Peptide T

1 Identity

Linear synthetic octapeptide, all-L in the parent form. An eight-residue fragment corresponding to a region of the HIV-1 gp120 envelope protein. DAPTA, the D-Ala1 analog, is a related article and not a synonym.

Sequence

H-Ala-Ser-Thr-Thr-Thr-Asn-Tyr-Thr-OH (ASTTTNYT). Named for its threonine content — five of eight residues are Thr or Ser.

Molecular formula

C35H55N9O16

Average mass

857.872 Da average, from the formula C35H55N9O16.

Monoisotopic mass

857.37668 Da monoisotopic neutral; [M+H]+ 858.38396.

Salt / variant note

DAPTA, the D-Ala1 analog — identical formula and identical mass, distinguishable only by chiral analysis. The same class of problem is recorded against Dermorphin and against Melanotan I under Alpha-MSH. Also the many Thr-rich permutations at the same composition: with five Thr/Ser residues in eight positions the sequence has an unusually large number of same-mass permutations, and MS/MS assignment is not optional.

2 Class & testing panel

Form

Single article

Testing panel

P1 — panel definition

3 Primary sources & evidence

The index reports the design and provenance of the literature, not a conclusion about effect.

Identity is settled. The formula is taken from PubChem CID 73352 and both masses agree with it. The clinical literature is historical and is not reproduced or adopted.

4 Storage & specification

Storage

Lyophilized powder, -20 degrees C plus or minus 5 degrees C, desiccated. The Asn residue is a deamidation liability and the Thr-rich backbone is hydrolytically sensitive; not to be stored in solution.

Shelf life

Not assigned. Provisional dating is not defensible for this article without measured stability data, given the deamidation and hydrolysis liabilities. That measured data is the condition on which sale opens.