Streptomyces coelicolor-plant association facilitates ergothioneine (EGT) uptake in Triticum aestivum

The growing market of agricultural biologicals as alternatives to synthetic crop chemicals is driven by their ability to improve soil health, reduce carbon footprints, enhance crop yield and quality, and help counter declining protein levels in cereal crops linked to climate change and soil degradation. Ergothioneine (EGT), an amino acid with recognized nutraceutical and micronutrient properties, has gained popularity for its anti-inflammatory and antimicrobial properties on human health. While plants and humans cannot biosynthesize EGT, its production by Streptomyces coelicolor presents as a promising bio-stimulant to support overall plant health and human health. Our study investigates the potential for Streptomyces coelicolor M145 to enhance EGT levels in spring wheat (Triticum aestivum). Results confirmed successful EGT extraction from bacterial cell extracts and plant tissues. Additionally, a fluorescent confocal microscopy staining and imaging protocol showed bacterial colonization on T. aestivum and its potential as a root endophyte. Following root inoculation, S. coelicolor was observed inhabiting roots, shoots, and internodes of T. aestivum, suggesting its potential endophytic lifestyle on host plants. Our data showed that S. coelicolor-associated wheat plants produce EGT in planta. Overall, our findings establish a direct link between soil and human health through rhizosphere colonization by S. coelicolor and in planta production of EGT, suggesting an alternate route to enhance protein concentration in crop plants.