SS-31 (Elamipretide): Mitochondria-Targeted Tetrapeptide

Most peptides have to find a receptor. SS-31 works differently: it is built to cross membranes freely and then bind the one lipid that lives almost exclusively in the inner mitochondrial membrane. That single design decision defines its research profile.

The molecule

SS-31 (elamipretide, C₃₂H₄₉N₉O₅, ≈ 640 g/mol) belongs to the Szeto-Schiller family of tetrapeptides. Its alternating aromatic–cationic amino acid sequence (D-Arg-Dmt-Lys-Phe-NH₂) allows it to penetrate cell and mitochondrial membranes without requiring a transport protein. Once inside, it binds cardiolipin, the phospholipid that anchors electron-transport-chain complexes and cytochrome c to the inner membrane.

Why it’s studied

Binding cardiolipin is not just localization — it is mechanistically relevant:

• Mitochondrial bioenergetics — cardiolipin organizes respiratory supercomplexes; SS-31 research examines whether binding preserves complex function under stress
• ROS and oxidative-stress models — the cardiolipin–cytochrome c interaction is a node in electron-transport efficiency and reactive oxygen production
• Ischemia-reperfusion injury — where mitochondrial permeability transition during reperfusion is a central event
• Age-related mitochondrial decline — a recurring theme given cardiolipin content drops in aging tissue

Szeto’s 2006 review in The AAPS Journal is a standard entry point for the family’s mechanism.

Handling notes

Lyophilized, reconstitute with bacteriostatic water; the reconstitution calculator does the math. Store at −20°C lyophilized.

See SS-31 for CAS, purity and full specifications.

For laboratory research use only. Not medical advice.