Publication Date:
2024-01-16
Description:
Ingestion of the cycad toxins \xce\xb2-methylamino-L-alanine (BMAA) and azoxyglycosides is harmful to diverse organisms. However,
\nsome insects are specialized to feed on toxin-rich cycads with apparent immunity. Some cycad-feeding insects possess a common
\nset of gut bacteria, which might play a role in detoxifying cycad toxins. Here, we investigated the composition of gut microbiota
\nfrom a worldwide sample of cycadivorous insects and characterized the biosynthetic potential of selected bacteria. Cycadivorous
\ninsects shared a core gut microbiome consisting of six bacterial taxa, mainly belonging to the Proteobacteria, which we were able
\nto isolate. To further investigate selected taxa from diverging lineages, we performed shotgun metagenomic sequencing of cocultured bacterial sub-communities. We characterized the biosynthetic potential of four bacteria from Serratia, Pantoea, and two
\ndifferent Stenotrophomonas lineages, and discovered a suite of biosynthetic gene clusters notably rich in siderophores. Siderophore
\nsemi-untargeted metabolomics revealed a broad range of chemically related yet diverse iron-chelating metabolites, including
\ndesferrioxamine B, suggesting the occurrence of an unprecedented desferrioxamine-like biosynthetic pathway that remains to be
\nidentified. These results provide a foundation for future investigations into how cycadivorous insects tolerate diets rich in
\nazoxyglycosides, BMAA, and other cycad toxins, including a possible role for bacterial siderophores.
Keywords:
Microbial ecology
;
Microbiome
Repository Name:
National Museum of Natural History, Netherlands
Type:
info:eu-repo/semantics/article
Format:
application/pdf
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