Description
PrymaLab · Research Use Only
KPV 10mg
Lys-Pro-Val tripeptide · extended-supply vial · CAS 67727-97-3
KPV peptide 10mg is an extended-supply lyophilized vial of the Lys-Pro-Val tripeptide, CAS 67727-97-3, molecular weight 342.43. Ten milligrams corresponds to approximately 29.2 micromoles, twice the standard fill, intended for programmes running long enough that single-lot continuity becomes worth having.
Specification Table
| Property | Value |
|---|---|
| Compound | KPV |
| Vial content | 10 mg lyophilized powder |
| Molar content of vial | Approximately 29.2 µmol |
| Stock at 1 ml diluent | Approximately 29.2 mM |
| Stock at 2 ml diluent | Approximately 14.6 mM |
| Stock at 10 ml diluent | Approximately 2.9 mM |
| Systematic description | Lysine-proline-valine tripeptide |
| Alternative designation | α-MSH(11-13) |
| CAS number | 67727-97-3 |
| Molecular formula | C16H30N4O4 |
| Molecular weight | 342.43 g/mol |
| Amino acid sequence | Lys-Pro-Val |
| Residue count | 3 |
| Parent molecule | Alpha-melanocyte-stimulating hormone, residues 11 to 13 |
| Transport route | PepT1 (SLC15A1), the di- and tripeptide transporter |
| Reported downstream target | NF-κB signalling |
| Appearance | White lyophilized cake |
| Purity | Per lot-specific certificate of analysis |
| Solubility | Water soluble. Compatible with bacteriostatic and sterile water |
| Storage, lyophilized | -20°C, protected from light and moisture |
| Storage, reconstituted | 2-8°C, protected from light |
| Regulatory status | No approved human or veterinary formulation in any jurisdiction |
What Is NF-κB and Why Is It the Target?
NF-κB is a transcription factor family that sits at the centre of inflammatory gene regulation, and understanding its normal behaviour explains what a suppressor is doing.
In an unstimulated cell, NF-κB dimers are held in the cytoplasm bound to inhibitory IκB proteins. An inflammatory signal triggers phosphorylation of IκB, which marks it for degradation. Released NF-κB translocates to the nucleus and drives transcription of a large set of genes: cytokines, chemokines, adhesion molecules and further components of the inflammatory programme.
A compound reducing NF-κB activation is therefore acting upstream of a broad transcriptional response rather than on any single mediator. That breadth is both the appeal and the interpretive difficulty, since a change in any one downstream readout could reflect the pathway rather than a specific interaction.
The luciferase reporter assay used in the primary KPV work measures exactly this step. A construct carrying NF-κB binding sites upstream of luciferase reports transcriptional activity directly, which is why it appears throughout this literature.
When Does KPV Peptide 10mg Earn Its Place?
For KPV peptide 10mg, lot continuity is the substantive argument, and for a tripeptide it carries less weight than for a longer sequence, which is worth being honest about.
Peptide synthesis lots vary in purity profile, residual solvent, counterion content and the distribution of deletion sequences. For a 43-residue peptide those variations are substantial, because coupling efficiency compounds across many steps. For a three-residue peptide, synthesis is short enough that lot-to-lot variation is comparatively small.
That said, counterion content still varies, and it affects the mass-to-mole conversion. A trifluoroacetate salt and an acetate salt of the same peptide contain different amounts of actual peptide per weighed milligram. Where a study compares across lots without checking counterion, that difference propagates silently.
The other argument is simply throughput. Work consuming material steadily across months advantages from fewer purchasing rounds and fewer opportunities to introduce a new variable.
How Should 10mg Be Divided and Stored?
With KPV peptide 10mg, reconstitute once and aliquot immediately, freeze the aliquots and thaw each once. That order matters more than the specific volumes.
KPV tolerates freeze-thaw better than most peptides, because it has no disulfides to scramble, no oxidation-prone residues and minimal secondary structure to lose. That makes aliquoting less critical here than for thymosin β4 or a growth factor, though it remains good practice.
Aliquot volume should match single-experiment consumption. Ten milligrams into 2 ml gives approximately 14.6 mM, matching what a 5mg vial in 1 ml produces, which keeps dilution arithmetic consistent between the two formats and is worth doing purely for that reason.
Adsorptive loss is the more relevant concern at working concentration. A small basic peptide binds to container surfaces, and the proportion lost rises as concentration falls. Low-binding consumables address it, and a carrier protein helps where the assay permits.
What Analytical Confirmation Is Appropriate?
For a tripeptide the analytical burden is light compared with the longer peptides in this catalogue, and that is worth knowing so effort goes where it matters.
Mass spectrometry confirms molecular weight at 342.43 and, for a three-residue sequence, essentially confirms identity at the same time. There are few plausible impurities that would share that exact mass.
Reversed-phase chromatography establishes purity, and for a short peptide the chromatogram is usually clean, with impurities well resolved rather than co-eluting as they do with longer sequences.
Counterion identity is the value most often absent from certificates and most worth requesting for this compound. Trifluoroacetate is common from synthesis and affects both the mass-to-mole conversion and, in some cell systems, the biology itself, since trifluoroacetate is not entirely inert at higher concentrations.
Water content by Karl Fischer titration matters for a hygroscopic lyophilized powder, since residual moisture inflates apparent mass.
What Is the PepT1 Expression Question?
Any experiment with this compound depends on a transporter, and whether that transporter is present is a question most designs leave unasked.
PepT1 expression is not uniform. It is constitutive in small intestinal epithelium, low or absent in healthy colon, and induced in colonic tissue during inflammation. Many commonly used cell lines express it poorly or not at all, and expression varies with culture conditions, passage number and confluence.
A negative finding in a system lacking PepT1 is therefore uninformative about the compound. It reports that the transporter was absent, not that the peptide is inactive, and the two are easy to conflate.
Measuring expression is straightforward. Quantitative PCR for SLC15A1 transcript, or immunoblot for the protein, establishes whether the transporter is present before the experiment rather than after an unexplained null.
A transport-competition control adds further confidence. Including an excess of a known PepT1 substrate should reduce KPV activity if uptake is transporter-dependent, and failure to see that reduction suggests something other than the published mechanism is operating.
How Should Aliquots Be Planned?
Ten milligrams divides into a lot of experiments, and planning the division before reconstituting avoids the common failure of thawing one aliquot repeatedly.
Start from what the work actually consumes. Estimate what a single experimental session uses at the intended working concentration, add a margin for repeats, and set aliquot volume from that rather than from what the available tubes suggest.
Vary the sizes where the work varies. A set of uniform aliquots suits uniform experiments, and most programmes are not uniform. A mix of larger and smaller divisions wastes less.
Label every tube with compound, concentration, lot and date. Frozen peptide aliquots are visually indistinguishable, and an unlabelled tube is functionally discarded.
For a tripeptide with good freeze-thaw tolerance the penalty for imperfect planning is modest, which is worth knowing so effort goes to the compounds where it matters more.
Reconstitution and Storage in Laboratory Practice
Ten milligrams into 2 ml gives approximately 14.6 mM. Into 10 ml it gives approximately 2.9 mM. Choose against the working range and record the choice before it becomes an assumption.
Add diluent gently down the vial wall and swirl until dissolved. Dissolution should be quick given water solubility, and a preparation that resists dissolving is worth questioning rather than agitating harder.
Keep the dry powder at -20°C in a sealed container away from light and moisture. Reconstituted solution at 2-8°C protected from light, aliquoted before freezing. Record lot, counterion where known, diluent, volume, concentration and date.
A Note on Counterion
For a compound this light, counterion content has a proportionally larger effect on peptide mass than it does for a heavier peptide, and it is worth understanding why.
Synthesis typically yields a trifluoroacetate salt. Trifluoroacetic acid has a formula weight of 114, against 342.43 for the peptide itself, so a mono-trifluoroacetate salt is roughly a quarter counterion by mass.
A weighed milligram of that salt therefore contains meaningfully less peptide than a milligram of the free base or an acetate salt would. For a 5 kDa peptide the same counterion represents a far smaller proportion.
Where a certificate does not state the counterion, molar calculations carry an unquantified error of that order. Requesting it costs nothing.
Published Literature
Checked against publisher records or primary indexes. The transporter review supplies the PepT1 background referenced throughout the sections above.
- Dalmasso G, Charrier-Hisamuddin L, Nguyen HT, Yan Y, Sitaraman S, Merlin D. Gastroenterology. 2008;134(1):166-178.
- Kannengiesser K, Maaser C, Heidemann J, et al. Inflammatory Bowel Diseases. 2008;14(3):324-331. DOI: 10.1002/ibd.20334
- Brzoska T, Luger TA, Maaser C, Abels C, Böhm M. Endocrine Reviews. 2008;29(5):581-602.
- Getting SJ, Perretti M. Trends in Pharmacological Sciences. 2000;21(9):327-329.
- Daniel H. Annual Review of Physiology. 2004;66:361-384.
Frequently Asked Questions
What is KPV peptide 10mg?
An extended-supply lyophilized vial of the Lys-Pro-Val tripeptide, CAS 67727-97-3 at molecular weight 342.43, holding approximately 29.2 micromoles across ten milligrams. That is twice the standard fill. Laboratory research use only, and not approved for human or veterinary use.
What is NF-kappa-B?
A transcription factor family central to inflammatory gene regulation. Unstimulated cells hold it in the cytoplasm bound to inhibitory I-kappa-B proteins. Inflammatory signals trigger I-kappa-B degradation, freeing NF-kappa-B to enter the nucleus and drive transcription.
Why does suppressing it produce broad effects?
Because NF-kappa-B acts upstream of a large transcriptional programme rather than on any single mediator, so reducing its activation shifts many downstream readouts at once. That breadth is the appeal. It is equally the interpretive difficulty, since one changed readout could reflect the whole pathway.
How is NF-kappa-B activity measured?
Most commonly by luciferase reporter assay, using a construct placing NF-kappa-B binding elements upstream of the luciferase gene so transcriptional activity reads out directly as luminescence. That method runs throughout this literature. It appears in the primary KPV characterisation work as the principal readout.
Does lot continuity matter as much for a tripeptide?
Less than for a longer sequence, which is worth being honest about. Coupling efficiency compounds across synthesis steps, so a 43-residue peptide accumulates far more variation than a three-residue one. Counterion content still varies and still matters.
What reconstitution volume keeps calculations consistent?
Two millilitres. That gives approximately 14.6 millimolar, the same stock concentration a 5mg vial reconstituted into 1 ml produces, so dilution calculations transfer between the two formats without any adjustment.
Does KPV tolerate freeze-thaw?
Better than most peptides do, and the reasons are structural rather than incidental. No disulfides exist to scramble, no oxidation-prone residues are present, and there is essentially no secondary structure to lose. Aliquoting remains sensible practice. It is simply less critical here.
What should a certificate of analysis include?
Mass confirmation, purity by chromatography, counterion identity and water content. Counterion is most often absent and most worth requesting, since trifluoroacetate from synthesis shifts the mass-to-mole conversion and is not entirely inert in some cell systems.
Why is analytical confirmation simpler for this compound?
Because three residues leaves few plausible impurities sharing the same mass, so mass spectrometry effectively confirms identity as well as weight. Chromatograms are usually clean too, with impurities well resolved rather than co-eluting as they do with longer sequences.
What is the main handling concern?
Adsorptive loss at low working concentrations. A small basic peptide binds to container surfaces, and the proportion lost rises as concentration falls because adsorption scales with surface area. Low-binding consumables address it, and a carrier protein helps where the assay allows.
Is PepT1 always present in a cell system?
No, and this is the assumption most worth checking. Expression is constitutive in small intestinal epithelium, low or absent in healthy colon, and induced during inflammation. Many common cell lines express it poorly, and expression varies with culture conditions, passage and confluence.
What does a negative finding mean without expression data?
Very little. It reports that the transporter may have been absent rather than that the peptide is inactive, and those are easy to conflate. Quantitative PCR for SLC15A1 or immunoblot for the protein resolves it before the experiment rather than after.
What control confirms transporter dependence?
A transport-competition arm. Including an excess of a known PepT1 substrate should reduce KPV activity if uptake is transporter-mediated. Failure to see that reduction suggests something other than the published mechanism is producing the observed effect.
How should aliquots be sized?
From what the work actually consumes rather than from the tubes to hand. Estimate single-session use at the intended working concentration, add a margin for repeats, and set volume accordingly. Vary the sizes where the programme varies, because uniform aliquots suit uniform experiments and most programmes are not.
Why label every tube?
Because frozen peptide aliquots are visually indistinguishable from one another. An unlabelled tube is functionally discarded, and for a vial divided into many portions the labelling is what preserves the value of buying the larger format in the first place.
Compliance Statement
KPV 10mg is sold exclusively for laboratory research use. It is not a drug, food, or cosmetic product, and it is not a dietary product of any kind. It is not approved by the FDA or any comparable authority for human or veterinary use. This product is not intended to diagnose, treat, cure, or prevent any disease. It must not be given to humans or animals. Purchase is restricted to qualified researchers and institutions operating within applicable laws. All handling is the responsibility of the purchasing laboratory.
Other formats of KPV
KPV is also stocked as KPV 10mg Nasal Spray, KPV 5mg/ml preloaded 3ml pen and KPV (5mg). Each listing states its own quantity and concentration, and the pen and vial comparison explains what changes between formats.
19 reviews for KPV (10mg)