Plant-associated Streptomyces detoxify the mycotoxin fusaric acid by amino acid conjugation
Streptomycetes are prevalent members of soil and plant microbiomes, yet how they cope with toxins produced by root-infecting fungal pathogens remains poorly understood. Plant pathogenic Fusarium species produce the mycotoxin fusaric acid (FA) that contributes to virulence and perturbs rhizosphere microbiome dynamics. Here, we show that root-colonising Streptomyces sp. ATMOS43 neutralizes FA…
Plant-associated Streptomyces bacteria possess the ability to detoxify the mycotoxin fusaric acid (FA) produced by the root-infecting fungal pathogen Fusarium. This detoxification process occurs through amino acid conjugation, where FA forms single amino acid and dipeptidyl bonds with specific amino acids, most notably FA-Ser. The presence of FA-Ser significantly reduces the toxicity of fusaric acid in both laboratory and plant environments.
Proteomic and physiological assessments reveal that fusaric acid's toxicity, at least in part, involves the chelation of zinc, a process that is effectively blocked by the conjugation of fusaric acid to serine. Furthermore, when these Streptomyces bacteria co-cultivate with Fusarium-sensitive streptomycetes, the presence of FA is diminished, highlighting the role of amino acid conjugation in mitigating the impact of fusaric acid on the plant microbiome.
In summary, these findings underscore the protective capabilities of plant-associated Streptomyces bacteria against Fusarium's virulence factor, fusaric acid.
Written by urgent.news from bioRxiv's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
