Microbes work together to form drug-tolerant communities
- Microbial communities comprise cells with different metabolic capacities and may include auxotrophs.
- Auxotroph is an organism, usually a mutant bacteria, that cannot synthesize substances needed for its growth and metabolism.[1]
- Researchers analyzed amino acid biosynthesis pathways in auxotroph from microbiome data of more than 12,000 natural microbial communities.
- Researchers also examined the auxotrophic-prototrophic interactions in yeast communities.
- Researchers discovered a mechanism that links auxotrophs to an increase in metabolic interactions and anti-microbial drug tolerance.
- The auxotrophs have been observed to obtain altered metabolic flux distribution, export more metabolites, and as a result, enrich the community in metabolites.
- Metabolites are intermediate or end-product substances produced by metabolism.
- These capabilities observed from auxotrophs may be the consequence of the metabolic adaptations required to use specific metabolites.
- Additionally, researchers observed that the increased metabolite exportation was correlated with the decrease in intracellular drug concentrations.
- The reduction of intracellular drug concentration allows microbes to grow even at drug levels above minimal inhibitory concentrations.
- Minimal inhibitory concentration is the lowest concentration of drugs that can inhibit the growth of bacteria.[2]
- Researchers demonstrated that an antifungal compound called azoles did not significantly eliminate yeast cells that use metabolites from a metabolically-enriched environment.
- The results describe a mechanism that enhances our understanding of why cells are more tolerant to drug exposure when they metabolically interact.
Sources:
Yu, J.S.L., Correia-Melo, C., Zorrilla, F. et al. Microbial communities form rich extracellular metabolomes that foster metabolic interactions and promote drug tolerance. Nat Microbiol (2022). https://doi.org/10.1038/s41564-022-01072-5
[1] https://www.thefreedictionary.com/auxotroph
[2] https://en.wikipedia.org/wiki/Minimum_inhibitory_concentration
