A liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) method for the separation and quantification of the enantiomers of N-methylaspartate and N-methylglutamate, after derivatization with Nα-(5-fluoro-2,4-dinitrophenyl)-L-leucinamide was established. The time required for the LC-ESI-MS/MS analysis was within 20 min and the detection limit was approximately 10 fmol per injection, demonstrating that this method can be used for the rapid determination of D-aspartate N-methyltransferase activity in the ark shell clam Scapharca broughtonii.Abbreviations: NMDA: N-methyl-D-aspartate; NMLA: N-methyl-L-aspartate; NMDG: N-methyl-D-glutamate; NMLG: N-methyl-L-glutamate; NMA: N-methylaspartate; NMG: N-methylglutamate; HPLC: high-performance liquid chromatography; SAM: S-adenosyl-L-methionine; OPA: o-phthalaldehyde; LC-ESI-MS/MS: liquid chromatography-electrospray ionization-tandem mass spectrometry; FDLA: Nα-(5-fluoro-2,4-dinitrophenyl)-L-leucinamide; FDAA: Nα-(5-fluoro-2,4-dinitrophenyl)-L-alaninamide; ESI: electrospray ionization; LC-ESI-MS: liquid chromatography-electrospray ionization-mass spectrometry; MS/MS: tandem mass spectrometry.

中文翻译：

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液相色谱-电喷雾串联质谱法测定方舟壳中的d-天冬氨酸N-甲基转移酶活性。

Nα-（5-氟-2,4）衍生化后的液相色谱-电喷雾串联质谱（LC-ESI-MS / MS）方法用于分离和定量N-天门冬氨酸和N-谷氨酸的对映体-二硝基苯基）-L-亮氨酸酰胺被建立。LC-ESI-MS / MS分析所需的时间在20分钟以内，每次进样的检出限约为10 fmol，表明该方法可用于快速测定方舟中D-天冬氨酸N-甲基转移酶的活性壳蛤Scapharca Brownii。缩写：NMDA：N-甲基-D-天门冬氨酸；NMLA：N-甲基-L-天门冬氨酸；NMDG：N-甲基-D-谷氨酸；NMLG：N-甲基-L-谷氨酸；NMA：N-甲基天冬氨酸；NMG：N-甲基谷氨酸；HPLC：高效液相色谱法；SAM：S-腺苷-L-蛋氨酸；OPA：邻苯二甲醛；LC-ESI-MS / MS：液相色谱-电喷雾电离串联质谱法；FDLA：Nα-（5-氟-2,4-二硝基苯基）-L-亮氨酰胺；FDAA：Nα-（5-氟-2,4-二硝基苯基）-L-丙氨酰胺；ESI：电喷雾电离；LC-ESI-MS：液相色谱-电喷雾电离质谱。MS / MS：串联质谱。