Wheat landraces and microbiome endophytic phytases: In vitro/in silico study for iron bioavailability

This study proposes an innovative biotechnological strategy to enhance iron bioavailability in wheat by leveraging the untapped potential of phytase-producing endophytic lactic acid bacteria and yeasts isolated from Moroccan wheat landraces. The research was predicated on the hypothesis that the endophytic microbiota of indigenous wheat landraces possesses a specialized and highly efficient catalytic profile capable of surpassing the structural and kinetic limitations of endogenous wheat enzymes. To validate this hypothesis, the investigation involved: (<i>i</i>) molecular characterization of endophytes via 16S and 18S rRNA sequencing; (<i>ii</i>) quantification of specific phytase activity for ferric phytate degradation; (<i>iii</i>) identification of phytase-encoding genes; and (<i>iv</i>) molecular docking simulations to elucidate enzyme-substrate interactions. Findings confirmed the hypothesis, demonstrating that these microbial phytases possess a superior capacity for ferric phytate hydrolysis, significantly exceeding endogenous wheat activity. Three distinct microbial phytase classes were identified - Histidine Acid Phosphatase (HAP), Protein Tyrosine Phosphatase (PTP), and β-Propeller Phosphatase (βPP) - which complement the native Purple Acid Phosphatase (PAP) found in wheat. Molecular docking results further substantiated the hypothesis by revealing high binding affinities and identifying key catalytic residues within these microbial taxa. These results suggest that the identified strains can be utilized as bio-priming agents or functional fermentation starters to naturally biofortify wheat-based products, providing a scalable biotechnological solution to mitigate global iron deficiency.