Rhizosphere-derived Glycoside Hydrolases: A Biotechnological Treasure Trove from Arid Plant Ecosystems

Abstract

Wild plant-associated rhizospheric microbiomes represent largely unexplored reservoirs of carbohydrate-active enzymes (CAZymes) that have significant biotechnological potential. This metagenomic investigation examined glycoside hydrolase (GH) family distribution within rhizospheric microbial assemblages of two native Saudi Arabian plants: Moringa oleifera and Abutilon fruticosum. High-throughput shotgun sequencing revealed pronounced plant species-specific CAZyme specialization. Moringa oleifera rhizospheres exhibited exclusive enrichment in five GH families (GH105, GH106, GH25, GH28, and GH38), while A. fruticosum supported three distinct families (GH17, GH32, and GH33). Taxonomic analysis revealed differential microbial composition: M. oleifera communities were dominated by Actinobacteria (Streptomyces, Micromonospora) with significant eukaryotic representation, whereas A. fruticosum microbiomes showed bacterial predominance, primarily Proteobacteria (Pseudomonas, Bradyrhizobium). CAZyme-encoding sequences frequently exceeded 120 per GH family, indicating extensive catalytic potential. These specialized enzymes offer multifaceted applications across pharmaceutical glycoprotein synthesis, lignocellulosic biomass degradation for biofuels, food preservation systems, and biomaterial fabrication for tissue regeneration. The rhizosphere-specific enrichment of highly specialized CAZyme consortia positions these microbial communities as scalable biocatalytic platforms, providing eco-sustainable alternatives to conventional industrial methodologies across pharmaceutical, energy, food, and environmental sectors.