Artificially constructed multifunctional complexes for enhanced atrazine removal and metabolic adaptation at low temperatures

The removal of contaminants and plant growth in agricultural fields are often negatively stressed by cold stress. In this study, by constructing a multifunctional complex [Peribacillus simplex C1, the atrazine degrading bacterium Acinetobacter lwoffii DNS32 and the plant promoting bacterium Enterobacter sp. P1 (C1/P1/DNS32)] it was found that the consortium of different abundance species performed better than the degrading bacteria alone under cold stress. Compared to strain DNS32, C1/P1/DNS32 with an optimal initial composition ratio of 5:1:2 at 72 h showed a 0.55-fold increase in the degradation of atrazine, a 3.37-fold decrease in the accumulation of the intermediate metabolite cyanuric acid and a 1.45-fold increase in its phosphorus solubilization capacity after seven days of incubation. Based on metabolome sequencing technology, the mechanism of action between strains in C1/P1/DNS32 was explored in terms of metabolic responses and cross-feeding. In addition, the addition of C1/P1/DNS32 significantly improved nutrient uptake and stress tolerance in soybean seedlings under ambient and low temperature soil culture. These findings contribute to the understanding of the function of multifunctional complex flora in a broader context and provide new insights into the rational construction of microbial consortia that facilitate bioremediation.