[Gly11] Substance P is a full-length Substance P analog in which the native C-terminal Met11 residue is replaced by glycine.

This substitution removes the large hydrophobic methionine side chain almost completely while preserving the amidated peptide terminus. The analog is therefore useful for examining how C-terminal hydrophobic bulk contributes to the Substance P scaffold.

Product Information

Removing the Native Met11 Side Chain

Met11 contributes a relatively large hydrophobic side chain to the C-terminal region of native Substance P. Gly has only a hydrogen atom as its side chain and provides much greater local conformational freedom.

The Met11 → Gly substitution therefore changes both side-chain hydrophobicity and backbone flexibility at the peptide terminus.

We recommend using this analog primarily for direct SAR comparisons rather than assuming that it reproduces native NK1 potency. A large change at the terminal residue can alter receptor recognition even though the first ten residues remain unchanged.

Research Applications

[Gly11] Substance P can support C-terminal Substance P SAR, tachykinin receptor studies, residue-scanning experiments and comparisons of hydrophobic versus minimal C-terminal side chains.

The absence of methionine also eliminates Met11 oxidation as a source of peptide heterogeneity.

Frequently Asked Questions

What is modified in [Gly11] Substance P?

Met11 is replaced by Gly.

Why is Gly11 useful for SAR studies?

Gly removes most of the side-chain bulk present at native Met11 and increases local backbone flexibility, providing a strong test of the importance of the C-terminal hydrophobic residue.

Does [Gly11] Substance P contain methionine?

No. Met11 is completely replaced by glycine.

Research Use Only.