Laber B, Amrhein N
Max-Planck-Institut für Biochemie, Abteilung Strukturforschung, Martinsried, Federal Republic of Germany.
Anal Biochem. 1989 Sep;181(2):297-301. doi: 10.1016/0003-2697(89)90246-7.
A spectrophotometric assay for the activities of mesodiaminopimelate decarboxylase and L-alpha-amino-epsilon-caprolactam hydrolase is described. With the commercially available enzyme saccharopine dehydrogenase lysine formed either by decarboxylation of meso-diaminopimelate or by hydrolysis of L-alpha-amino-epsilon-caprolactam is converted to saccharopine with the concomitant oxidation of NADH, which is monitored by the decrease in absorbance at 340 nm. For meso-diaminopimelate decarboxylase this assay can be performed either as an endpoint determination, when working with crude extracts, or as a continuous spectrophotometric assay of partially purified enzyme preparations. The activity of L-alpha-amino-epsilon-caprolactam hydrolase can only be assayed by the endpoint method because of the great differences in the pH optima of the hydrolase and the saccharopine dehydrogenase.
本文描述了一种用于测定中-二氨基庚二酸脱羧酶和L-α-氨基-ε-己内酰胺水解酶活性的分光光度法。利用市售的酶——酵母氨酸脱氢酶，由中-二氨基庚二酸脱羧或L-α-氨基-ε-己内酰胺水解形成的赖氨酸会转化为酵母氨酸，同时NADH被氧化，通过340nm处吸光度的降低来监测。对于中-二氨基庚二酸脱羧酶，该测定既可以在处理粗提取物时作为终点测定，也可以作为部分纯化酶制剂的连续分光光度测定。由于水解酶和酵母氨酸脱氢酶的最适pH差异很大，L-α-氨基-ε-己内酰胺水解酶的活性只能通过终点法测定。
