Data_Sheet_1_Integrated Metabolomics and Targeted Gene Transcription Analysis Reveal Global Bacterial Antimonite Resistance Mechanisms.docx

Antimony (Sb)-resistant bacteria have potential applications in the remediation of Sb-contaminated sites. However, the effect of Sb(III) exposure on whole-cell metabolic change has not been studied. Herein, we combined untargeted metabolomics with a previous proteomics dataset and confirmatory gene transcription analysis to identify metabolic responses to Sb(III) exposure in Agrobacterium tumefaciens GW4. Dynamic changes in metabolism between control and Sb(III)-exposed groups were clearly shown. KEGG pathway analysis suggested that with Sb(III) exposure: (1) the branching pathway of gluconeogenesis is down-regulated, resulting in the up-regulation of pentose phosphate pathway to provide precursors of anabolism and NADPH; (2) glycerophospholipid and arachidonic acid metabolisms are down-regulated, resulting in more acetyl-CoA entry into the TCA cycle and increased capacity to produce energy and macromolecular synthesis; (3) nucleotide and fatty acid synthesis pathways are all increased perhaps to protect cells from DNA and lipid peroxidation; (4) nicotinate metabolism increases which likely leads to increased production of co-enzymes (e.g., NAD+ and NADP+) for the maintenance of cellular redox and Sb(III) oxidation. Expectedly, the total NADP+/NADPH content, total glutathione, and reduced glutathione contents were all increased after Sb(III) exposure in strain GW4, which contribute to maintaining the reduced state of the cytoplasm. Our results provide novel information regarding global bacterial responses to Sb(III) exposure from a single gene level to the entire metabolome and provide specific hypotheses regarding the metabolic change to be addressed in future research.

对锑（Sb）具有抗性的细菌在锑污染场地的修复中具有潜在的应用价值。然而，锑(III)暴露对细胞整体代谢变化的影响尚未得到研究。本研究中，我们将非靶向代谢组学分析与先前获得的蛋白质组学数据集及基因转录分析相结合，以确认草生杆菌（Agrobacterium tumefaciens）GW4对锑(III)暴露的代谢反应。控制组与锑(III)暴露组之间的代谢动态变化得到了清晰的展示。KEGG通路分析表明，在锑(III)暴露的情况下：（1）糖异生途径的分支被下调，导致磷酸戊糖途径的上调，以提供合成代谢和NADPH的前体；（2）甘油磷脂和花生四烯酸代谢被下调，导致更多的乙酰辅酶A进入三羧酸循环，提高了产生能量和生物大分子合成的能力；（3）核苷酸和脂肪酸合成途径均有所增加，可能旨在保护细胞免受DNA和脂质过氧化的损害；（4）烟酸代谢增加，这可能导致辅酶（如NAD+和NADP+）的生成增加，以维持细胞氧化还原和锑(III)氧化的稳定状态。预期地，在GW4菌株中，锑(III)暴露后总NADP+/NADPH含量、总谷胱甘肽和还原型谷胱甘肽含量均有所增加，这有助于维持细胞质还原态。我们的研究结果为从单个基因水平到整个代谢组的全局细菌对锑(III)暴露的反应提供了新颖的信息，并为未来研究中需解决的代谢变化提供了具体假设。