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BlueNex Labs

Glossary · 2026-09-24

Scientific lead: Alice Kay, Ph.D.

Cyclic peptide, laboratory definition

A cyclic peptide has its backbone, or a side-chain bridge, closed into a ring. One common ring is a disulfide bridge between cysteines. Another is a head-to-tail bond between the N-terminus and the C-terminus. The ring changes the mass relative to the open chain, so the species on the report has to say which form was calculated.

This catalogue does not assign a ring from a product title. The BPC-157 string published here has no cysteine and is filed as a linear sequence on the linear peptide term. Structural context is in structural peptides. Research use only.

Published lot files for this catalogue are indexed in the certificates library. This definition does not add a report, and it does not assign a task identifier. Research use only.

Frequently asked questions

Is every catalogue peptide cyclic?
No. Read the sequence and the mass species. A title does not establish a ring.
Does a disulfide always mean the peptide is cyclic?
A disulfide can close one chain or connect two chains. The report's species line is what you file, not a guess from the word.

Research use only. BlueNex Labs does not provide medical or veterinary advice. Confirm your institution’s policies before purchase. How a comparison or class note is checked sits on documentation standards. The biochemist of record is Alice Kay, Ph.D.