The amphibian antimicrobial peptide uperin 3.5 is a cross-α/cross-β chameleon functional amyloid.

Research Highlight

Shape-shifting peptide keeps infections at bay

© Kristian Bell/Moment/Getty Images

© Kristian Bell/Moment/Getty Images

An antimicrobial peptide found on the skin of an Australian toadlet alters shape in the presence of bacteria to help ward off infections.

The discovery of how the peptide, named uperin 3.5, undergoes this shape change could inform the development of new antibiotic drugs.

A team that included members of the Spanish National Research Council solved the three-dimensional molecular structure of uperin 3.5. This peptide is secreted by Mjoberg’s toadlet, a diminutive relative of toads that grows up to 2.5 centimetres in length and that lives in north-western Australia.

The researchers found when the peptide encounters a bacterial membrane, it changes from a helical form into tight, twisted fibrils. In so doing, it becomes toxic to intruding microbes. It may be possible to use similar strategies when developing artificial antimicrobial drugs.

Supported content

  1. PNAS 118, e2014442118 (2021). doi: 10.1073/pnas.2014442118
Institutions Share
Technion-Israel Institute of Technology (IIT), Israel 0.29
Ben-Gurion University of the Negev (BGU), Israel 0.25
Molecular Biology Institute of Barcelona (IBMB), CSIC, Spain 0.19
Migal - Galilee Research Institute, Israel 0.06
Tel-Hai College, Israel 0.06
Catalan Institution for Research and Advanced Studies (ICREA), Spain 0.06
Centre for Structural Systems Biology (CSSB), Germany 0.04
EMBL - Hamburg, Germany 0.04