPT1 ligand-binding sites |
| Nucleic acid interaction |
Fluorescence quenching assays measuring KEDG binding to labeled deoxyribooligonucleotides and DNA |
| Subcellular localization |
Fluorescein-labeled peptide tracking across the cell membrane and nuclear envelope in cultured cell lines |
| Differentiation research |
Cell culture systems examining short peptide regulation of differentiation gene expression |
| Tissue histology |
Ex vivo sectioning and morphometry of thyroid and thymus tissue from avian pituitary-ablation models |
| Surface and materials chemistry |
Electrochemical, DFT, and Monte Carlo evaluation of KEDG adsorption on copper in saline media |
References
- Fedoreyeva LI, Kireev II, Khavinson VKh, Vanyushin BF (2011). Penetration of short fluorescence-labeled peptides into the nucleus in HeLa cells and in vitro specific interaction of the peptides with deoxyribooligonucleotides and DNA. Biochemistry (Moscow), 76(11), 1210-1219. https://doi.org/10.1134/S0006297911110022
- Khavinson VK, Linkova NS, Rudskoy AI, Petukhov MG (2023). Feasibility of Transport of 26 Biologically Active Ultrashort Peptides via LAT and PEPT Family Transporters. Biomolecules, 13(3), 552. https://pmc.ncbi.nlm.nih.gov/articles/PMC10046148/
- Khavinson V, Linkova N, Diatlova A, Trofimova S (2020). Peptide Regulation of Cell Differentiation. Stem Cell Reviews and Reports, 16(1), 118-125. https://doi.org/10.1007/s12015-019-09938-8
- Dobrițescu A, Samide A, Cioateră N, Mic OC, Ionescu C, Dăbuleanu I, Tigae C, Spînu CI, Oprea B (2025). The Inhibitory Effect and Adsorption Properties of Testagen Peptide on Copper Surfaces in Saline Environments: An Experimental and Computational Study. Molecules, 30(15), 3141. https://pmc.ncbi.nlm.nih.gov/articles/PMC12348504/
- Kuznik BI, Pateyuk AV, Rusaeva NS (2008). Effect of tetrapeptides Lys-Glu-Asp-Gly and Ala-Glu-Asp-Gly on the structure and function of the thyroid gland in neonatally hypophysectomized chickens. Bulletin of Experimental Biology and Medicine, 145(1), 104-107. https://doi.org/10.1007/s10517-008-0033-6
- Kuznik BI, Pateyuk AV, Rusaeva NS, Baranchugova LM, Obydenko VI (2011). Effects of peptides Lys-Glu-Asp-Gly and Ala-Glu-Asp-Gly on hormonal activity and structure of the thyroid gland in hypophysectomized young chickens and old hens. Bulletin of Experimental Biology and Medicine, 150(4), 495-499. https://doi.org/10.1007/s10517-011-1177-3
- Pateyk AV, Baranchugova LM, Rusaeva NS, Obydenko VI, Kuznik BI (2013). Effect of peptides Lys-Glu-Asp-Gly and Ala-Glu-Asp-Gly on the morphology of the thymus in hypophysectomized young and old birds. Bulletin of Experimental Biology and Medicine, 154(5), 681-685. https://doi.org/10.1007/s10517-013-2029-0
Certificate of Analysis (COA) for Every Batch
A Certificate of Analysis (COA) is a document that verifies a compound’s identity, purity, and batch quality through independent laboratory testing. Every compound from BioLongevity Labs ships with a COA tied to its specific batch, so researchers can confirm exactly what they received before it enters a protocol.
Each COA reports results from third-party laboratory analysis, including:
- Ultra-high-performance liquid chromatography with mass spectrometry (UHPLC-MS) for purity, typically confirmed at 99% or higher
- Mass identification for molecular confirmation and content quantitation
- Endotoxin quantitation by Limulus amebocyte lysate (LAL) assay where applicable
- Visual and physical characterization of the finished material
How to verify a COA independently
Every certificate can be checked against the issuing laboratory’s own records, not just the copy hosted here. Verification does not depend on BioLongevity Labs.
- MDx BioAnalytical Laboratory certificates carry a QC tracking number and a search code. Newer certificates also carry a QR code. Scan the code, or enter the search code at mdxbiolabs.com, to pull the official record.
- BioRegen reports of analysis carry a Report ID and a Validation Key. Scan the QR code on the certificate to open the official record, or reference both identifiers when contacting the laboratory at the address printed on the report.
- SafeCert Labs certificates, which appear on a number of earlier batches, carry a COA number and the signature of the reporting chemist. Reference that number when requesting confirmation from the laboratory directly.
Batches are frequently tested by both laboratories independently. When two certificates exist for the same lot, each one resolves at its own issuing laboratory, which lets a researcher confirm the same material twice through two unrelated sources.
COAs are sourced from independent certified labs rather than in-house testing alone, giving researchers a verifiable record of molecular integrity for each batch. All compounds are supplied for research use only.
Review the COAs for this batch below, or browse the full COA library.
Testagen(12099)
Testagen (260265)
Endotoxin Testagen
Testagen (251541)
Testagen (251541E)
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