Metabolic shift and enhanced electron transfer in sulfate-reducing bacteria induced by corrosion-biomineralized iron sulfide nanoparticles.

While SRB-induced biocorrosion is well-documented, the reciprocal influence of metallic corrosion and its mineral products on SRB metabolism remains underexplored. This study investigated the interactions between Q235 steel corrosion, biomineralization products, and the metabolic activity of Desulfovibrio bizertensis SY-1. Results indicated that Q235 steel corrosion significantly altered the bacterial metabolic mode. Specifically, iron sulfide nanoparticles generated during the corrosion process facilitated extracellular electron transfer. Conversely, under iron-limited conditions (absence of steel), SRB upregulated transport systems, such as the ferric uptake regulator (Fur), while downregulating carbon metabolism pathways to ensure survival. These findings demonstrate that metallic iron corrosion not only provides essential nutrients but actively reshapes SRB bioenergetics and electron transport mechanisms. This work offers new insights into the coupling of biocorrosion and microbial metabolism.