Sulfate-reducing bacteria block cadmium and lead uptake in rice by regulating sulfur metabolism.

This article focuses on the role of sulfate-reducing bacteria (SRB) in enhancing rice resistance to heavy metal contamination, specifically cadmium (Cd) and lead (Pb). Researchers constructed synthetic SRB communities based on strain functionality and identified the community SYN1 as most effective in reducing Cd and Pb uptake in rice by 36.60–39.88% and 35.96–51.54%, respectively, in hydroponic experiments. Both SYN1 inoculation and exogenous addition of reduced glutathione (GSH), a sulfur-containing antioxidant produced by SRB, similarly enhanced rice antioxidant enzyme activities, lignin content, and expression of genes related to phenylpropane biosynthesis, while downregulating heavy metal transporter genes, thereby mitigating heavy metal toxicity. The study concludes that SRB-mediated GSH production plays a key role in chelating heavy metals and inducing systemic resistance, offering a promising microbial strategy for managing heavy metal stress in crops.