Single Alkyl Chain Cationic Antifungals Targeting Mitochondria
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current antifungal compounds face challenges such as rapid development of fungicide resistance, limited efficacy against certain fungi, and toxicity concerns, necessitating the development of novel antifungals with new modes of action that are environmentally benign and have low mammalian toxicity.
Innovation Solution
The use of single alkyl chain cationic antifungal compounds, specifically C18-dimethyl sulfonium (C18-DMS+) and C18-trimethyl ammonium (C18-TMA+) derivatives, which target fungal mitochondria by inhibiting oxidative phosphorylation, inducing mitochondrial reactive oxygen species, and triggering programmed cell death, while maintaining low toxicity to humans and the environment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional antifungal compounds (azoles, SDHIs, strobilurins) are used, then fungal diseases can be controlled, but fungicide resistance develops rapidly
Solution Approach 1:
The invention changes the chemical structure parameters of antifungal compounds by using single alkyl chain cationic compounds with long alkyl chains (C12-C32) instead of conventional azoles or SDHIs. This structural parameter change results in a novel mode of action that disrupts fungal mitochondrial function rather than targeting ergosterol biosynthesis or respiration chain complexes, thereby overcoming resistance issues
Solution Approach 2:
The invention converts the naturally occurring phenomenon of lipophilic cation accumulation in mitochondria (which can be harmful due to ROS production) into a beneficial antifungal mechanism. By designing cationic compounds with specific alkyl chain lengths, the invention exploits mitochondrial ROS production and membrane depolarization to trigger programmed cell death in fungi while maintaining selectivity against mammalian cells
2Adaptability or versatility
If lipophilic cations are used to target mitochondria, then novel mode of action is achieved, but toxicity to mammals increases
Solution Approach 1:
The invention applies local quality by designing compounds with specific alkyl chain lengths (C12-C32) that determine their distribution and accumulation patterns. The long alkyl chain provides lipophilicity for mitochondrial targeting while the cationic head group enables electrostatic interaction with the negative mitochondrial membrane potential. This localized structural design achieves selective toxicity by concentrating the active compound in fungal mitochondria while limiting mammalian cell accumulation
Solution Approach 2:
The invention changes physical-chemical parameters including alkyl chain length, cationic charge density, and lipophilicity to optimize the balance between antifungal activity and mammalian toxicity. By systematically varying these parameters, the invention identifies compounds that achieve sufficient mitochondrial accumulation in fungi while maintaining acceptable safety margins for mammalian applications
3Adaptability or versatility
If single alkyl chain cationic compounds are used, then resistance development is reduced, but compound design complexity increases
Solution Approach 1:
The invention segments the antifungal compound into two distinct functional parts: a cationic head group (for electrostatic interaction with mitochondrial membrane) and a long alkyl chain (for lipophilicity and membrane insertion). This segmentation simplifies the design process by allowing independent optimization of each segment's properties to achieve the desired balance between antifungal activity, mitochondrial targeting, and toxicity reduction
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
These compounds demonstrate enhanced antifungal activity against crop pathogens and human fungal infections, offering a multi-site mode of action that reduces resistance development and improves protection against fungal diseases with reduced environmental and human toxicity.
Implementation Method 1
Electron-transfer through the respiration chain triggers proton transport across the inner mitochondrial membrane. This leaves the matrix negatively charged and, as such, it becomes a target for lipophilic cations.
Implementation Method 2
Oxidative phosphorylation depends on electron transfer through the mitochondrial respiration chain complexes in the inner mitochondrial membrane
Implementation Method 3
Mitochondria also produce reactive oxygen species (mROS) at complex I and III, which, if deregulated, can damage proteins and lipids in the inner mitochondrial membrane
Implementation Method 4
Increasing evidence suggests that such a programmed cell death pathway exists in fungi and targeting this pathway is a promising strategy to develop novel antifungals.
Data Source
AI summary
The invention provides an antifungal composition comprising an antifungal compound of formula R—S+(R′)2 or R—N+(R′)3 wherein R is C17-C32 straight chain or branched alkyl; and each R′ is independently methyl, ethyl, propyl, isopropyl or butyl; and uses of said composition as antifungal agents.