Researchers at the University of Utah found a tiny protein called PapB. This enzyme can tie the ends of therapeutic peptides together, turning them into small rings. The ring shape makes the medicines work better inside the body.
The finding is exciting for drugs like semaglutide, the active ingredient in Ozempic and Wegovy. Those medicines treat diabetes and obesity. Changing them into ring forms could make them last longer and act stronger.
Why Ring‑Shaped Peptides Help Drugs
Peptides are hard to handle because they have many reactive spots. That reactivity is useful in biology, but it makes precise changes difficult. The scientists showed that PapB works like a tiny machine, adding very specific modifications to peptides. They say this could lead to the next generation of peptide medicines.
Eastman and his mentor, Professor Vahe Bandarian, started a company called Sethera to move the discovery toward real products. Their work earned them the 2025 Founders of the Year award from the university.
A Simpler Way Than Old Chemistry
Usually, making a peptide into a ring needs complicated and expensive chemistry, especially late in drug development. PapB offers a cleaner method. It creates a precise bond that joins the peptide ends without extra “leader” sequences that enzymes normally need.
The team published their results in the journal ACS Bio & Med Chem Au. They used PapB, a radical SAM enzyme, to link the ends of GLP‑1‑like peptides. The bond formed is a sulfur‑carbon thioether. Experiments showed that PapB could build these rings even when the peptides contained unusual building blocks often used in modern drugs.
The Enzyme Works With Complex Drugs
Earlier work from the same lab introduced the idea of enzyme‑made rings. This new study proved the concept works with real drug candidates. The researchers tested three different GLP‑1‑like peptides, and PapB turned each one from a straight chain into a ring. This shows the enzyme can act like a plug‑and‑play tool, even late in development.
Making Drugs Last Longer
Peptide drugs often break down quickly in the body. Proteases, which recycle proteins, cut peptides apart, shortening their effect. By tying the ends together, PapB hides the peptide from many of these proteases. The result is a longer half‑life and stronger therapeutic action.
Big Potential for Future GLP‑1 Medicines
Traditional chemical methods can damage delicate peptide drugs, and many enzymes need extra sequences to work. PapB works without those extra pieces, meaning it could be used for many different peptide medicines.
This flexibility may lead to new treatments that are more stable, more targeted, and easier to make. As one researcher put it, “We add a clean, late‑stage enzymatic step that can make existing drugs work even harder by installing a small, well‑defined ring.”