The past week brought three new peptide studies worth a closer look. Two of them tackle one of the biggest problems in medicine right now: bacteria that no longer respond to our antibiotics. The third looks at a well known bone peptide and asks whether it can be made to last longer in the body.
A longer lasting version of teriparatide
On 16 October, a team from Shandong University and the Shandong Academy of Pharmaceutical Sciences published work on teriparatide in the Journal of Medicinal Chemistry. Teriparatide is made from the first 34 amino acids of parathyroid hormone, but it breaks down quickly once it enters the body.
The researchers worked through the peptide one position at a time to find places where it could be safely changed, then attached fatty acid chains at serine and threonine sites. Of the 12 new versions they made, four kept activity close to the original. One of them, compound 62, held up far better in blood serum.
This is early preclinical work, but it shows how small chemical changes can make a peptide much more stable.
Deep learning designs new antimicrobial lipopeptides
On 17 October, researchers at Shanghai Jiao Tong University reported in Nature Communications that they had used a deep learning model to design lipopeptides, which are short peptides with a fatty acid tail.
They started with peptide sequences drawn from 96,911 bacterial genomes and narrowed thousands of candidates down to 289. They then made 46 of these in the lab, and 44 showed antimicrobial activity, a hit rate of almost 96%. That is unusually high for this kind of search.
Their lead compound, LP630, worked against a wide range of bacteria and gave strong results in mice with infected wounds. The work has not yet been tested in people.
A frog derived peptide against a resistant hospital germ
On 19 October, a group led from Houston Methodist Hospital published a study in Frontiers in Microbiology on CIT8, a 13 amino acid peptide. It is a shortened, machine learning optimised version of citropin 1.1, a natural peptide found on an Australian tree frog.
They tested CIT8 against Acinetobacter baumannii, a hospital germ that often resists carbapenem antibiotics and sits on the World Health Organization's critical priority list. CIT8 stopped 15 of 16 strains at 4 µg/mL, including resistant ones. At 20 µg/mL it reduced live bacteria to undetectable levels within 15 minutes, and it also helped the antibiotic meropenem work against resistant strains.
So far CIT8 has only been tested in the lab, and the authors describe further preclinical testing as the next step.
What it adds up to
Together, these studies show how quickly peptide science is moving, with computer design, natural compounds and careful chemistry all opening up new options. None of this work has reached human testing yet, so there is still a long road ahead. We will keep following each study as it develops.
All content on this page is for research and educational purposes only and is not medical advice.
For background on the bone peptide in the first study, see the Teriparatide Acetate research record.
For another antimicrobial peptide in the catalogue, see the LL-37 research record.