Myxochelin-based ferroptosis inhibitors for rice blast disease control

Overview

Rice blast disease, caused by the fungal pathogen Pyricularia oryzae, is one of the most destructive diseases affecting global rice production. This research proposes a novel antifungal strategy that targets ferroptosis, an iron-dependent form of cell death driven by lipid peroxidation, within the pathogen itself. By inhibiting the ferroptotic mechanisms that occur during pathogenesis, the approach aims to suppress infection at a critical stage of fungal development. The research builds on a library of synthetic myxochelin derivatives, a family of catecholate-type natural molecules originally isolated from Myxobacteria, which function as iron-chelating agents. Preliminary testing has identified a lead compound that inhibits mature appressorium formation in a dose-dependent manner, highlighting the importance of halogen substitution on the aromatic moiety for biological activity.

Technical specifications

The research leverages the following technical elements:

• Target pathway: Ferroptosis in Pyricularia oryzae, specifically lipid peroxidation and iron-dependent NADPH oxidase activity that drive conidial cell death during pathogenesis
• Compound library: A small library of natural and nature-inspired myxochelin derivatives, including symmetrical and unsymmetrical variants synthesized via amide coupling between protected amino acids and substituted aromatic or heteroaromatic acids
• Lead compound characteristics: Demonstrated dose-dependent inhibition of mature appressorium formation at concentrations of 10, 100, and 1000 μM in methanol, with halogen-bearing aromatic moieties identified as critical for activity
• Future development pathways: Structural modification of the core skeleton, evaluation against strobilurin-resistant strains, mechanism-of-action studies, and exploration of additional antioxidant and iron-chelating compounds
• Green chemistry approaches: Biotransformations and click chemistry-based hybrid compound design for sustainable synthesis of new derivatives

Technology readiness level

The technology is at an early research stage. A lead compound has been identified through preliminary biological assays against wild-type Pyricularia oryzae PO21_07, demonstrating dose-dependent inhibition of appressorium formation. Further validation is planned, including structural optimization of the lead compound, expanded testing against strobilurin-resistant strains, and mechanistic studies to elucidate the mode of action. Additional compound classes and green chemistry synthesis routes will also be explored.