Metabolic activity and BDE 28 degradation potential of Perinereis sp. gut microbiota

The rapidly increasing threats of bioaccumulation of persistent organic pollutants (POPs) in the marine environment have become a global concern. Benthic substratum of Gulf of Khambhat, India acts as a major sink for POPs from different sources which are readily uptaken and bioaccumulated in benthic invertebrates. Polychaetes are one of the abundant and highly tolerant benthic invertebrates that act as an indicator of coastal pollution. Microbial communities play a pivotal role in the degradation of contaminants in marine ecosystems. However, the interaction between pollutants and gut microbes in macroinvertebrates remain largely unexplored. This study aimed to investigate the metabolic activity of polychaete gut microbes and their responses to persistent organic pollutants. The functional diversity of the gut microbiota of Perinereis sp. was analyzed using their carbon source utilization profile, which revealed a significantly higher utilization rate for carbohydrates, polymers, and amines during a 72-h incubation period. Additionally, the isolated gut microbial strain PGC-2 demonstrated remarkable tolerance to high concentrations of BDE 28 and achieved complete degradation of 50 mg/L of the pollutant within 144 h. These findings highlight the potential of polychaete gut microbes in mitigating POP pollution in marine environments.