The Research Team of Lei Xiaoguang from the School of Chemistry Has Discovered a New Biopesticide Molecule

**Abstract:** Bacterial plant diseases pose a significant threat to agricultural productivity and ecological balance, causing symptoms such as leaf spots, wilting, and rotting, and often leading to substantial crop losses and broader economic and environmental impacts. The rapid evolution of antibiotic resistance among plant pathogens and the continuous mutation of these bacteria have rendered traditional pesticides less effective, necessitating the development of novel and environmentally friendly strategies for disease control. Addressing this challenge, a collaborative research team led by Professor Xiaoguang Lei from the College of Chemistry and Molecular Engineering at Peking University and the Peking-Tsinghua Center for Life Sciences, and Researcher Jianmin Zhou from the Institute of Genetics and Developmental Biology at the Chinese Academy of Sciences and the National Laboratory of Yazhou Bay, has made a groundbreaking discovery. Their findings, published in the journal *Science* on February 28, 2025, introduce a new class of natural plant defense compounds, erucamide, which effectively combat bacterial infections by uniquely disrupting the assembly of the bacterial Type III secretion system (T3SS). Erucamide, a natural product found in various crops including rice and soybeans, is produced in significant quantities when plant immune responses are activated. This compound exhibits broad-spectrum antibacterial activity by specifically targeting and disabling the T3SS, a key virulence mechanism used by many plant pathogens to inject toxic effectors into host cells. Unlike conventional antibiotics that aim to kill bacteria, erucamide selectively reduces the pathogenicity of the bacteria, offering a safer and more sustainable approach to disease management. This method not only minimizes environmental pollution but also mitigates the risk of antibiotic resistance development, aligning with the principles of green agriculture. The research builds on previous collaborative efforts between the Lei and Zhou teams, which began in 2015. In 2020, they published a pioneering study in *Cell Host & Microbe* that identified another plant defense compound, sulforaphane (SFN), which inhibits the T3SS in plant pathogens. This foundational work laid the groundwork for the current discovery. The team's interdisciplinary expertise in chemical biology and plant innate immunity was crucial in isolating, purifying, and characterizing erucamide. They employed advanced techniques, including chemical proteomics, biochemical experiments, protein structure prediction, molecular docking, and molecular dynamics simulations, to elucidate the mechanism by which erucamide binds to and disrupts the HrcC protein, a critical component of the T3SS. The study demonstrates that erucamide's accumulation is a key defense mechanism against bacterial pathogens. It effectively protects crops from important bacterial diseases such as rice bacterial blight and tomato bacterial wilt, indicating its potential for widespread agricultural application. The discovery of erucamide and its unique mode of action represents a significant advancement in the field of plant resistance metabolites and provides a robust theoretical and technical foundation for the development of eco-friendly biopesticides and molecular breeding for disease resistance in crops. This research not only challenges the traditional understanding of plant defense mechanisms but also opens new avenues for the sustainable management of plant diseases. By focusing on the inhibition of bacterial virulence rather than direct bacterial killing, erucamide offers a novel strategy that could revolutionize the approach to crop protection. The collaborative effort, supported by various national research programs and institutions, underscores the importance of interdisciplinary research in addressing complex agricultural challenges and advancing green agricultural practices. **Key Events, People, and Locations:** - **Date of Publication:** February 28, 2025 - **Journal:** *Science* - **Title of the Paper:** "A widespread plant defense compound disarms bacterial type III injectisome assembly" - **Lead Researchers:** Professor Xiaoguang Lei (Peking University) and Researcher Jianmin Zhou (Chinese Academy of Sciences) - **Institutions:** College of Chemistry and Molecular Engineering, Peking University; Peking-Tsinghua Center for Life Sciences; Institute of Genetics and Developmental Biology, Chinese Academy of Sciences; National Laboratory of Yazhou Bay - **Previous Work:** Breakthrough study in *Cell Host & Microbe* (2020) on sulforaphane (SFN) and its inhibition of the T3SS - **Techniques Used:** Chemical proteomics, biochemical experiments, protein structure prediction, molecular docking, and molecular dynamics simulations - **Key Compound:** Erucamide - **Target Pathogen Mechanism:** Type III secretion system (T3SS) - **Impact:** Potential for developing eco-friendly biopesticides and molecular breeding strategies to enhance crop resistance **Summary:** The research by Lei and Zhou's teams has identified a new plant defense compound, erucamide, which disrupts the T3SS of plant pathogens, thereby reducing their virulence without directly killing the bacteria. This discovery, published in *Science*, offers a promising and sustainable strategy for managing bacterial plant diseases, contributing to the development of green agricultural practices and addressing the growing issue of antibiotic resistance. The interdisciplinary approach and advanced techniques used in this study highlight the potential for further innovations in plant defense mechanisms and biopesticide development.