The Guild Model of CF Airway Microbial Ecology.

Ecological guilds are groups of organisms that utilize the same class of resources and occupy similar niches, regardless of their taxonomic identities. Here we propose the Guild Model for Cystic Fibrosis Airway Microbial Ecology, which considers the ecological function and wider role of each microbe in the ecosystem. This model consists of four functional guilds: (i) "Brewers" metabolize host-derived substrates (e.g., mucins) and produce fermentation products; (ii) "Drunkards" exploit the metabolic niche built by Brewers, consuming fermentation products and secreting exopolysaccharides to build biofilms; (iii) "Putrifiers" produce toxic compounds causing inflammation and tissue necrosis; and (iv) "Nihilists" are specialist pathogens characterized by intracellular or lytic life cycles and cytotoxin production. By focusing on microbial function and the broader community context, this model offers a refined framework for interpreting cystic fibrosis airway ecology. Although developed for CF, the Guild Model is adaptable to other diseases influenced by microbial ecology.