We are grateful for funding by @vetenskapsradet.bsky.social @erc.europa.eu @kawresearch.bsky.social Kempestiftelserna and Jeanssons stilftelse

This work was led by our talented postdoc Bolor Buyanbadrakh with the help of others in our lab, and the labs of Madeleine Ramstedt, Björn Schröder (@mucubacter.bsky.social) and Sun Nyunt Wai.

Our mechanistic follow-up unveiled that guanine could boost the pH increasing effect of V. parvula.
Amazingly, this worked even in three-member communities of a pH lowering strain, a strain sensitive to low pH and V. parvula to rescue the growth.

Then we turned our focus to the overall trend of most phyla to grow worse in spent media that has low pH.
An exception to this was Veillonella parvula, which can cope well with low pH. We observed that V. parvula can increase spent media pH and allow low pH-sensitive Bacteroidota species to grow.

We followed up on one of the rare positive interactions, and observed that Clostridium perfringens promotes the growth of Mediterraneibacter gnavus through extracellular vesicles.

We used a spent medium approach to profile the growth interactions, and as previously observed in different ecosystems, we observed mostly negative interactions. These reflect species occupying the same metabolic niche and competing for nutrients, or altering the environment (e.g., lowering pH).

Check more details about the ENDAMR doctoral network here: endamr.eu

In this project the candidate will look at drug resistance mechanisms in microbiome species.