An Evolutionarily Conserved Laterally Acquired Toolkit Enables Microbiota Targeting by Trichomonas.

Area of Science:

• Microbiology
• Evolutionary Biology
• Eukaryotic Cell Biology

Background:

• Trichomonas species are microbial eukaryotes (protists) that live symbiotically on mucosal surfaces.
• These protists are associated with various inflammatory diseases in diverse hosts, which also harbor resident microbiota.
• The evolutionary history of Trichomonas involves host transfers, including zoonotic events from birds to mammals.

Purpose of the Study:

• To investigate the molecular mechanisms by which Trichomonas gallinae interacts with bacterial members of the microbiota.
• To identify a conserved molecular toolkit in Trichomonas species for microbiota interaction.
• To understand the role of these interactions in host adaptation and inflammatory mucosal diseases.

Main Methods:

• Comparative transcriptomics of Trichomonas gallinae co-cultured with Escherichia coli.
• Integration of transcriptomic data with comparative genomics and phylogenetics.
• Analysis of conserved protein-coding genes, including those acquired through lateral gene transfer (LGTs).

Main Results:

• Identified a molecular toolkit in Trichomonas species for interacting with bacteria.
• Discovered conserved genes encoding muramidases, glucosaminidases, and antimicrobial peptides, likely acquired through LGTs in an avian ancestor.
• These effectors target bacterial cell walls, influencing microbiota composition in avian and mammalian hosts.

Conclusions:

• Trichomonas species possess a toolkit to actively compete with and exploit their associated microbiota for nutrients.
• This molecular toolkit may contribute to dysbiosis in Trichomonas infections and influence inflammatory mucosal diseases.
• The ability to target bacterial populations aids Trichomonas adaptation to diverse hosts.