芜青中谷氨酸脱羧酶（Gad）酶性质的时空差异

The spatial and temporal variation of glutamate decarboxylase （Gad） property in Brassica rapa L. ssp rapa

摘要:

该文对芜青中谷氨酸脱羧酶（Gad）粗酶的提取和优化、酶活力最适反应条件、时空分布差异及光照影响等进行对比分析，同时利用超高效液相色谱法技术（UPLC）分析测定反应产物γ-氨基丁酸（Gaba）的含量。实验结果表明，提取Gad粗酶时加入纤维素酶能提高约70%酶活力。在最适条件对比实验中，对芜青芽苗、块根、茎生长点、茎及顶端分生组织分别进行测定，其中芽苗与顶端分生组织中的酶活力较高。光照对萌发中芽苗的Gad酶活力有较大影响，避光条件下酶活力下降约75%。结论，芜青芽苗Gad酶活力好且易于获取，转化谷氨酸反应生成γ-氨基丁酸的转化率高，有良好的工业应用前景。

Abstract:

In this study, crude enzyme extraction method, diversity property and light influence of glutamate decarboxylase(Gad) in Brassica rapa L. ssp rapa were analyzed. Ultra Performance Liquid Chromatography(UPLC) method was used to measure the production in Gad catalyzed progress-- Gamma - aminobutyric acid(Gaba). Adding 1% cellulase solution at homogenization step could improve the enzyme activity up to about 70% as much. Meanwhile, when pH were 4.5-6 with the temperature of 55℃，enzyme had reached its maximum activity ,on the other hand Ca2+ and coenzyme Plp didn't have any contribution. Among the different developing stages of Brassica rapa L. ssp rapa, extration of sucking seedling apical meristem could generate more Gaba. In general, with proper conditions, the sucking seedling could be the most efficient material and easily obtained, thus having considerable prospects of industrial use.