Impacts of temperature on hydrogenotrophic denitrifying aquifer microbiota.

Hydrogen-stimulated denitrification in aquifer microbiota remains effective across 12–25°C, driven by a dominant Acidovorax defluvii strain with specialized hydrogen-oxidizing genes.

• Why it matters: Groundwater nitrate pollution poses a global threat to drinking water safety, and sustainable remediation methods are urgently needed. Understanding microbial responses to environmental conditions is crucial for optimizing in situ bioremediation strategies.
• What they did: Researchers enriched native hydrogenotrophic denitrifiers from nitrate-polluted aquifer sediments using microcosm incubations at four temperatures, measuring denitrification rates and analyzing community composition through metagenomics.
• The result: The study found consistent nitrate removal across temperatures, with a single Acidovorax strain dominating and possessing transferable hydrogen oxidation genes, indicating hydrogen injection as a reliable, temperature-resilient remediation approach.