论文部分内容阅读
Exogenous trehalose is significantly utilized and accumulated by Pseudomonas sp.HF-1 during its degradation of nicotine.To understand the mechanism underlying the protection conferred by this disaccharide on strain HF-1 under nicotine stress,we characterized the changes in antioxidative enzymes and the bacterial metabolome that develop in strain HF-1 cells cultured in the presence of nicotine and exogenous trehalose.The results of a combined enzymatic and NMR-based metabolomic approach showed that exogenous trehalose reversed the enhancement of catalase activity, the depletion of putrescine and glutamate, and the nicotine-induced accumulation of intracellular trehalose and maltose,all in a concentration-dependent manner.These findings show that exogenous trehalose alleviates nicotine-related oxidative stress in strain HF-1.In addition, the strong disturbances in succinate levels in cells cultured with 5 mM trehalose point out the need to consider the exogenous trehalose concentration when this sugar is used to mitigate nicotine-induced oxidative stress in strain HF-1.This is the first study in which an NMR-based metabolomic analysis was used to show that an exogenous organic solution acts as a de facto antioxidant when used, for example, to ameliorate the culture conditions of nicotine-degrading bacteria.