Bronchogen is the synthetic tetrapeptide Ala-Glu-Asp-Leu (AEDL), one of the short peptide bioregulators described by the Khavinson group in St Petersburg. With four residues and a molecular weight of 446 g/mol it belongs to the same structural family as Epithalon and Pinealon, and it is used in cell-based studies of sequence-specific DNA interaction and lung-lineage gene expression. NuVion supplies Bronchogen as a laboratory chemical for in vitro research use only.
Key facts
| Type | Synthetic tetrapeptide bioregulator |
| Amino acid count | 4 |
| Sequence | H-Ala-Glu-Asp-Leu-OH (AEDL) |
| Molecular formula | C19H32N4O8 |
| Molecular weight | 446.5 g/mol |
| Series | Khavinson short peptide bioregulators |
| Synonyms | AEDL, Ala-Glu-Asp-Leu, bronchogen tetrapeptide |
| Supplied form | Lyophilised powder in a sealed vial |
Bronchogen (AEDL)
$109 AUD
View productResearch use only. Not for human or veterinary use.
Structure and chemistry
Bronchogen is a linear tetrapeptide with a free N-terminal amine on alanine and a free C-terminal carboxyl on leucine. Two of the four residues carry acidic side chains, the glutamate gamma-carboxyl and the aspartate beta-carboxyl, so at neutral pH the molecule carries a net negative charge of two and dissolves freely in water. The leucine at position four supplies the only hydrophobic surface, which gives the sequence a distinct amphipathic character compared with the wholly polar Epithalon sequence Ala-Glu-Asp-Gly.
The Khavinson series is built on a shared design. Each member is a short peptide of two to four residues in which the side chains, not a folded backbone, carry the recognition information. Bronchogen differs from Epithalon at a single position, glycine replaced by leucine, and from Cardiogen at the same position, arginine replaced by leucine. That single substitution is what makes the set useful as a structure-activity series, because the peptides can be compared under identical assay conditions with only one variable changed.
Stability follows from the composition. There is no cysteine, methionine or tryptophan, so the peptide is not prone to oxidation and does not require light protection to the degree that indole-containing peptides do. The N-terminal alanine is not able to cyclise the way an N-terminal glutamate does, which removes the pyroglutamate route seen in Thymogen. The main degradation route in biological medium is aminopeptidase cleavage from the N-terminus, and the tetrapeptide is short-lived in serum-containing medium, which sets the practical exposure window in culture. Purity is determined by RP-HPLC and identity by mass spectrometry, with the parent ion at m/z 447.
Mechanism of action
No receptor has been identified for Bronchogen, and the mechanism is described at the level of the molecular interactions and cellular readouts that have been measured. The model proposed by the group that developed the series is that short acidic peptides of this kind enter the nucleus and bind double-stranded DNA at CNG sites, where the methylation state of the central cytosine alters the local geometry of the groove. Binding is proposed to displace or complement histone contacts at particular promoter regions, changing transcription of the genes downstream. Circular dichroism, molecular modelling and gel-shift work support sequence-preferential association with short DNA duplexes, and the model remains a hypothesis with no established pathway behind it.
The measured readouts in cell systems are transcriptional. In bronchial epithelial and fibroblast cultures, exposure to AEDL has been reported to change transcript and protein levels of lineage markers associated with airway epithelium, including surfactant-associated proteins and the transcription factors that regulate them. The reported effects are measured by qPCR, immunocytochemistry and Western blot over a window of hours to days, and they are read as changes in differentiation marker expression in culture. Because the peptide is degraded quickly by aminopeptidases, work in serum-containing medium typically uses repeated exposure or serum-reduced conditions to hold the parent compound present long enough to register a transcriptional change.
Research applications
- Sequence-specific DNA interaction studies: circular dichroism, thermal denaturation and electrophoretic mobility shift assays with short synthetic duplexes containing CNG motifs.
- Gene expression profiling in bronchial epithelial and lung fibroblast cultures by qPCR or RNA-seq, following lineage and differentiation markers.
- Structure-activity comparison across the Khavinson tetrapeptide series, holding assay conditions constant while varying the residue at position four.
- Immunocytochemistry and Western blot for differentiation marker protein levels in primary and immortalised airway cell lines.
- Peptidase stability assays in serum and cell lysate, following loss of the parent tetrapeptide by LC-MS.
- Reference standard for RP-HPLC and LC-MS method development on short acidic peptides.
Bronchogen sits in NuVion’s Immune Signalling category alongside the other short peptide bioregulators.
Handling in the laboratory
Bronchogen is supplied lyophilised and is reconstituted with bacteriostatic water added slowly down the side of the vial and swirled until dissolved. The tetrapeptide is highly water-soluble and goes into solution without difficulty. The reconstitution calculator converts vial content and diluent volume into a stock concentration. Because the free acid form lowers the pH of unbuffered water, stock intended for cell work is diluted into buffered medium before use, and a vehicle control accounts for the benzyl alcohol carried over from the diluent.
Unopened vials are kept sealed, dry and refrigerated as stated on the product documentation. Reconstituted solution is refrigerated and used within the period given on that documentation, or aliquoted and frozen to avoid repeated freeze-thaw cycles. Aliquoting matters more for short peptides than for larger sequences, because a tetrapeptide gives no spectroscopic handle for checking concentration after storage and the loss has to be measured by LC-MS instead.
Testing and supply from NuVion
NuVion’s Bronchogen is manufactured at a GMP-audited facility and independently tested by Janoshik Analytical, with purity determined by RP-HPLC and identity confirmed by mass spectrometry. The Certificate of Analysis for a tested batch is published on the product page and in the COA library. The peptide is supplied lyophilised in sealed vials and dispatched from within Australia.
Related compounds
Other short peptide bioregulators in the range include Epithalon (Ala-Glu-Asp-Gly), Cardiogen (Ala-Glu-Asp-Arg) and Pinealon (Glu-Asp-Arg), which differ from Bronchogen at a single position and are used as a comparison set.
Frequently asked questions
What is Bronchogen used for in research?
It is used as a defined tetrapeptide stimulus in cell-based studies of gene expression in airway epithelial and fibroblast cultures, in DNA-binding experiments with short synthetic duplexes, and as one member of a structure-activity series across the Khavinson short peptides.
How does Bronchogen differ from Epithalon?
The two sequences differ at position four. Epithalon is Ala-Glu-Asp-Gly and Bronchogen is Ala-Glu-Asp-Leu, so the substitution exchanges a glycine for a hydrophobic leucine while leaving the acidic core intact. That single change is what makes the pair useful for comparison under identical conditions.
Is Bronchogen a therapeutic good in Australia?
No. NuVion’s Bronchogen is a laboratory chemical for in vitro research. It is not included in the Australian Register of Therapeutic Goods, has not been assessed by the Therapeutic Goods Administration, and is not for human or veterinary use.
How should Bronchogen be stored?
Lyophilised vials are kept sealed, dry and refrigerated per the product documentation. Reconstituted solution is refrigerated and used within the stated period, or aliquoted and frozen to limit freeze-thaw cycles.
Research use only. This product is a laboratory chemical supplied for in vitro research. It is not included in the Australian Register of Therapeutic Goods and has not been assessed by the Therapeutic Goods Administration for quality, safety or efficacy. It is not for human or veterinary use, and nothing on this page is a representation about therapeutic use.
