Functional profiling of abundant glycosyltransferases in the rhizospheric bacteriome of Abutilon fruticosum

Abstract

In this study, we undertook an extensive exploration of the rhizospheric bacteriome of Abutilon fruticosum, focusing on the activities of Carbohydrate-Active Enzymes (CAZymes) of class glycosyltransferases (GTs), and their potential impact on plant growth and fortification against environmental adversities and soil-borne pathogens. Investigation revealed a predominance of families GT1, GT31, GT35, GT39, and GT51, mainly ascribed to bacterial genera Microvirga, Arthrobacter, Blastococcus, Bacillus, Nocardioides, and Kocuria. Our findings unveiled the pivotal role of phenylalanine, mostly exuded by plant roots, serving as the primary substrate for the catalytic activities of the identified CAZymes. With glucosylation emerging as the predominant enzymatic function, we propose UDP-D-glucose as the central core intermediate metabolite, orchestrating a multifaceted network of interrelated metabolic pathways. Subsequent profiling delineated a diverse array of metabolites synthesized by 10 CAZymes actively participating in 10 crosstalking pathways. Functional analyses of these metabolites underscore their significance in the biosynthesis of flavonoids, anthocyanins, and related derivatives, crucial for the reproductive success of plants by serving as visual cues for insect pollinators and conferring protection against deleterious effects of radiation. Certain other metabolites play vital roles in reinforcing the structural integrity of plant cell walls, thus enhancing resistance against enzymatic degradation while augmenting cytokinin activity. In conclusion, our study elucidates a novel paradigm of plant-bacteria mutualistic interaction, offering insights into the intricate mechanisms underlying plant-microbe symbiosis. We posit that the integration of high-throughput technologies with metabolic engineering strategies presents a promising approach for applying cost-effective and environmentally benign alternatives to conventional agricultural practices. (249 words).