Early-stage adaptation of pristine soil microbiota to Tetrabromobisphenol A: Unveiling rapid succession and ecophysiological mechanisms.

Abstract

Addressing the limitations of existing studies that predominantly isolate Tetrabromobisphenol A (TBBPA)-degrading bacteria from contaminated environments and focus on degradation characteristics, this study employed multi-omics approaches to systematically elucidate the dynamic succession patterns and metabolic adaptation mechanisms of microbial communities from pristine soil under acute TBBPA stress, and achieved rapid screening of functional degraders. The results showed that TBBPA concentration and exposure time jointly drove community structural reconstruction, in which Methylobacillus and Pannonibacter, owing to their strong tolerance and high abundance, emerged as potential core degraders. Functional analysis indicated that high-concentration TBBPA (200 mg/L) reduced the abundance of the DLD gene by nearly 60%, whereas the community effectively alleviated energy metabolism inhibition through upregulation of upstream tricarboxylic acid cycle genes (CS, IDH3, and ACO) and respiratory chain functional genes (ccoN and ccoO), and formed a more tightly connected interaction network to enhance functional synergy. Metabolomic analysis revealed significant accumulation of membrane repair-related lipids (Gpetn and Lysopa) and amino acids (Norleucine and L-Phenylalanine), while pathways related to ABC transporters were activated, jointly confirming a stress adaptation mechanism centered on membrane repair and defense responses in the microbial community. The degradation process exhibited a multi-enzyme synergistic characteristic, with glutathione S-transferase playing a dominant role. After acclimation, the degradation efficiency of the microbial community was significantly improved, and the key strain Acinetobacter sp. T3 was successfully isolated. This study provides a theoretical basis and soil microbial communities for the development of in situ bioremediation technologies targeting persistent organic pollutants (POPs).