A host-adapted auxotrophic gut symbiont induces mucosal immunodeficiency (Part II)

The microbiome holds great promise as a source of novel therapeutic targets for many diseases. Mining for causative microorganisms that impact processes underlying disease states should utilize Koch’s postulates. Here we show a functional screen for the bacterial microbiota of intestinal immunoglobulin A (IgA)-deficient mice; we identified a novel Gram-negative bacterium, proposed to be named as Tomasiella immunophila that induces and degrades IgA in mouse intestine. T. immunophila is auxotrophic for the bacterial cell wall amino sugar N-acetylmuramic acid (MurNAc). T. immunophila secretes IgA-degrading enzymes into outer membrane vesicles that preferentially degrade rodent antibodies with kappa but not lambda light chains. We propose this study uncovers a new paradigm for the role of symbionts in immunodeficiency that can ultimately be applied to human disease., This dataset consists of a phylogenomic tree, generated using Phylophlan3., , # Tree from the manuscript: A host-adapted auxotrophic gut symbiont induces mucosal immunodeficiency

[https://doi.org/10.5061/dryad.j0zpc86p8](https://doi.org/10.5061/dryad.j0zpc86p8)

This tree highlights the separation of the novel genus, *Tomasiella*, from its close relatives within the family *Muribaculaceae*.

## Description of the data and file structure

The NEXUS file for the tree from our manuscript, Figure 2A, is available.

https://doi.org/10.5061/dryad.j0zpc86p8: Part 2: the NEXUS file for the tree from our manuscript, Figure 2A.

https://doi.org/10.5061/dryad.bvq83bkj9: Part 1: The data files include two separate zip files labeled “Raw data for main figures” and “Raw data for supplemental figures”. Each zip files contains all the raw data for each panel of the figures (except Fig. 2A) in the manuscript