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为进一步研究固氮植物酰脲代谢过程，系统研究了四季豆幼苗脲基乙醇酸酰胺水解酶的一些性质和底物类似物及其它化合物对该酶的影响。研究发现，四季豆干种子中有该酶，在种子萌发的第６ｄ酶活力迅速达到最大值（８．７２ｎｍｏｌ／ｍｉｎｍｇ）。幼苗根中酶的比活力最高，而茎和叶中的酶占总酶活力最多。该酶贮于－３０℃，至少稳定２８ｄ，而贮于４℃条件下，２１ｄ失活９．８％。经纯化的酶液在５５℃温度条件下处理５ｍｉｎ和１０ｍｉｎ，分别失活２５．０％和２８．３％，但１０％的甘油有部分保护作用。Ｃｏ２＋、Ｚｎ２＋、Ｆｅ２＋（全为２．０ｍｍｏｌ／Ｌ）几乎完全抑制酶反应。Ｌｉ２＋（２．０ｍｍｏｌ／Ｌ或０．２ｍｍｏｌ／Ｌ）没有影响，Ｃａ２＋、Ｂａ２＋、Ｍｏ＋７、Ａｇ＋（全为０．２ｍｍｏｌ／Ｌ）、Ａｇ＋（２ｍｍｏｌ／Ｌ）分别抑制２９．５％、２１．７％、２４．０％、３６．３％和５１．９％。测试其它３６种化合物（２．０ｍｍｏｌ／Ｌ）对酶反应的影响，结果：谷氨酰胺、谷氨酸、缬氨酸、天冬酰胺、脯氨酸和甘氨酸分别抑制酶活性的１８．６％、１９．８％、２８．６％、５．１％、１１．４％和９．０％；柠檬酸钠、硫代硫酸钠、草氨酸盐分别提高酶活力８７．４％、７４．７?
In order to further study the metabolic process of nitrogen-fixing plant ureides, some properties of urea glycolamide amidolytic enzyme and the effects of substrate analogs and other compounds on the enzyme were studied systematically. The study found that the seeds of dried bean curd with the enzyme, the germination of the first 6 days the enzyme activity reached its maximum (8.72nmol / minmg). The highest specific activity of enzyme in seedling root, and the enzyme in stem and leaf accounted for the highest total enzyme activity. The enzyme was stored at -30 ° C for at least 28 days, and was stored at 4 ° C for 21 days and was inactivated by 9.8%. The purified enzyme solution was treated at 55 ℃ for 5min and 10min, respectively, inactivation of 25.0% and 28.3%, respectively, but 10% glycerol partial protection. Co2 +, Zn2 +, Fe2 + (all 2.0 mmol / L) almost completely inhibited the enzyme reaction. Li2 + (2.0mmol / L or 0.2mmol / L) had no effect on Ca2 +, Ba2 +, Mo + 7, Ag + %, 24.0%, 36.3% and 51.9%. The effect of the other 36 compounds (2.0 mmol / L) on the enzyme reaction was tested. Results: Glutamine, glutamic acid, valine, asparagine, proline and glycine inhibited 18.6% , 19.8%, 28.6%, 5.1%, 11.4% and 9.0% respectively. Sodium citrate, sodium thiosulfate and oxalate increased the enzyme activity by 87.4% and 74%, respectively. 7?