In vitro biotransformation of an arsenosugar by mouse anaerobic cecal microflora and cecal tissue as examined using IC-ICP-MS and LC-ESI-MS/MS
In vitro biotransformation of an arsenosugar by mouse anaerobic cecal microflora and cecal tissue as examined using IC-ICP-MS and LC-ESI-MS/MS
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DOI：
10.1039/b516275k
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发表时间：
2006-01-01
期刊：
影响因子：
4.2
通讯作者：
Thomas, DJ
中科院分区：
文献类型：
--
作者：
Conklin, SD;Ackerman, AH;Thomas, DJ
这项研究检查了小鼠盲肠对砷糖的化学和微生物转化。为了模拟哺乳动物胃肠道的低氧环境，反应混合物在厌氧条件下孵育。将从带状海带中提取的砷糖，3-[5'-脱氧-5-(二甲基胂酰基)-β-呋喃核糖基氧基]-2-羟基丙烷磺酸，As(392)，添加到含有盲肠微生物区系或盲肠组织匀浆的反应混合物中。这些反应混合物在 0 或 37 摄氏度下孵育长达 48 小时，以监测砷糖的生物转化。通过 IC-ICP-MS 和 LC-ESI-MS/MS 对反应混合物进行的分析表明，砷糖在 37 摄氏度下不到 1 小时内主要转化为硫类似物 (95%)。在 0 摄氏度下，As(392) 转化为硫类似物的速度要慢得多（48 小时后转化率为 21%）。在含有盲肠组织匀浆的反应混合物中，As(392) 转化为其硫类似物的速度较慢（37 摄氏度下 48 小时后转化率为 77%）。在所有反应混合物中，添加的砷糖的量与所有检测到的含砷产物的总和之间发现良好的质量平衡。在所有含有盲肠微生物区系的反应混合物中形成的含硫砷糖的 LC-ESI-MS/MS 谱图与合成标准品的谱图相比较。这些结果表明胃肠道的厌氧微生物群可以迅速将摄入的砷糖转化为硫类似物。这种生物转化可能会影响砷糖中砷的后续吸收、代谢和处置。
This investigation examined chemical and microbiological transformations of an arsenosugar by mouse cecum. To mimic the low oxygen environment in the mammalian gastrointestinal tract, reaction mixtures were incubated under anaerobic conditions. An arsenosugar extracted from ribbon kelp, 3-[5'-deoxy-5-( dimethylarsinoyl)-beta-ribofuranosyloxy]-2-hydroxypropanesulfonic acid, As( 392), was added to reaction mixtures that contained either cecal microflora or cecal tissue homogenate. These reaction mixtures were incubated at 0 or 37 degrees C for up to 48 hours to monitor biotransformation of the arsenosugar. Analysis of the reaction mixtures by IC-ICP-MS and LC-ESI-MS/MS indicated that the arsenosugar was converted primarily ( 95%) to its sulfur analog in less than 1 h at 37 degrees C. Conversion of As( 392) to its sulfur analog was much slower at 0 degrees C ( 21% conversion after 48 h). In reaction mixtures with cecal tissue homogenate, conversion of As( 392) to its sulfur analog was slower ( 77% conversion after 48 h at 37 degrees C). A good mass balance was found in all reaction mixtures between the amount of arsenosugar added and the sum of all detected arsenic-containing products. LC-ESI-MS/MS spectra of the sulfur-containing arsenosugar formed in all reaction mixtures containing cecal microflora compared well with those of a synthetic standard. These results suggest that the anaerobic microflora of the gastrointestinal tract can rapidly convert ingested arsenosugars to sulfur analogs. This biotransformation may affect the subsequent absorption, metabolism, and disposition of arsenic present in arsenosugars.