Broad-Spectrum Co-Metabolic Substrates Enhance the Bioremediation of 1,2,3-Trichloropropane in Groundwater by a Non-Dehalogenimonas Consortium.

1,2,3-Trichloropropane (TCP), a highly mobile chemical byproduct, has severely exacerbated groundwater environment deterioration. Due to the lack of effective natural attenuation pathways, TCP typically exhibits a fate of persistent retention within aquifers. To address this challenge, instead of relying on limited specific strains, this study focused on exploring broad-spectrum co-metabolic substrates to enhance the degradation efficiency of a non-Dehalogenimonas synergistic consortium optimized through long-term directed domestication. Results indicated that the average degradation rate of the domesticated consortium increased to 19.06 μmol L-1 d-1, achieving complete removal within 3.5 days, thereby effectively altering the environmental persistence of TCP. Microbial community and metagenomic analyses revealed that this transformation process was driven by a synergistic alliance comprising Fusibacter, Desulfovibrio, Nitratidesulfovibrio, and Parabacteroides, realized through a coupled metabolic module of "hydrogen production, cofactor synthesis, and reductive dechlorination". Crucially, the consortium demonstrated exceptional broad-spectrum adaptability to various co-metabolic substrates, where sodium acetate and lactate significantly enhanced the degradation efficiency. This study confirms that utilizing suitable co-metabolic substrates can effectively activate the non-Dehalogenimonas consortium to regulate the migration and fate of pollutants in complex groundwater environments, offering an efficient bioremediation strategy to arrest groundwater contamination.