Gut-hormone receptor lab probe (CHEMBL375360)
A short synthetic peptide that latches onto the gut-hormone receptor controlling gallbladder squeeze and pancreatic digestion, used only as a research tool, not a medicine.
A researcher, an agent, or an algorithm wrote down the sequence and picked a target to hit.
An AI model like OpenFold3 or AlphaFold built a 3D structure and scored how well it fits the binding site.
A second contributor repeated the computation on their own hardware and the scores matched.
A chemistry service or a researcher ordered the sequence, it was manufactured, and mass spectrometry confirmed the right molecule was produced.
A binding or activity measurement confirmed that it actually does what the computer predicted — or didn't.
What this is
This card describes a synthetic 7-amino-acid peptide (sequence DMGWMDF) catalogued in ChEMBL as CHEMBL375360, a research-grade ligand of the cholecystokinin-1 receptor (CCK-1R, gene symbol CCKAR). It is not a marketed drug, not a clinical candidate, and not a wellness peptide — it is a tool compound from a medicinal-chemistry program exploring short peptide ligands at the CCK receptor family.
What it does
The compound binds CCKAR with a reported IC50 of 28.18 nM (ChEMBL CHEMBL375360). CCKAR is the gastrointestinal and vagal cholecystokinin receptor — the same receptor that endogenous cholecystokinin (CCK) activates to trigger gallbladder contraction, pancreatic enzyme secretion, and meal-ending satiety signalling via vagal afferents to the brainstem. Receptor-binding affinity in this low-nanomolar range identifies the compound as a high-affinity CCKAR ligand in the in vitro assay context; the bioassay measures binding affinity only, not whether the ligand behaves as an agonist, antagonist, or partial agonist in cellular signalling. For background on CCKAR itself, see the related card on cholecystokinin (/card/pep-10311) if available.
Evidence
- Human: No human trials of this specific compound. CCK-1R agonists as a pharmacological class have been studied for obesity in multiple clinical programmes (dexloxiglumide and related compounds), none of which reached regulatory approval — short duration of action and tachyphylaxis at the receptor have been the recurrent limitations.
- In vitro: Binding affinity at CCKAR reported as IC50 = 28.18 nM in the ChEMBL bioassay record (CHEMBL375360). The peptide is documented in a medicinal-chemistry study of partial retro-inverso, retro, and inverso modifications of hydrazide-linked bifunctional peptides directed at opioid and cholecystokinin receptors (Lee et al., J. Med. Chem., 2007).
- Animal: No animal data attached to this specific 7-mer in the dossier.
Regulatory status
- US: Not an approved drug. Research-reagent status only. CCKAR is the target of the FDA-approved diagnostic agent sincalide (a synthetic sulfated CCK-8 analog used during cholescintigraphy), but this 7-mer is unrelated to that product line and has no approved human indication.
- EU / international: No approvals.
- WADA: Not specifically named.
Related peptides
- Cholecystokinin and CCK fragments — the endogenous ligand family for CCKAR.
- Other CCK-1R / CCK-2R research ligands catalogued in ChEMBL.
Research directions for this peptide, selected from the current sources — hypotheses you can explore and model. None of it is proven yet; tap any one to see the full thinking.
Could a peptide that activates the CCK-1 receptor counteract the constipation side effect of opioid pain medicines?
Constipation is one of the most debilitating and persistent side effects of opioid painkillers, affecting millions of chronic pain and cancer patients. A gut-targeted peptide that works by a completely different mechanism could help these patients without triggering opioid withdrawal or entering the brain.
Could a brief, pulse-like signal to the satiety receptor work better than a long-lasting one?
Previous drugs targeting this receptor stopped working because the body adapted to constant stimulation. A short-lived signal that mimics natural meal-triggered hormone pulses might reset that tolerance problem, offering a new approach to treating obesity.
Would forming a circular version of this peptide make it both more potent and harder for the body to break down?
Linear peptides are quickly destroyed in the bloodstream, which is why most peptide drugs need injections or frequent dosing. A cyclic version could survive long enough to be useful as a medicine, potentially as a pill-form satiety agent for obesity treatment.
Could this peptide preferentially hit the gut receptor and leave the brain receptor alone?
Drugs that only activate the gut form of the CCK receptor could reduce appetite without the anxiety, nausea, and neurological side effects that have hampered previous CCK-based obesity treatments.
Does the first amino acid of this peptide create a structural bend that helps the rest of it fit snugly into the receptor?
If a natural fold in the peptide explains its potency, chemists could lock that shape in permanently using a synthetic ring structure. Locked shapes often make much better drug candidates because they are harder for the body to break down.
▸full evidence table1 metrics
| metric | value | tool |
|---|---|---|
| IC50 | 28.18 nM | GPCRDB/ChEMBL |
▸structural qualityopenfold3
| metric | value | note |
|---|---|---|
| gpde | 0.981 | global PDE — lower = better |
| disorder | NaN | fraction disordered |
▸3-letter notation
▸recipeboltz-2 1.0
| parameter | value |
|---|---|
| model | boltz-2 1.0 |
| weights | — |
| hardware | nvidia_nim_api |
| mlx version | — |
| python | — |
| random seed | — |
| msa strategy | none |
| diffusion samples | 1 |
| runtime | — |
| predicted by | mlx@peptide |
| predicted at | 2026-04-24 |
▸citationbibtex
@peptide{pep10312,
sequence = {DMGWMDF},
target = {cckar},
author = {peptidemodel},
year = {2026},
status = {bioassayed}
}