2025-11-25 中国科学院(CAS)
The schematic shows that nFeS nanozymes with oxygenase- and isomerase-like activities modulate the microbial tryptophan pathway, generating a new indole derivative (I2CA). This enables the nanozymes to synergize with probiotics, killing pathogenic bacteria and improving gut health. (Image by GAO Lizeng’s group)
<関連情報>
- https://english.cas.cn/newsroom/research_news/life/202511/t20251127_1134059.shtml
- https://www.nature.com/articles/s41564-025-02176-4
ナノザイムはプロバイオティクスのトリプトファン代謝を調節し、哺乳類モデルにおけるサルモネラ菌感染を予防する Nanozymes modulate probiotic tryptophan metabolism to prevent Salmonella infection in mammalian models
Zishen Lin,Yue Feng,Lei Chen,Jinping Wang,Qian Wang,Haolin Cao,Yang Gao,Lixue Wang,Ying Zhang,Jing Jiang,Lizeng Gao & Bing Dong
Nature Microbiology Published:24 November 2025
DOI:https://doi.org/10.1038/s41564-025-02176-4
Abstract
Probiotics are promising alternatives to antibiotics for the treatment of intestinal infections, but the effects of probiotics alone are often insufficient. Here we uncovered synergism between antibacterial iron–sulfur nanozymes (nFeS) and tryptophan derivatives that protects mice and pigs against bacterial gut infections. nFeS selectively inhibited potential intestinal pathogens while sparing commensal Lactobacillus vaginalis, whose presence enhanced the protective activity of nFeS against Salmonella enterica subsp. enterica serovar Typhimurium in vivo. Metabolomics and mutational analysis revealed that L. vaginalis synthesized 2-indolecarboxylic acid from a tryptophan derivative, indole-3-carboxaldehyde, a reaction that was catalysed by nFeS. The cytoplasmic pH of L. vaginalis (pH 7.5) allowed 2-indolecarboxylic acid to chelate free ferrous ions released by nFeS, thereby protecting it from antibacterial effects, whereas pathogens such as S. Typhimurium with a lower cytoplasmic pH were susceptible (pH 6.5). Pretreatment of pigs and mice with L. vaginalis and nFeS protected them against Salmonella infection. Our findings provide a foundation for improving probiotic bacteria-based therapies against intestinal infections.
