Mining the Galium aparine L. microbiome: genome-guided discovery and experimental validation of metallophore-producing endophytic bacteria

BACKGROUND: Environmental pollution resulting from heavy metals constitutes a critical global issue. Remediation technologies offer potential solutions, particularly through the innovative use of endophytic microbes, either independently or in conjunction with plants. This solution is based on the ability of certain endophytic bacteria to produce metallophores, which are low-molecular-weight compounds capable of chelating various heavy metals. METHODS: . Moreover, we examined in detail of their metallophore gene clusters, their organization, diversity and prevalence, by broad homology search. RESULTS: . An in-depth analysis of the biosynthetic gene clusters and enzymes involved in metallophore biosynthesis revealed homologous clusters within previously deposited genomes, highlighting their distribution and potential evolutionary conservation. CONCLUSIONS: The strains demonstrated capacity for metallophore production and heavy metal chelation, which makes them promising candidates for the development of advanced microbial solutions. A genome-guided selection approach can guide the selection of strains for agricultural applications, where they enhance plant nutrient uptake, suppress soil pathogens, and support sustainable fertilization strategies beyond sequestering crucial metals. Apart from agriculture, purified metallophores can aid bioremediation and mobilization of heavy metals from various environments and matrices.