Fungal Hydrophobins: Taxonomic Distribution, Functional Roles, Physicochemical Properties, and Biotechnological Applications

Hydrophobins are small, cysteine-rich amphipathic proteins predominantly produced by filamentous fungi, known for their ability to self-assemble at hydrophobic–hydrophilic interfaces. These proteins are essential for fungal development, surface interactions, pathogenicity, and environmental adaptation, and they have attracted growing interest for biotechnological applications. In this work, we provide a narrative review of fungal hydrophobins, based on a systematic literature search and manual curation of eligible studies integrated with protein database records from Ascomycota and Basidiomycota. Information was compiled from peer-reviewed publications selected according to predefined eligibility criteria and complemented with UniProt records, covering taxonomic distribution, functional and biophysical properties, and physiological and pathogenic roles. Significant diversity in molecular features and physicochemical profiles was observed, indicating functional specialization across different ecological niches and lifestyles. Additionally, the compiled data highlight various biotechnological applications, such as surface modification, enzyme immobilization, drug delivery systems, biomaterial development, and environmentally sustainable technologies. By consolidating molecular, functional, and applied information across a wide range of fungal species, this review provides a comprehensive reference framework for hydrophobin research and biotechnological innovation.