Soil microbiome bacteria protect plants against filamentous fungal infections via intercellular contacts

• 成果类型: Article
• 署名作者: Lin, Long; Shen, Danyu; Shao, Xiaolong; Yang, Yicheng; Li, Li; Zhong, Caihong; Jiang, Jiandong; Wang, Mengcen; Qian, Guoliang
• 署名单位: Nanjing Agricultural University; Chinese Academy of Sciences; Wuhan Botanical Garden, CAS; Nanjing Agricultural University; Zhejiang University; Zhejiang University
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-9690
• DOI: 10.1073/pnas.2418766122
• 发表日期: 2025-01-21
• 关键词: systems; GROWTH

摘要

Bacterial-fungal interaction (BFI) has significant implications for the health of host plants. While the diffusible antibiotic metabolite- mediated competition in BFI has been extensively characterized, the impact of intercellular contact remains largely elusive. Here, we demonstrate that the intercellular contact is a prevalent mode of interaction between beneficial soil bacteria and pathogenic filamentous fungi. By generating antibiotics- deficient mutants in two common soil bacteria, Lysobacter enzymogenes and Pseudomonas fluorescens, we show that antibiotics- independent BFI effectively inhibits pathogenic fungi. Furthermore, transcriptional and genetic evidence revealed that this antibiotics- independent BFI relies on intercellular contact mediated by the type VI secretion system (T6SS), which may facilitate the translocation of bacterial toxic effectors into fungal cells. Finally, by using a conidia enrichment platform, we found that T6SS- mediated fungal inhibition resulting from intercellular contact naturally occurs within the soil microbiome, particularly represented by Pseudomonas fulva. Overall, these results demonstrate that bacteria from the soil microbiome can protect host plants from fungal infection through antibiotics- independent intercellular contacts, thus revealing a naturally occurring and ecologically important mode of BFI in agricultural contexts.