Bharathkumar RAJAGOPAL

Bacterial consortia with extracellular polysaccharides (EPS) serves as key functional components in sustainable wastewater treatment and pollutant removal. This study integrates kinetic modelling and synthetic biology to optimize EPS production and nitrogen removal in a bacterial consortium enriched from domestic wastewater. Employing Monod and Verhulst models, consortia growth was simulated under controlled nitrogen flux (10 ppm NH4Cl), achieving a maximum biomass concentration (OD590 = 5.39) and EPS yield of 2.63 g/mL by day 45. SEM analysis revealed progressive biofilm maturation, transitioning from sparse aggregates to dense EPS-embedded matrices. Nitrogen flux analysis demonstrated efficient substrate utilization, with 80% ammonia oxidized by autotrophic populations (AOB/NOB). PCR amplification confirmed the presence of the exoY gene, central to EPS biosynthesis, enabling the design of a BUFFER-gate logic circuit to regulate succinoglycan production. The consortium’s dual capacity for nitrification and denitrification, coupled with high EPS yields, underscores its potential for enhancing wastewater treatment efficiency and biofilm engineering. These findings provide a framework for leveraging microbial consortia in bioremediation and industrial biotechnology through targeted genetic and kinetic optimisation.