A Spinal Cord Enzyme Specifically Converts Dynorphin B to an Active Fragment
A novel endoprotease in bovine spinal cord specifically converts dynorphin B to leu-enkephalin-Arg6 (an active fragment) with high specificity (Km = 11 µM) — it does not act on other dynorphin forms.
Quick Facts
What This Study Found
A novel endoprotease with high specificity for dynorphin B (Km = 11 µM) was identified in bovine spinal cord. It does not act on other prodynorphin-derived peptides.
Key Numbers
How They Did This
Enzyme was purified 230-fold from bovine spinal cord extract using conventional chromatography. Characterized by SDS-PAGE, pH optimum, inhibitor profile, and substrate specificity.
Why This Research Matters
This enzyme provides a mechanism for selectively converting one opioid peptide into another. It could fine-tune opioid signaling by specifically controlling dynorphin B levels in the spinal cord.
The Bigger Picture
This enzyme converts a kappa-preferring peptide (dynorphin B) into a delta-preferring peptide (leu-enkephalin-Arg6). This represents a receptor-switching mechanism — the spinal cord can change which opioid receptor is activated by processing one peptide into another.
What This Study Doesn't Tell Us
In-vitro study using purified enzyme. The enzyme's role in living tissue and its regulation have not been studied. Only bovine spinal cord was examined.
Questions This Raises
- ?Could this enzyme be targeted to shift spinal pain control from kappa to delta signaling?
- ?Is this enzyme altered in chronic pain conditions?
Trust & Context
- Key Stat:
- Receptor-switching enzyme Converts kappa-preferring dynorphin B to delta-preferring leu-enkephalin-Arg6
- Evidence Grade:
- Preliminary in-vitro study — detailed enzyme characterization but unknown in-vivo significance.
- Study Age:
- Published in 1989 — discovered a novel peptide processing enzyme in the spinal cord.
- Original Title:
- A novel bovine spinal cord endoprotease with high specificity for dynorphin B.
- Published In:
- The Journal of biological chemistry, 264(19), 11082-6 (1989)
- Authors:
- Silberring, J(6), Nyberg, F(2)
- Database ID:
- RPEP-00135
Evidence Hierarchy
Frequently Asked Questions
Why would the body convert one opioid peptide into another?
Different opioid receptors produce different effects. By converting a kappa-active peptide into a delta-active one, the spinal cord can shift the type of pain modulation applied to incoming signals.
What is an endoprotease?
An enzyme that cuts proteins internally rather than from the ends. This one specifically recognizes and cuts dynorphin B at a particular internal site.
Read More on RethinkPeptides
Cite This Study
https://rethinkpeptides.com/research/RPEP-00135APA
Silberring, J; Nyberg, F. (1989). A novel bovine spinal cord endoprotease with high specificity for dynorphin B.. The Journal of biological chemistry, 264(19), 11082-6.
MLA
Silberring, J, et al. "A novel bovine spinal cord endoprotease with high specificity for dynorphin B.." The Journal of biological chemistry, 1989.
RethinkPeptides
RethinkPeptides Research Database. "A novel bovine spinal cord endoprotease with high specificit..." RPEP-00135. Retrieved from https://rethinkpeptides.com/research/silberring-1989-a-novel-bovine-spinal
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkPeptides research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.