2025-09-12 スイス連邦工科大学ローザンヌ校(EPFL)
Small amino acids (red) ‘screen’ attraction of proteins (yellow) to other molecules. 2025 SuNMIL EPFL CC BY SA
<関連情報>
- https://actu.epfl.ch/news/scientists-uncover-key-stabilizing-role-of-small-2/
- https://www.nature.com/articles/s41586-025-09506-w
タンパク質およびコロイド分散系に対するアミノ酸の安定化効果 Stabilizing effect of amino acids on protein and colloidal dispersions
Ting Mao,Xufeng Xu,Pamina M. Winkler,Cécilia Siri,Ekaterina Poliukhina,Paulo Jacob Silva,Nan Xu,Yu Hu,Karim Al Zahabi,Rémi La Polla,Zhi Luo,Quy Ong,Alfredo Alexander-Katz & Francesco Stellacci
Nature Published:10 September 2025
DOI:https://doi.org/10.1038/s41586-025-09506-w
Abstract
Amino acids (AAs) have a long history of being used as stabilizers for biological media1. For example, they are important components in biomedical formulations. The effect of AAs on biological systems is also starting to be appreciated. For example, it is believed that water-stressed cells increase the levels of AAs to prevent protein aggregation2. Several hypotheses have been put forward regarding their function, ranging from water-structuring3 to hydrotropic4 to specific effects such as stabilization against misfolding, yet it is not known whether their stabilizing function is protein specific or a generic colloidal property. Here we deduce that AAs possess a new and broad colloidal property: they stabilize patchy nanoscale colloids by adsorbing onto their surfaces through weak interactions. We demonstrate this general property by careful experimental evaluation of the stabilizing effect of AAs on dispersions of various proteins, plasmid DNA and non-biological nanoparticles. Furthermore, we develop a theoretical framework that captures this phenomenon and experimentally corroborate several new broad theoretical implications that apply beyond AAs. In vivo experiments further demonstrate that the addition of 1 M proline to insulin doubles its bioavailability in blood. Overall, our results indicate that the role of small molecules is as important as that of ionic strength and should always be reported in biophysics experiments.
