A coupled system using extremely different enzymes with incompatible cofactors and reaction conditions has been constructed using standard liquid chromatographic formats and open tubular formats. One of the significant aspects of the present invention lies in the development of the liquid chromatographic on-line enzyme cascade. This has been illustrated by the biosynthetic pathway involving dopamine beta-hydroxylase and phenylethanolamine N-methyltransferase which encompass the synthesis of the key neurotransmitters, norepinephrine and epinephrine. The results demonstrate for the first time the immobilization of dopamine beta-hydroxylase and phenylethanolamine N-methyltransferase. The IMERs are active and can be used in a liquid chromatographic format for qualitative and quantitative determinations. The IMER-HPLC system can be used to carry out standard Michaelis-Menten enzyme kinetic studies and to quantitatively determine enzyme kinetic constants, identify specific enzyme inhibitors, provide information regarding the mode of inhibition and the inhibitor constants (K
i
). A second significant aspect of the present invention lies in the ability of the immobilized enzyme reactors to be used independently or as a combination, thus providing a unique opportunity to explore the interrelationships between these enzymes, to investigate the source of diseases and to design new drug entities for identified clinical syndromes.
利用标准
液相色谱格式和开放式管式格式,构建了一个使用极其不同的酶与不相容的辅助因子和反应条件的耦合系统。本发明的一个重要方面在于开发了
液相色谱在线酶级联。
多巴胺 beta-羟化酶和
苯乙醇胺 N-甲基转移酶参与的
生物合成途径说明了这一点,这两种酶包括合成关键的神经递质--
去甲肾上腺素和
肾上腺素。研究结果首次证明了
多巴胺 beta-羟化酶和
苯乙醇胺 N-甲基转移酶的固定化。IMER 具有活性,可用于
液相色谱法进行定性和定量测定。IMER-HPLC 系统可用于开展标准的 Michaelis-Menten 酶动力学研究,定量测定酶动力学常数,确定特定的酶
抑制剂,提供有关抑制模式和
抑制剂常数(K
i
).本发明的第二个重要方面在于固定化酶反应器能够独立使用或组合使用,从而为探索这些酶之间的相互关系、研究疾病的来源以及为已确定的临床综合症设计新的药物实体提供了独特的机会。