SS-31

SS-31 is a designed tetrapeptide, not a fragment of a natural hormone. The sequence uses D-arginine, 2′,6′-dimethyltyrosine (Dmt), lysine and C-terminally amidated phenylalanine. The alternating aromatic and cationic residues are the design feature that later biophysical papers treat as the reason the peptide associates with membranes.

Development names accumulate faster than chemistry changes. Elamipretide is the International Nonproprietary Name. MTP-131 and Bendavia appear in older files. VaultLabs catalogs the research tetrapeptide as SS-31. A requisition citing any of those names should resolve to this lot family only after sequence and mass are confirmed — 639.79 g/mol, CAS 736992-21-5.

Dmt is a non-canonical residue. Generic peptide assumptions about tyrosine reactivity and about proteolytic stability do not transfer automatically. A method written for an all-L tetrapeptide is not a method written for this material.

Mitchell, Ng, Tamucci and colleagues reported in the Journal of Biological Chemistry (2020) that SS-31 binds lipid bilayers and modulates surface electrostatics, and they present that interaction as a component of the peptide's mechanism in model membranes. The work is biophysical, not a clinical outcome study.

Chavez, Tang, Campbell and colleagues mapped a mitochondrial protein-interaction landscape for SS-31 in Proceedings of the National Academy of Sciences (2020), using chemical crosslinking in mitochondria. That paper identifies protein neighbours of the peptide inside the organelle. It does not describe VaultLabs catalog material and it does not authorise human use.

A separate pharmaceutical development programme exists for elamipretide. Finished investigational or licensed products, where they exist, are not the lyophilised research vial. VaultLabs supplies the latter only.

HPLC release should resolve the amidated tetrapeptide from des-amido and deletion species. Because Dmt and D-arginine change both hydrophobicity and proteolytic behaviour, retention time will not match an all-L Tyr analogue if someone has used that as an informal standard. Mass confirmation at 639.79 g/mol is the identity check that does not depend on naming.

Store sealed lyophilised vials at 2–8 °C, protected from light and humidity, and equilibrate before opening. After reconstitution, keep freeze-thaw cycles logged. The aromatic Dmt residue is a reason to protect solutions from unnecessary light, as with other aromatic peptides.

Laboratories comparing mitochondrial peptides should not file SS-31 certificates under MOT-C or vice versa. MOT-C is a mitochondrial-encoded open-reading-frame peptide with a different mass and a different catalog identity.

SS-31 from VaultLabs is a research reference material for in vitro laboratory work. It is not a medicine, not a mitochondrial therapeutic, and not supplied for human or veterinary use. Development-name recognition does not change that classification.

The catalog SKU is a 10 mg lyophilised vial. Published certificates are retrieved through batch verification. Related mitochondrial research material on this site is documented separately as MOT-C.

This monograph is a laboratory reference article. It is not a protocol and not a substitute for institutional SOP review.

Cited papers explain membrane binding and mitochondrial protein contacts in experimental systems. They do not convert a research vial into a finished medicine. Query any mismatch between label, certificate and this page before the material is used.

Mitochondrial membrane-interaction assays

Cardiolipin and bilayer model systems

Non-canonical residue (Dmt) analytical methods

2–8 °C (lyophilized, sealed)

2–8 °C sealed lyophilized storage, protected from light and humidity.

Dmt and D-arginine make this a non-standard tetrapeptide. Protect from light once in solution; do not assume all-L tyrosine methods transfer.