SS-31

SS-31 in Canada is supplied by Horizon Peptides as a lyophilized powder in sealed research vials, stocked in 10 mg and 50 mg sizes with single-vial, 3-vial and 10-vial pack options. SS-31 is a synthetic tetrapeptide studied in mitochondrial membrane research.

SS-31 is four residues, D-Arg-Dmt-Lys-Phe-NH2, with a molecular weight of 639.8. Two features stand out in that short sequence: a D-form arginine, and Dmt, a modified tyrosine carrying two methyl groups. Neither appears in ordinary proteins.

The sequence belongs to a family designed around alternating charged and aromatic residues, an arrangement associated in the literature with affinity for cardiolipin, a phospholipid largely confined to the inner mitochondrial membrane.

That targeting is what distinguishes it from other short peptides. Rather than acting at a cell-surface receptor, it is studied for association with a specific membrane component, which places it in a different experimental category from most sequences stocked here.