pH plays a role in the mode of action of trimethoprim on Escherichia coli.
pH plays a role in the mode of action of trimethoprim on Escherichia coli.
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DOI：
10.1371/journal.pone.0200272
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发表时间：
2018
期刊：
影响因子：
3.7
通讯作者：
Goodacre R
中科院分区：
文献类型：
--
作者：
AlRabiah H;Allwood JW;Correa E;Xu Y;Goodacre R
代谢组学为基础的方法被应用到了解与大肠杆菌K-12在亚最低抑菌浓度（MIC分别为0.2，0.03和0.003 mg L-1）的甲氧苄啶的相互作用。甲氧苄啶抑制二氢叶酸还原酶，因此是核酸合成的间接抑制剂。由于甲氧苄啶的碱性，选择两个pH值水平（5和7），模拟健康尿液pH值。这也允许调查甲氧苄啶以不同电离状态存在时对细菌代谢的影响。采用UHPLC-MS检测细菌细胞内的甲氧苄啶分子，这表明与pH 5相比，在pH 7下回收了更多的药物;这与经典的生长曲线测量相关。使用FT-IR光谱法确定所有8种条件（3种药物水平和2种pH值水平的对照品）下可重现表型的回收率，并使用GC-MS生成总体代谢特征。除了发现在pH 7下核苷酸随着甲氧苄啶水平增加而减少的直接作用模式效应外，还观察到许多氨基酸的脱靶pH相关效应。此外，在pH 7时，抗生素水平增加时，可观察到抗微生物保护剂海藻糖更高的应激相关效应。这与葡萄糖和果糖的消耗以及乳酸盐相关产物以及乳酸盐和丙氨酸的增加相关。丙氨酸是已知的糖代谢调节剂，这种增加可能是为了提高糖的消耗，从而提高海藻糖的产量。这些结果为甲氧苄啶的作用提供了更广泛的视角。代谢组学指出了需要研究的替代代谢领域，以进一步了解甲氧苄啶的脱靶效应。
Metabolomics-based approaches were applied to understand interactions of trimethoprim with Escherichia coli K-12 at sub-minimum inhibitory concentrations (MIC≈0.2, 0.03 and 0.003 mg L-1). Trimethoprim inhibits dihydrofolate reductase and thereby is an indirect inhibitor of nucleic acid synthesis. Due to the basicity of trimethoprim, two pH levels (5 and 7) were selected which mimicked healthy urine pH. This also allowed investigation of the effect on bacterial metabolism when trimethoprim exists in different ionization states. UHPLC-MS was employed to detect trimethoprim molecules inside the bacterial cell and this showed that at pH 7 more of the drug was recovered compared to pH 5; this correlated with classical growth curve measurements. FT-IR spectroscopy was used to establish recovery of reproducible phenotypes under all 8 conditions (3 drug levels and control in 2 pH levels) and GC-MS was used to generate global metabolic profiles. In addition to finding direct mode-of-action effects where nucleotides were decreased at pH 7 with increasing trimethoprim levels, off-target pH-related effects were observed for many amino acids. Additionally, stress-related effects were observed where the osmoprotectant trehalose was higher at increased antibiotic levels at pH 7. This correlated with glucose and fructose consumption and increase in pyruvate-related products as well as lactate and alanine. Alanine is a known regulator of sugar metabolism and this increase may be to enhance sugar consumption and thus trehalose production. These results provide a wider view of the action of trimethoprim. Metabolomics indicated alternative metabolism areas to be investigated to further understand the off-target effects of trimethoprim.
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影响因子：
3.6
作者：
Goodacre, Royston;Broadhurst, David;Wulfert, Florian
通讯作者：
Wulfert, Florian
影响因子：
4.2
作者：
AlRabiah, Haitham;Correa, Elon;Goodacre, Royston
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Goodacre, Royston
影响因子：
3.2
作者：
Horlacher, R;Uhland, K;Boos, W
通讯作者：
Boos, W
影响因子：
158.5
作者：
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通讯作者：
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影响因子：
6.6
作者：
Griebling, TL
通讯作者：
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