PHA production by denitrifying bacteria

For the first time, we proposed a hydrogen-driven platform enabling simultaneous hydrogenotrophic denitrification and polyhydroxyalkanoates production, in a hydrogen-based membrane biofilm reactor (H2-MBfR). Remarkably, the platform achieved a >99% hydrogen gas utilization rate, >99% removal of 4 mM nitrate, and a 36% polyhydroxyalkanoates (PHA) production ratio (dry cell weight) in a continuous operation with a hydraulic retention time of 4 hours. Our research investigated the DNA sequencing of biofilm sample and inoculumn sludge providing detailed metagenomic data, which explored the metabolic pathways involved in hydrogen utilization, denitrification, CO2 fixation, and PHA production.