Determination of the Activity of 1-Deoxy-d-Xylulose 5-Phosphate Synthase by Pre-column Derivatization-HPLC Using 1,2-Diamino-4,5-Methylenedioxybenzene as a Derivatizing Reagent
作者:Yan-Fei Liang、Hui Liu、Heng Li、Wen-Yun Gao
DOI:10.1007/s10930-019-09816-9
日期:2019.4.15
α-Ketoacids can be determined by HPLC through pre-column derivatization with 1,2-diamino-4,5-methylenedioxybenzene (DMB) as a derivatizing reagent. Using this method, the specific activity and the steady-state kinetic of 1-deoxy-d-xylulose-5-phosphate synthase (DXS) were measured. Firstly, DXS substrate pyruvate was derivatized with DMB in acidic solution; then the corresponding quinoxalinone was elucidated
α-酮酸可通过HPLC通过以1,2-二氨基-4,5-亚甲基二氧基苯(DMB)作为衍生试剂的柱前衍生来确定。使用这种方法,1-脱氧-d的比活和稳态动力学测定了-木酮糖-5-磷酸合酶(DXS)。首先,在酸性溶液中用DMB衍生化DXS底物丙酮酸;然后通过LC–ESI–MS阐明相应的喹喔啉酮,并通过HPLC-UV进行定量。最佳衍生化条件如下:pH值为1.0的水性介质,反应温度为80°C,反应时间为60分钟,DMB与丙酮酸的摩尔比为10:1。用甲醇和水的混合物(60:40,v / v)作为流动相,通过等度洗脱进行HPLC。该方法的检出限和线性相关范围分别为0.05 µM和0.002-1.0 mM(R = 0.994)。六次测定的相对标准偏差(RSD)为2.48%。用该方法测定的丙酮酸DXS的稳态动力学参数与报道的数据相同。