Coordination of fungal biofilm development by extracellular vesicle cargo

Area of Science:

• Microbiology
• Mycology
• Biochemistry

Background:

• Candida albicans forms protective biofilms, hindering antifungal treatments.
• Extracellular vesicles (EVs) secreted by C. albicans contribute to biofilm development and drug resistance.

Purpose of the Study:

• To identify and characterize the functions of extracellular vesicle (EV) cargo proteins in Candida albicans biofilm formation, drug resistance, adhesion, and dissemination.
• To understand the role of EVs in coordinating fungal community behavior.

Main Methods:

• Machine-learning analysis of proteomic data from EV-deficient mutants to identify candidate cargo proteins.
• Construction and analysis of mutant and complemented strains to assess biofilm matrix accumulation, antifungal drug resistance, adhesion, and dispersion.
• Complementation assays using exogenous wild-type EVs to validate protein function.

Main Results:

• Identified 63 candidate EV cargo proteins, with 17 mutants showing reduced biofilm matrix and antifungal resistance.
• Discovered 8 cargo mutants with defects in adhesion and/or dispersion.
• Demonstrated that exogenous EVs can restore wild-type phenotypes in mutant strains, confirming EV cargo function.
• Found that most identified cargo proteins play roles in multiple biofilm developmental stages.

Conclusions:

• Extracellular vesicles (EVs) act as crucial mediators for community coordination during Candida albicans biofilm development.
• EV cargo proteins are essential for biofilm matrix assembly, antifungal drug resistance, cell adhesion, and dissemination.
• Targeting EV-mediated communication presents a potential strategy to combat Candida albicans infections.