An enzymatic assay for metabolites of perfluoro-tagged 5-hydroxytryptophan.
An enzymatic assay for metabolites of perfluoro-tagged 5-hydroxytryptophan.
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全氟标记 5-羟基色氨酸代谢物的酶法测定。
DOI：
10.1007/s00253-003-1505-2
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
Guo,C
中科院分区：
文献类型：
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作者：
Snyder-Leiby,T;Dingman,S;Thomas,R;Guo,C
用芳香族氨基酸脱羧酶（AADC）处理5-羟色氨酸（5-HTP），并在吲哚环的不同位置（4、6、7位）上分别连接两种19 F原子标记。用HPLC分析所得样品。在第一项研究中，研究了直链七原子标签，检测到一个新的峰，puerophilofluoro-tagged 5-羟色胺。第二项研究表明，5-HTP在转化的大肠杆菌裂解物中转化为5-HT，但在未转化的裂解物中不转化。第三项研究调查了一种具有九个氟原子的标签，这些氟原子都在同一个核环境中，确定了作为AADC最佳底物的异构体。该新分子在吲哚环的6位上键合有标签。适合AADC活性位点的异构体可能遵循5-羟色胺在体内的生物合成路径，并且在19 F磁共振波谱研究中可能有用。本文所述的酶测定为筛选新化合物提供了一种有效且具有成本效益的工具。
l-5-hydroxytryptophan (5-HTP) with two types of multiple19F-atom tags bonded at various positions onto the indole ring (positions 4, 6, or 7) was exposed to aromaticl-amino acid decarboxylase (AADC) in lysates ofEscherichia coliJM109 which had been transformed with the plasmid pKKAADCII. Resulting samples were analyzed with HPLC. In the first study, which investigated a straight-chain seven-atom tag, a novel peak, putatively perfluoro-tagged serotonin, was detected. A second study demonstrated that 5-HTP was converted to 5-HT in transformedE.colilysate but not in untransformed lysate. A third study, investigating a tag with nine fluorine atoms all in the same nuclear environment, identified the isomer serving as the best substrate for AADC. This novel molecule had the tag bonded at the 6 position on the indole ring. Isomers that fit into the active site of AADC are likely to follow the biosynthetic path for serotonin in vivo and are potentially useful in19F magnetic resonance spectroscopy studies. The enzymatic assay described here provides an efficient and cost-effective tool for screening new compounds.