Using coculture to detect chemically mediated interspecies interactions.

Area of Science:

• Microbiology
• Chemical Biology
• Systems Biology

Background:

• Bacteria in nature interact through secreted metabolites, influencing community structure and function.
• Understanding these chemically mediated interactions is crucial for microbial ecology.
• Previous methods lacked efficiency in identifying specific metabolite-producing organisms.

Purpose of the Study:

• To develop and validate a fluorescence-based coculture screen for identifying environmental microbes that produce metabolites.
• To detect metabolites that modulate specific bacterial phenotypes like biofilm formation.
• To facilitate the study of microbial community interactions and metabolite signaling.

Main Methods:

• A fluorescence-based coculture screen was developed using a transcriptional reporter strain.
• Reporter strains fluoresce when a specific phenotype is activated by diffusible metabolites from neighboring microbes.
• Environmental microbes are screened on solid media, with inducers identified as nonfluorescent colonies adjacent to fluorescent ones.

Main Results:

• The screen successfully identifies environmental microbes producing diffusible metabolites that activate specific physiological responses in a reporter strain.
• The method was optimized for screening soil organisms that induce biofilm matrix production in Bacillus subtilis.
• The publication provides a detailed protocol for implementing the coculture screen.

Conclusions:

• The developed coculture screen is an effective tool for discovering novel chemically mediated microbial interactions.
• This method enables the identification of specific metabolite-producing bacteria within complex environmental samples.
• The approach is adaptable for studying various bacterial species and phenotypes, advancing microbial community research.